Animal protein meals provide a good source of essential amino acids (e.g. lysine and methionine), but they are also good sources of energy and minerals read more.

Vegetable protein sources usually come as meal or cake, the by-product of oilseed crops. The main oilseed crops include soybean, rapeseed/canola, read more.

Fish meal is a rich source of high quality protein with a relatively high energy content and are rich in important minerals such as phosphorus, read more.