This resource was updated as part of the veterinary review process. It was originally published on April 20, 2018.
Unfortunately for the humans looking out for them, sheep tend to hide signs of illness and injury until they are no longer able to do so. Therefore, in order to catch and respond to health issues as quickly as possible, you’ll need to spend a lot of time observing and getting to know your residents so you are better able to catch less obvious signs of concern. Additionally, by conducting regular full-body health checks, you’ll be able to learn what healthy looks and feels (and smells!) like and will be more likely to catch issues early on. Be sure to read our guide to sheep health checks to familiarize yourself with the signs that something may be amiss with a sheep resident. For more information on health challenges that commonly affect lambs, check out our resource here. For information about health challenges that commonly affect pregnant and lactating sheep, check out our series here.
Issues By Body System Affected
Circulatory System: Anaplasmosis, Anemia, Anthrax, Bluetongue, Copper Toxicity, White Muscle Disease
Gastrointestinal System: Barber Pole, Bloat, Clostridial Disease (Enterotoxemia, Struck, Necrotic Enteritis, Overeating Disease, Pulpy Kidney, Tetanus), Coccidiosis, Grain Overload (Rumen Acidosis, Lactic Acidosis), Johne’s Disease, Liver Flukes, Tapeworms
Lymphatic System: Caseous Lymphadenitis (CL)
Musculoskeletal System: Arthritis, Bluetongue, Infectious Foot Rot (Contagious Hoof Rot), Interdigital Dermatitis (Foot Scald), Laminitis, Overgrown Hooves, Ovine Progressive Pneumonia (OPP), White Muscle Disease
Nervous System: Anthrax, Parelaphostrongylus Tenuis (Meningeal Worm, Deer Worm, Brain Worm), Listeriosis, Ovine Progressive Pneumonia (OPP), Tetanus, Thiamine Deficiency
Reproductive System: Bluetongue, Listeriosis, Ovine Progressive Pneumonia (OPP)
Respiratory System: Bluetongue, Sheep Nasal Bot Fly (Oestrus ovis), Bottle Jaw, Caseous Lymphadenitis (CL), Lungworms, Mastitis, Ovine Progressive Pneumonia (OPP), Pneumonia
Urinary System: Pizzle End Rot, Urinary Calculi
Integumentary System: Abscesses, Caseous Lymphadenitis (CL), Fly Strike, Keds, Lice, Mange, Sore Mouth (Orf)
Sensory System: Entropion, Pink Eye (Infectious Keratoconjunctivitis)
Abscesses
Abscesses are pockets of pus that can develop internally or externally. They can develop in any area of the body, but some common sites for sheep include their feet, face, and neck. Abscesses can form for a variety of reasons, including infections, poor wound management, and benign reactions to vaccinations or injectable medications. Abscesses can also form as a result of Caseous Lymphadenitis (CL), a highly contagious condition that can cause internal and external abscesses. This disease is spread through contact with the pus, so separating individuals with external abscesses until/unless it is confirmed not to be CL is typically recommended.
In the event of a suspected external abscess, it should be first evaluated by a veterinarian or experienced caregiverSomeone who provides daily care, specifically for animal residents at an animal sanctuary, shelter, or rescue. – if appropriate, they can aspirate the lump to determine if it is an abscess or not. Depending on the location, size, and whether or not the sheep is displaying other signs of concern, your veterinarian may decide to lance the abscess. In most cases, a culture will be recommended to determine the best course of action (performing a culture will also reveal if the cause is CL or not). Your veterinarian will be able to advise you about any necessary treatments based on the cause of the abscess. If you have not been trained to identify and lance an abscess, you must work closely with your veterinarian. Not all external lumps are abscesses, and cutting into tumors or other masses or structures could result in serious issues. Also, be aware that any abscess on the neck or near major blood vessels should always be evaluated by a veterinarian. In these instances, it may be too dangerous to lance the abscess due to the risk of major bleeding.
Sheep can also develop abscesses in their feet, affecting either the heel or the toe. Whereas some other foot issues tend to affect more than one foot, foot abscesses may only affect one claw. While not the only possible cause, individuals may develop a foot abscess following trauma to the foot, such as from stepping on something sharp or from improper hoof trimming. Signs of a foot abscess include swelling of the affected claw and swelling at the coronary band, heat, and acute lameness, with the individual often reluctant to bear weight on the affected claw. If the abscess has ruptured, you may note discharge coming from a draining tract. In cases where the abscess has not yet ruptured, your veterinarian may open it up while trimming the hoof, or they may lance the swollen area. Be sure to consult with your veterinarian regarding treatment, which may include analgesics, antibiotics (systemically or flushed into an open abscess), and bandages or blocks to protect the affected claw. If foot abscesses are a common occurrence, work with your veterinarian to identify possible causes so you can work to address them.†
Source:
Foot Abscesses In Sheep | Merck Veterinary Manual
Abscess | Veterinary Handbook For Sheep, Goats, And Cattle (Non-Compassionate Source)
Anaplasmosis
Anaplasmosis in sheep is caused by the bacterium Anaplasma ovis, which parasitizes red blood cells. While many infected sheep will remain asymptomatic, it can cause severe disease, especially in older sheep. Anaplasmosis is an infectious disease that is typically transmitted by insects such as ticks and biting flies, but can also be spread through any practices that may expose sheep to infected red blood cells (such as by reusing needles or not sterilizing surgical equipment). A. ovis can also be transmitted in utero. Signs of anaplasmosis include fever, pale mucous membranes, weakness, and dark urine. Infected individuals may exhibit additional signs such as depression, constipation, an elevated respiratory rate, and inappetence. Be sure to contact your veterinarian immediately if one of your residents is showing signs of anaplasmosis. They can diagnose the issue and recommend treatment, which may include intravenous antibiotics (typically a tetracycline drug) and possibly a blood transfusion.†
Sources:
Anaplasmosis | Purdue University College Of Veterinary Medicine
Anaplasmosis | Merck Veterinary Manual
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Anemia
AnemiaAnemia is a condition in which you don't have enough healthy red blood cells to carry adequate oxygen to the body's tissues. is defined as a lower than normal number of healthy red blood cells in circulation. This may be due to a loss of red blood cells (such as from trauma, hemorrhage, or blood-sucking parasites), damage/destruction of red blood cells, or failure to produce normal amounts of red blood cells. Red blood cells carry oxygen and nutrients throughout the body, and without enough healthy red blood cells in circulation, the body can become depleted of oxygen. Severe anemia can be life-threatening.
In sheep, anemia is characterized by pale mucous membranes, especially the mucous membranes of the lower eyelid. An anemic sheep might be more lethargic, have a dull or shabby coat, have an increased heart rate, and lose weight. Anemic individuals may also develop Bottle jaw (intermandibular edemaEdema is the abnormal accumulation of fluid in tissues of the body.). Anemia can be diagnosed via blood testing, namely a complete blood count (CBC) or packed cell volume (PCV) test. Your veterinarian may recommend additional diagnostics to help determine the underlying cause.
If a resident is anemic, it is imperative to identify the cause, which could be due to parasitic disease (especially Barber Pole worm), a non-parasitic disease, ingestion of a toxin, or trauma. In areas where Barber Pole worms are common, this is typically the most common cause of anemia in sheep and goats. Depending on the underlying cause and severity of the anemia, addressing the underlying cause may be all that is needed. If an individual has severe anemia, they may also recommend a blood transfusion. Be sure to work closely with your veterinarian if one of your residents appears to be anemic. They can help determine the cause of the anemia and offer treatment recommendations. If you have not already done so, talk to your veterinarian about using the FAMACHA system to regularly evaluate residents for signs of anemia.†
Sources:
Anemia In Animals | Merck Veterinary Manual
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Anthrax
Anthrax is caused by Bacillus anthracis spores, which can lie dormant in soil for many years. The bacteria is more common in temperate climates and can come to the surface after heavy rains, especially after periods of drought. Animals who graze are susceptible to the disease after eating contaminated grass. Signs of anthrax include depression, incoordination, staggering, trembling, convulsions, excitement, high fever, bleeding, and, unfortunately, typically death. If you suspect a sheep has anthrax, you must contact your veterinarian immediately. Because of how rapidly the condition progresses, immediate antibiotic treatment is key. Additionally, your veterinarian can make recommendations to help protect other residents and the humans who care for them. This may include the use of vaccines. Please note that anthrax is zoonotic, and confirmations of anthrax must be reported. If your veterinarian has diagnosed anthrax, consult with your human physician regarding the risk of transmission to yourself and the symptoms you should watch for (and encourage others who have had contact with the individual to do the same).†
Source:
Anthrax | World Organisation For Animal Health
Arthritis
There are many types of arthritis with different causes (including septic arthritis, which can be quite common in lambs who did not receive colostrum), but like most animals, degenerative arthritis (osteoarthritis) tends to be quite common in sheep as they age. Sheep may also develop arthritis due to Ovine Progressive Pneumonia (OPP). Symptoms of arthritis will vary depending on the affected area and cause, but typically include abnormal gait, shifting of weight, lameness, and reduced activity. Sheep with arthritis may spend more time lying down, putting them at risk of developing pressure sores, and they may have difficulty getting up.
