This resource was updated in preparation for veterinary review. It was originally published on November 27, 2018.
Barber pole worm (Haemonchus contortus, sometimes called wireworm) is a blood-sucking gastrointestinal roundworm of ruminants and camelids that can cause serious disease, especially in sheep, goats, llamas, and alpacas. In addition to being a very dangerous parasitic disease that can cause life-threatening anemiaAnemia is a condition in which you don't have enough healthy red blood cells to carry adequate oxygen to the body's tissues., barber pole worm is challenging to manage due to the ever-growing issue of anthelmintic resistance (resistance to dewormers). If you have not already done so, be sure to read our comprehensive resource on barber pole worm, which you can find here.
There was a time when it was standard practice to rely much more heavily on anthelmintics (dewormers) and to use them prophylactically (preventatively). At the time, the thinking was that it was best to eliminate as many worms as possible, regardless of whether or not an individual was showing clinical signs of parasitism. Over the years, dewormingThe act of medicating an animal to reduce or eliminate internal parasites, either prophylactically or in response to illness. recommendations, especially for small ruminants, have evolved in response to the growing issue of anthelmintic-resistant parasites. Anthelmintic-resistant barber pole worms are an issue in sheep, goats, llamas, and alpacas, though the degree of resistance and to which drug(s) worms are resistant will vary region by region and also property to property. The overuse of anthelmintics, including previously common practices such as prophylactic deworming or attempting to eradicate barber pole worms by deworming entire flocks/herds at once, accelerates the rate at which resistance develops. To slow resistance, selective, or targeted, deworming is necessary, and this is where the FAMACHA© system comes in. It is a tool caregivers can use to identify individuals who may need to be dewormed.
What Is The FAMACHA© System?
The FAMACHA© system was originally developed in South Africa as a tool to determine which sheep and goats should be selectively dewormed based on their estimated degree of anemia. While not all anemia can be attributed to the presence of barber pole worms, it is the most common cause of anemia in small ruminants, especially during times when they are grazing on pasture. FAMACHA© scoring consists of comparing the color of a resident’s eye mucous membranes with one of five colors on a laminated color chart. Each of these colors correspond to a specific range of the percentage of red blood cells – also known as hematocrit or packed-cell volume (PCV). In theory, the higher the score, the lower the percentage of red blood cells, with a score of 5 indicating severe anemia. FAMACHA© scoring is a relatively simple process (though you should be trained to perform it correctly), and it should not pose any risk (beyond annoyance) to any residents if performed properly. Although the FAMACHA© system was not originally intended for use with camelids, it has been validated as a tool to detect anemia in South American Camelids (including llamas and alpacas). The FAMACHA© system has not been validated for any other species.
When used as originally intended, caregivers score each individual and make decisions about selective deworming based on these scores. Typical FAMACHA© training information recommends that individuals who score a 4 or 5 are always dewormed, and individuals who score a 3 are dewormed on a case-by-case basis, factoring in how they are doing overall and whether or not they are considered a “vulnerable population.” Because training information is geared toward agricultural settings, there is often a focus on individuals in late pregnancy or who have recently given birth and very young individuals when discussing vulnerable populations. However, in a sanctuary setting, vulnerable populations would also include the elderly and those with chronic illness.
While the process of using the FAMACHA© system is not difficult (though it may be time-consuming), it does require proper training from a certified FAMACHA© instructor. You may be able to receive training and purchase a FAMACHA© card from your veterinarian, but you can also find a list of certified instructors in the US, Canada, and Jamaica here. Alternatively, you can receive your certification online. For more information about the online certification process and current online offerings, please refer to the American Consortium Of Small Ruminant Parasite Control (ACSRPC). Proof of certification is necessary to order a FAMACHA© card.
Using The FAMACHA© System In Sanctuary Settings
If you’ve read much about barber pole worm management and using the FAMACHA© system, you’ve likely come across recommendations that do not mesh with compassionate sanctuary care. While the FAMACHA© system in and of itself is harmless and can be a useful tool in assessing which, if any, of your residents may need to be dewormed, discussions of how to respond to individuals who repeatedly score high often mention killing (“culling”) or otherwise removing these individuals from the herd/flock in order to create a group that is more resistant (i.e., carry lower worm burdens) and resilient (i.e., less likely to show clinical signs of infection). Studies show that, in most cases, approximately one third of the individuals in a group carry about 80% of the worms, and some recommendations suggest people consider culling or otherwise “removing” this entire third of the population. We cannot stress this enough: managing parasite issues by killing residents is unacceptable. There may be certain circumstances in which you must consider physically removing a particular individual (or group of individuals) from the herd due to parasite issues (and offering an alternative living arrangement), and there may be times when an individual’s quality of life and prognosis is so poor that euthanasia must be considered, but these situations are very different from agricultural recommendations that suggest killing individuals who regularly have a high FAMACHA© score.
The Limitations Of The FAMACHA© System
FAMACHA© scores are a valuable piece of information, but the system does have its limitations. First, the FAMACHA© system is only intended to screen for barber pole worm infections. While this is the parasite of most concern in many areas, small ruminants and camelids can be affected by other internal parasites as well. Depending on the parasites of concern in your region, you may need a more comprehensive parasite management plan that takes into account additional parasite risks. Similarly, while barber pole worm infections are the leading cause of anemia in areas where barber pole worms are a concern, this is not the only possible cause of anemia. Without other diagnostics, there is no way to confirm that the cause of an individual’s apparent anemia is barber pole worm.
