TREAT it!! It will make a huge difference in the condition of your cattle. Warbex, Ivomec, are both great we used Ivomectin?? it's a generic that treats both internal and external parasites. The cows are looking great everytime you move them treat them it works wonders.
The problem with grubs is that they tunnel through the hide of the animal. Now depending on where they are in the hide when you kill them can affect the actual health of the animal. Bot Ivormectin and warblex kills grubs. If you read the bottles they will tell you when (time of year )you should not use the products. Normally this is in the fall/winter months (around Nov through about Feb I think...be sure to read the bottle). Warblex is more for killing lice and grubs (which you should kill) Ivermectin kills lice grubs AND deworms the animal as well. I use Ivermectin from about April through September.
As the grubs migrate through the body, they will accumulate arouond the esophogous, etc. If you kill them while they are in those areas the animal can be strangled from the dead grubs. You either do it early in the life cycle while they are still in the outher connective tissues, or later after they've migrated closer to the back. You want to kill them, just not this time of year
I guess I'm lost, Dun. You're saying NOT to kill any grubs that infect your cattle?
Or, just don't use Warbex for lice because it will kill grubs (which might kill the animal)?