The effects of microbial inoculation of corn silages on animal performance were evaluated using nine primparous lactating dairy cows in a 3×3 change over design with 21-d periods. Whole plant corn was harvested at the medium dough stage of maturity (30% DM), chapped and ensiled in horizontal silos. The following treatments were applied to the forage: 1) control (contain untreated corn silage), 2) diets containing corn silage treated with a commercial inoculant (Lactisil) and 3) diets containing corn silage treated with an inoculant as a fresh culture produced in laboratory. Dry matter intake (DMI) was significantly affected by treatments (P≤0.05). The cows on laboratory inoculated silage had significantly higher DMI than those on control group (21.89 vs 21.32). There was no significant difference between the treatments on ruminal pH and ruminal NH3-N concentration. Inoculation had no significant effect on milk composition, milk yield and 4% fat corrected milk production. Milk yield and 4% FCM in treatment that were inoculated with laboratory inoculation were 1.3 and 0.65 kg/d greater than from control silage respectively. Also there was no significant effect on blood plasma metabolites. It is concluded that microbial inoculants had minimal effect on the performance of lactating dairy cows.

Keywords