Your question has a couple key features. Chewing on any dead carcass brings up the possibility of unwanted bacterial overgrowth which could create the need for antibiotic therapy, but if he still feels good and is eating it is okay to treat symptomatically at this point. Bland food such as chicken and rice or scrambled egg is a place to start. If the diarrhea persists past tomorrow let me or your vet know. The second concern is if you use any rodent control baits, if you do you let someone know what product and we can advise. Also, using a protectant such as pepto bismol or kaopectate at a dose of about 0.2cc per pound 2-3 times daily for the next day also okay.