Effect of Different Levels of Soybean Oil, Soybean and Canola Meal on Production Performance, Rumination Activity and Nutrient Digestibility in Holstein Dairy Cows

The purpose of this study was to evaluate the effect of different levels of oil and soybean meal and Canola meal separately and mixed on productive performance, rumination and digestibility of nutrients in Holstein dairy cows. This research was carried out in a completely randomized design on 35 Holstein dairy cattle with 7 treatments and 5 cows with an average weight of 650 ± 40 kg. Treatments were: 1- control group (basal diet), 2- basal diet+ 4% soybean oil, 3- basal diet+ 10% soybean meal, 4- basal diet+ 4% Canola oil, 5- basal diet+ 10% Canola meal, 6- basal diet+ 4% soybean oil + 10% soybean meal, 7- basal diet+ 4% Canola oil + 10% Canola meal. The results of this study showed that with the use of soybean meal and soybean oil, the amount of milk produced per day increased milk production by 3.5% fat and milk production by 4% fat and the difference was significant (P <0.05) with other groups. There was a significant difference between the average duration of chewing, rumination and eating among different diets (P <0.05). The results showed that there were significant differences in the apparent digestibility coefficients of dry matter, fat and organic nutrients between different diets (P <0.05). The use of soybean oil and soybean meal improved yield of milk production.