This resource has been fully reviewed and updated by a member of The Open Sanctuary Project’s staff as of October 14th, 2021
It can be a challenge to ensure chicken residents have healthy, happy lives after coming to a sanctuary, and there are many different aspects of care to consider each day. Unfortunately, toxic and poisonous hazards are sometimes overlooked in the hustle and bustle of operating a sanctuary. While minor exposure to many of these toxins is unlikely to cause serious problems, large amounts can cause severe health issues and sadly, even death. Many chickens may instinctively avoid toxic plants or avoid them because many are bitter to the taste. However, some toxins are highly dangerous even in small amounts and others are quite palatable. To help ensure you never run into this problem, we have compiled this resource of common plants and other potentially toxic things that have been known to be a problem for chickens.
Plants That Are Toxic To Chickens
Please see The Open Sanctuary Project’s Global Toxic Plant Database and filter Species Afflicted by chickens to see a list of plants across the world that are toxic to chickens. Please note that, while extensive, this list may not contain every single plant toxic to chickens!
Other Potential Chicken Toxins
Blue-green algae are often found in stagnant water when temperatures are high. These algae can be toxic to chickens if they ingest contaminated water. The type of toxin ingested will determine the symptoms.
- Excessive salivation
- Excessive thirst
- Lack of coordination
- Wing and leg weakness, paralysis
- Open mouth breathing
To prevent algae toxicity in chickens and other residents, be sure to clean water sources regularly, especially when the weather is hot. Preventing access to other stagnant or slow-moving water sources such as lakes, bogs, and ponds can also help you keep residents safe.
Botulism can be contracted if turkeys eat or play in contaminated soil, water, or decaying matter, spoiled feed, or by consuming maggots who harbor the toxins. Signs of botulism in turkeys include:
- Ruffled Feathers
- Muscle tremors
- Limp neck
- Droopy eyelids
- Labored breathing
To prevent botulism, be sure to inspect living areas and any water sources for dying or dead animals and promptly and respectfully dispose of any bodies properly, then dump contaminated water, and thoroughly disinfect the water container and refill with fresh water. Prevent residents from accessing stagnant bodies of water!
Cantharidiasis (Blister Beetle Poisoning)
Blister beetles contain cantharidin, a toxic substance that is used as a defense mechanism against predators. While poisoning from these beetles is most concerning for horses and other mammals, they are potentially dangerous to your chicken residents too. While many chickens will avoid eating these beetles, some may be accidentally ingested. Younger birds are more likely to make the mistake of ingesting a blister beetle. They can cause erosive lesions and death if consumed. If you suspect Blister Beetle Poisoning, contact your veterinarian immediately.
Cedar should be avoided in avian living spaces because it can cause respiratory issues. If you use wood shavings for bedding, make sure you are not buying cedar shavings. Pine is also known to contain phenols which could also possibly cause issues for chickens and are best avoided.
Sometimes, copper sulfate is used to treat crop mycosis or digestive issues in chickens. This is generally added to their water. However, copper sulfate in a single dose of >1 g is fatal and should be used with care.
- Watery diarrhea
- Lack of appetite
- Weight loss
- Pale comb
Hardware Disease refers to the injuries that can result from any animal resident eating something they shouldn’t, especially pieces of human-made hardware like nails, screws, and staples. Hardware disease can have devastating effects on any resident. Check out our resource on Hardware Disease prevention here.
Lead was once used in paints and pesticides, and can also be found in natural environmental sources. Even if you have never used any products containing lead, it may still be present in old barn or fence paint, or the soil. Places, where old machinery and leaded gas have been stored, may also have caused the contamination, as would old treated lumber and railroad ties. Chickens may ingest the lead in the environment through the consumption of paint flakes, plant material that has absorbed lead in the environment, and tainted surfaces.
Signs of lead poisoning in chickens are:
- Lack of appetite
- Increased thirst
- Excessive urination
- Greenish droppings
- Downward extended wings
- Young birds may die within 36 hours of ingesting
Having the soil tested at your sanctuary is an easy way to learn if the environment is safe for residents. You can check with a local environmental conservation service, or agricultural extension office to inquire about testing. It is usually a fairly quick and easy process. Prevent your residents from accessing buildings and fences with old paint.
