• HOGER M. HIDAYET Dept. of Pathology and Microbiology., College of veterinary medicine, University of Duhok
  • KAMAL N. MUSTAFA Dept. of Animal Production, College of Agricultural Engineering Sciences, University of Duhok
Keywords: Quercus aegilops, Digestibility, Sheep, Goat.


This study aimed to examine the response of sheep and goats to dietary effects of feeding different
levels of oak (Quercus aegilops) acorns in terms of nutrient digestibility, nitrogen balance, rumen function
and some serum metabolites. The study was conducted over 4 periods each of 15 days; in each period,
rams and bucks were allocated to one of the dietary treatments (control, 5, 10 and 15% oak acorns). Rams
and bucks exhibited different responses to the effects of dietary levels of oak acorns. The digestibility
coefficient of DM was reduced in both rams and bucks upon feeding acorns, but this decline was
significant (P≤0.05) only in rams fed 10 and 15% acorns as compared to rams fed control. Also, the rams
and bucks showed numerical decrease in digestibility coefficients of OM, CP, CF, and NPN. The
experimental treatments had no effects on nitrogen balance parameters. Bucks exhibited significantly
(P≤0.05) higher concentrations of rumen ammonia-nitrogen before, 4 hours and 6 hours after morning
feeding. The rumen pH value was significantly (P≤0.05) by the animal species only at the time before
morning feeding. The serum metabolites were not affected by the level of acorns in the diet. The results of
this study indicate that goats are superior in digesting diets containing oak acorns up to 15%.


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