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This study explores how age and seasonal changes impact semen characteristics and reproductive behavior in Carpatina breed bucks. Males were divided into three age groups: young (14–23 months; L14), adult (3–4 years; L34), and older (5–6 years; L56). Scrotal biometry was determined using a measuring tape, and testicular volume was evaluated by fully submerging the testes in a water-filled container and measuring the displaced water. Semen analysis was conducted on samples collected each season, with volume, color, and acidity being assessed. The evaluation of specific semen characteristics (motility, sperm concentration, normal spermatozoa) was conducted using a Computer-Assisted Semen Analysis (CASA) system, and testosterone levels were measured in blood samples collected at the start of each season. Behavior and sexual reflexes were evaluated based on mating desire and the bucks’ reaction to the presence of females. Key findings indicate that testicular volume varies significantly with both age and season, with the most pronounced differences between younger bucks and the older groups, especially during autumn. Semen quality parameters such as ejaculate volume, sperm concentration, and motility also showed seasonal fluctuations, with younger bucks having lower sperm concentrations. Testosterone levels were observed to increase with age, peaking in autumn. Behavioral observations revealed that younger bucks exhibited less intense sexual activity, although this improved during autumn. Additionally, a significant correlation was identified between body weight and testicular volume in adult bucks (R = 0.942, p-value = 0.016 for L34; R = 0.797, p-value = 0.022 for L56), suggesting that age plays a crucial role in reproductive potential. Our findings highlight that, while bucks are capable of year-round reproduction, autumn provides optimal conditions for semen quality and reproductive performance. This research has valuable implications for optimizing breeding programs, contributing to genetic advancement, and improving management strategies in goat farming, especially within temperate continental climates.

This study aims to analyze the influence of an improved diet with vitamins and minerals (VM) on the live weight, body condition, quality of sperm, behavior, and fertility of rams. The biological material comprised two groups of rams (L1—control and L2—VM supplemented), each consisting of 15 individuals. After a complete one-year cycle, they received different dietary treatments at the beginning of the preparation for the reproduction period. Although in the onset of the mounting period (SM), no significant differences were observed for live weight (p > 0.05), providing supplemental feeding of a VM complex allowed a better capitalization of body reserves, and, consequently, the rams’ groups differed significantly by the end of mating season (FM), for live weight (+4.1%; p < 0.001) and body condition score (+15.9%; p < 0.05). Adding vitamins and minerals to the L2 diet also improved sperm color (p < 0.001), sperm concentration (+11.8%; p < 0.01), live spermatozoa (+2.6%; p < 0.001), and decreased abnormal spermatozoa proportion (−7.0%; p < 0.01). The increase in the scrotum circumference in L2 (+4.57%) suggests that VM supplements improved testosterone secretion, spermatogenesis, and ejaculate volume (+10.20%; (p < 0.001), with a positive impact (p < 0.001) on mating behavior, on the gestation installation (+11.2%) and on the number of obtained lambs (+14.0%), as well as on the key economic indicators (+13.8% incomes per ram).

The aim of this research was to study the impact of supplementary feeding on reproductive traits in sheep. Two groups, L1 (control) and L2 (experimental treatment), of adult females aged between two and six years belonging to the Botosani Karakul sheep breed were formed. The experimental treatment group (L2) received supplementary feeding 25 days prior to mating. Improvements in body condition and significant increases in live weight occurred by the time of mating in those ewes that had been flushed (L2) (p < 0.01 vs. L1). The number of lambs per individual parturition was influenced by the body condition score (BCS), especially in females with a BCS of 2.0. The total number of weaned lambs in females with a BCS of 2.0 differed in comparison to that of females with a BCS of 2.5 or 3.0. All results highlighted that supplementary feeding applied to ewes prior to mating affected their reproductive and economic performance, translating to an increased live weight of the litter at weaning in the L2 group (p < 0.01 in lambs from BCS 2.0 ewes and p < 0.001 in lambs from BCS 2.5 to 3.5 ewes).