Consult a veterinarian immediately if you suspect a chicken has ingested lead or is beginning to show symptoms of lead poisoning.
Mycotoxins are a toxin produced by molds (fungi) that are harmful to many animals, including chickens. Mycotoxins, specifically aflatoxins can affect chickens through contaminated food or bedding. Moist, warm environments make a perfect recipe for mold reproduction. Aspergillus and Penicillium can produce aflatoxins and can be a particular concern for birds.
- Oral irritation and ulcers
- Skin irritation
- Pale combs and wattles
- Muscle spasms
- Increased susceptibility to infection
Prevention is key in avoiding serious health issues. Luckily, there are many steps you can take to help ensure resident chickens do not suffer the ill effects of mycotoxin poisoning:
- Be sure to keep food, grain, and hay storage areas clean, dry, and cool
- Try to keep food storage areas protected from mice and rats and other wildlife, as they can chew holes in food bags, increasing the likelihood of grain being exposed to damp conditions
- Always feed the oldest sources of food first. Try to use up open food bags within a few weeks after opening in the winter and in even less time in the summer
- Clean any storage bins or cans thoroughly to remove old grain that may get stuck in cracks and crevices
- Check with your food manufacturer or supplier to see if they regularly test for the presence of mycotoxins in grains before mixing food. If they do not, avoid using them and find another supplier
If you are concerned about the possibility of mycotoxin contamination, have your food stores tested. This could be especially important if you have a chicken who shows initial signs of mycotoxin exposure.
Pesticides, Herbicides, And Rodenticides
It may not come as a surprise that herbicides and rodenticides can cause toxicosis in chickens if ingested. If chickens ingest plants or insects that have been sprayed with phenoxy acid herbicides, they can become ill or even die. For this reason, chickens must be not given treated plants or are allowed access to pastures that have been treated with herbicides.
While rats and mice can pose challenges for sanctuaries, it is important to respect them and use compassionate mitigation practices. In addition to the compassion and consideration mice and rats deserve, many rodenticides are anticoagulants and act by preventing the blood from clotting; chickens may find and attempt to eat the poisoned body of a mouse or rat and become poisoned themselves. There are many new and innovative ways to address rodent populations that are more effective and compassionate.
Early treatment is critical. If you suspect a chicken may have ingested any of the poisons above, contact your veterinarian immediately. Blood tests may confirm poisoning.
Polytetrafluoroethylene Toxicosis (Teflon Flu, Polymer Fume Fever)
Polytetrafluoroethylene (PTFE) is found in many household items but those that are intended to be heated are the main source of toxicity. At high temperatures, items containing PTFE can put out highly toxic fumes, resulting in toxicity or even death. Make sure any heat sources you use in resident living spaces, such as a radiant heater or heat lamp, are free of PTFE. We advise against the use of glass bulb heat lamps due to their associated fire risk, but another reason to steer clear is that some are coated in PTFE. Other sources of concern include some hairdryers, heating pads, irons and ironing board covers, computer wires, and non-stick cookware. While polytetrafluoroethylene toxicosis is a concern for any avian resident, be especially vigilant if you share your home with an avian companion, since many household items could contain PTFE.
- Difficulty breathing
- Impaired coordination
- Laying on side
When too much salt is in food or treats or chickens have access to rock salt or salt provided for other animals, they may consume too much, resulting in salt poisoning.
- Abdominal swelling
- Diarrhea (watery droppings)
- Excessive drinking
- Excessive urination
You may notice their bedding or ground covering is wetter and they have watery droppings. Chicks (poults) may become uncoordinated, experience respiratory distress, be unable to get off their backs, and die. If you suspect salt poisoning, remove food or other sources of salt and call your veterinarian ASAP.
