Wet brewersʹ grains or bean curd pomance as partial replacement of soybean meal for lactating cows

The purpose of this study was to evaluate the effects of supplementation of the by-product, brewersʹ grains and the bean curd pomance, on the performance of lactating cows and their ruminal characteristics. Through this, we wanted to increase resource utilization and to eliminate pollution from these by-products. Thirty-two Holstein lactating cows were allocated randomly into four dietary treatment groups. The experimental diets were formulated to be isoenergetic and isonitrogenous according to National Research Council (1989), and containing 35% corn silage, 20% alfalfa hay and 45% concentrates on DM basis. The dietary treatments consisted of the inclusion of different by-products sources. These included soybean bean (as the control), brewersʹ grains, bean curd pomance, and the mixed by-products (containing the same amount of brewersʹ grains and bean curd pomance). The experimental feeding lasted for eight weeks after one week of adaptation. In addition, four rumen cannulated Holstein cows were used in a 4×4 Latin square with 10-day period for collecting rumen samples. Results showed that cows that were fed the bean curd pomance diet produced significantly more milk than those that were fed the brewersʹ grains diet or the mixed by-product diet. The cows on the control diet produced significantly less milk than the other treatment groups (P<0.05). Both the control and brewersʹ grains groups consumed more feed than those in the bean curd pomance and mixed by-products diet groups (P<0.05). The cows that were fed the mixed by-products diet produced a significantly lower percentage of milk fat, total solids, milk protein and milk lactose than the others (P<0.05). The milk lactose percentage was significantly higher for cows that were fed the bean curd pomance than those fed the brewersʹ grains diet (P<0.05). Cows that were fed the bean curd pomance produced significantly more milk fat, total solids, milk protein and milk lactose than the others (P<0.05). Cows that were fed the mixed by-products diet produced significantly lower amount of milk fat, total solids and milk protein than the control and brewersʹ grains group (P<0.05). These diets did not significantly influence the body weight of the cows. It, however, significantly influenced the ruminal characteristics (P<0.05).