Individuals showing signs of mobility issues should be evaluated by a veterinarian to determine the underlying cause and best course of action. Without pain management, arthritis can cause chronic pain (ranging in severity from mild to debilitating) and can affect an individual’s activity level and quality of life. While there is no cure for osteoarthritis, your vet will be able to recommend a treatment plan based on the specific cause, while taking into account their overall health. They may recommend a non-steroidal anti-inflammatory drug (NSAID), such as meloxicam or banamine, or other analgesics, such as tramadol or gabapentin.
Another treatment option to consider, and one that can be used in conjunction with the analgesics listed above, is a chondroprotective agent such as glucosamine to help repair joint cartilage and soothe inflammation. Some sanctuaries have also seen some success treating arthritis pain with alternative therapies such as acupuncture and veterinary laser therapy as well as more natural remedies (in conjunction with conventional medication) such as Boswellia (also known as Indian frankincense), turmeric, and small ruminant-safe herbal formulas designed for joint health. Your veterinarian may also recommend a topical treatment such as diclofenac sodium ointment (ex. Surpass) or a formula designed for human use such as Aspercreme. Be sure to talk to your veterinarian about the most appropriate pain management plan for each of your residents and talk to them about conducting blood work before certain treatments (such as NSAID treatment) to ensure the treatment is not contraindicated and to establish a baseline against which to compare future blood work results. We also recommend talking to them about conducting regular blood work for individuals on certain long-term treatments to monitor organ function and watch for adverse effects.
In addition to offering treatments to reduce inflammation and pain, make sure that their environment is as arthritis-friendly as can be, minimizing steep grades or long walks to food or water, and be sure to provide ample bedding to reduce their risk of developing pressure sores if they are spending more time lying down than usual. While osteoarthritis does not only affect elderly individuals, it certainly is a common health condition in elderly residents. You can read more about caring for elderly sheep here.*
Sources:
Additional Care Recommendations For Older Sheep | The Open Sanctuary Project
Indian Frankincense | Arthritis Foundation
Barber Pole
Barber pole worm (Haemonchus contortus, sometimes called wireworm) is a gastrointestinal roundworm that can cause serious disease in sheep, goats, llamas, and alpacas. While other gastrointestinal parasites can cause illness in small ruminants and camelids, barber pole worm is especially dangerous because it is a blood-sucking parasite that has the potential to cause life-threatening anemia. To further complicate things, anthelmintic resistance (resistance to dewormers) is a serious and growing issue, though the degree of resistance and to which drugs worms are resistant will vary region by region and also property to property. For more information on barber pole worm, including ways to slow the development of anthelmintic resistance, check out our in-depth resource here.
Source:
Advanced Topics In Resident Health: Barber Pole Worm | The Open Sanctuary Project
Bloat
In ruminants, a significant amount of gas is produced during the digestive process and is naturally released through eructation (belching). Bloat occurs if this gas is not able to be released for some reason. The build-up of gas causes the rumen to expand, which will displace and put pressure on internal organs and can make it difficult for the individual to breathe. Bloat should be considered a health emergency and must be addressed immediately. You can read more about this condition here.
Source:
Bloat In Ruminants | The Open Sanctuary Project
Bluetongue
Bluetongue is a viral infection that can affect both domesticatedAdapted over time (as by selective breeding) from a wild or natural state to life in close association with and to the benefit of humans and wild ruminant species. Of the domesticated species, sheep are the most severely affected. Transmission of bluetongue virus (BTV) occurs primarily via biting midges (Culicoides spp.), though not all species of Culicoides act as vectors of BTV. While some other bloodsucking insects may be able to act as mechanical vectors, according to the Merck Veterinary Manual, they are of minor significance.
In many parts of the world, BTV infections are often subclinical. However, BTV infection can cause serious and potentially fatal illness. Initial signs of BTV infection include fever and lethargy, which may be followed in a few days by edema (fluid build-up) of the mouth, lower jaw (bottle jaw), eyelids, or ears. Other signs include lameness, depression, excessive salivation, and congestion of the nose, mouth, conjunctiva, or coronary band. Individuals often have profuse nasal discharge, which is initially thin and clear and then becomes mucopurulent. BTV can cause small hemorrhages of the nasal and oral mucous membranes as well as ulceration of the mouth. In some cases, the individual’s tongue will swell and become a blueish color (hence the name ‘bluetongue’). BTV can also cause reproductive issues. Secondary bacterial infections are possible, and in severe cases, pulmonary edema may result in difficulty breathing or even asphyxiationAsphyxiation is the state or process of being deprived of oxygen, which can result in unconsciousness or death; suffocation..
Be sure to contact your veterinarian immediately if one of your residents is showing signs of bluetongue. In areas where the disease is endemic, your veterinarian may be able to make a diagnosis based on clinical signs alone. However, there are diagnostic tests they may recommend to confirm. Treatment typically includes supportive care and possibly antibiotics to address secondary infections. Because oral lesions often make eating painful, individuals may need encouragement to eat and may benefit from soft food such as soaked timothy pellets. Your veterinarian can recommend specific interventions based on the needs of the individual. Vaccination may be advisable if you are in an area where this disease is endemic, but you should consult with an experienced veterinarian to establish an appropriate protocol for your sanctuary and to determine which of the available vaccines will offer the best protection based on the virus strains in your area.†
Sources:
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Overview of Bluetongue | Merck Veterinary Manual (Non-Compassionate Source)
Bottle Jaw
Bottle jaw is the term commonly used to describe edema in the lower mandible, which manifests as a visibly swollen area under the jaw. While it can have other causes, most often bottle jaw develops because of reduced oncotic pressure resulting from anemia or hypoproteinemia (low protein levels in the blood). Bottle jaw is not a disease unto itself, but rather is a sign of disease. In sheep and goats, bottle jaw is most often associated with barber pole worm infections, though it can be caused by other internal parasites or other health challenges, such as Johne’s disease. Be sure to work with your veterinarian if one of your residents is showing signs of bottle jaw – it is important to diagnose the underlying cause in order to make treatment decisions.†
Sources:
Bottle Jaw | Veterinary Handbook For Cattle, Sheep & Goats
Caseous Lymphadenitis (CL)
Caseous lymphadenitis is a contagious and chronic disease that causes abscesses in sheep and goats and is caused by the bacterium Corynebacterium pseudotuberculosis. For more information on this disease, check out our resource Caseous Lymphadenitis In Small Ruminants.
Clostridial Disease
There are many clostridial organisms that can live in the soil and even in the gastrointestinal tract of healthy animals. While there are a host of clostridial organisms that can cause disease in sheep, the most common are Clostridium perfringens types C and D and Clostridium tetani. Because of the prevalence of these pathogens and the fact that they produce toxins that often cause fatal disease, vaccination is universally recommended in North America. There is a three-way vaccine, referred to as CDT, that protects against all three of these pathogens and the diseases they cause, as well as an eight-way vaccine that protects against additional clostridial diseases as well. Talk to your veterinarian about which vaccine makes the most sense for your residents, as additional clostridial diseases may be a concern in certain regions.
C. perfringens type C most often affects young lambs, causing hemorrhagic enterotoxemia or necrotic enteritis, but can also affect adults, causing a disease called “struck”. Lambs may die without showing signs of illness, but more often they will develop diarrhea that is yellow, and they may have streaks of blood in their feces. Affected lambs will not want to eat, will show signs of colic, and will tense their abdominal muscles, especially when being handled. Unfortunately, this disease is often fatal, ending in convulsions and coma. Adult sheep with “struck” may die suddenly or may show signs of toxemia. If C. perfringens type C infection is recognized early, treatment with antibiotics, Clostridium antitoxin, and supportive care may help, but often once there are clinical signs of disease, treatment is not successful.
C. perfringens type D causes classic enterotoxemia in sheep and is also referred to as “overeating disease” and “pulpy kidney disease”. This disease is often associated with over-ingestion of grain but can also result from over-ingestion of milk or lush pasture and can also be caused by an abrupt change in diet (such as sudden introduction of lush pasture or increase in grain). As a result of over-ingestion or sudden diet changes, C. perfringens type D proliferates and produces toxins. While it occurs most often in lambs, unvaccinated adults can also be affected. Some sheep may die before or soon after showing signs of illness. Signs of enterotoxemia caused by C. perfringens type D include an elevated respiratory rate, elevated heart rate, fever, and inappetence. Individuals will show signs of colic, such as laying flat on their side and tensing their abdominal muscles, and develop neurologic signs that progress to seizures or coma. In the final stages of disease, lambs may develop watery, yellow diarrhea. If caught early, treatment with antibiotics, Clostridium antitoxin, and supportive care, as well as adjustments to their diet may help.
C. tetani is found in the soil and causes tetanus when introduced to the tissue via a wound, surgical procedure, or even intramuscular injection. The incubation period varies, with signs of tetanus developing anywhere between 1 and 60 days after introduction of C. tetani. Tetanus is a progressive disease. Though often missed, the first sign of tetanus is often a tensing of the muscles in the head and neck. Within the first 24 hours, individuals often develop bloat. As the condition progresses, the individual will develop more generalized stiffness that involves their head, neck, limbs, and tail. Affected sheep may lay on their side and be unable to rise or stand in a “sawhorse” stance. Treatment involves high doses of antibiotics, administration of tetanus antitoxin, medications to relieve muscle spasms, supportive care, and if there is a necrotic wound present, debridement of the wound. The individual should be kept in a quiet, dark space with ample bedding and minimal stimulation while they recover. Unfortunately, death due to respiratory paralysis is common. If a young or new resident has not yet been vaccinated and requires surgery (such as neutering) or becomes wounded, your veterinarian can administer tetanus antitoxin to provide temporary protection.
