Measure The NE Of Rapeseed Meal And Cottonseed Meal And Its Effect On The Growth Performance And N Utilization Of Growing-pigs

Abstract:The net energy of rapeseed meal and cottonseed meal were calculated on basis of actually evaluating the apparent digestible energy (ADE) and apparent metabolizable energy(AME),then combining the NE of corn and soybean meal which have predicted by our laboratory. Four different diets with the corn,soybean meal,rapeseed meal and cottonseed meal based on the same NE level were formulated to investigate the influence of different ingredient matching on growth performance and N utilization of growing-pigs.A 3×3 Latin-square design was used,6 DLY castrated male pigs weighing(30±0.72)kg were used to measure the DE,ME of rapeseed meal and cottonseed meal using the substitution method, and then analyzed the CP,EE,ST and ADF of the two ingredients.Take the ADE,AME and chemical composition of ingredient into the NE regression equation, then the NE value of ingredient can be predicted. In the growth trial, 32 DLY growing pigs, with an average weight of (20.36±0.39)kg were randomly assigned to 4 treatments, which were corn soybean meal (CS)group and 3%,5%,7% rapeseed meal and cottonseed meal(RC) group, respectively, with 8 replicates per treatment and 1 pig per replicate. Each dietary had the same NE(9.84MJ/kg) and true digestible Lys (0.79%)level according by Chen liu (2009). The feeding trial lasted for 42d. Four pigs per treatment were chosen to measure the N utilization by 6d N balance trial with the pigs weighing average 30kg. The results indicated that:The ADE, AME and NE of rapeseed meal was respectively 3065kcal/kg,2706kcal/kg and 1566kcal/kg(all basis on DM); the ADE, AME and NE of conttonseed meal was respectively 2941kcal/kg,2574kcal/kg and 1432 kcal/kg (all basis on DM).There were no significant difference in ADG and ADFI between CS group and 3%RC group,5%RC group (P>0.05). But when the proportion of the rapeseed meal and cottonseed meal respective increase to 7%, the ADG of pigs were significantly decreased(P<0.05) than that of the pigs fed the CS group and 3%RC group;The ADFI of pigs were no significant difference between each group except that of 7%RC group was significantly lowered (P<0.05) than 3% or 5% RC group;The F/G of RC groups were no significant difference (P>0.05) compared with that of CS group except 5%RC group, the F/G of 7%RC group had improved tendency compared with 3% or 5% RC group (P> 0.05). As rapeseed meal and cottonseed meal increasing,the N digestibility,N retention rate and N-ABV were respectively decreasing.Compared the N intake,N retention rate and N-ABV, there were no significant difference (P>0.05) between RC groups and the Corn-Soybean meal, but the N digestibility of 7% RC group was significantly decreased than that of other groups (P<0.05)The regression equations of Noblet et al., (1994):NE1=0.700×DE+1.61×EE+0.48×ST-0.91×CP-0.87×ADF; NE2=0.726×ME+1.33×EE+0.39×ST-0.62×CP-0.793×ADF, could accurately predict the NE based on the measured DE and ME of ingredients; when the dietary DM and true digestible Lys was 86% and 0.79%,respective, the 9.84MJ/kg dietary NE level can meet the energy requirement of 20-50kg growing pigs.