Effect Of Corn Germ Meal And Rice Bran On The Production Performance Of Lactating Cows

This experiment used rumen nylon bag technique combined with feeding experiments to determine the degradation characteristics of corn germ meal and rice bran in Holstein cow and evaluated the effects of adding corn germ meal and rice bran in the diet on performance,ruminal fermentation and serum biochemical indexes.The experimental methods and results are as followed:The first experiment examined the rumen degradability and effective degradability of corn,germ meal and rice bran in four Holstein cows using nylon bag technique.The results showed that the effective degradability of DM,CP,NDF and ADF in corn germ meal were 30.47%,31.87%,27.64%and 20.70%,respectively;the effective degradability of DM,CP,NDF and ADF in rice bran were 53.85%?55.61%?53.45%and 52.86%,respectively.The second experiment evaluated the effects of adding corn germ meal and rice bran in the diet on the production performance.24 Holstein cows were chosen,which have the similar parity,milk yield and lactation days and divided into 4 groups randomly.According to NRC,the diet in control group have no germ meal and rice bran while the experimental groups contained 6.80%of corn germ meal and 3.40%rice bran(group A),13.30%of corn germ meal and 6.65%rice bran(group B),19.98%of corn germ meal and 9.98%rice bran(group C).All cows were fed three times per day at 7:30,14:30 and 20:30.The total experiment period were 56 days,among which had 14 days prefeeding period and 42 days experimental period.The results showed that the diet containing 6.80%of corn germ meal and 3.40%rice bran and the diet containing 13.30%of corn germ meal and 6.65%rice bran can significantly increase DMI of diary cows(P<0.01)and improve 4%standard milk yield significantly s(P<0.1).In the meantime,there was no significant effect on feed efficiency,milk fat percentage,milk lactose percentage,milk total solids and milk urea nitrogen when adding corn germ meal and rice bran(P>0.1).Adding 6.80%corn germ meal and 3.40%rice bran in the diet can produce the best economic benefits with profile of 12.61 yuan per day.The third experiment examined the effect of adding corn germ meal and rice bran in the diet on rumen fermentation and microflora.The experimental designs was the same with the second experiment,and rumen fluid was collected at 2 h after morning feeding.The results showed that the diet containing corn germ meal and rice bran had no significant effect on ruminal pH,NH3-N,MCP and VFA(P>0.05)while the group of adding 6.80%of corn germ meal and 3.40%rice bran can improve the relative levels of Ruminococcus flavefaciens and Butyrivibrio fibrisolvens(P<0.1).The fourth experiment analyzed the effects of adding corn germ meal and rice bran in the diet on the serum biochemical indexes of diary cows.Same designs with the second experiment was used and blood samples were obtained from tail vein at 2 h after morning feeding The results showed that adding 6.80%of corn germ meal together with 3.40%rice bran in the diet can decrease the level of ALP,NEFA and BHBA in the serum(P<0.05)and increase the level of CHO and HDL(P<0.05)while other biochemical indexes were not different from the control group(P>0.05).Conclusion:Adding 6.80%of corn germ meal together with 3.40%rice bran in the diet of mid-term lactation cows can lower the cost of feedstuff,improve the milk production and increase economic benefits effectively.