Your best course of action is to prevent the above diseases by establishing an appropriate vaccination program with your veterinarian, such as administration of the three-way CDT vaccine. Generally, newly rescued adult sheep with unknown vaccination status should be vaccinated soon after arrival so long as they are healthy enough. Lambs fed an appropriate amount of colostrum from a vaccinated individual receive passive immunity to these clostridial diseases. This immunity is temporary and will begin to fade when lambs are about six weeks old. Vaccinating these lambs when they are about 6-8 weeks old will ensure continued protection against these dangerous diseases. Lambs who did not receive colostrum from a vaccinated individual (and therefore did not receive passive immunity) should be vaccinated for clostridial diseases at an earlier age, typically when they are between 3-4 weeks old. Lambs with unknown immunity or vaccination status should also be vaccinated between 3-4 weeks of age. Please consult with your veterinarian for specific guidance. Be sure to administer subsequent boosters following the manufacturer’s instructions or your veterinarian’s recommendations.†
Sources:
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Large Animal Internal Medicine 5th Edition | Bradford P. Smith (Non-Compassionate Source)
CDT Vaccinations | Maryland Small Ruminant Page (Non-Compassionate Source)
Enterotoxemias | Merck Veterinary Manual (Non-Compassionate Source)
Clostridial Diseases | Cornell University College Of Veterinary Medicine (Non-Compassionate Source)
Coccidiosis
While it is common for mature sheep to shed the parasitic protozoa coccidia in their feces, coccidiosis is primarily a concern in lambs under six months of age and is most likely to occur in agricultural settings where sheep are confined, overcrowded, or kept in unsanitary conditions. Clinical disease can be precipitated by stress, and the disease is often associated with the stress of weaning. While healthy, mature individuals are mostly resistant to clinical disease, individuals with an impaired immune system or who are under extreme stress could develop coccidiosis.
There are numerous species of coccidia found in the environment, but not all are pathogenic (disease-causing). Additionally, while it used to be thought that sheep and goats were affected by the same species of coccidia, it is now understood that coccidia is host-specific. Pathogenic species that affect sheep include Eimeria crandallis and E. ovinoidalis. High numbers of pathogenic coccidia cause damage to the lining of the intestine, affecting nutrient absorption. Diarrhea is a common sign of coccidiosis.
Eimeria oocysts (egg-like structures) are passed in feces of infected individuals and become infective a few days later (timing depends on environmental conditions). Once infective, oocysts are difficult to kill in the environment – disinfectants are not effective, but direct sunlight, steam cleaning, and extreme desiccation can reduce environmental contamination. Other individuals become infected by ingesting infective oocysts in contaminated food or water or when grooming themselves or their companions. Though healthy, mature individuals are not at risk of developing clinical disease, they can act as reservoirs for the parasite, resulting in contamination of the environment.
While fecal testing can be used to detect oocysts, diagnosis is not straightforward. Remember, not all strains of coccidia are pathogenic, and healthy individuals can pass coccidia in their feces, so the presence of coccidia in a fecal sample does not necessarily mean that treatment is necessary. Additionally, early in the disease, an individual may have a negative fecal test despite being infected. It’s important to work closely with your veterinarian to interpret fecal test results and to evaluate residents showing signs of concern. They can help you determine if and when treatment is necessary.*
Sources:
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Coccidiosis: Diagnosis, Treatment, and Control | OSU Sheep Team (Non-Compassionate Source)
Coccidiosis Of Sheep | Merck Veterinary Manual (Non-Compassionate Source)
Diagnosis, Treatment, And Prevention Of Common Small Ruminant Parasites | Dr. Mary Smith, DVMDoctor of Veterinary Medicine, an academic degree awarded to veterinarians in many countries. (Non-Compassionate Source)
Copper Toxicity
Copper toxicity is especially dangerous in sheep because their liver accumulates copper much more readily than in other animals. Although copper is essential for sheep, too much copper can cause anemia, lack of appetite, lethargy, teeth grinding, increased thirst, jaundice, dark red-colored urine, and diarrhea. Copper can accumulate in a sheep’s liver for up to a year without any symptoms until the liver releases a large amount at once, causing damage to their red blood cells. In addition to copper intake levels that are too high, copper toxicity can also be caused by liver damage or a lack of dietary molybdenum, sulfur, zinc, or calcium. Left untreated, copper toxicity can be fatal in only a few days after presenting symptoms. Unfortunately, the prognosis is poor in severely affected individuals.
If you suspect copper toxicity in one of your sheep residents, contact a veterinarian immediately. They can recommend appropriate treatments based on the situation, such as those that reduce copper absorption, enhance copper elimination, and reduce damage to red blood cells, and they can also provide supportive care as needed. It’s also imperative you determine the cause of the copper toxicity to avoid toxicity in other residents. Your veterinarian may recommend treatment for flockmates even if they are not showing clinical signs of toxicity.
The best prevention includes ensuring that the sheep are not getting too much copper in their diet and that their diet is properly balanced. Make sure that sheep are not given access to minerals or food formulas not explicitly approved for sheep, as even goat minerals have too much copper for a sheep’s body. Also, consider other potential sources of copper, such as foot baths containing copper or even water sources.†
Sources:
Overview Of Copper Poisoning | Merck Manual Veterinary Manual
Copper Toxicity In Sheep | Maryland Small Ruminant Page (Non-Compassionate Source)
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Entropion (Or, Inverted Eyelid)
Entropion is a condition in which the eyelid rolls inward causing eyelashes and the hair around the eye to come into contact with the eye, resulting in irritation. This condition can be congenital and is one of the most common eye issues in neonatal lambs. Congenital entropion usually affects the lower eyelids of both eyes. Non-congenital entropion can affect individuals of any age and typically affects only one eye but may affect either the top or bottom eyelid. This type of entropion can develop as a result of trauma or secondary to certain eye conditions. It can also develop in individuals who are emaciated or severely dehydrated and can also affect elderly individuals due to a loss of retrobulbar fat.
Individuals with entropion will show signs of eye irritation, such as squinting or rubbing of the eye, as well as tearing and eye discharge. Upon closer inspection, you will be able to see that the eyelid is inverted. Your veterinarian can recommend treatment based on the severity of the case and the cause. Treatment may include eye ointments, skin sutures to evert the eyelid, or surgical correction. Congenital entropion tends to improve over time, so it’s often recommended to hold off on surgical correction to see if the condition resolves, in the meantime using non-surgical interventions to evert the eyelid and treat the eye. Left untreated, entropion can cause corneal scarring and ulceration.†
Sources:
Eyelids | Merck Veterinary Manual
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Fly Strike
Fly strike refers to a maggot infestation. While any farmed animal sanctuaryAn animal sanctuary that primarily cares for rescued animals that were farmed by humans. resident can suffer from fly strike, sheep are especially vulnerable because flies are attracted to soiled wool. There are numerous species of blowfly that commonly cause fly strike in sheep, and species of concern vary by region. Some fly species will attack living tissue, while others only infest wounds with necrotic tissue. Wounds in woolen sheep may be more likely to go unnoticed, allowing them to fester and making them more likely to attract flies. In addition to soiled wool and wounds, foot rot can attract flies and result in fly strike.
In a sanctuary setting where individuals are regularly observed and evaluated, fly strike is far less common than on a commercial farm. However, you should be sure to clean up individuals with soiled wool (particularly urine-soaked wool in females or the soiled bum of anyone with diarrhea). Keep a close eye out for wounds or other conditions that could lead to fly strike (such as foot rot), and be sure to protect these areas from flies and monitor them regularly. Daily observation, cleaning or partially shearing wool that is soaked with urine or matted with feces, implementing fly mitigation strategies, and close monitoring of anyone who has a condition that makes them more vulnerable to fly strike will help prevent this issue and ensure that if someone does develop fly strike, you will be more likely to catch it early. If you note flies congregating on a specific area of a resident’s body, be sure to investigate to see if there is a wound that you did not know about.
If you find that one of your residents has fly strike, consult with your veterinarian for guidance. For minor infestations, your veterinarian may recommend applying hydrogen peroxide or another treatment to kill maggots, but for more severe infestations, manual removal of maggots may be necessary. In addition to eradicating the maggots, your veterinarian may recommend other treatments depending on the severity.*
Sources:
Blowfly Strike (Cutaneous Myiasis, Maggots) | NADIS Animal Health (Non-Compassionate Source)
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Grain Overload (Rumen Acidosis, Lactic Acidosis)
Grain overload occurs when a ruminant eats highly digestible carbohydrates in large quantities or when they are not used to eating such foods. In a sanctuary setting, grain overload is most often caused by residents accidentally gaining access to grain storage areas but could also occur if a resident who requires grain supplementation is fed too much or is not slowly transitioned onto this diet. Depending on the circumstances, it’s not uncommon to find that the dominant member of the group is most affected since they tend to ingest the most and eat most rapidly.
