Effects Of In Ovo Feeding Of N-Carbamylglutamate On Meat Quality Of Broilers

The current study was performed to determine the influence of in ovo feeding of Ncarbamylglutamate(NCG)on hatchability,growth performance,slaughter performance and meat quality in broiler chicken.The mechanism of in ovo feeding of NCG on broiler meat quality was preliminarily explored from the aspects of muscle fiber type,energy metabolism and antioxidant capacity.Experiment 1.The effect of in ovo feeding of NCG at different time of incubation on hatchability,growth performance,slaughter performance and meat quality in broilers.A total of 1680 commercial fertilized eggs of rose 308 broilers were assigned to seven treatments randomly: Control group,3 Saline group and 3 NCG group.There were 6 replicates in each treatment.The saline and NCG injection treatments were an injection with 0.1 mL 0.85% aseptic saline alone or containing 2 mg NCG per egg at 7,12 and 17.5 d of incubation.Upon hatching,72 healthy male chicks of each treatment were randomly assigned to six cages for a 42-day feeding test.At the age of 42 days,muscle samples were collected to determine meat quality.Results: In ovo feeding of NCG at 12 or 17.5 day of incubation could increase the hatchability and shorten the hatching window.The growth performance and slaughter performance were not significantly improved by in ovo feeding of NCG at different time of incubation.Amniotic injection of NCG at 17.5 day of incubation could significantly decrease drip loss,pressure loss,shear force and improved the meat quality of pectoral muscle in broilers.Experiment 2.The effect of in ovo feeding of NCG on the flavor and nutritional composition in pectoral muscle of broilers.A total of 600 commercial fertilized eggs of rose 308 broilers were assigned to two treatments randomly(with 6 replicates): Control group and NCG group.The NCG injection treatment was an injection with 0.1 mL 0.85% aseptic saline containing 2 mg NCG per egg at 17.5 d of incubation.Upon hatching,72 healthy male chicks of each treatment were randomly assigned to six cages for a 42-day feeding test.Results: In ovo feeding of NCG significantly increased the content of crude protein,proteolytic Arg,free Arg and Ala in pectoral muscle of 42 d broilers.In ovo feeding of NCG changed the response value of volatile flavor substance to electronic tongue sensor,reduce the value of bitter and astringency,and improved the richness,in pectoral muscle.Experiment 3.The effect of in ovo feeding of NCG on glycolysis potential,antioxidant capacity,muscle fiber type in pectoral muscle of broiler.The process of hatching and feeding were same as test 2.Results: Compared with the control group,in ovo feeding of NCG resulted in a lower content of lactate and malonadialdehyde(MDA),and increased the activities of catalase(CAT)and glutathione peroxidase(GSH-Px).Pectoral muscle from in ovo feeding of NCG group showed higher percentage of type I fibers,and cross-sectional area of fibers.Moreover,the gene expression of Myhcsm,Mystatin,PPAR-? and PGC-1 ? in pectoral of broilers were significantly upregulated by injecting of NCG.The results showed that in ovo feeding of NCG increased the proportion of type I muscle fibers by up-regulating the gene expression of PGC-1 ?,PPAR-? and MSTN,increased the antioxidant capacity,delayed the glycolysis process and reduced the content of lactic acid,in pectoral muscle.In conclusion,the optimal time of in ovo feeding was 17.5 d of incubation.Amniotic injection of 2 mg NCG in 17.5 d of incubation could improve the water holding capacity and tenderness,increase the content of protein and Arg,in pectoral muscle.Meanwhile,the smell and taste of pectoral muscle were improved with injecting of NCG.In ovo feeding of NCG increased the proportion of type I muscle fiber by up-regulating the expression of myostatin,PPAR-? and PGC-1 ?,increased the capacity of antioxidant,thereby improving the meat quality of broilers.