I feed TOTW's Bison & Venison also, no issues.

At 6 months I think you can switch to adult kibble
and feed 1 & 1/2 cups twice daily. Check this tho,
haven't had a puppy in a long time.

If he's not vomiting, do as Lynn (and Vet) suggests,
boiled chicken & white rice for a week. If he starts
vomiting and the runs persists, take him in.