What is your normal worming routine, and when was the last time he was wormed?
Depending upon where you are, vets may recommend different things. However, the only way to worm appropriately is to do a fecal. Our vet has us doing fecals quarterly instead if the rotational worming, since the parasites are developing resistance, much like the anitbiotic situation in humans. I will say, that I have been pleasantly surprised that neither of mine have needed anything since spring, and we next test in December.
It is pretty simple, and then you KNOW if that is the issue, and exactly how to treat it. No guesswork involved.
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