engleski

The influence of live yeast cells (Saccharomyces cerevisiae) on the performance of grazing dairy sheep in late lactation

A feeding trial was conducted in order to evaluate the influence of live yeast cells (Saccharomyces cerevisiae) on milk production and composition, and on blood parameters in late lactation. The experiment was performed on forty Croatian crossbred dairy sheep divided into a control group without live yeast cells (CD = control diet) and the experimental group with live yeast cells in the diet (YC = diet with Saccharomyces cerevisiae). The diet was based on pasture and concentrate containing corn (66.3%), soybean meal (18.7%), bran (6%) and alfalfa meal (4%). Supplementation with live yeast cells significantly increased the total milk yield in the 23rd week (P<0.5) and in the 27th week (P<0.5). Morning milk yield was also significantly increased in that period. All other values concerning milk yield did not differ significantly between treatment groups. The average amount of milk during the experimental period was higher in the YC group than in the CD group (604.60 ± 83.21 and 630.28 ± 92.34, for control and yeast-supplemented group, respectively) but without any significant difference (P>0.5). The chemical composition of the milk was not influenced by the treatments with the exception of milk fat that was significantly higher in YC group. Blood parameters were not affected by the treatment. We conclude that supplementation with live yeast cells, under the conditions of our experiment, had no statistically significant beneficial effects on the performance of dairy ewes during late lactation. High concentrate diet, the stage of lactation and high temperatures may have decreased the response to live yeast cells.

live yeast cells; sheep; milk yield; milk composition; blood parameters

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