Evaluation of ensiled brewery spent grain as a substitute for protein source concentrate in the diet of Lactating crossbred dairy cows at Adami Tullu Agricultural Research Center

Özet

Feeding different substitution levels of Noug seed cake with ensiled brewery spent grain on milk yield and milk composition of crossbred dairy animals and its net benefit was done at Adami Tulu Agricultural Research Center on Ten early lactating crossbred dairy cows (HF with Arsi) with an average daily milk yield of 5.04 liter and 272.5 kg body weight were selected from nucleus herd at dairy farm. They were randomly assigned to 5 x 2 Latin Square Design composed of five dietary treatments. Each period being split to 15 days of adaptation and 15 days of measurement. The experiment was conducted from January 2024 to June 2024. Concentrate feed Noug seed cake and Wheat bran was purchased from Adama suppliers and brewery spent grain was purchased from nearby local suppliers. Brewery spent grain was allowed to cool under aerated shade for 24 hrs then manually pressed and packed into airtight plastic drum without any preservatives. Rhodes grass hay produced at on station was used as basal diet. The substitution has four levels and compared with previously recommended ration for lactating crossbred cows. The dietary treatments were T1= 66 % wheat bran + 33 NSC + 1% salt (Control), T2= 66 % wheat bran + 24.75 NSC+8.25 BSG + 1% salt, T3= 66 % wheat bran + 16.5 NSC+16.5 BSG + 1% salt, T4= 66 % wheat bran + 8.25 NSC+24.75 BSG + 1% salt and T5= 66 % wheat bran + 33 BSG + 1% salt. Daily feed offered and refused, milk yield and body weight change per 15 days, milk composition at initial and end of each feeding period were collected. The result reveals that the total dry matter intake and body weight gain doesn't differ among the treatments. The milk yield and composition of lactating animals fed feeds with varying amounts of brewery spent grain did not differ significantly. The highest net benefit was obtained from animals fed on dietary treatment 5(100%) replacement of Noug seed cake by ensiled brewery spent grain which was 272.4 ETB/cow/day. Dietary treatment 5 (wheat bran + Brewery spent grain+ salt) was recommended for further evaluation and intervention at on farm level for dairy producers who kept crossbred cows and have access for brewery spent grain especially for urban and peri urban dairy producers.