Merial gave my vet some of it when it first came out. I used it for free, just had to weigh calves twice. It is not labeled for fly control, so they cannot claim that, but it does seem to work. Another cattle farm was given 500 doses also, and they as well as I have noticed a drop in flies. I am thinking horn flies???, not sure of the difference in the kinds.
On my calves, we gave them the wormer at 4-5 months old. The control group received nothing. They had had one round of shots and poured with ivermectin at spring workup.
Merial claimed the ones given LR were 25-75 lbs heavier than the control group. I thought they used some selective numbers to make it work better. Their claim not mine. However, they did have less flies and for the first year in several, I had no eyes to work on that summer.
I have used it for 3 years now. Cows look better. We use another wormer in the fall. LR is good for 150 days., so timing is somewhat important. Cost is around 10 a cow. Forgot what it is like to spend the weekends treating eyes.
Long Range is not for stockers on a intensive grazing program, or cows for that matter. Harrowing pastures, and letting rest for 40 days, breaks the worm cycle also. I will not go back to using regular wormer.
Merial claims comception rates will go up as will weaning weights. Too many variables in my operation to make that claim. Resistance is my biggest worry, we'll just have to see.
I would recommend it, not for just one year, but for several. Don't expect a quick turnaround, see what happens in year 5, then see if you want to continue.
My opinion, gs