Drylot horses...Worms??

So, I was sitting in class the other day and got to thinking...somehow. No clue how I started thinking about this...

Anywho.

Hypothetically speaking,
If a horse is kept on a drylot (no pasture/grass) and is fed only hay and roughage from a feeder that is up off the ground, then, theoretically, the horse would be at a lesser chance of getting worms, since they would be less likely to injest the larvae.

That's my train of thought.
Now, someone let me know if I'm wrong about this?
Thanks.

Worms could still potentially be a problem from their manure.

My stable has dry lots, and I think it's a bigger problem. Unless you constantly pick them, you'll have problems if you don't keep up with regular worming. We worm every horse, every other month, on the dot. We still have problems with boarders who'll come, and havn't wormed their horse for a month or two. But I think that as long as you're careful it's manageable.

Dry lots---no grass---and feeding up off the ground does minimize parasite reinfection rates. This is because your horse is not eating from the area where parasite larva are.
Grazing---eating grass that is growing in the ground--is the biggest risk factor for parasite infection. Horses are such parasite magnets because they spend so many hours eating grass each day if they are pastured animals. If they aren't eating contaminated grass, then they pick up much fewer parasites. By dry-lotting and feeding everything up off the ground you take out the biggest factor in parasite infections.

Without grass, the risk of tapeworms drops to pretty much nil (there might be some contamination in hay so there is still a possibility) because you have to have grass mites to have tapeworms. No grass=no grass mites.

Strongyles also are transmitted more readily when there is grass in a pasture because somee larva actually migrate up the blades in order that they may be more readily ingested and it's the grazing and picking up feed off the ground that allows for parasite larva to be ingested.

Horses do not genrally eat manure even in a dry lot. The problem with manure arrises when it's in a grazed area because the larva migrate out a short way from the manure and can get washed out or spread out by breaking down of the manure and thus get into the grass so that they can be eaten. In a dry lot, even when manure is left you have minimal "picking up" of forage off the ground so minimum risk of reinfection.

https://www.thehorse.com/ViewArticle.aspx?ID=359

"Infection from stalls or dry-lot paddocks is negligible--clean horse stalls are simply too dry to allow strongyle larvae to develop or persist, and even in a filthy, damp stall, strongyles are unlikely to develop because the ammonia that comes with urine accumulation is extremely toxic to strongyle larvae. Clean and dry or wet and stinky, horses rarely acquire new strongyle infections in confined conditions. " http://www.thehorse.com/ViewArticle.aspx?ID=1523

You are very likely deworming way more than necessary. Do you pick up feces out of the dry lots regularly?

Our horses are on dry lot and wormed every other month as well, how often should they be wormed on a regular basis say like rule of thumb, 3 months, 4 months? They are fed in above ground plastic feeders as well, if I am also likely deworming too much it would be great to cut back and save the money spread out over 8 horses every other month. They were last wormed mid January and are due next week if I stay on the every other month plan, any thoughts will be appreciated and thanks.

For dry lotted horses, start with deworming spring and fall with ivermectin or moxidectin and then in between those two dewormings pull a fecal sample and have a fecal egg count run. (Be sure and wait at least 9 weeks after using ivermectin and 13 weeks after using moxidectin.)

Ryle, Thank you for that info, also is there a danger in worming too often? And is using dimetracious(sp) earth help with worms as well as ticks, lice and flies if used as a light top coating on feed?

The danger with deworming too often is that you expose parasites that are at stages that aren't killed by the drug to that drug and allow them to build up resistance. Also, if you deworm too soon and think that you've been effective when in fact you haven't then you can have an adult population of parasites shedding eggs into your pasture before you deworm again.

Texas A&M did a preliminary study on the use of diatomaceous earth as a dewormer in horses and found no affect on the parasite population in the horse. So, my opinion is that it's not an effective dewormer and definitely shouldn't be used in the place of a sensible strategic deworming program.