Venomous snakebites are not common, but when they occur, should be treated seriously and immediately. If you notice a snakebite, look for others. Snake venom varies by species, and the severity of a bite can also be influenced by the size, age, and number of bites. Most venoms can impair blood clotting and damage the heart, while some others contain neurotoxins. Signs of snakebite may include:
- Swelling at the bite site
- One or more puncture wounds
- Sloughing of tissues near the bite site
- Cardiac arrhythmias
- Impaired ability for their blood to clot
- Rapid, shallow breathing
- Muscle twitches
Seek veterinary care immediately if a chicken is bitten by a venomous snake. Do NOT try to suck the venom out or place a tourniquet. Keep the chicken calm while seeking immediate veterinary care. Depending on the severity of the bite, treatments may include antivenin, pain medications, fluid therapy, wound treatment, tetanus vaccination, and antibiotics. Check out our Compassionate Wildlife Practices At Your Animal Sanctuary for some tips on how to dissuade snakes from your property.
Wood Stains And Paints
Some wood stains and paints can be toxic to residents. Chickens may try to peck at painted or stained surfaces and can become ill if the stain or paint is toxic. When painting or staining fencing or the exteriors of buildings, look for products that are specially made for barns and fencing and listed as animal or “livestock” friendly. If you choose to paint the interior of an enclosure (or if you are painting an area of your home and share your home with a chicken companion), we suggest you opt for a zero VOC paint- some are even labeled “pet friendly.” Chickens are very sensitive to fumes and should be kept away from freshly painted or stained areas until you are certain there are no residual fumes.
See a list of sources here.
Foods That Can Be Toxic To Chickens
- Alcohol: This may seem obvious, but do not give your chicken residents any form of alcohol. Studies have shown that chick embryos that were exposed to ethanol caused developmental and growth issues in chicks after they hatched.1 Studies have also shown that ethanol exposure has been shown to cause damage to the brain, gastrointestinal tract, and other internal organs and organs of the immune system in chickens.2,3
- Anything With Pesticides Or Herbicides: Most vegetables and fruits are sprayed with these chemicals, which are toxic to chickens.4,5,6 Organic produce is safe from these chemicals, but for those foods that have been sprayed, it is important to peel or scrub produce thoroughly to reduce chances of ingestion. Additionally, you should never allow residents access to areas that have been sprayed.
- Avocados: Avocados should be avoided. Leaves, skin, and pits contain higher amounts of the toxin persin with the fruit containing lower amounts. It should be avoided altogether to be safe and prevent poisoning. Guatamalan varieties are generaly considred more toxic than others.4,7 Symptoms of persin poisoning may include weakness, trouble perching, respiratory distress, death of cells around the heart, and possible edema under the skin of the neck and chest.4,7 If not caught early, it could be fatal.4,7,8 If you notice someone has been eating an avocado get them to the vet ASAP. Don’t wait for clinical signs, as it is often too late once they start appearing.
- Chocolate: Chocolate contains theobromine and caffeine and can cause excitability, diarrhea, vomiting, liver, kidney, and lung congestion, heart arrythmia, and death in birds.9,10,11 The darker the chocolate, the more theobromine it contains.9 However, all chocolate contains some amount and should be avoided.
- Citrus Fruits: While there have been anecdotal reports that feeding chickens citrus may cause excessive preening or feather plucking and interfere with calcium absorption, there are multiple studies that show citrus, processed in certain forms, may be used in their diets and may be beneficial to the health of chickens in certain ways.12,13,14,15 However, these are non-compassionate studies and are focued on promoting fast growth, and improving egg production.12 They aren’t considering a chicken’s longterm health in terms of longevity. Many of these studies list the safety of including only a certain amount of citrus byproduct in the diets of chickens, as more than that may cause health issues.12, 15,16 This, of course, isn’t the same as feeding fresh citrus so if you decide to offer them a bit of citrus (many chickens don’t seem to care for it), don’t feed residents citrus frequently and don’t feed much.
- Coffee or Tea: Caffeine has been studied in chickens to see if specific amounts can be added to their diets to improve “performance”.10,17,18 Caffeine, in certain amounts, has been shown to interfere with the immune system and calcium absorbtion, and cause lung issues, heart issues, and deaths.9,11,17,18 Coffee, coffee grounds, beans, tea, and anything with caffeine should be avoided.
