Effect Of Oligopeptide On Digestive Physiology And Protein Synthesization Regulation For Broilers

Oligopeptide nutrition theory is a important and newly part of protein nutrition . More and more evidence proved that the absorption and metabolism of oligopeptide was significantly different with that of free amino acid. The study about oligopeptide was mainly focus on oligopeptide transporter cloning and expression and founction of active oligopeptide in body. The basic knowledge about oligopeptide (such as process of digestion and metabolic, absorption and utilization, physiological and biochemical reaction) was absent and unsystematic.In the paper, the metabolism and comparison with free amino acid of oligopeptide was discussed through metabolic, biochemical, dynamic and molecular method to promote protein theory development.Experiment 1: Effect of oligopeptide on energy and protein deposition and relative metabolic index To measured the different protein resource ME and energy and protein deposition in broilers, two trails was carried on.Exp 1: 18 1.8-2.5kg AA broilers was divided into 3 groups randomly and forced fed 50g/bady diet with FAA, oligopeptide and casein as protein resource respectively. The AME of the three kind of diet was 14.94 MJ/Kg,15.13 MJ/Kg and 15.25 MJ/Kg(P<0.05);Ex'p 2: 180 14-day old AA broiler was selected and divided into 3 groups randomly and fed with three kind of purified diet which FAA, oligopeptide and casein as protein resource. The 28-day old body showed that energy deposition in feather, carcass and,total body was 0.083MJ/Kg,0.075MJ/Kg and 0.095MJ/Kg (P>0.05) ;0.55MJ/Kg, 0.71MJ/Kg and 0.94MJ/Kg, (P<0.05); 0.65MJ/Kg,0.78MJ/Kgand 1.03MJ/Kg(P<0.05)respectively. The protein deposition in feather, carcass and total body was 2.15g, 2.87g and 4.08g (P<0.05) ,15.01g,18.25g and 20.08g, (P<0.05), 17.75g, 21.12g and 24.16g (P<0.05) respectively; The ALT level in blood serum of oligopeptide and casein groups was significantly higher than FAA group's while the UA was lower (P<0.05) .Experiment 2: Effect of different level oligopeptide on growth performance and related hormone secretion To study the effect of different level oligopeptide on growth performance and related hormone secretion of broiler, 360 1-day old AA broilers were selected and divided into 6groups and fed with six kinds of different level oligopeptide diet. The trail last 3 weeks. The results indicated that ADG , VFI and FCR of FAA and oligopeptide mixtures increased by 0.17% 18.70%, 0.89% 11.83% and 3.18%-13.66% respectively. The hormone (such as T₃ T₄.. GH IGF-I)level in blood serum was changed regularly with oligopeptide level.Experiment 3:Effect of peptide on small intestine development and related enzyme secretion To discuss the effect of peptide on small intestine development and related enzyme secretion. 450 1-day old AA broilers was selected and divided into 6 groups and fed with six kinds of diet. The length and weight of duodenum, jejunum and ileum at 7, 14. 21 days was measured and the relevant index was calculated respectively. The villus height and recess depth was measured and villus height/recess depth was calculated. The activity of pepsin, trypsin and chymotrypsin was also tested. The results showed :(1).