Effect Of Canola Meal On Rumen Fermentation And Milk Performance In Dairy Cows

This experiment was conducted to study the effects of canola meal instead of soybean meal and cotton meal on rumen fermentation and production performance and immune function of dairy cows, to assess an application value of canola meal in feeds of cows and possibility of reducing production cost and to provide theoretical basis for addition of in diet of canola meal dairy cows.The experiment was divided into 4 parts. Trail 1: Three healthy Holstein cows fitted with ruminal cannulas were selected,based on nylon bag technique,to research the effect of canola meal on dynamic degradation in rumen. Trail 2: Three Holstein cows fitted with ruminal cannulas were chose to study the effects of canola meal on the rumen fermentation of dairy cows, with a diet condition of high protein ration(10.5%) and low protein ration(8.5%). Trail 3 and Trail 4 were conducted to research the effects of canola meal on milk production and immune functions of dairy cows fed high protein ration(14.5%) and low protein ration(12.5%).The results showed that:1.The effective degradation rate of protein and dry matter of canola meal in rumen were 59.06% and 55.17% respectively.2.The effect of canola meal on pH value, BCP and VFA contents of rumen in dairy cows fed high protein ration(10.5%)and low protein ration(8.5%)were not significant(P>0.05), but NH3-N concentrations in rumen were significantly decreased (P<0.05).3.The diet containing 14.5% crude protein with 5% canola meal instead of soybean meal and cottonseeds meal had no significant influences on milk composition and somatic number and IgG and IgM concentrations in serum (P>0.05). However, fat yield and protein yield were increased (P<0.05) and milk yield was increased 0.76 kg per head per day compared with control group.4.The diet containing 12.5% crude protein with 2.5% canola meal instead of soybean meal and cottonseeds meal had no significant influences on milk production ,milk composition , average fat yield and milk protein yield ,somatic number and concentrations of IgG and IgM in serum (P>0.05).5.Using the canola meal instead of soybean meal and cotton-seed meal in diet dairy cows could increase economic benefits.