Effects of Saccharomyces cerevisiae on Hematological and Physiological Parameters in Sheep
DOI:
https://doi.org/10.48165/ijapm.2026.42.1.9Keywords:
Saccharomyces cerevisiae, Awassi sheep, hematology, biochemistry, probiotics, feed additives, IraqAbstract
The objective of this research was to evaluate the impact of adding S. cerevisiae to the diet of Awassi sheep on hematological and physiological measures. The subjects were 40 male, healthy Awassi sheep aged 8-10 months with average body weight (BW) of 32.5 ± 2.3 kg. There were 2 equal groups; one received a basal diet (the control group) and the other received the basal diet and S. cerevisiae added to their diet at 5 grams per day (treatment group) for a period of 90 days. Blood samples collected on days 0, 30, 60 and 90 were analysed for both hematological and biochemical parameters. The addition of S. cerevisiae to the diet significantly increased red blood cell count, concentration of haemoglobin, and packed cell volume compared to the control group at each of the three weeks’ sampling time. In addition, white blood cell counts and their differential counts were also significantly higher for the treatment than for the control group. Biochemically, the treatment group had significantly higher concentrations of total protein, albumin and globulin, while their concentrations of cholesterol and low density lipoprotein (LDL) were lower than the control group. Enzyme activity for aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were similar between both groups and within the normal range of activity, indicating no potential for hepatotoxicity. In a fasting state, the treatment group had significantly lower glucose concentrations compared to controls, indicating improved glucose metabolism as a result of the addition of S. cerevisiae to their diet. Results of this study support that dietary supplementation with 5 grams of S. cerevisiae per sheep per day positively affect both the hematological profile and the physiological parameters of the Awassi sheep when raised under the Iraqi environmental conditions.
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