Wormers

[farmerjan]

Thanks @Lucky_P .... and I did mean that the worms were more likely to become resistant to the wormer used, not the cows, and that constant use would produce worms that would not respond.
But my making that post was more because of the different comments that pour on wormers do not work.
I agree that you can't deworm out of a nutritional deficiency..... that was the reason we got the vet involved with our situation... the cows were looking good, getting silage and some grain and free choice hay and had looked good when we moved them into this pasture. And it seemed they suddenly started losing weight and some looking poor and some not so much. They acted like they were not interested in the silage cart and we had it checked for mycotoxins... when we took it in the field... it was the weirdest thing he had ever seen... the water was the last "new thing" that was different from the field they had been moved from... but they did not act like there was any stray voltage problems... we watched them go up to drink and there was no hesitation either...
Never really found anything but after worming, they started eating better and the worst ones had the obvious greatest response.

But I agree, that constantly worming does not allow nature to balance it out and does produce worms that will be resistant to whatever is being used.

 

[Lucky_P]

@farmerjan - I wasn't singling you out, but your comment tripped a switch... I've heard many, many people - and not just in regard to wormers in cattle, but also antimicrobials in people, etc. - who have the misunderstanding that animals/people become 'resistant' to anthelminthics or antimicrobials following repeated use, when, in fact, it's the parasites or microbes we're attempting to battle that become resistant, due to continued misapplication, misuse, underdosing, etc.

I won't say that pour-on wormers 'don't' work, but they are the least efficacious mode of administration. as we've discussed previously, studies have shown that about 70% of pour-on drugs that actually get to where they need to be to be effective, are ingested by way of grooming/self-grooming. You need to be absolutely certain that you apply the appropriate dose for the size/weight of the animal, need to make sure that what you're pouring actually ends up on the animal, and not on the ground, and attention to weather conditions, especially rain timing, are considered, in order to better assure decent efficacy.

 

[farmerjan]

We think that there was an infestation of worms there on the residual grass that we had stockpiled.... moved the cows in and some got "hit hard" and obviously ingested more than others. Thing is, this pasture only gets used about 4-6 months... it is at the one barn, and we winter there.. so the worm larvae had to survive for 6 months at least before the cows came back. Had never had that before. Been wintering cows there for 8-10 years so we do not have to travel all over the place to feed and they can get some silage there for the winter. They get moved out in April/May and don't come back until Nov/Dec or so.... depends on the year, summer pasture condition and all that.

The one good thing about doing them while in the headlocks on the silage cart... They cannot move around alot so not as hard to get up behind them and go down their backs. Son is very good at getting the wormer on them on the top line...and he is tall so has a good long arm reach.... and we made sure it was a day when it was not miserably cold and no weather or rain of any kind forecast for 2-3 days after...I took the fecals first then he did the wormer, then when they had quit fighting it so much, and decided to eat, we quietly released the bar lock so they could back out and not think they were "breaking loose"... That was easier than trying to bring them through 2 pastures to get to the alley that leads down to cross the driveway to the barn. We were prepared to do so if need be.

I am sure some do some licking and all that, but it had a chance to get through the hair onto the skin pretty good. Because it had not been a real cold fall/into winter, their winter hair coats were not real thick either.