- Eggplants: Flowers, leaves and vines and the young green fruit of this plant contain chemicals similar to solanine, found in green potatoes, called solasonine and solamargine.19,20 Solanine is shown to act as a toxin in chickens. 21 Until more is known, it may be best to avoid feeding parts of the plant and the immature, green fruit, to be safe.
- Fruit Pits/Seeds: Apple seeds, and pits in fruits such as apricot, cherry, peach, pear, and plums contain the toxin cyanide.3,9,22 These fruits are generally fine to offer to your chickens as treats, so long as the pits have been removed. While it is unlikey chickens will ingest the larger pits whole, cracked and broken bits of these seeds and pits could increase the risk of exposure. Better safe than sorry! Symptoms of cyanide poisoning could include heart issues, GI distress, weakness, seizures, tremors, stumbling, and respiratory changes, and could result in death.22,23
- Green Potatoes: Green potatoes, particularly the skins and “eyes”, contain solanine, which can be poisonous to chickens.24,25 Solanine is part of a natural defense against insects and fungus, but acts as a toxin in chickens and can cause serious illness and even death in high enough amounts.5,21,26 The gastrointestinal and nervous system are affected with possible symptoms of diarrhea, respiratory issues, convulsions, and paralysis.5,21 The most solanine is found just under the skin, so potato peels are best avoided entirely. Potatoes that have been in the sun will have increased solanine.24,25 Solanine is heat stable, meaning it takes really high temps before the chemical will break down. Research indicates that boiling doesn’t break down the solanine but may reduce it. However, higher temperatures, such as those used in frying, are move effective25,27
- Green Tomato: Green tomatoes, as well as leaves and stems of the plant, contain a solanine-like glycoalkaloid, tomatine, among other chemicals.28 Like solanine in potatoes, tomatine is part of a tomato plant’s natural defense against insects and fungus.28 However, their isn’t much evidence of it being toxic to chickens (or humans, think fired green tomatoes). There is one study where chicken embryos were exposed to different levels of tomatine. Exposure caused skull, eye, and beak deformities, as well as swelling, due to an excess of liquid in the tissues, in the head and neck.29 The amount of tomatine reduces drastically as the fruit matures though there are certain specialty varieties that have higher levels of tomatine than others, even when they are ripe.30 To be safe, avoid providing green tomatoes and any part of the plant and only offer ripe tomatoes as treats.
- Iceberg Lettuce: While not toxic, it is generally known that iceberg lettuce can cause diarrhea if too much is ingested.
- Mango Peels: Although we didn’t find any studies indicating mango to be an issue for chickens, we did come across some interesting information that may be something to keep an eye out for. While there isn’t a lot of information available, it is known that the skin of mangos contain urushiol, a chemical also contained in poison ivy.31,32 Mangoes also contain checmicals referred to as “mangol” that can contribute to skin sensitivity in humans.33 It can act as a skin irritant or cause stomach upset in humans and other species.
- Old Peanuts: Older, damp peanuts commonly become moldy and contain aflatoxins.4 Some symptoms of aflatoxin poisoning include a lack of appetite, incoordination (loss of control over their body), depression, increased susceptibility to infections, spasming, convulsions, and death.4,5,6,34 It is important to err on the side of caution if you aren’t sure about the peanuts you have.
- Onions: Onions contain thiosulphate and other chemicals, which can affect red blood cells and cause anemia and irregularly sized red blood cells in birds in certain quantities.11 In one study, geese died after consuming green onions and research indicated anemia and liver issues were present due to their iingestion.35 In another, a conure presented with a lack of appetite and lethargy then died after ingesting garlic.36 There may also be some medicinal benefits for certain health issues in chickens, but the studies on them are about very specific forms and quantities for specific health conditions.37 Care must be taken and you should discuss any possible treatments with your veterinarian. Choosing not to seek veterinary advice may prove fatal for residents.
