Create winter health plan to limit disease
Remember worms and fluke are pasture parasites and are continuously active while the animals are grazing. Your choice of wormer should consider the following: short-acting versus long-acting.
Short duration anthelmentic and flukenides are usually cheaper and in the form of oral doses. They work immediately, but if further parasite intake occurs or more eggs hatch later, then a repeat dose is required.
Medication with residual activity such as avermectins are available in injectable and pour-on formats, making them very convenient to use.
They are usually more expensive but do not require repeat dosages in the case of internal gut and lungworms. Important to note that combination fluke and worm treatments may be long-acting for worms but not so for fluke. Fluke treatment is more effective if given several weeks after the animals are housed, ie if dosed at housing, then repeat the dose four to six weeks later.
Lice on cattle are in two broad categories: biting lice and sucking lice. Lice are parasites that thrive more in winter than summer. They are noted as yellow eggs at the base of the hair when parted. The close contact during housing and the thicker coat in winter all work to increase the volume and the spread of lice. One important point is that a product may claim to control lice as in biting lice, but may not control sucking lice.
Consult your veterinary practitioner as to what's the best product for your farm and ensure to include this in your winter health plan.