The Effects Of Fattening Patterns On Enzyme Activities And Gastrointestinal Tract Morphology Of Hulun Buir Lambs And F1Hybrid Lambs Between Hulun Buir And Dorper Sheep

This article primarily reviewed the effects of fattening patterns on enzyme activities in small intestine and morphology of gastrointestinal tract of Hulun Buir lambs and Fl Hybrid lambs between Hulun Buir and Dorper Sheep. The results provided a scientific basis for the optimized fattening program in Hulun Buir lambs and F1Hybrid lambs between Hulun Buir and Dorper sheep. In the experiment,1204-month-old and healthy lambs similar in age, body weight and body condition were chosen, and were divided into4groups,30replicates for each group respectively, to examine the effects of fattening patterns on enzyme activities in small intestine and morphology of gastrointestinal tract of lambs. Half of them were Hulun Buir lambs and half were Fl Hybrid lambs between Hulun Buir and Dorper sheep. The experiment was a2×2factorial arrangement design, and the first factor was fattening patterns, including grazing feeding and grazing with supplementation, and the lambs for grazing feeding were grazed in natural pasture in accordance with the original way, and the lambs for grazing with supplementation were supplemented with concentrates after natural grazing feeding. The second factor was breed, divided into Hulun Buir lambs and FI Hybrid lambs between Hulun Buir and Dorper sheep. The experimental lasted60days, including prophase and anaphase. Each lamb was fed with0.27kg concentrates and0.53kg concentrates respectively in the prophase and anaphase of fattening everyday. At the end of the test, five lambs respectively from each group were slaughtered after fasting for24h and depriving water for2h, and the intestine and pancreas samples were collected.The experiment is divided into three parts:part one studied on effects of fattening model on activities of enzyme in small intestine and pancreas of Hulun Buir lambs and F1Hybrid lambs between Hulun Buir and Dorper sheep. Part two researched the morphology changes of gastrointestinal tract of the lambs under two kinds of fattening patterns. Part three elucidated the effects of fattening model on morphology in small intestine of lambs.Under the present experiment conditions, the study indicated that:(1) Compared with natural grazing feeding, grazing with supplementation could significantly increase trypsin activities, lipase activities and chymotrypsin activities of duodenum (P<0.01, P=0.02, P<0.01); amylase activities (P=0.03, P<0.01, P <0.00), lipase activities (P<0.01,P<0.01, P<0.01), trypsin activities (P<0.01, P <0.01, P=0.01) of jejunum, ileum and pancreas.(2) Copmared with Hulun Buir lambs, amylase activities and chymotrypsin activities (P=0.03,P=0.01) of duodenum, trypsin activities(P=0.01, P<0.01) and lipase activities (P=0.04, P=0.02) of jejunum and ileum of F1Hybrid lambs between Hulun Buir and Dorper sheep were significantly increased. Trypsin activities of duodenum and lipase activities of pancreas (P=0.07, P=0.07) of F1Hybrid lambs between Hulun Buir and Dorper sheep tended to be increased copmared with Hulun Buir lambs.(3) Compared with natural grazing, grazing with supplementation could significantly increase thickness of gastric wall in rumen, reticulum, omasum and abomasum(P<0.01, P=0.01, P<0.01, P<0.01), thickness of muscle layer of gastric wall in rumen, reticulum, omasum and abomasum (P=0.01, P<0.01, P=0.04, P<0.0001), papillae length and papillae width of rumen(P=0.01, P<0.01).(4) The thickness of gastric wall in omasum was significantly increased for F1Hybrid lambs between Hulun Buir and Dorper sheep copmared with Hulun Buir Iambs. The thickness of muscle layer of gastric wall in rumen and abomasum (P=0.06, P=0.10) of F1Hybrid lambs between Hulun Buir and Dorper sheep tended to be increased copmared with Hulun Buir lambs.(5) Compared with natural grazing, grazing with supplementation could significantly increase width of intestinal villus(P<0.01, P<0.01, P<0.01), length of intestinal villi(P <0.01, P=0.04, P<0.01), ratio of intestinal V/C(P<0.01, P<0.01, P<0.01); significantly decrease depth of intestinal crypt in duodenum, jejunum and ileum (P<0.01, P=0.01, P=0.03).(6) Length of intestinal villi in duodenum(P=0.02), width of intestinal villus in jejunum and ileum (P=0.02, P<0.01) were significantly increased for F1Hybrid lambs between Hulun Buir and Dorper sheep copmared with Hulun Buir lambs. The width of intestinal villus and ratio of intestinal V/C in duodenum (P=0.09, P=0.10), length of intestinal villi in jejunum(P=0.08) and ratio of intestinal V/C in ileum (P=0.06) of F1Hybrid Iambs between Hulun Buir and Dorper sheep tended to be increased copmared with Hulun Buir lambs. The depth of intestinal crypt in jejunum and ileum (P=0.08, P=0.07) of F1Hybrid lambs between Hulun Buir and Dorper sheep tended to be decreased copmared with Hulun Buir lambs. (7) Grazing with supplementation could improved the digestve functions of gastrointestinal tract of Hulun Buir lambs and F1Hybrid lambs between Hulun Buir and Dorper sheep, and enhanced morphology development of gastrointestinal tract. The digestive functions of gastrointestinal tract of F1Hybrid lambs between Hulun Buir and Dorper sheep had better effect than Hulun Buir lambs.