Despite commonly being called “grain overload,” grain is not the only food source that can cause this condition. However, in a sanctuary setting where residents are fed an appropriate diet, it would be rare for many of the other problematic foods to be available in the amount needed to cause an issue. Fruits, including apples and grapes, as well as sugar beets, potatoes, and bread products can also cause this condition. How much of a particular food is needed in order to cause illness is dependent on the food, what the individual is used to eating, and other factors. Ingestion of grains with a smaller particle size typically results in more severe illness (compared to the same amount of grain of a larger particle size) because it will be broken down more quickly.
Ingestion of carbohydrates, either in excess or by individuals who are not used to such diets, will result in a drop in rumen pH and changes in the rumen microflora. Gram-positive bacteria, which produce lactic acid, will increase (further lowering rumen pH), and other rumen microbes will die. Rumen motility slows, resulting in stasis and mild bloat. This condition can be fatal – prompt intervention is imperative. Be sure to contact your veterinarian immediately if a resident is showing signs of grain overload or if they got into large amounts of grain (or other concerning foods), even if they are not showing signs of illness yet. If you have activated charcoal products, such as Universal Animal Antidote, ask if administration is advised.
Clinical signs of grain overload typically appear within 12-36 hours and vary depending on what/how much the individual ate. Signs include abdominal distension, a “sloshy” rumen (you can often hear the sloshing when standing next to them), depression, colic (including kicking or biting at their abdomen or shifting weight on their hind legs), dehydration, and weakness (which may be so severe that the individual becomes recumbent). The individual will stop eating and may develop diarrhea. Individuals may develop neurologic signs such as ataxiaThe presence of abnormal, uncoordinated movements., head pressing, or seizures.
Be sure to seek immediate veterinary care if an individual is showing signs of grain overload. In some cases, removal of rumen contents through rumenotomy (surgical incision into the rumen) or lavage (using a stomach tube) will be required. Both carry risk, and your veterinarian will determine the best course of action given the specifics of the situation. Transfaunation (ruminal fluid transfer) to restore healthy microflora and fluid therapy to address dehydration and metabolic acidosis are important. Your veterinarian may also prescribe antibiotics (penicillin is commonly used) and thiamine or multivitamin injections, depending on the severity of the illness. They may also recommend certain dietary restrictions while the individual recovers.
Be sure to take measures to prevent grain overload. Make sure all grain is stored out of reach and secured from residents, and if a resident needs supplemental grain added to their diet, talk to your veterinarian about how to safely introduce this. Also, be aware of other risks on your property, such as large numbers of apple trees in or overhanging resident pastures.*
Sources:
UAA (Universal Animal Antidote) Gel | Drugs
Grain Overload In Ruminants | Merck Veterinary Manual (Non-Compassionate Source)
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Infectious Foot Rot (Contagious Hoof Rot)
Infectious foot rot (sometimes spelled “footrot” or used interchangeably with the term “hoof rot”) is a bacterial infection that affects both sheep and goats but tends to be more severe in sheep. Though there are often multiple bacteria involved, Dichelobacter nodosus (formerly Bacteroides nodosus) must be present to be considered true foot rot. The other bacteria most often associated with foot rot, but which in the absence of D. nodosus does not cause true foot rot, is Fusobacterium necrophorum. On its own, F.necrophorum causes interdigital dermatitisDermatitis refers to skin irritation. This may include itchy, dry skin or a rash on swollen, reddened skin. It may also cause the skin to blister, ooze, crust or flake (sometimes referred to as “scald”) but can make the foot vulnerable to infection with D. nodosus. There are numerous strains of D. nodosus with varying degrees of virulence. Some countries, such as Australia, categorize infectious foot rot as benign or virulent based on the strain, but this is less common in other parts of the world, including in the US.
Foot rot typically occurs in areas with periods of warm, wet weather – with spring and fall being the common times for transmission. In addition to wet conditions, overgrown hooves can also make foot rot infections more likely. Some breeds of sheep, such as Merinos, are more susceptible to foot rot than other breeds. Sheep with foot rot contaminate the environment with D. nodosus which can then infect other residents. D. nodosus can only survive for between a few days and a few weeks in the environment, but infected sheep can be carriers for years.
Differentiating between benign foot rot and interdigital dermatitis is difficult, and people sometimes refer to both as “foot scald.” In benign cases, sheep will develop inflammation and necrosisNecrosis is the death of most or all of the cells in an organ or tissue due to disease, injury, or failure of the blood supply. of the tissue between their claws and mild lameness. Benign foot rot typically only affects a few individuals in a flock, whereas virulent strains typically affect numerous individuals. Virulent foot rot often causes severe lameness, separation of the hoof wall, a foul odor, and a black tarry appearance. Individuals with virulent strains may also develop a fever and have a reduced appetite, resulting in weight loss. Foot rot can lead to secondary bacterial infections and fly strike.
Affected individuals often have rot in more than one foot, and both claws are usually affected. If you suspect a resident has foot rot, be sure to get your veterinarian out to examine the individual(s). Foot rot is usually diagnosed based on clinical signs, though, as mentioned above, benign strains may be difficult to differentiate from interdigital dermatitis. Treatment typically involves trimming of the hoof, application of a topical antibiotic treatment (tetracycline is a common one), or medicated foot baths and possibly systemic antibiotics. Please note – there is conflicting information regarding whether or not hoof trimming assists in the healing process or not. Be sure to work with your veterinarian for specific recommendations. Depending on the situation, they may also recommend fully isolating the affected individual or taking measures to prevent exposing other groups of sheep and goats to the bacteria. In severe cases, you may be advised to remove all sheep and goats from certain living spaces temporarily in order to prevent reinfection. Prevention is key – be sure to regularly trim your residents’ hooves, keep indoor living spaces dry and clean, and make sure outdoor areas have adequate drainage.*
Sources:
Footrot | Veterinary Handbook For Sheep, Goats, And Cattle
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Footrot In Sheep And Goats | Purdue Extension (Non-Compassionate Source)
Foot Rot Or Scald: Which Is It? | University Of Maine Cooperative Extension (Non-Compassionate Source)
Contagious Footrot In Sheep | Merck Veterinary Manual (Non-Compassionate Source)
Interdigital Dermatitis (Foot Scald)
Interdigital Dermatitis (OID) is sometimes referred to as “foot scald,” but that term can be confusing because it is occasionally used to describe benign strains of foot rot. Interdigital dermatitis is caused by the bacteria Fusobacterium necrophorum (this bacteria is typically seen in combination with Dichelobacter nodosus, the bacteria that causes infectious foot rot) and often occurs in warm, wet conditions. If the foot is exposed to wet conditions for prolonged periods of time, it can become vulnerable to damage, especially between the claws, which allows bacteria to enter. Sheep with interdigital dermatitis usually develop only mild lameness. Affected sheep will have inflammation of the tissue between the claws, and the skin may be discolored, moist, raw, and sensitive. Individuals with this condition are vulnerable to infectious foot rot. Treatment typically involves limiting their exposure to wet areas and a topical treatment of zinc sulfate. Though sometimes recommended as a treatment, copper sulfate should be avoided due to the possibility of copper toxicity if ingested. In some cases, trimming the wool around the hoof can help the foot to dry out more quickly.*
Sources:
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Foot Rot Or Scald: Which Is It? | University Of Maine Cooperative Extension (Non-Compassionate Source)
Aetiology, Risk Factors, Diagnosis and Control of Foot-Related Lameness in Dairy Sheep (Non-Compassionate Source)
Johne’s Disease
Also known as paratuberculosis, Johne’s disease is a fatal contagious gastrointestinal disease caused by the bacteria Mycobacterium avium subspecies paratuberculosis (MAP). It is believed that all species of ruminants and camelids are susceptible to this infection, with young individuals being most vulnerable. The primary mode of transmission is the fecal-oral route, but it can also be transmitted via colostrum and milk. For more information about this challenging disease, including information regarding diagnostics and ways to mitigate disease spread, check out our full resource on Johne’s disease here.
Source:
Advanced Topics In Resident Health: Johne’s Disease (Paratuberculosis) |The Open Sanctuary Project
Keds
Sheep keds (Melophagus ovinus) are a blood-sucking external parasite of sheep, though they can occasionally affect other species as well, including goats. This parasite is sometimes called “sheep tick,” though it is actually a wingless fly. Keds are about 7mm long – large enough to be seen easily with the naked eye but may be concealed by the sheep’s wool, making observation difficult without looking through their wool. Common feeding areas include the neck, shoulders, chest, sides, and bum, but not typically the back. Keds are spread through direct contact with infected individuals.
Sheep with keds will be itchy, so watch for any biting, scratching, or rubbing. Wool will also become discolored from the keds’ excrement. Severe infestations can result in anemia and weight loss, and keds can transmit certain diseases such as bluetongue. Treatment typically involves shearing, which will remove a large percentage of keds, and a sheep-safe topical treatment. If shearing is not an option due to weather concerns, you can still treat, but you’ll need to make sure to part their wool and get the treatment down to the skin. Permethrin-based products are typically effective, but your veterinarian should be able to recommend an appropriate product that is safe for your residents and can also make recommendations about follow-up treatments depending on the product.*
Sources:
Sheep Keds | Merck Veterinary Manual (Non-Compassionate Source)
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Laminitis
Laminitis, inflammation of the soft tissues of the hoof, is a painful condition that, while more common in equines, can also affect sheep. Laminitis is often associated with diet – sudden access to or overconsumption of concentrates or lush forages; a diet high in protein; or a diet high in grain and low in roughage could predispose a sheep to laminitis. Certain illnesses, such as pneumonia, mastitis, and metritis, can also play a role in the development of laminitis.
