Offal meal as a protein supplement to cereal-based diets for growing pigs

Abstract

An offal meal (OFM) derived from meatworks wastewater containing hard and soft offals was evaluated in a growth trial and a metabolism study. Cereal-based diets containing either 0, 4, 8, or 12% OFM as supplementary protein were fed to pigs over the live weight range 25-85 kg. Inclusion of OFM in the diet at a level of 4% increased overall daily live weight gain (P<0.05) and improved the efficiency of conversion of meal to body weight but not significantly (P>0.05). Thereafter, with increasing levels of OFM there was a linear decrease in rate and efficiency of body weight gain (P<O.Ol). These responses were confined to the latter period (45-85 kg live weight) of the trial. Dietary treatment did not influence dressing out percentage nor carcass measurements. With increasing levels of OFM in the diet there was a linear decrease (P<0.05) in the apparent digestibility of gross energy; a similar effect was recorded for the apparent digestibility of nitrogen but it was not signifieant (P>0.05). Dietary treatment did not influence N retention.