Goat's milk is similar to cow's milk, except that the fat globules are smaller and more easily digested. Also, it has no carotene, so it produces a whiter cheese.
Sheep's milk has twice the solids as cow's milk, so the cheese yield is higher. The butterfat content of sheep's milk is 9%.
The balance of all the components of milk is influenced by the breed of the animal, the stages of lactation, the geographical location, environmental conditions and the seasons. All of these factors affect the final outcome of your cheese. For more information about the content of milk, see Chapter 1 in the book, Home Cheese Making.