Signs of laminitis include lameness, a stiff gaitA specific way of moving and the rhythmic patterns of hooves and legs. Gaits are natural (walking, trotting, galloping) or acquired meaning humans have had a hand in changing their gaits for "sport"., feet that are noticeably hot, and pain and sensitivity at the coronary band. You may hear the individual grinding their teeth due to pain, and they may develop a fever. Sometimes only the front feet are affected, but in more severe cases, all four feet are affected. Without treatment, laminitis can become a chronic condition resulting in changes in the shape of their claws and a difference in height between the inner and outer claws. In chronic cases, knee walking is common, and hoof material is often very hard, making it difficult to trim.
Be sure to work with your veterinarian if you suspect one of your residents has laminitis. In acute cases, in addition to analgesics (typically an NSAID), it’s important to also identify the underlying cause (and correct/treat it if possible). In chronic cases, frequent, aggressive hoof trimming will be necessary. Your veterinarian can guide you in how often and how aggressively to trim their feet. While not all laminitis is associated with dietary issues, ensuring your residents are on a proper diet and avoiding sudden changes to their diet is helpful in preventing laminitis as well as a host of other health issues. If someone needs supplemental grain, be sure to introduce this slowly.
Pay close attention to your residents’ hooves during routine health checks, and contact your veterinarian if you notice abnormal growth or changes to the shape of the hoof.*
Sources:
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Lice
There are multiple species of sheep lice, including Bovicola ovis, a chewing louse that feeds on skin cells and debris, and Linognathus pedalis and L. ovillus, which are sucking lice that feed on blood. While lice tend to be species-specific, it is possible for sheep who live with goats to become infected with some types of goat lice and vice versa. In regions with cold winters, lice infestations tend to be more of a cold weather issue.
Different lice species affect different areas of the body (though as infestations become more severe, lice may spread to other areas). For example, B. ovis is typically found on woolen parts of the sheep, especially their back; L. pedalis (sheep foot louse) typically affects hair-covered areas of the foot and leg, but can spread to the abdomen and scrotal area; and L. ovillus (sheep face louse) typically affects the face and other hair-covered areas. Early signs of lice infestations include itching and rubbing, which is often noticed before lice can be easily found during a health checkThe Open Sanctuary Project uses the term "health check" to describe health evaluations performed by caregivers who are not licensed veterinarians. While regular health checks are an important part of animal care, they are not meant to be a replacement for a physical exam performed by a licensed veterinarian.. Sheep with lice infestations may have damaged, raggedy, or missing wool/hair due to itching and rubbing. Foot lice infestations can also cause lameness. Severe sucking lice infestations can result in anemia.
Lice are transmitted via direct contact with infected animals and via infected fomitesObjects or materials that may become contaminated with an infectious agent and contribute to disease spread. While it is possible to see lice with the naked eye, it can be very difficult to find them in the wool until there are many lice present. Individuals with compromised immune systems may be more severely impacted than other residents, but even if you can only find lice on one member of the flock, you should plan on treating the entire flock. Treatment typically includes shearing (if the weather permits), as this will reduce lice populations and will also make topical treatments more effective. Your veterinarian can recommend a treatment based on the type of lice and also the specifics of your region; insecticide resistance is becoming an issue in some parts of the world and may impact the recommended treatment plan.†
Sources:
Sheep Lice | Prime Facts (Non-Compassionate Source)
Lice | Sustainable Control Of Parasites (Non-Compassionate Source)
Sheep Lice Spread And Detection | Government Of Western Australia (Non-Compassionate Source)
Lice In Sheep And Goats | Merck Veterinary Manual (Non-Compassionate Source)
Biology Of Sheep Lice (Bovicola ovis) | Lice Boss (Non-Compassionate Source)
Sheep Lice | Parasitipedia (Non-Compassionate Source)
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Listeriosis
Listeriosis is most often the result of an infection caused by the bacteria Listeria monocytogenes, though, in sheep, disease from L. ivanovii infection is also possible. This bacteria can be found in soil, water, and vegetation. Many species of animals can be affected by this disease and can shed the bacteria in their feces, even if they are not showing clinical signs of disease. This disease occurs more frequently in the winter and spring, and sheep typically become exposed by ingesting plants contaminated with infective soil or feces. Listeriosis is often associated with feeding poor-quality silage (partially fermented forage) but can also be caused by ingesting moldy hay or rotting vegetation.
Not all individuals carrying this bacteria will show clinical signs of disease, but when clinical signs are present, they typically manifest in one of the following ways: encephalitis, which is the most common manifestation, abortion, septicemia, mastitis, or ophthalmitis. Initial signs of the encephalitic form include depression and inappetence. Individuals often appear disoriented and may walk in circles towards their affected side (which is why listeriosis is sometimes called “circling disease”). They may develop facial paralysis on the affected side with a droopy ear and eyelid and loose lips. They may drool excessively, and there may be food stuck in their cheek on the affected side because chewing is difficult. In severe cases, the individual may show more severe neurological signs, in which case the prognosis may be poor even with treatment.
If you think a sheep is suffering from listeriosis, it’s critical that you get a veterinary evaluation, as prompt, aggressive antibiotic treatment is imperative for successful recovery. If the individual is unable to eat or drink normally, supportive care will also be necessary. Individuals with listeriosis should be isolated from other residents. Listeriosis is a zoonotic disease, though most healthy humans do not become seriously ill. Humans most at risk of listeriosis are newborns, the elderly, and those who are pregnant or immunocompromised. Speak with your human physician if one of your residents has been diagnosed with listeriosis and you have concerns about your risk of contracting the disease.†
Sources:
Overview of Listeriosis | Merck Veterinary Manual
Listeriosis In Sheep And Goats | Michigan State University Extension
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Listeriosis In Ruminants And Human Risk | Purdue University College Of Veterinary Medicine (Non-Compassionate Source)
Liver Flukes
Though it is not the only species that can affect sheep, Fasciola hepatica (Common Liver Fluke) is considered one of the most important flukes that affect small ruminants. This parasite has a very complicated life cycle involving a semi-aquatic “mud” snail as an intermediate host. Because both the snail host and the parasite require wet habitats and temperatures above 50° F (10° C), liver flukes tend to be a seasonal and regional concern. However, when conditions are right, it is possible for a large number of these parasites to be present.
Because of its complexity, we’ll look at a simplified overview of the life cycle of F. hepatica (which is similar to other Fasciola species). Infected individuals pass eggs in their feces. Eggs only hatch in water, and once hatched, miracidia (ciliated larva) can only survive for a few hours. They immediately seek out an intermediate mud snail host, and once inside the snail, asexual development and multiplication occurs. Eventually, infective cercariae (free-swimming larva) emerge from the egg (with timing depending on environmental temperature and moisture). Cercariae then migrate to wet vegetation where they encyst and become metacercariae. Individuals become infected by ingesting metacercariae, and following infection, young flukes eventually migrate to the liver.
F. hepatica infection can cause acute or chronic disease. Migration of large numbers of young flukes causes acute fascioliasis, which can quickly become fatal. Signs of acute fascioliasis include refusal to eat, depression, weakness, labored breathing, anemia, abdominal pain, peritonitis, and dry feces. If individuals are not vaccinated against clostridial diseases, they can develop a co-infection with Clostridium novyi (causing infectious necrotic hepatitis or “black disease”), which results in sudden death. Chronic fascioliasis is the result of adult flukes in the bile ducts. Signs include anemia, bottle jaw, and weight loss. Heavy chronic infections can be fatal.
Diagnosis of F. hepatica infection in living residents can be difficult but can be easily accomplished during a post-mortem examination if infection is suspected in a deceased resident. While eggs can be detected in a fecal test, a negative result cannot rule out infection. Your veterinarian can make specific recommendations regarding diagnostics if infection is suspected or if the parasite is prevalent in your area. They can also make treatment recommendations. Anthelmintic resistance can further complicate treatment. The timing of treatment is also important, so be sure to work closely with your veterinarian to ensure the most appropriate treatment plan is implemented. Preventing residents from accessing wet areas where mud snails may be present can help limit exposure to these parasites, particularly during times of year when the risk is high.
As mentioned earlier, F. hepatica is not the only fluke species that can affect sheep. One of the other species of note is Fascioloides magna, whose definitive hosts include deer, elk, and moose. Even one of these flukes can cause extensive damage and death in sheep due to “aimless wandering” through the liver. Diagnosis and treatment are difficult. In areas where conditions are right and definitive hosts are present, you’ll want to work closely with your veterinarian to establish a plan to reduce your residents’ risk of this infection.*
Sources:
Fasciola Hepatica In Ruminants | Merck Veterinary Manual
Liver Fluke | Sustainable Control Of Parasites
Life Cycle Of The Liver Fluke: Fasciola Hepatica | David Barlow
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Large Animal Internal Medicine 5th Edition | Bradford P. Smith (Non-Compassionate Source)
Diagnosis, Treatment, And Prevention Of Common Small Ruminant Parasites | Dr. Mary Smith, DVM (Non-Compassionate Source)
Lungworms
There are multiple lungworm species that can affect sheep and goats – the most important being Dictyocaulus filaria, Muellerius capillaris, and Protostrongylus rufescens.
