The evaluation of fresh sweet liquid whey as a protein supplement to maize for growing pigs

Abstract

Whey protein, provided by liquid cheddar cheese whey, or a dried protein concentrate was evaluated as a protein supplement to maize-based diets for growing—finishing pigs. In Trials 1 and 2, pigs received either water or fresh liquid whey with a maize-based dry diet, to provide three levels of total dietary crude protein (CP). Liquid whey maintained growth rates at the level of pigs receiving the highest CP level and water, despite a reduction in CP intake of 33%. Liquid consumption by pigs given fresh cheddar whey was 2–3 times that of pigs given water. Whey solids supplied 24.0–58.5% of the total dry matter (DM) consumed by growing—finishing pigs. In Trial 2, pigs given maize supplemented only with vitamins, minerals and fresh cheddar cheese whey ad libitum grew as well as pigs fed on a maize and soya bean meal diet containing 18.1% CP. In Trial 3, dried whey was compared to soya bean meal as a supplement to maize protein, when both provided 50% of the total protein. The daily gain with whey protein as the supplement was 1.36 times that when soya protein was used. Whey protein is shown to be superior to soya as a supplement to maize. Although the dry matter (6%) and protein (0.8%) of liquid whey is low, a high voluntary consumption by pigs make it a good protein supplement in maize-based diets.