Todayโs path rounds are on ๐๐๐ญ๐๐ซ๐ข๐!
๐๐ก๐๐ญ ๐ข๐ฌ ๐ข๐ญ?
๐๐๐ญ๐๐ซ๐ข๐ species are long, thread-like worms that live within the abdominal cavity of many species.
๐๐ก๐จ ๐ ๐๐ญ๐ฌ ๐ข๐ญ?
We most commonly see this in horses!
๐๐ก๐๐ญ ๐๐๐ฎ๐ฌ๐๐ฌ ๐ข๐ญ?
The main Setaria species in horses is ๐๐๐ญ๐๐ซ๐ข๐ ๐๐ช๐ฎ๐ข๐ง๐. This species is transmitted primarily by mosquitoes. The mosquitoes feed on an infected horse, and acquire the ๐ฆ๐ข๐๐ซ๐จ๐๐ข๐ฅ๐๐ซ๐ข๐ (larval form) which is free floating in the bloodstream. The microfilaria is then deposited in the next horse that mosquito feeds on, causing an infection. The microfilaria migrate through the bloodstream to reach the abdomen, where they develop into adults and continue the cycle.
๐๐ก๐ฒ ๐ข๐ฌ ๐ญ๐ก๐ข๐ฌ ๐ ๐ฉ๐ซ๐จ๐๐ฅ๐๐ฆ?
Thankfully, most Setaria do not cause significant disease. However, while the microfilaria are wandering around trying to find the abdomen, they sometimes end up in unusual places, such as the heart, lungs, or lymph nodes. This causes a significant immune response, forming a ๐ ๐ซ๐๐ง๐ฎ๐ฅ๐จ๐ฆ๐, a nodule of inflammatory tissue. In some very rare cases, these nodules occur in the brain or eye, causing neurological disease and blindness respectively.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐๐ข๐๐ ๐ง๐จ๐ฌ๐๐?
The diagnosis is based on finding the worms free in the abdomen, and confirming their species through a parasitologist.
๐๐ก๐จ๐ญ๐จ๐ฌ
1-2) Adult worms!
3-4) Microfilaria hanging out in a blood sample from a horse.
๐๐จ๐ฎ๐ซ๐๐๐ฌ
Maxie, G. Jubb, Kennedy and Palmerโs Pathology of Domestic Animals, Volume 2. Sixth Edition.
Photos 1-3 ยฉ Noahโs Arkive contributor Jakowski, Prestwood, Camus licensed under CC BY-SA 4.0.
Photo 4 ยฉ Cells and Smears Veterinary Clinical Pathology Digital Database.
