April 30, 2017

Ivermectin, Stongid C2X or Egg Counts? Vet Opinions on Horse Deworming

Two vets give their opinion on the best way to deworm your horse. Both favor the fecal egg count and the Ivermectin/Moxedectin pastes. However, their worming schedules and approach for the pastes and the Strongid C2X daily wormer supplement differ.  Read them both and decide which works best for your horse.

Why is Horse Deworming so important?

There are over 150 different parasites poised to invade the intestines and stomachs of our horses (as well as just about everywhere else in their bodies) .  Contrary to popular belief, many horses that have dangerous parasite levels seem perfectly healthy. Parasite infestation causes loss of nutrients and at its worst leads to colic, intestinal rupture and death.  Deworming properly is as important as clean water and quality feed.

The Fecal Egg Count and Purging to Avoid Resistance

Lindi Kopecko, DVM and Livestock Specialist with Carter Animal Hospital in the Coachella Valley in Southern California:

”The new way to do worming, revamped for a more strategic approach due to the resistance problem is while vaccinating and doing the wellness check. A fecal sample is taken and an egg count (a smear)  performed, more commonly called a FEC.  At this point you see if the horse is a low shedder (egg load), a moderate, or a high shedder.  Ivermectin and Moxidectin (Quest) paste are two of the wormers that don’t appear to have resistance, and treat Bots (fly larvae) as well as Ascarids (roundworm).  Small Strongyls are a parasite that when ingested burrow little holes in the wall of the small intestine where they can become encysted (enclose themselves) these are difficult to pick up with an egg count. Tapeworms are not picked up at all. Praziquantal will kill off about 70% of the Tapeworm population”.

“With the low shedders, treating about twice a year should be enough” says Dr. Kopecko “…with the moderate and high shedders; performing another egg count 10 to 14 days after the first dose will tell you if you have reduced the load (use the Ivermectin Gold first on a high shedder).  The procedure should then be done about 3-4 times a year, depending on the egg count. Achieving a zero count is difficult and only adds to the possibility of acquiring resistance to the Ivermectin and Moxidectin…there will always be bugs”.

Daily Dosing

Jeffrey Smith, DVM of All Valley Equine in Middleton, California, prefers his clients use the Strongid C2X daily dewormer:

“It’s the migratory phase of these larvae that can cause the most problems. Stongid C2X , unlike purge deworming, keeps the worm burden low on a daily basis, and therefore diminishes the damage of the migrating larvae.  You can use the Strongid from 45 days to 90 days to everyday.  Not giving the Strongid every day is a cost-effective option for people as well as being less likely to cause resistance. Follow that up with Ivermectin or Quest (Moxidectin) every six months”.  Alternatively, he recommends the Panacur Powder Pack consisting of 5 consecutive days of administration to aid in the removal of the encysted larvae once a year.  Use this 6 months between doses of once yearly Ivermectin/Moxidectin.


When administering the dewormer paste make sure to rinse out the horse’s mouth. Otherwise they can spit it out easier and be under dosed.  For difficult to deworm horses, put a bit in their mouth; they accept the dewormer much more readily.

Also, be aware Quest is potentially toxic to mini’s, foals, and debilitated horses.  Be careful and avoid use in these animals.

Horses Vary

Certain horses are going to have a high immunity and there shouldn’t be much of a problem.  Others will have low immunity, including foals and older horses, monitor these closely.   Keep your pastures, turnouts and stalls as clean as possible.  Besides keeping the flies and odors at bay it helps prevent the spread of these unwanted creatures.  Having your vet take over the worming practice of your horse is a smart move; it’s more cost-effective in the long run and you’re not playing a guessing game as to who’s living in your horse.

VN:F [1.9.22_1171]
Rating: 10.0/10 (1 vote cast)
VN:F [1.9.22_1171]
Rating: +1 (from 1 vote)
Ivermectin, Stongid C2X or Egg Counts? Vet Opinions on Horse Deworming, 10.0 out of 10 based on 1 rating

Processing your request, Please wait....

Copyright©2011 KC Peters

Speak Your Mind

Copyright © 2017 · TOS · Privacy Policy · Contact Us · FAQ · Log in

Site Design by Blue Newt Design