Common Sheep: Feed it if it's hungry, tries to group with others.
Fat Sheep (yellow): Keep it away from food before it's too fat to move. Slow. Always wanting to eat.
Black Sheep: It can make the whole group become nervous, keep it away until it's calmed enough.
Male Sheep (red): The group follows it, it doesn't get nervous by a black sheep but it can get angry if dog is making too much pressure on it, then it attacks.