- Processed Human Food: Processed foods, especially those that are greasy, salty, or sweet, should be avoided. These foods are not healthy for chickens. Our junk food is also junk food for them. Too much salt, sugar, or fat can cause health problems.
- Raw Beans: These contains phytohemagglutinin (among other things).38,39,40 This is a toxin that affects a number of species in addition to chickens, including humans.41,42 In chickens, eating just a few raw or dried uncooked beans could cause poisoning. Red kidney beans contain the most of this toxin out of all the beans, but others contain the toxin as well.38,42 Studies have shown that raw kidney bean meal causes intestinal and liver changes and pancreas issues, among other health issues in chickens and other species, and could result in death in high enough doses.39,40,41 Avoid any raw beans and dry beans, and be sure any beans have been well-cooked, for their sake AND yours. (Slow cookers are not hot enough to break down the toxin.)41,42 Canned beans have been through a process that has proken down the toxin though they often contain a significant amount of sodium and should be washed thoroughly.
- Rhubarb Leaves: Rhubarb leaves contains oxalate crystals which can be toxic to birds. In birds, ingesting rhubarb leaves can result in signs of acute renal failure and vomiting.11,43,44 Oxalate crystals can also bind with calcium and cause urinary stones.45 While stalks contain some oxalates, it is in significantly lower amounts. Avoid feeding rhubarb leaves to residents.
- Salt: While chickens do need some salt in their diet, too much can cause serious health issues. Excess salt in their diet can lead to salt poisoning.4,5,46,47 Some of the symptoms of salt poisoning are abdominal swelling, diarrhea, dehydration, excessive drinking, excessive urination, weakness, and death.4,5,46,47 You may notice their bedding or ground covering is wetter and they have watery droppings. Chicks may become uncoordinated, experience respiratory distress, be unable to get off their backs and die.47 If you suspect salt poisoning, remove food or other sources of salt and call your veterinarian ASAP.
- Spinach: Spinach also contains oxalates like rhubarb and can interfere with calcium absorption and contribute to egg-binding in addition to potentially contributing to urinary stones and other health issues.11,45,48 Small amounts occasionally may be fine. Discuss with your veterinarian before offering to residents.
- Tobacco: Tobacco contains nicotine and should never be fed to a chicken resident. They should never be around smoke from tobacco products. Ingestion of tobacco can cause a host of symptoms and even death.4,5,11 Signs of nicotine poisoning include hyperexcitability, diarrhea, seizures, and vomiting.4,11 If subjected to tobacco smoke, they can develop respiratory disease, eye diseases, skin conditions, and heart issues and even malformation of the heart, beak, and kidneys.4,11 (Cannabis smoke, while not containing nicotine, can still cause vomiting and depression in birds and should be avoided.)4
- Unshelled Nuts: If you are offering nuts to your residents as a treat, remove the shell first and be sure the nut itself is broken up into smaller pieces if it is particularly larger to prevent choking. Additionally, if you have nut trees or ground nuts on the property, be cautious. Nuts left on the ground and in the weather, particularly damp weather, can contain aflatoxins, which are especially toxic to chickens. Some symptoms of aflatoxin poisoning include a lack of appetite, incoordination (loss of control over their body), depression, spasming, dermal and oral irritation, increased susceptibility to infections, convulsions, and death.4,6,11,34 Some unprocessed nuts also contain potentially toxic chemicals and may be too hard to digest.
- Visibly Moldy Or Rotten Foods: Rotten or moldy foods can contain mycotoxins. These can cause a host of health issues and even death.4,6,11,34 If ingested, you may notice ulcers in their mouth or crusty surfaces inside their mouth.4 A common type of mycotoxin, aflotoxins, are cause by aspergillus fungi. Symptoms from aspergillus toxicosis include lethargy, increased susceptibility to disease, pale combs and wattles, weakness, inappetence, anemia, and abnormal egg shells.34 This is just one of many types of mycotoxins that can hurt your chicken residents. Respiratory issues, coccidiosis, and certain parasites are often associated with them as well.34
Most of the time chickens will avoid things that aren’t good for them, but if food is scarce, or it is included in with other things they normally eat, they can’t always be trusted to steer clear.