D. filaria is the most pathogenic of the lungworm species that can affect sheep. Unlike the other two species, it has a direct life cycle. Infection most often occurs in young sheep, but adults can also be affected. Female D. filaria lay eggs in the lungs, which are then coughed up, swallowed, and hatch into first-stage larvae before being passed in feces. Larvae develop into infective third-stage larvae on the pasture – how quickly this occurs depends on environmental factors. Sheep become infected by ingesting infective larvae while grazing. The larvae continue their development inside the host and travel to the lungs to start the process again. Signs of D. filaria infection include coughing, nasal discharge, elevated respiratory rate, labored breathing, chronic fever, poor appetite, and weight loss.
M. capillaris is the most common lungworm species to affect sheep and is also the least pathogenic. In fact, many infections do not cause clinical disease in sheep (goats are typically more severely affected). M. capillaris has an indirect life cycle and requires an intermediate snail or slug host. Female M. capillaris lay eggs in the lungs that hatch into first-stage larvae. These larvae are coughed up, swallowed, and passed in the feces. Larvae then penetrate their intermediate host and develop into infective third-stage larvae. Sheep become infected by ingesting snails or slugs containing infective larva while grazing. The larva continues to develop and travels back to the lungs to start the cycle again. Signs of M. capillaris include coughing, labored breathing, and failure to gain weight.
P. rufescens infections are typically subclinical or mild, but serious illness is possible. P. rufescens is rare in North America. This parasite has a similar life cycle to M. capillaris. Infection can cause diarrhea, weight loss, mucopurulent nasal discharge, elevated respiratory rate, and increased respiratory sounds.
Diagnosis of lungworm infections can be difficult. In addition to looking at clinical signs, a fresh fecal sample can be evaluated using the Baermann technique to identify larvae. Fecal samples should be fresh, and it’s best to collect feces directly from the rectum. Damage from lungworm infections can lead to secondary infections. Your veterinarian can recommend an appropriate treatment based on the species of lungworm and also your sanctuary’s overall parasite management plan. M. capillaris may require higher doses or repeat treatment in order to kill immature worms. If lungworm is suspected in a resident who has died, diagnosis can be made during a post-mortem examination.*
Sources:
Overview Of Lungworm Infection | Merck Veterinary Manual
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Large Animal Internal Medicine 5th Edition | Bradford P. Smith (Non-Compassionate Source)
Mange
Mange is a skin condition caused by a mite infestation. There are multiple types of mange that can affect sheep, including sarcoptic, chorioptic, and psoroptic mange. Diagnosis may involve a skin scraping and microscopic identification of the mite, but in some cases, your veterinarian may recommend a certain treatment based on clinical signs alone and will monitor their response to treatment in order to help confirm the diagnosis. Treatment depends on the type of mange and, in some cases, the severity of clinical signs, and typically comes in pour-on, injectable, and topical formulations.
Sarcoptic Mange
Caused by the burrowing mite Sarcoptes scabiei var ovis, sarcoptic mange is rare in sheep in the US. S. scabiei var ovis typically infests areas of the face and head that are not covered in wool, causing crusty skin and intense itchiness. Because this mite burrows into the skin, they can be difficult to find on skin scrapings. A negative skin scraping does not rule out the possibility of sarcoptic mange. S. scabiei var ovis is spread primarily via direct contact with infected individuals and is zoonotic. While it is not the same mite as the one that causes scabies in humans, S. scabiei var ovis can be transmitted to humans but will be self-limiting.
Chorioptic Mange
The Chorioptes mite does not burrow under the skin and instead lives on the skin’s surface. Chorioptic mange often affects a sheep’s feet and legs, especially the area under the dewclaws, but can also affect the scrotum. Crusty and scaly skin, alopeciaAlopecia is the loss of hair, wool, or feathers., redness, and itchiness are common signs. Individuals may be seen stomping or chewing at their feet due to itchiness and discomfort.
Psoroptic Mange
Caused by Psoroptes ovis (also called the sheep scab mite), psoroptic mange is highly contagious and can cause serious disease. It has been eradicated from sheep in the US, Canada, and New Zealand, but is an issue in many other countries. Clinical disease from P. ovis is worst in the fall and winter. These mites infest wool-covered areas of the body and cause intense itching and scaly, crusty lesions on the skin. Sheep will scratch, bite, and lick infested areas to try to relieve the itching. As a result, self-trauma and wool loss are common. Secondary bacterial infections are also possible. Without treatment, infestations can result in anemia, emaciation, and even death.†
Sources:
Scabies | Centers For Disease Control And Prevention
Mange In Sheep And Goats | Merck Veterinary Manual (Non-Compassionate Source)
Mites | LivestockAnother term for farmed animals; different regions of the world specify different species of farmed animals as “livestock”. Veterinary Entomology (Non-Compassionate Source)
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Mastitis
Mastitis is inflammation of the udder and can be caused by injury, stress, bacterial infection (often caused by Streptococcus sp., Staphylococcus sp., Pasteurella sp., or coliforms, such as E. coli), and can also be the result of unsanitary housing. Additionally, OPP can also manifest as mastitis. Individuals with clinical mastitis will often have a hot, swollen, and painful udder. Other symptoms of clinical mastitis include fever, inappetence, and depression, and mothers may not let their babies nurse due to the associated pain. Babies will need to be bottle-fed to ensure they are getting the nutrients they need. In cases of severe mastitis, the udder may become bluish in color due to issues with blood supply – this is often referred to as “blue bag”. Mastitis can also be subclinical. In this situation, the individual usually appears healthy, but their udder may have firm masses in it, and if they are lactating, they will have a reduction in milk. Be sure to contact your veterinarian if you suspect one of your residents has mastitis. They can recommend diagnostics to determine the cause and appropriate treatment, which typically consists of injectable or intramammary antibiotics and pain medication. In some cases, mastectomy may be advised.†
Sources:
Mastitis In Ewes And Does | Maryland Small Ruminant Page (Non-Compassionate Source)
Mastitis In Small Ruminants | IFAS Extension University Of Florida (Non-Compassionate Source)
Overgrown Hooves
While some sheep may naturally wear down their hooves through regular activity, many sanctuary sheep residents will need their hooves trimmed to prevent them from becoming overgrown. Overgrown hooves can predispose residents to other issues, so keeping your residents’ hooves properly trimmed is integral to their health. How often an individual needs their hooves trimmed depends on many factors such as their genetics, diet, other health issues, and their environment. We recommend checking sheep hooves during routine health checks and trimming as needed. However, older residents, individuals who are less active, and individuals with laminitis may need more frequent trimming. If you notice that someone’s hooves become very overgrown between health checks, you should implement a more frequent hoof trimming schedule for them.
Without regular trimming, the hoof wall will grow past the soft sole of the sheep’s foot and begin to curl over on their toe, which can create painful walking conditions and trap dirt tightly against the area between the sole and hoof wall. It will also begin to grow on the heel, creating an uneven surface for the sheep to walk on. If a sheep seems to show difficulty or reluctance walking, start by checking their feet. They might be far past due for trimming by that point! If their hooves are significantly overgrown due to a lack of hoof maintenance, such as in the event of a newly rescued sheep, you may need to spread trimming out over a couple of sessions. During the first trimming, you can work to bring each claw closer to a reasonable length and shape, and then come back a few days or a week later to do the finishing touches. If you encounter someone whose hooves are significantly overgrown or misshapen and you are unsure of how to address them, be sure to consult with your veterinarian for assistance. For more information on hoof trimming, check out our resource here.†
Source:
How To Trim A Sheep’s Hooves | The Open Sanctuary Project
Ovine Progressive Pneumonia (OPP)
OPP is a slow-developing retroviral disease. Afflicted sheep may have difficulty breathing and/or walking, may lose weight, and may develop paralysis or mastitis. To learn more about this condition, check out our resource on OPP here.
Parelaphostrongylus Tenuis (Meningeal Worm, Deer Worm, Brain Worm)
Parelaphostrongylus tenuis is a parasitic worm whose natural host is the white-tailed deer. Sheep, as well as goats and camelids, living in areas with white-tailed deer populations can also become infected by this parasite but are considered aberrant or unnatural hosts. In these species, the parasite can cause significant issues not typically seen in white-tailed deer. P. tenuis requires an intermediate terrestrial snail or slug host. Natural and aberrant hosts become infected by ingesting infective snails or slugs.
There are two common manifestations of this parasitic infection – one presents as neurological issues and the other presents as skin issues. Neurological symptoms typically start with slight weakness or dragging of one or both hind legs, which can then develop into more severe ataxia and even hind limb paralysis. When presenting as a skin issue, symptoms include excessive itching and hair loss – typically in vertical stripes on the body. In rare instances, an affected individual may develop a head tilt, walk in circles, have rapid eye movements, and have a hard time chewing.
