Effects of starch and protein sources of starter on ruminal volatile fatty acids, blood metabolite and body gain of Holstein calves

There is limited information concerning the interaction between grain and protein sources in starter diets on rumen fermentation profile and calf performance. It was hypothesized that calves would respond differently to various grain sources when fed with starter diets containing different protein sources. The objective of current study was to investigate the interactions between grain sources (corn vs barley) and protein sources (soybean meal vs. canola meal) on rumen fermentation profiles and calves’ growth. In a 2 × 2 factorial experiment, 40 calves (5 female and 5 male) were randomly assigned to four treatments to receive starter diets consisting 1. ground corn and soybean meal, 2. ground corn and canola meal, 3. ground barley and soybean meal, and 4. ground barley and canola meal. Volatile fatty acids, blood metabolite and calves’ growth were assessed for 65 days. Corn grain had no significant effect when included by soybean meal and canola meal, but barley grain resulted in higher total volatile fatty acids when canola meal included instead of soybean meal. The lowest starter intake was found for calves received barley-canola meal and the highest was for those received corn-soybean meal. Calves fed with starter diets containing corn soybean meal had greater average daily gain compared with calves fed barley-canola meal. The results revealed that corn grain is better than barley and and soybean meal is better than canola meal for calves starter formulation. The best composition was corn-soybean meal and the worst one was barley-canola meal which had the poorest effect on calves’ growth.