Domestic Yak

This is the domestic yak, a farm animal kept by herders, not a wild species; the wild yak is a separate species. The domestic yak is a heavily built, long-haired bovine, built for high altitude with larger lungs and heart than lowland cattle, and thick fat and almost no working sweat glands to cope with the cold. Coats range from white, grey and brown to piebald, with rusty and cream patches common. Both sexes have a shoulder hump and smooth dark horns, and the tail is long and horse-like. Yaks do not low like cattle: they grunt and squeak, which gave the species its name, Bos grunniens (Wikipedia, general species account).

Yaks are kept for milk, wool, meat, dung fuel and as pack and plough animals, and their milk gives butter for tea, lamps and religious butter sculptures and chhurpi cheese. Mating is mainly July to September, calves are born in May and June after about 260 days, and females usually calve every other year. Cattle-yak crosses called dzo are common: males are infertile and females (dzomo) are fertile. The source cites a Bhutanese study on yak herder economics but gives no Bhutan-specific detail (Wikipedia, general species account).