Presumptive diagnoses are made based on clinical signs and exposure risk – a fecal test will not detect P. tenuis in sheep. In some cases, examination of the cerebrospinal fluid may be recommended to help support the presumptive diagnosis, but this requires anesthesia and will not result in a definitive diagnosis. Absolute confirmation of P. tenuis can only be made during a post-mortem examination. Treatment typically includes a combination of multiple dewormers (often at higher and/or more frequent doses than when used to treat other parasites) and an anti-inflammatory medication. With prompt treatment, even individuals with more severe symptoms can make a full recovery, though some may have residual weakness for the remainder of their lives. If left untreated, paralysis and other neurological symptoms can become permanent.*
Sources:
Meningeal Worm – Deer Worm – Brain Worm | Maryland Small Ruminant Page
Deer Worm Factsheet | Cornell Sheep & Goat Program and Cornell Ambulatory Veterinary Services (Non-Compassionate Source)
Pink Eye
The term “pink eye” is often used to describe infectious keratoconjunctivitisKeratoconjunctivitis is an infectious often epidemic disease that is caused by an adenovirus (especially serotypes of species Human adenovirus B and Human adenovirus D of the genus Mastadenovirus) and is marked by pain, redness and swelling of the conjunctiva, edema of the tissues around the eye, and tenderness of the adjacent lymph nodes. (IKC), but is sometimes used to describe non-infectious eye irritation resulting from dust, wind, hay, grass, or even intense sunlight. Infectious keratoconjunctivitis can be caused by various microorganisms, but the most common are Mycoplasma and Chlamydophila, especially Mycoplasma conjunctivae and Chlamydophila pecorum. Initial signs of infectious keratoconjunctivitis typically include squinting, watery eyes, and sensitivity to light. The affected eye(s) will be red and inflamed. As the condition progresses, they may develop thick discharge from the eye, and the eye will become cloudy. In some cases, individuals may develop a corneal ulcer or become temporarily or even permanently blind. Be sure to contact your veterinarian if one of your residents is showing signs of an eye issue, as prompt treatment is imperative.
Because of the contagious nature of infectious keratoconjunctivitis, individuals showing signs of this disease, as well as those who have had direct contact with them, should be isolated from residents who have not been exposed. The disease can be spread via direct contact with infectious eye discharge but can also be spread via fomites and flies. Most causes of infectious keratoconjunctivitis in sheep and goats are bacterial and typically respond to treatment with tetracycline drugs, but please defer to your veterinarian for specific guidance. Treatment often includes application of an antibiotic eye ointment after cleaning away any discharge or crusts, but they may also prescribe systemic antibiotic treatment. In some cases, your veterinarian may determine that more advanced treatments are necessary.
While individuals are healing, it is important to protect them from eye irritants such as flies, wind, dust, and rough hay or pasture and to house them in a shady area. If the affected individual has become blind, they may need additional accommodations to keep them calm and comfortable, and you will want to make sure they are easily able to find food and water. Depending on the underlying cause, individuals can continue to spread infection for months after they have stopped showing signs of illness. Your veterinarian can recommend diagnostics to determine the cause and can make specific recommendations based on the results.†
Sources:
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Contagious Keratoconjunctivitis (Pinkeye) | Maryland Small Ruminant Page (Non-Compassionate Source)
Pizzle End Rot
Pizzle end rot, or ulcerative posthitis (sometimes also called “sheath rot”), mostly affects neutered males. It can be the result of a high protein diet, such as from grazing on lush pastures, but can also have a non-dietary cause. High protein intake causes the concentration of urea in the urine to increase. Bacteria that are part of the local flora, such as Corynebacterium renale, break down the urea, releasing excess ammonia. The ammonia then leads to irritation and ulceration of the prepuce. Once the skin is ulcerated, it is vulnerable to bacteria. Alternatively, if an individual’s hair or wool is long and covers their prepuce, it will become soaked with urine, resulting in irritation and an environment that is conducive to bacteria growth.
Pizzle end rot manifests as inflammation and scabbing of the prepuce, which can range from mild to severe, and in severe cases, the inflammation or scabbing can interfere with urination. Treatment of mild cases of pizzle end rot may only require cleaning and application of an antibacterial ointment. More severe cases may require veterinary involvement to evaluate the extent of the infection, debride the area, and prescribe systemic antibiotics and pain medication. During fly season, pizzle end rot can attract flies, resulting in fly strike, so be sure to monitor the area closely and take steps to protect the area from flies. It’s important to identify the underlying cause and consider what changes can be implemented to prevent the issue from recurring. If caused by long hair or wool, regularly shaving the area around the prepuce or frequently monitoring for signs of urine build-up and cleaning the area as needed can help prevent future issues.†
Sources:
Pizzle Rot In Sheep | Ontario Ministry Of Agriculture, Food, And Rural Affairs (Non-Compassionate Source)
Enzootic Posthitis And Vulvitis In Sheep And Goats | Merck Veterinary Manual (Non-Compassionate Source)
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Pneumonia
While far from being the only respiratory disease that affects sheep, pneumonia is one of the most common conditions that affects their lower respiratory tract. Pneumonia can be caused by various pathogens, including bacteria, viruses, and parasites, or even a combination of these. Some potential causes of pneumonia include the pneumatic form of OPP, internal CL abscesses in the lungs, and lungworm infections, though there are numerous other bacteria and viruses that can cause pneumonia in small ruminants.
Certain conditions can increase an individual’s risk of developing pneumonia. Poor ventilation, unsanitary living spaces, and high levels of dust (such as from dusty bedding or dusty hay) can put residents at risk and should be avoided. Additionally, extreme temperature fluctuations can also put residents at risk, and some sanctuaries note that pneumonia tends to be a concern when the seasons change. Individuals can also develop aspiration pneumonia if they inhale food, water, or medications into their airways. Inappropriate administration of large amounts of liquid medication (such as dewormers) is a common cause of aspiration in adults (bottle feeding is a common cause in neonates).
Be sure to watch residents closely for signs of pneumonia which include dullness, lethargy, coughing, fever, labored breathing, an elevated respiratory rate, and nasal discharge. Be sure to contact your veterinarian if one of your residents is showing signs of pneumonia. It will be important that they evaluate the individual and run any necessary diagnostics in order to determine the underlying cause. Based on their findings and diagnostic results, they can determine an appropriate treatment plan. In the case of a contagious cause, your veterinarian can also make recommendations in regard to protecting other residents.*
Sources:
Common Diseases And Health Problems In Sheep And Goats | Purdue Extension (Non-Compassionate Source)
Sheep Nasal Bot Fly
Oestrus ovis, often called the sheep nasal bot, sheep nose bot, or simply the sheep bot, is found worldwide but is most common in warm climates. The female fly deposits small (less than 2mm long), clear-white larvae in the host’s nostrils. These larvae then travel into the nasal cavities and sinuses, where they develop over a period of 1-10 months before returning to the host’s nostrils. The host sneezes the mature larvae out of their nostrils, and larvae then drop to the ground to pupate in the soil.
Adult flies attempting to deposit larvae will cause agitation in sheep, who may be seen running in an attempt to get away from them or may keep their nose close to the ground. When flies are very active, sheep may huddle together in a circle with their heads facing inward and their noses down in an attempt to protect themselves. Other signs of agitation from adult O. ovis flies include head shaking, head rubbing, and foot stomping. The presence of larvae causes irritation to nasal passages and sinuses, resulting in profuse nasal discharge, which starts out as clear mucus and then becomes mucopurulent and may be tinged with blood. Other symptoms include sneezing fits, nose rubbing, and reduced airflow through the nareseither of the pair of openings of the nose or nasal cavity. O. ovis infestations can lead to bacterial rhinitis or sinusitis and, less often, interstitial pneumonia. Often, clinical signs are enough for your veterinarian to make a presumptive diagnosis, and response to treatment can help confirm. Ivermectin is effective against all stages of O. ovis larvae.*
Sources:
Sheep Nose Bot | Merck Veterinary Manual
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Large Animal Internal Medicine 5th Edition | Bradford P. Smith (Non-Compassionate Source)
Sore Mouth (Or, Orf)
Sore mouth is a highly contagious viral disease caused by a poxvirus that can affect both sheep and goats. It enters an individual through cuts or abrasions of their skin, and a nursing lamb with sore mouth could also spread the disease to their mother’s udder. Sore mouth symptoms include blister-like lesions in less hairy parts of the sheep’s body, often on their lips and mouth, with the blisters eventually becoming scabs. While adults with sore mouth typically continue eating, lambs with severe lesions may be reluctant to eat, in which case tube feeding may be necessary (this must be performed by a veterinarian or experienced caregiver to avoid potentially fatal consequences).
There is no treatment for sore mouth, but the condition will usually resolve within 3-6 weeks, barring any complications. In some cases, topical or systemic antibiotics may be recommended to address secondary bacterial infections. While this disease is most common in younger sheep and goats, adults can also become infected. Immunity after infection typically lasts 2-3 years, though, after the initial infection, any subsequent infections tend to be less severe. Sore mouth can be spread to humans (though it manifests differently in humans, resulting in a single lesion, often on the hand), so it is imperative that anyone interacting with an individual with sore mouth wears gloves and other protective coverings. Sheep and goats with sore mouth could continue to spread the disease for weeks after lesions have healed, and individuals can be carriers of the disease (and spread it to others) without ever showing symptoms.†
Sources:
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Contagious Ecthyma – Commonly Known As Orf | Ontario Ministry Of Agriculture, Food, And Rural Affairs (Non-Compassionate Source)
Tapeworms
Tapeworms are long, flat, segmented worms that live in the intestinal tract of their host. The most common tapeworm that affects sheep and goats is Moniezia expansa. Tapeworms require an intermediate host, and in the case of the species that affect sheep and goats, the intermediate host is a pasture mite. Pastures contain millions of these free-living mites, which are regularly ingested by sheep and goats while grazing. They become infected by ingesting mites containing tapeworm larvae. Larvae will then continue developing in the host’s small intestine. Tapeworms attach to the wall of the small intestine and absorb nutrients through their skin. Tapeworms are constantly creating additional segments, and mature tapeworms can have hundreds or even thousands of segments.