While this list isn’t exhaustive, it can certainly help you keep resident chickens safe, healthy, and happy!
Get the word out and share this infographic!
Toxic Foods For Chickens by Amber D Barnes
SOURCES FOR POTENTIALLY TOXIC FOOD SECTION
1. Toxicological Effect Of Ethanol On The Development Of Chicken Embryo In Ova | Pure And Applied Biology (Non-Compassionate Source)
2. Effects Of Ethanol On Health And Performance Of Poultry | Poultry Science Journal (Non-Compassionate Source)
5. Avian Toxicology | Veterinary Toxicology Chapter 53 (Non-Compassionate Source)
6. Poisonings In Poultry | Merck Veterinary Manual (Graphic pictures) (Non-Compassionate Source)
7. Avocado Toxicosis In Animals | The Merck Veterinary Manual (Non-Compassionate Source)
12. A Review On Practical Applications Of Citrus Sinensis By-Products And Waste In Poultry Feeding | Agroforestry Systems (Non-Compassionate Source)
13. The Effects Of Dietary Supplementation Of Citrus Sinensis (Sweet Orange) Peel Extract On Production And Quality Parameters Of Broiler Chicken | Journal Of Applied Animal Research (Non-Compassionate Source)
14. Anthelmintic Effects Of Citrus Peels Ethanolic Extracts Against Ascaridia Galli | Veterinary Parasitology (Non-Compassionate Source)
19. Evaluation Of Solasonine Content And Expression Patterns Of SGT1 Gene In Different Tissues Of Two Iranian Eggplant (Solanum Melongena L.) Genotypes | Food Technology And Biotechnology (Non-Compassionate Source)
21. Solanine Poisoning And Chickens | Student Presentation At Purdue University (Non-Compassionate Source)
26. An Evaluation Of The Embryotoxic Effects Of Blighted Potatoes On Chicken Embryos | Teratology (Non-Compassionate Source)
28. Natural Anti-Microbial Systems | Antimicrobial Compounds In Plants | Encyclopedia Of Food Microbiology (Second Edition) (Non-Compassionate Source)
32. Toxicity And Related Physiological Activity Of Phenolic Substances Of Plant Origin | Journal Of Agricultural Food (Non-Compassionate Source)
34. Food Poisoning And Mould Toxins In Poultry | Bird Health (Non-Compassionate Source)
36. Hemoglobinuric Nephrosis And Hepatosplenic Erythrophagocytosis In A Dusky-Headed Conure (Aratinga Weddelli) After Ingestion Of Garlic (Allium Sativum) | Journal Of Avian Medicine And Surgery (Non-Compassionate Source)
37. Effects Of Phenolic-Rich Onion (Allium cepa L.) Extract On The Growth Performance, Behavior, Intestinal Histology, Amino Acid Digestibility, Antioxidant Activity, And The Immune Status Of Broiler Chickens | Frontiers in Veterinary Medicine (Non-Compassionate Source)
38. Plant Lectins | Cornell: Department Of Animal Science (Non-Compassionate Source)
46. Pathology Of Sodium Chloride Toxicity In Broiler Chicken | Indian Veterinary Journal (Non-Compassionate Source)
SOURCES FOR MAIN TEXT
Blister Beetles | North Carolina State University Extension Service (Non-Compassionate Source)
Poisonings In Poultry | Merck Veterinary Manual (Non-Compassionate Source)
Aflatoxins: Occurrence And Health Risks | Cornell University (Non-Compassionate Sour
Food Poisoning And Mould Toxins In Poultry | Bird Health (Non-Compassionate Source)
Poisonings In Poultry | Merck Veterinary Manual (Graphic pictures)(Non-Compassionate Source)
Polytetrafluoroethylene Toxicosis In Recently Hatched Chickens (Gallus Domesticus) | Comparative Medicine (Non-Compassionate Source)
Postmortem Survey of Disease Conditions in Backyard Poultry | Journal Of Exotic Pet Medicine (Graphic Pictures) (Non-Compassionate Source)