Venison & MulberryGrain Free Venison With Sweet Potato & Mulberry for Dogs Venison: This protein source is rich in iron as well as B vitamins including B6 and B12. Iron Essential for the proper functioning of red blood cells, low iron levels can lead to anemia. Anemic dogs are more prone to injury, illness, and they are more lethargic and listless. Niacin Vitamin B3 is known to help circulation and reduce levels of inflammation. Riboflavin Vitamin B2 combines with