Supplementary effect of peppermint (Mentha�נpiperita) on dry matter intake, digestibility, ruminal fermentation and milk production in early lactating dairy cows

The aim of this research was to investigate the effect of peppermint feeding on dry matter intake, nutrient digestibility, ruminal fermentation and milk production in early lactating cows. Four Holstein cows were offered a diet with 5% dried peppermint and four Holstein cows remained on a diet without 5% of dried peppermint on a dry matter basis. The addition of peppermint to feed did not affect dry matter intake, although the eating time of feed was increased by mixing the feed with peppermint. There were no significant differences in the nutrient digestibilities between the two treatments. The ruminal ammonia and volatile fatty acids concentrations were similar in the two treatments, however, peppermint ingestion by cows led to a decrease in ruminal pH. The lowered pH value was within the stable pH condition range. No significant differences in the treatments were observed in milk production or milk composition except for the milk fat content. These results suggest that feeding peppermint to early lactating cows had little effect on their dry matter intake, nutrient digestibility, ruminal fermentation and milk production.