Studies On The Effects Of Alfalfa Saponin On Fermentation And Other Physiological Functions In Sheep

Two years old Inner Mongolian semi- fine wool wethers of 35kg body weight, with permanent ruminal and proximal duodenum cannulas, were divided into 4 groups of 3 in one factor experimental design and fed a diet with 2:8 concentration: forage ratio to study the effects of 4 adding levels of alfalfa saponin ( 0g/d, 8g/d, 16g/d, 32g/d) on fermentation and other physiological functions in sheep. The study included 9 parts:1 Effect of alfalfa saponin on rumen environment and fermentation of sheep.2 Effect of alfalfa saponin on outflows of nutrients in the rumen and duodenum of sheep.3 Effect of alfalfa saponin on dietary NDF and ADF degradation of sheep.4 Effect of alfalfa saponin on rumen cellulase activity of sheep.5 Effect of alfalfa saponin on rumen microbial flora of sheep.6 Effect of alfalfa-saponin on immune function( subgroups of T lymphocytes in peripheral blood ) of sheep.7 Effect of alfalfa saponin on antioxidative capability of sheep.8 Effect of alfalfa saponin on serum biochemical index of sheep.9 Effect of alfalfa saponin on nitrogen balance and performance of sheep.The results showed as follows :1 When alfalfa saponin was added, the value of pH in the rumen was not altered significantly (p>0.05); but the concentration of NH3-N had a trend of reduction.At day 3 and day 6,NH3-N concentration was decreased significantly (p<0.05);The total VFA in the rumen of the sheep were similar among treamtments (p>0.05),the average concentration of acetate in the rumen digesta was significantly lower (p<0.05),and at the same time,the ratio of acetate to propionate decreased significantly (p<0.05) ;Bacteria protein synthesis in the rumen was higer than control group(p<0.05).2 The liquid flow rates of rumen digest were increased (p>0.05) , nitrogen and microbial nitrogen flows to the duodenum were increased greatly (p<0.05) .3 When treated with alfalfa saponin at level of 8g/d,the apparent degradabity and RED of NDF and ADF were increased (p>0.05).4 There was a trend of increase of activites of cellulases when treated with alfalfa saponin at level of 8g/d at the 6d,the activities of crystal cellulosase and CMCase increased significantly(P<0.05),and there was no significant effect on salicinase and xylanase activity.5 By nylon membrane fleck Blotting using oligoneucleotide probes of 16SrRNA,the relative amount of three predominant ruminal cellulolytic bacteria (Fibrobacter succinogenes,Ruminococcus flavefaciens, and Ruminococcus albus),the population of total fungus total population was determined,the results indicated that total eukaryotes population were increased significantly by the supplementation at levels of 8g/d and 16g/d (p<0.05);At the same time,the relative amount of three predominant ruminal cellulolytic bacteria were enhanced during the experiment periods except 21d; When the level was 8g/d, at day3, the protozoa number was greatly reduced by 20% (p<0.05). In addition, the analysis of protozoa population structure showed that the proportions of Epidinium,Diplodinium and Ophryoscolex were improved,which was benefited to digest dietary fibre .6 Subgroups of T Lymphocytes in Peripheral Blood of Sheep were significantly effected by alfalfa saponin supplementation compared with control at 7 d,14d and 21d. When the adding level of alfalfa saponin were 8g/d and 16g/d,the results of CD4+ T Lymphocytes and CD4+/CD8+ were significantly increased(p<0.05) .7 Antioxidative capability of sheep tended to be increased when added alfalfa saponin. The results showed that the activities of GSH-Px( P>0.05),SOD(P<0.05) and inhibition of H2O2 in serum were higher(P>0.05) and the levels of MDA were found to be lower compared to control (P>0.05).8 The results of blood biochemical indices indicated that adding alfalfa saponin at the level of 8g/d,the glutamic-pyruvic transaminase (GPT),glutamic-oxaloacetic transaminase (GOT) and alkaline phosphatase (ALP) activities were highter respectively (Pï¹¥0.05);The concentration of glucose tended to be higher,but the concentration of total protein was lower at 8g/d (Pï¹¥0.05);While TG concentration had tended to be reduced and HDL-C significantly increased( P<0.05).Compared with the control group, the serum TC,and serum calcium and serum phosphate were not affected.9 When the adding level of alfalfa saponin was 8 g/d, the utilization of nitrogen and daily body gain were improved.In summary,under the condition of this experiments,addition of alfalfa saponin might modulate rumen fermentation including decreasing concentration of NH3-N and increasing microbial protein yield and nitrogen flow to the duodenum;Alfalfa saponin could reduce total protozal count in the rumen, improve total population of bacteria and fungus, and increase the relative amount of three predominant ruminal cellulolytic bacteria. At the same time,antioxdation capability and immune function were enhanced greatly. All these improvments led to significant rise in sheep performance .The present work also demonstrated that the optimum adding level of alfalfa saponin into a sheep diet was 8g/d .