Pour-on dewormers need to be used on a rotational basis.
I thought spring was here, but Mother Nature sure fooled me. She made it snow. The wet, muddy conditions will be hard on those calving, and we can only hope for better weather. Twenty years ago the jury was divided as to whether it was economical or necessary to deworm cows. Now most producers are using some type of deworming.
The original deworming debate centered around the question, “Does the deworming of the adult cow increase her productivity enough to justify the cost of deworming?” Now with feed costs at all-time highs, the feed conserved by deworming more than pays for the price of the product.
Now researchers argue, “We must deworm cows before pasture turnout to avoid pasture contamination with parasite eggs and larvae.” The less parasites carried by the cow to grass." The fewer eggs will be shed on the pasture. With the lower population of worm larvae, the fewer larvae calves will consume. These lower worm loads will convert to more calf pounds at weaning. This involves both deworming and pasture management.
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