Here's a good article on why:
GOT GOAT'S MILK?
What does goat's milk give you that cow's milk doesn't? In many parts of the world, goat's milk is preferred to cow's milk. Even in the United States, the goat is gaining popularity. Goats eat less and occupy less grazing space than cows, and in some families the backyard goat supplies milk for family needs. Goat's milk is believed to be more easily digestible and less allergenic than cow's milk. Does it deserve this reputation? Let's disassemble goat's milk, nutrient-by-nutrient, to see how it compares with cow's milk.
Different fat. Goat's milk contains around ten grams of fat per eight ounces compared to 8 to 9 grams in whole cow's milk, and it's much easier to find lowfat and non-fat varieties of cow's milk than it is to purchase lowfat goat's milk. Unlike cow's milk, goat's milk does not contain agglutinin. As a result, the fat globules in goat's milk do not cluster together, making them easier to digest. Like cow's milk, goat's milk is low in essential fatty acids, because goats also have EFA-destroying bacteria in their ruminant stomachs. Yet, goat milk is reported to contain more of the essential fatty acids linoleic and arachnodonic acids, in addition to a higher proportion of short-chain and medium-chain fatty acids. These are easier for intestinal enzymes to digest.
Different protein. Goat milk protein forms a softer curd (the term given to the protein clumps that are formed by the action of your stomach acid on the protein), which makes the protein more easily and rapidly digestible. Theoretically, this more rapid transit through the stomach could be an advantage to infants and children who regurgitate cow's milk easily. Goat's milk may also have advantages when it comes to allergies. Goat's milk contains only trace amounts of an allergenic casein protein, alpha-S1, found in cow's milk. Goat's milk casein is more similar to human milk, yet cow's milk and goat's milk contain similar levels of the other allergenic protein, beta lactoglobulin. Scientific studies have not found a decreased incidence of allergy with goat's milk, but here is another situation where mothers' observations and scientific studies are at odds with one another. Some mothers are certain that their child tolerates goat's milk better than cow's milk, and mothers are more sensitive to children's reactions than scientific studies.
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