Compairing the effect of supplementing a mixed buffer and sodium bicarbonate on ‎growth performance and rumen parameters of Holstein young bulls ‎

This study aimed to compare the effects of combined buffer and sodium bicarbonate on growth performance and ruminal parameters of Holstein young bulls with an average weight of 330.8±43.1 kg and an age of 240 days, fed with a high-concentrate diet. The experiment was conducted for 90 days with 10 days of habituation in a completely randomized design with three dietary treatments and 10 replications, and a forage: concentrate ratio of 20 to 80%. Experimental diets included a control diet (without buffer), a basal diet with 1% sodium bicarbonate, and a basal diet with 1% mixed buffer. Daily feed intake, monthly weight gain, and digestibility were measured. The experimental diets did not affect feed intake, weight changes, and digestibility. The best feed conversion ratio for bulls was in treatment of diet containing the mixed buffer supplement (P<0.05). Daily weight gain was higher in bulls fed with the combined buffer than that of the control group (P<0.05). Rumen ammonia nitrogen was higher in the control group than the bulls receiving mixed buffer (P<0.05). The pH of rumen fluid was lowest in the control group, two hours after feeding (P<0.05). The present study results showed that the mixed buffer had a better performance in controlling the rumen acidity of bulls fed with high concentrate diets compared to sodium bicarbonate, especially in terms of improving feed conversion ratio, and it seems to be necessary to add it to such diets.