Boer goats commonly have white bodies and distinctive brown heads. Some Boer goats can be completely brown or white or paint, which means large spots of a different color are on their bodies. Like the Nubian goat, they possess long, pendulous ears. They are noted for being docile, fast-growing, and having high fertility rates. The primary market for slaughter goats is a 22–36 kg (49–79 lb) kid; kids should reach marketable size at weaning age. The kid of a proven fast-growing sire might weigh 36 kg (79 lb) at 90 days, while the kid of a poor-quality sire might weigh only 15 kg (33 lb) at 90 days. An average-quality buck will initially be less expensive to purchase, but it can significantly undermine an operation’s long-term profitability.