Barber's Pole: Deadly internal parasite in sheep and goats

All ages of sheep and goats are susceptible, but the condition is fatal in weaned animals 

Dear Daktari, I have been keeping sheep and goats in a ranching system in Kajiado County for years now. However, the last three years have seen me lose my animals to what my vet calls bottle jaw. The sheep and goats develop a swollen neck. My vet says this is due to stomach worms. Initially, I was deworming by myself and it was effective but the vet advised that I Iet him do it. This together with rotational grazing has reduced the problem to some extent. What are these worms that cause the neck and not the stomach to swell? [Jonathan Memusi, Kajiado County]

Thanks Memusi for the question. This is most likely a roundworm that is common in sheep and goats. Haemonchus contortus is its scientific name; and Haemonchosis is the disease condition it causes. These worms measure up to 2.5 centimetres and occur in the abomasum or fourth stomach of sheep and goats. Female worms have a red and white striped appearance, hence the name ‘barber's pole’ worm. This worm is the most economically significant internal parasite of sheep and goats not only in Kenya but throughout the world. Recently its devastating effects have been worsened by development of resistance to dewormers (anthelmintics). Haemonchosis is a deadly disease if not timely and effectively managed.