The influence of diet supplementation with Saccharomyces cerevisiae or Saccharomyces cerevisiae plus Aspergillus oryzae on milk yield of Cilentana grazing dairy goats

The trial was performed on 36 goats (50.3 ± 2.6 kg body weight) having free access to pasture, constituted by 60% Leguminosae and 40% Graminee, equally divided into three groups (CTR, SC, AS) homogeneous in parity and milk production at the previous lactation. Concentrate of groups SC and AS was supplemented with 20 g/head/day of Saccaromyces cerevisiae and Aspergillus oryzae fermentation extract plus Saccaromyces cerevisiae respectively, while group CTR was used as control. Average milk yield did not differ statistically among the groups (g/head/day 1480 vs 1630 vs 1630 for CTR, SC and AS, respectively). By contrast, milk fat percentage was significantly (P<0.01) lower in SC and AS compared to CTR. Group AS showed significantly (P<0.01) lower milk protein percentage than CTR. Lactose was unaffected by treatments. Finally, milk fatty acid profile was unaffected by treatments. In conclusion, the supplementation of diet with live yeast and fungal extracts does not appear useful when goats are fed on pasture.