Vol. 9, Special Issue 4, Part D (2025)

The study was conducted to investigate the effect of low crude protein diets supplemented with synthetic amino acids on performance of growing cross-bred (Yorkshire × Zovawk) pigs. Twenty cross-bred pigs of similar age (2-3 months) and average body weight (12.42±0.68 kg) were randomly allocated into 4 groups (G1, G2, G3, G4) with 5 animals in each group. Standard grower ration having 20.9 % crude protein (CP) was prepared as per National Research Council (NRC), 1998 and fed to G1(control) group. All the animals were fed isocaloric diet with different protein level with or without amino acid supplementation. The rest three groups were fed 18% CP i.e. G2 group was fed grower ration with 17.9% CP i.e 3%unit reduction of standard CP level without synthetic amino acids. Experimental animals of G3 were fed diet containing 17.9% CP and supplementation of synthetic amino acid Lysine and G4 group animals were fed diet with reduced protein (17.9%) and supplemented with Lysine, methionine and threonine to fulfil the requirement (NRC, 1998). During the whole feeding trial of 30 days there was no significant difference (p>0.05) in average dry matter intake, average daily gain and feed conversion ratio among the different treatment groups. Blood biochemical parameters analysis revealed that serum glucose, total protein, albumin, globulin, urea, creatinine, triglycerides, cholesterol and SGOT value were within normal range and no significant difference (p>0.05) were observed among the treatment groups. It was concluded that the reduction of dietary protein by 3% unit of NRC (1998) feeding standard in the diet of weanling cross-bred (Yorkshire x Zovawk) did not have any adverse effect on the growth performance and blood biochemical profile of the pigs.