Long Range is an injectable wormer that can be used on cows or calves, it is a similar compound to dectomax and cydectin. It lasts roughly 80-120 days, depending on the parasite, and is reported to be fairly effective against flies as well, though that isn't a big deal right now. It is fairly pricey and cows generally don't have the internal parasite burden to justify it, it's probably best suited in replacement heifers and stocker cattle.
I would use Cydectin on them. Doesn't matter if you use the pour or injectable formulation, pour is supposed to be slightly better but either would be fine. If you use the injectable, you can pour them with a generic ivermectin (like noromectin) for lice, if that is an issue for you. A single treatment of Cydectin would probably be sufficient, especially in cows, but fighting parasites is a little trickier in Florida than most places so you would do well to contact a local vet.
I would use Cydectin on them. Doesn't matter if you use the pour or injectable formulation, pour is supposed to be slightly better but either would be fine. If you use the injectable, you can pour them with a generic ivermectin (like noromectin) for lice, if that is an issue for you. A single treatment of Cydectin would probably be sufficient, especially in cows, but fighting parasites is a little trickier in Florida than most places so you would do well to contact a local vet.