Preservation of brewers years slurry by a simple on-farm adaptable technology and its effect on performance of weaner pigs

Abstract

Ten batches of brewers yeast slurry (BYS) were analysed for proximate chemical composition, then mixed with ground maize grain (GMG) at 1:2, 1:1.5 and 1:1 w/w ratios; and with cassava root meal (CRM) and cassava peels meal (CPM), both at 1:1 w/w ratio. The mixtures were sun-dried to moisture content of 100 g kg −1 or less, then packed and stored. The mean dry matter (DM) and crude protein (CP) contents of the BYS were 159.5 g kg −1 and 456.0 g kg −1 of DM, respectively. The mixtures of BYS:GMG at 1:2, 1:1.5 and 1:1 w/w contained 122.6 g, 135.6 g and 145.6 g kg −1 CP dry weight, respectively, while the BYS:CRM and BYS:CPM mixtures contained on average 86.5 g and 117.8 g kg −1 CP dry weight, respectively. The BYS:GMG mixtures at 1:1.5 and 1:1 ratios were included in diets to replace respectively 400 g kg −1 (BYS:GMG-1) and 550 g kg −1 (BYS:GMG-II) of protein supplied by 200 g kg −1 of soyabean meal in the control (GMG) diet. Eight crossbred weaner pigs of Large White and Landrace breeds averaging 11.78 kg liveweight, were allocated in groups of four, and in two replicates, to each of the three test diets for a 35 day feeding trial. Mean daily gain was 0.43 kg, 0.42 kg and 0.40 kg, mean daily feed intake was 1.03 kg, 0.95 kg and 0.96 kg, the feed gain ratio was 2.59, 2.35 and 2.39 for GMG; BYS:GMG-I and BYS:GMG-II diets, respectively. These values did not differ significantly ( P > 0.05). Brewers yeast slurry reduced feed cost per kilogram liveweight gain significantly ( P < 0.05) and improved feed utilisation with consequent improvement in pig production efficiency.