Brown Equine Clinic Week 8

I got called in for a colic surgery last night. On presentation, the 5 month old Standardbred racing foal was throwing herself to the ground and thrashing. She had many scuffs around her head. All of this indicating extreme pain, a fast work up was performed, and she was rushed to surgery with what the doctors thought was an impaction with a possible perforation. 

Upon searching and moving digesta through the small intestine and to the colon, many ascarids were found. Their numbers were high and caused the impaction. These are known as Parascaris Equorum, intestinal round worm of horses. Their prepatent period is 10-12 weeks. The owners were diligent with this expensive filly by deworming at the correct times with pyrantel. The problem is that this roundworm has a migration period where it travels to the lungs, is coughed up and then reswallowed. Pyrantel can only kill what is in the intestine specifically, not parenteral tissues. This is a job for Ivermectin, Fenbendezole or Moxidectin for this specific type of worm. Moxidectin is very effective against the cyst stages but can cause toxicities in foals. Fenbendazole is very useful in ivermectin-resistant strains and safer than Moxidectin. Ivermectin should be sufficient to treat this filly after she recovers. 

None of the intestine was dead and the surgery was quick and easy. 

We are starting her back on a liquid diet (milk and water only) and waiting for her to gain some more strength after surgery to be able to get treated against the worms. The doctor on the surgery mentioned that she has tried to remove the worms manually before but it didn't turn out well for her last patient. It was a longer recovery time and she ran into other complications.