Tapeworms shed their segments, which are full of eggs. You may find segments in your resident’s feces or you may even see stands of many segments being passed by your residents. In addition to seeing segments, tapeworm eggs can be identified during a fecal exam, but because eggs are not evenly distributed in the feces, the egg count cannot be used to estimate the severity of the infestation. It’s possible for a fecal exam to come back negative for tapeworm eggs despite the fact that the individual has been seen passing tapeworm segments.
There seems to be some debate as to whether or not tapeworm infestations in sheep and goats require treatment or not. If one of your residents has tapeworms and also appears ill, we recommend working with your veterinarian to discuss treatment options and also to assess if there is an additional issue going on (such as another parasitic infestation, like barber pole worm). Be sure to work with your veterinarian to establish an overall parasite management strategy and to make dewormingThe act of medicating an animal to reduce or eliminate internal parasites, either prophylactically or in response to illness. decisions that take into consideration all of the parasitic challenges and any resistance issues present at your sanctuary.†
Sources:
Disgusting Tapeworms! | ACSRPC (Non-Compassionate Source)
Tapeworms: Problem Or Not? | Maryland Small Ruminant Page (Non-Compassionate Source)
Tapeworms: Problem Or Not? | MSU Extension (Non-Compassionate Source)
Thiamine Deficiency
Thiamine deficiency is the most common cause of Polioencephalomalacia (PEM) in sheep and goats, though PEM can be caused by other factors such as sulfur toxicosis, salt poisoning, or lead poisoning. While kids and lambs who have not yet begun to ruminate rely on dietary thiamine (vitamin B1), once sheep and goats start ruminating, healthy rumen microflora produce necessary levels of this vitamin. Because it is water soluble, long-term storage of thiamine in the body is not possible. Therefore, if something occurs that disrupts the normal production of thiamine or causes an individual to require higher levels of thiamine than normal, individuals can quickly become deficient. Rumen acidosis, certain plants, and some medications can put an individual at an increased risk of developing a thiamine deficiency.
Symptoms develop quickly and include behavioral changes, blindness, incoordination, head pressing, backward arching of the neck (so that the head is held high or bent towards their back), muscle tremors, seizures, and rapid eye movements. Thiamine deficiency is often diagnosed based on clinical signs, consideration of the specifics of the situation, and response to thiamine replacement therapy (however, response to thiamine can not rule out another cause of PEM, so be sure to talk about this possibility with your veterinarian). Using diagnostic testing to confirm thiamine deficiency is difficult, and most labs are not equipped to run the specialized tests necessary.
Be sure to contact your veterinarian immediately if one of your residents is showing signs of thiamine deficiency – prompt intervention is imperative and includes administration of thiamine. Depending on the severity of symptoms, your veterinarian may recommend the first dose of thiamine be administered intravenously, but adverse reactions are possible, so this should be done by your veterinarian. They may also recommend an NSAID or steroid treatment, and supportive care may also be necessary.
In the US, concentrated thiamine injectable formulas are prescription only. Vitamin B complex formulas that are available at farm supply stores contain much lower concentrations of thiamine and are unlikely to be effective in treating thiamine deficiency. We recommend talking to your veterinarian about keeping thiamine on hand to be used under their guidance.*
Sources:
Polioencephalomalacia in Ruminants | Merck Veterinary Manual
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Polioencephalomalacia | Michigan State University (Non-Compassionate Source)
Urinary Calculi
Urolithiasis, or the formation of urinary calculi (stones or crystals) in the urinary tract, can affect both males and females but is especially common in males and can result in a life-threatening urinary blockage. Urinary calculi often form as a result of dietary issues. Struvite and apatite stones are most commonly seen in sheep eating diets high in grain concentrates, while calcium carbonate stones are more common in sheep who are eating diets containing lots of legumes. There are other types of stones that can be caused by eating plants containing high levels of certain compounds (such as silica). Be sure to talk with your veterinarian about the risks associated with your region and pasture/forage make-up.
One of the more common causes of urinary calculi is an imbalance of calcium-to-phosphorus in the diet. Generally, you should strive for a 2:1 calcium-to-phosphorus ratio. To help prevent urinary calculi, avoid feeding cereal grains (for example, oats and corn), legumes (alfalfa and clover), and grain concentrates as much as possible. While some sources suggest that male sheep can have grain as long as there is ammonium chloride added, long-term supplementation of ammonium chloride puts them at risk of developing metabolic acidosis and decreased bone density. Overall, it’s better to avoid feeding grain unless there is a medical reason for a resident to receive it.
While urinary calculi can develop anywhere in the urinary tract, they can result in a full or partial obstruction when located in the urethra. Males who are neutered at a very young age are more prone to urinary obstruction if they develop a stone because they have a narrower urethra than males who are neutered closer to 5 or 6 months of age. We recommend having a discussion with your veterinarian regarding the best age at which to neuter your male sheep residents, specifically asking about the increased risk of urinary blockages in males neutered at a younger age.
Signs of a urinary blockage include straining to urinate, posturing as if to urinate but not actually doing so (“sawhorse stance”), head pressing, lethargy, inappetence, and signs of pain such as vocalizing, kicking at their belly, and tooth grinding. This is a very painful condition, but some individuals will mask their pain until they are no longer able to do so; therefore, it is important to catch the more subtle signs of concern. If a resident is showing non-specific signs of a potential urinary blockage (such as inappetence, head pressing, or tooth grinding), as long as they are currently stable and alert, it can be helpful to spend a little bit of time watching to see if they urinate (or attempt to urinate) so you can gather more information. If they struggle to urinate, have bloody urine, are seen dribbling only a small amount of urine at a time, or have crystals or sandy deposits on the hair around their prepuce, these are additional signs of a full or partial blockage.
If you suspect a urinary blockage, contact your veterinarian immediately – if left untreated, urinary blockages can result in bladder rupture and, ultimately, death. Because surgical intervention is often required, we strongly recommend anyone with a suspected urinary blockage be hospitalized as soon as possible. However, in the case of a partial obstruction, if the individual is still passing some urine and is up and alert, your veterinarian may recommend evaluating the individual on-site to determine if hospitalization is necessary.
In addition to avoiding foods that are known to cause urinary calculi, make sure residents always have ample access to fresh water and that the minerals you provide offer the proper ratio of calcium-to-phosphorus. Be sure to look at their food sources, minerals, supplements, and water make-up holistically, working closely with your veterinarian to determine if changes need to be made. If an individual develops urinary calculi, be sure to have the stone analyzed so you know what type of stone you are dealing with and can take appropriate measures to prevent future issues, both for the individual and other residents.*
Sources:
Sheep And Goat Medicine, Second Edition | D.G. Pugh And A.N. Baird (Non-Compassionate Source)
Urolithiasis in Large Animals | Merck Veterinary Manual (Non-Compassionate Source)
Urolithiasis in Small Ruminants | American College Of Veterinary Surgeons (Non-Compassionate Source)
Large Animal Internal Medicine 5th Edition | Bradford P. Smith (Non-Compassionate Source)
White Muscle Disease
White muscle disease is a degenerative disease that can be found in sheep and goats as well as other large mammals. It is caused by a nutritional deficiency of selenium, Vitamin E, or both and can affect heart muscle, skeletal muscle, or both. When the skeletal muscle is affected, a sheep may have an arched back, appear to be hunched over, and move very stiffly, though signs can be less obvious, with the individual only having minor stiffness. Sheep with severe white muscle disease may not be able to stand or even sit upright. Lambs with white muscle disease may be too weak to nurse. When the heart is affected, the individual may have a fever, nasal discharge that is frothy and possibly blood-tinged, and will have difficulty breathing. Individuals with white muscle disease may also have a weakened immune system, making them vulnerable to other diseases.
Selenium deficiency tends to be a regional issue, with some areas having selenium-deficient soil, which results in forages that are low in selenium. Adequate levels of vitamin E are typically found in fresh grass and legumes, but in dried hay, vitamin E levels are low. Therefore, sheep who do not have ample opportunities to graze and are primarily fed hay are more at risk of developing a vitamin E deficiency.
If you suspect one of your residents has white muscle disease, contact your veterinarian for evaluation and to discuss treatment options. Selenium and vitamin E levels can be assessed through blood testing, and treatment involves appropriate selenium and/or vitamin E supplementation based on your veterinarian’s recommendations. While commercial products containing both vitamin E and selenium are available, additional vitamin E supplementation is usually necessary to treat a vitamin E deficiency because of the low levels found in many of these products. Follow your veterinarian’s recommendations. The best prevention is to ensure that sheep have access to nutritional sources that provide appropriate amounts of vitamin E and selenium throughout the year, routinely monitor your residents’ vitamin E and selenium levels through blood testing, and provide appropriate supplementation as needed!†
Sources:
White Muscle Disease In Sheep And Goats | Michigan State University Extension
White Muscle Disease In Small Ruminants | Ohio State University
*Reviewed by a veterinarian in the fall of 2022.
†Reviewed by a veterinarian in September 2023.
