Dear Dr. McNett,
Dewormer doses, Hoof trimming, Vitamin D supplementation in alpacas, Sheep breeds
Dear Dr. McNett is a weekly column of questions asked by readers. It is published each Tuesday. To submit your small stock questions please post them in the website chat, respond to the email newsletter or send a direct message.
How do I know how much dewormer to give my sheep?
The quantity of dewormer that you use is important. Under dosing is one of many practices leading to the selection of internal parasites that are resistant to our anthelmintics (dewormers). This chart, available from the American Consortium for Small Ruminant Parasite Control (ACSRPC) is the best for dosing by weight, it also contains important notes about safely using the products. If you are guessing your sheeps’ weight, rather than using a scale, round up. For instance, if you think your sheep is 140-150 pounds, use the 150 pound dewormer dose.
How much dewormer is important, but in my mind a more important question is when should I use dewormer. Parasitic resistance to dewormers is leading to scores of previously preventable deaths among small ruminants. It is crucial that we use these products selectively. The ACSRPC website is a phenomenal resource to help shepherds decide when to deworm. Within that website you will find many resources including this free video about parasite management. In my opinion, every small ruminant producer should take the time to watch this video or seek out a similar in-person training.
How many different breeds of sheep exist?
Incredibly, worldwide there are more than 1000 distinct breeds of domestic sheep and 200 of wild sheep. Roughly 60 domestic breeds and 4 wild breeds are present in the United States. Here is the most comprehensive list of domestic breeds that I have found on the internet from one of my favorite sheep websites: sheep101.info
What are your thoughts about Vitamin D supplementation in North American alpacas? Do the benefits outweigh the toxicity risk?
Vitamin D is either synthesized by the skin as a product of exposure to UV light or it is consumed in the diet. Camelids (llamas, alpacas, vicunas, camels) living in places far from the equator like the United States, Canada, United Kingdom and so on, are at risk of Vitamin D deficiency particularly in winter months. Vitamin D deficiency can cause non specific signs like low energy and low appetite in adults. However, in growing animals it can lead to very serious conditions like rickets and other angular limb deformities.
For this reason, supplementation through the winter is usually advised. However, close attention to dosing is very important to avoid toxicity. Vitamin D toxicity can lead to serious kidney problems, low energy, weight loss and going off feed. A veterinarian is the best option for helping you decide when and how to supplement. This guide, from a camelid practice in the United Kingdom also sums up dosing recommendations very nicely.
How often should a sheep have their hooves trimmed?
It depends on the breed, specific genetics, individual hoof health and history, as well as the terrain the sheep are being raised on. When people first procure their sheep, I recommend asking folks who have been raising them how often they are trimming. If this information is unavailable, I recommend checking hooves every 4-8 weeks initially until you get a feel for how often they require trimming. My own flock typically only needs their “nails did” annually at shearing.
Here is a lovely hoof trimming introduction for sheep, goats and cows from folks in New Zealand.
A friendly reminder: I am a veterinarian. I am not your veterinarian. Dear Dr. McNett is not meant for diagnosing or prescribing and is not a replacement for a relationship with a veterinarian who knows you and your animals.
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