Many animals are raised for their meat. Meat, mainly from farmed animals, is a major source of dietary protein around the world. Cattle generally produce a single offspring annually which takes more than a year to mature; sheep and goats often have twins and these are ready for slaughter in less than a year; pigs give birth to more than one litter of up to about 11 piglets each year. Horses, donkeys, deer, buffalo, llamas, alpacas, guanacos and vicunas are farmed for meat in various regions.