Fiendish Buffalo
Fiendish buffalo is delightful: it usually comes with a delightful pre-smoked flavour. Some varieties may be spicy...as in "Deviled".
Mechanically per the SRD there are no other effects, nor would I recommend any in this adventure: the PC's are probably pretty low on supplies anyway.
That said, I ran a two-part adventure once in a lower magic world that made different assumptions. The PC's were hired to hunt a giant vicious boar that had been attacking caravans. It turned out to be an advanced fiendish boar (which was a story in itself). After they killed it, they butchered it and sold the meat to the people of the village. It was a big boar. It was a lot of ham and pork.
Two weeks later, they discovered that if someone ate enough fiendish pork, they turned into a wereboar.
Something like three-quarters of the villagers transformed into wereboars, made the alignment shift, ceased farming, and took to banditry. Now that entire part of the country is being raided by wereboar bandits, requiring the king to send a small army to restore order.
The PC's have two iron-clad rules now.
1. "Don't eat pork."
2. "Never trust a butcher."
If I ever run them through my Sweeney Todd adventure, I think I can create a party of vegan adventurers.