Study On Application Effect Of Animal Protein Diet Of Different Sources In Early Weaned Piglets

The experiments were conducted to evaluate the effects of SDPP,SDBC and DPS on the production performance, intestinal mucosa morphology, immune function and apparent digestibility of nutrients in early weaned piglets.Experiment one: Seventy-two 21-day-old PIC weaned piglets were randomly divided into control group, SDPP group, SDBC group and DPS group, to carry out 4-week feeding trial. The results showed that: In four weeks, Average daily gain (ADG) was increased by 11.69% and 7.54% compared with control group (P>0.05) in DPS group and SDBC group, but was decreased by 21.09% in SDPP group (P>0.05). Feed/Gain (F/G) was decreased by 11.60% and 11.05% in DPS group and SDBC group, but was increased by 13.81% in SDPP group (P>0.05). The results indicated that the feeding effects of DPS group and SDBC group better than control group and SDPP group in this experiment.Experiment two: After the feeding test, slaughter a piglet from each repeat for research small intestinal mucosa morphology. The results showed that: In SDPP group, Villous height(VH) and Mucosal thickness(MT) of duodenal were verey significantly increased(P<0.01), VH/CD of duodenum and terminal jejunum were significantly increased and Crypt depth (CD) of mid-jejunum was significantly reduced (P<0.05). In SDBC group, VH of duodenum, VH/CD of proximal jejunum and VH, MT, VH/CD of terminal jejunum were verey significantly increased(P<0.01); VH/CD of duodenum, mid-jejunum, ileum and MT of duodenum were significantly increased (P<0.05); CD of mid-jejunum and ileum were significantly reduced(P<0.05). In DPS group, VH, MT of duodenum and VH/CD of terminal jejunum were verey significantly increased(P<0.01); VH/CD of proximal jejunum and VH, MT of ileum were significantly increased (P<0.05).Experiment Three: The experiment studied on T cell positive rate by ANAE staining and B cell positive rate by RNA staining of periphery blood and small intestinal mucosa. The results showed that: In SDPP group, T cell positive rate of periphery blood at the 19th day of post-weaning and B cell positive rate of periphery blood in entire post-weaning period were significantly increased(P<0.05), and T, B lymphocytes positive rate of jejunal mucosa lamina was significantly increased(P<0.05). In SDBC group, T lymphocytes positive rate of periphery blood was significantly increased at the 28th day (P<0.05) and B lymphocytes positive rate of periphery blood was very significantly increased at the 19th day (P<0.01) after weaning;T lymphocytes positive rate of duodenal mucosa and the jejunal mucosa were increased very significantly(P<0.01), T lymphocytes positive rate of Ileal mucosa was significantly increased(P<0.05), B lymphocytes positive rate of all segments of the small intestinal mucosa had no significant difference, but higher than the control group(P>0.05). In DPS group, the T,B cell positive rate of periphery blood was increased in all phases of post-weaning, but the difference was not significant(P>0.05), T lymphocytes positive rate of the duodenal and B lymphocytes positive rate of jejunal and ileal mucosa were significantly increased(P<0.05). These indicated that the three protein sources can enhance immunity of piglet.Experiment Four: The experiment studied the effect of SDPP,SDBC and DPS on nutrient apparent digestibility in weaned piglets. The results showed that: In SDPP group, digestibility of crude protein, crude ash, Ca and P were increased by 4.79%(P<0.05), 54.62%(P<0.01), 35.76%(P<0.01), 31.34%(P<0.01) compared with control group. In SDBC group, there was no significant difference (P>0.05) in digestibility of crude protein, but digestibility of Crude ash, Ca and P were increased by 19.09%, 33.73%, 28.44%(P<0.01). In DPS group, the digestibility of crude protein, Crude ash, Ca and P were very significantly increased by 10.14%, 67.43%, 55.63%, 44.91%(P<0.01).