The Influence of Grape Skin Flour on Reproductive Performance in Botoşani Karakul Rams

The present research aimed to analyze the influence of dietary supplementation with grape skin flour (GSF) in rams on body weight, body condition, semen quality, plasma testosterone levels, behavior, and fertility. The biological material consisted of four groups of rams (GSF0, GSF30, GSF60, and GSF90), with each group comprising six adult individuals. The experimental period lasted 60 days and was carried out prior to the onset of the mating season. During this period, the experimental factor was represented by the supplementation level: GSF30 received 30 g GSF/kg dry matter (DM), GSF60 received 60 g GSF/kg DM, while GSF90 received 90 g GSF/kg DM. Although no significant differences in live body weight (LW) were observed among groups at the beginning of the mating period (MP), the additional supplementation with GSF supported a more consistent accumulation of body reserves. As a result, at the onset of the mating season (MS), body weight increased, though with different intensities: by 0.77% in L0 and by more than 6% in GSF90, with the difference between L0 and GSF90 being highly significant at p ≥ 0.01 (p value = 0.0028). Furthermore, GSF administration induced highly significant differences between GSF0 and GSF60 in body condition score (p ≤ 0.01), and high significant differences (p ≤ 0.001) between GSF0 and GSF90 in testicular circumference. Regarding ejaculate volume, differences were highly significant (p ≤ 0.01) only between GSF0 and GSF60, whereas sperm motility showed significant differences (p ≤ 0.05) between GSF0 and GSF60, and highly significant differences (p ≤ 0.001) between GSF0 and GSF90. The fertility of the rams, assessed by the total number of ewes fertilized, showed highly significant differences (p < 0.01) between GSF0 and GSF60, as well as between GSF0 and GSF90.