An Alpaca will eat 1 – 2% of its body weight in one day. 80% of this total amount needs to be forage; i.e hay or grass of between 10-15% protein. This averages out to around two pounds of forage per day. The remaining 20% should be a mineral and feed supplement high in nutrients to replace in the body what the forage is not supplying or what a cria is potentially taking through the milk. Always have your pasture and hay analysed for content. Stressful conditions i.e.: extreme cold/heat, weaning, moving or late lactation and gestation call for an increase and adaptation of these amounts.
There are mineral mixes and feeds designed specifically for alpacas and llamas in either loose or pellet form, Mineral blocks are not recommended as Alpacas can not lick them as readily as they can eat a lose mix. Mineral and feed supplements are required year-round for producing Hembras (females) and growing herd members. They will also browse shrubs and trees if available. Supplemental hay may be advisable in summer in poorer quality pastures.
A good rule of thumb – early cut hay (if its alfalfa the flower is still in the boot) of thin stock with no rain 1 – 1000 lb round bale per alpaca per year should suffice, plus 1 cup/alpaca /day of mineral pellets in the winter. This is only in perfect conditions to give an idea.