Poster for Parasite Control

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I have to admit that I slept in a little bit this morning after last night’s long colic escapade. The colicking horse from last night died early this morning. We couldn’t find any specific or focal lesion on necropsy, just massive, gas-filled intestines.


Hang on to your lunch… This pylorus was completely blocked by bot fly larvae, causing a stomach rupture.

With the day off on an already somber start, a mule with severe colic was being treated when I walked down to the courtyard. This one looked very bad off; the distressed look in his eyes despite medical treatment efforts revealed much about how the story would end. We finally euthanatized him this afternoon. This necropsy was much more revealing than the last. The stomach was completely infested with bot fly larvae. There were not just a few; the pylorus (the outflow tract of the stomach into the small intestine) was completely obstructed by the larvae. Because ingested contents could not leave the stomach through the pylorus and the fact that horses are unable to vomit, the stomach had ultimately ruptured–we found feed material freely floating within the abdomen

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