Abstract

In order to evaluate the effect of adding butyric acid to whole milk on growth performance and blood parameters of Holstein calves, 36 calves were used in a completely randomized design. The experimental treatments were: 1) control group without any additive (B0); 2) B0 + 4 grams per day of added butyric acid in milk (B4); and 3) B0 + 8 grams per day of added butyric acid in milk (B8). The calves had free access to feed and water during the experiment. Body weight at weaning and end of experiment tended to increase in B4 and B8 compared to B0 (P = 0.08). Average daily gain was significantly (P < 0.01) affected by treatment during the pre-weaning, so that B0 had the lowest daily gain, but no difference was observed between B4 and B8. The starter intake was less in B0 compared to the other two groups during pre-weaning period (P < 0.01), post-weaning, (P = 0.04) and throughout study (P < 0.01), but there was no difference between B4 and B8. The serum concentrations of glucose, total protein and albumin within pre-weaning were not significantly different among treatments, but BHBA concentration was lower in B0 group than in other groups (P < 0.01). There was no difference among treatments in terms of average fecal score. In general, for the first time, the results of this study showed that adding butyric acid to the whole milk can have positive effects on improving performance. Key words: Butyric acid, whole milk, calf, productive performance.