As explained earlier, each FAMACHA© score is intended to correspond to a specific hematocrit range, giving you insight into whether or not an individual is anemic (and to what degree). However, multiple sanctuaries that have used the FAMACHA© system in conjunction with blood testing (specifically, checking hematocrit and total protein levels) have found that, especially in goats, these scores do not always match the corresponding hematocrit level. In fact, we are aware of some individuals consistently scoring high despite having normal hematocrit levels. Making deworming decisions based on FAMACHA© scores is preferable to previously accepted practices of deworming entire herds and flocks, but relying only on the FAMACHA© system to make deworming decisions could still result in deworming individuals who may not currently need to be dewormed. Conversely, certain factors can cause an individual’s eye mucous membranes to be redder than they otherwise would be, thus affecting the efficacy of the test. These factors include eye irritation (such as from hot and/or dusty conditions), fever, infectious diseases of the eye, and diseases associated with blood circulatory failure.
The purpose of the FAMACHA© system is not to assess anthelmintic resistance, so perhaps it is unfair to suggest its inability to do so is a limitation, but it’s important to recognize that making selective deworming decisions is just one part of the equation. Being aware of resistance issues in your region and at your sanctuary more specifically is crucial. Without diagnostic tools to evaluate anthelmintic resistance, developing resistance in parasite populations may go unnoticed until treatments are less than 50% effective and fail to produce an improvement in clinical signs. Using the FAMACHA© system without also routinely checking for developing anthelmintic resistance could result in folks using a dewormer that is not effective. Additionally, while monitoring for anemia is important, it’s equally important that caregivers implement strategies that reduce their residents’ exposure to infective larvae so as to protect them from severe infection and also to reduce the need for deworming (which will help slow resistance).
Incorporating The FAMACHA© System Into Your Parasite Management Plan
Dealing with barber pole worm can be complicated, and there is no one-size-fits-all approach. We strongly encourage folks to work with their veterinarian to create a tailor-made parasite management plan for their sanctuary. In addition to screening tools, this plan should include strategies that reduce your residents’ exposure to barber pole worm larvae (you can read more about this here) and protocols that ensure dewormers are stored and administered properly to ensure their efficacy and to avoid speeding up developing resistance (you can read more about this here).
You should work closely with your veterinarian or an experienced small ruminant parasitologist to determine the most effective way to implement the FAMACHA© system at your sanctuary. Using the FAMACHA© system haphazardly or only when you are concerned about an individual is not going to be as useful as regular scoring. How often you should assess FAMACHA© scores depends both on your region and also the time of year. Your veterinarian will be best able to advise you on an appropriate FAMACHA© scoring schedule. In areas with significant barber pole worm issues, this may mean needing to perform FAMACHA© scoring every 1-2 weeks during the times of year when the worms are most prevalent. Regular scoring (along with proper recording keeping) will give you data to establish a baseline of what an individual’s normal FAMACHA© score typically is (as some residents may have naturally paler mucous membranes than others) and will allow you to recognize any changes in mucous membrane color that could be a sign of anemia due to a barber pole worm infection.
In addition to helping you determine how often you should perform FAMACHA© scoring, your veterinarian can also help you establish additional screening protocols (and can help you make deworming decisions). For example, rather than deworming individuals based on FAMACHA scores alone, you might use the FAMACHA© system to identify individuals who should be further assessed through diagnostic testing. Some sanctuaries perform additional screening (i.e. fecal egg counts and hematocrit tests) on any individual who scores a 4 or 5, as well as performing additional screening on anyone whose score increases by 2 points (i.e., an individual who is typically a 1 but is now a 3). You can read more about some of the tools a sanctuary might consider using to make deworming decisions, along with recommendations about how to incorporate them into your overall strategy here. Keep in mind that daily observation is imperative. It’s important that caregivers are aware of the signs of haemonchosis (clinical illness caused by barber pole worm infection) so that they can closely monitor residents for these signs. This will help you catch issues that develop in the period between FAMACHA© scoring.
SOURCES:
Haemonchus Contortus And Camelids | American Consortium For Small Ruminant Parasite Control
Certified FAMACHA Instructors | American Consortium For Small Ruminant Parasite Control
Why And How To Do FAMACHA Scoring | University Of Rhode Island
Why And How To Practice Integrated Parasite Control For Sheep and Goats | University Of Rhode Island (Non-Compassionate Source)
Why And How To Do FAMACHA© Scoring (Video) | University Of Rhode Island (Non-Compassionate Source)
Why and How To Do Sheep and Goat Fecal Egg Counts | University Of Rhode Island (Non-Compassionate Source)
FAMACHA© Information Guide | American Consortium For Small Ruminant Parasite Control (Non-Compassionate Source)
Do’s And Don’ts Of FAMACHA© Scoring | American Consortium For Small Ruminant Parasite Control (Non-Compassionate Source)
How And Why Resistance To Worm Remedies Develops | Dr. Ray M. Kaplan (Non-Compassionate Source)
