Todayโs path rounds are on ๐๐ข๐ฅ๐๐ซ๐ข๐๐ฅ ๐๐๐ซ๐ฆ๐๐ญ๐ข๐ญ๐ข๐ฌ!
๐๐ก๐๐ญ ๐ข๐ฌ ๐ข๐ญ?
๐
๐ข๐ฅ๐๐ซ๐ข๐๐ฅ ๐๐๐ซ๐ฆ๐๐ญ๐ข๐ญ๐ข๐ฌ is ๐๐๐ซ๐ฆ๐๐ญ๐ข๐ญ๐ข๐ฌ (inflammation of the skin) caused by ๐๐ข๐ฅ๐๐ซ๐ข๐, which are small worm-like parasites. ๐๐ญ๐๐ฉ๐ก๐๐ง๐จ๐๐ข๐ฅ๐๐ซ๐ข๐ are the most common parasites we see causing this condition!
๐๐ก๐จ ๐ ๐๐ญ๐ฌ ๐ข๐ญ?
This disease occurs in cattle, all over the world!
๐๐ก๐๐ญ ๐๐๐ฎ๐ฌ๐๐ฌ ๐ข๐ญ?
As mentioned, this condition is caused by Stephanofilaria parasites. Depending on where you are in the world, different species of this genus affect cattle. In North America, cattle most commonly get ๐๐ญ๐๐ฉ๐ก๐๐ง๐จ๐๐ข๐ฅ๐๐ซ๐ข๐ ๐ฌ๐ญ๐ข๐ฅ๐๐ฌ๐ข.
These parasites are transmitted by the ๐ก๐จ๐ซ๐ง ๐๐ฅ๐ฒ, which become infected with the parasite after feeding on an infected cowโs skin wound. The fly picks up ๐ฆ๐ข๐๐ซ๐จ๐๐ข๐ฅ๐๐ซ๐ข๐๐, a microscopic worm-like stage, which then develop into larvae within the fly. The larvae are deposited onto the skin of an uninfected cow, where they migrate to the hair follicles. Here, they make themselves a home, develop into adults, and begin producing new microfilariae, allowing the process to continue.
๐๐ก๐ฒ ๐ข๐ฌ ๐ญ๐ก๐ข๐ฌ ๐ ๐ฉ๐ซ๐จ๐๐ฅ๐๐ฆ?
Infection of the hair follicles with these parasites produces circular, hairless scabs or crusts on the animal. Typically we see these on the ๐ฏ๐๐ง๐ญ๐ซ๐๐ฅ ๐ฆ๐ข๐๐ฅ๐ข๐ง๐ (very middle of the belly) in North America. These lesions typically donโt cause too many issues for the cow, other than they might be a bit itchy. However, they can be an issue for producers who want to sell hides, as they make the hide thickened, rough and generally not very pleasant to look at!
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐๐ข๐๐ ๐ง๐จ๐ฌ๐๐?
These parasites can be diagnosed by ๐๐๐๐ฉ ๐ฌ๐ค๐ข๐ง ๐ฌ๐๐ซ๐๐ฉ๐ข๐ง๐ , where a sharp blade is used to scrape the skin surface and gather cells to look at under the microscope. Under the microscope, the adults or microfilariae can be seen!
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ญ๐ซ๐๐๐ญ๐๐?
There is no specific treatment for this parasite, but it does seem susceptible to most of our anti-parasite medications typically used in cattle.
๐๐ก๐จ๐ญ๐จ๐ฌ
1-4) Examples of the round, crusty, hairless lesions on the belly of cattle.
5) A little friend hanging out in a hair follicle!
๐๐จ๐ฎ๐ซ๐๐๐ฌ
Maxie, G. Jubb, Kennedy and Palmerโs Pathology of Domestic Animals, Volume 1. Sixth Edition.
Gerhold RW. Stephanofilariasis in Animals. Merck Veterinary Manual 2020.
Photos 1-5 ยฉ Noahโs Arkive contributors Read, Vet Diag Lab, Chapman, Williams, McGavin licensed under CC BY-SA 4.0.
