Since dogs shouldnt eat raw oysters, were providing nutritional information for canned oysters. Oysters are an excellent source of protein, vitamin B12, iron, zinc, copper, manganese, and selenium. They are also a good source of vitamin C, thiamin, riboflavin, magnesium, and phosphorus. On the down side, they are very high in cholesterol. One cup of oysters has just 112 calories. They have a fairly good amount of omega-3 fatty acids at more than a 10:1 ratio to omega-6 fatty acids ...