In 2001, the livestock population was estimated at 47 million sheep, 38.3 million head of cattle, 40 million goats, 3.2 million camels, and 37.5 million chickens. The national livestock herd was second only to that of Ethiopia in Africa. Cattle, found mostly in the southern rainfall area, are of two types: the shorthorn zebu of Asian origin and the longhorn sanga. Nomadic or seminomadic pastoral tribes own the bulk of the cattle. Sudanese sheep have hairy coats and are grown for meat rather than wool. They are owned almost exclusively by nomadic or seminomadic tribes. The tsetse fly prevents livestock raising in an area of approximately 200,000 sq km (77,000 sq mi) in the south. Livestock products in 2001 included an estimated 3,168,000 tons of cow's milk, 693,000 tons of meat, and 46,000 tons of eggs. Widespread smuggling also reduces income available to the government from livestock exports.