Farnam SimpliFly Feed Through Fly Control for Horses 10 lbs, 160 Day Supply, EPA Approved, Palatable Pellets, Prevents Stable Flies and Manure Breeding

Works on house flies and stable flies. Works really well too. Gnats and horse flies nope. Gnats still are in abundance though maybe have declined but seems they are persistent.Quite possibly has knocked down the gnats. This is all I really see covering the horse manure so I’m hopeful that several season/ years of this will steadily drop their numbers.Summer of 2025 has been our first try of this. And we started late in the season to see a noticeable difference in the house and stable flies. Will probably stop feeding come first frost in NC here and stock up for spring and summer.Highly recommend.

Awesome product. 2 weeks after we started using it we noticed the flies were gone. Saves a lot of money and hassle of using fly spray daily that never really worked. For us it reduced our on farm fly population by 95%. It's wonderful be able to be outside around the horses and yard, and don't forget the barn without the flies attacking us all the time. It also pays for itself by not buying gallon after gallon of fly spray.

I have tried other feed through fly controlproducts and this one just seems to always work.

Surprised at how well this works. Wish I would have purchased years sooner.

There have been feed through, feed additives, and stock blocks, for years that contained insecticides. The story is, the insecticide can't be absorbed by livestock, and so goes right on through, and out, in the animal manure. However, poison is poison, so I refused to use it. Products like this, contain very specific insect growth regulators, that interfere with chitin formation. Livestock does not have chitin, so very unlikely to affect them. This won't kill adult flies, but it will stop them from reproducing on animal waste. I hate flies. They hang on the animals, and get in their eyes. Useless bloodsucking parasites, that are a continual annoyance to what they live off of. Another satisfying fly control item is the, "yellow bag traps" that you hang up, and then add water to. Seeing flies line up on the the trap entrance to get inside, and drown by the thousands is not a bad thing. Problem is the attractant in the bag, smells like a dead animal. Flies love it.

I think it works…it’s hard to tell what things would look like otherwise. The flies still love to be all over the horses but I genuinely don’t see a ton on the piles of poo, which is the point.

Easy to toss in feed. Horse dosent snub his nose at it. I didn't notice any difference with the flies. Maybe I just didn't use it long enough.

Seems to work for some files, not all.