Testicular and Epididymal Responses to Growth Variation in Prepubertal Male Peranakan Etawah Goats

Abstract

This study aimed to evaluate the influence of growth rate on the reproductive characteristics of prepubertal male Peranakan Etawah (PE) goats. Six goats aged 7–8 months were divided into two groups based on body weight: high-growth (n = 3) and low-growth (n = 3). The evaluated parameters included the testicular and cauda epididymis dimensions, sperm concentration, and sperm morphology. High-growth goats exhibited greater testicular length (P > 0.05) and significantly wider testes (P < 0.05) than low-growth goats. The relative testicular length to body weight was lower in high-growth goats (0.20 cm) than in low-growth goats (0.29 cm; P < 0.05), whereas the relative testicular width did not differ significantly between groups (P > 0.05). Similarly, no significant differences were found in the cauda epididymis length, width, or their relative ratios to body weight (P > 0.05). Although not statistically significant, high-growth goats showed higher sperm concentration and lower total sperm abnormalities than low-growth goats. The proportion of sperm head abnormalities was slightly higher in high-growth goats (4.99%) than in low-growth goats (0.49%), whereas midpiece (0.87% vs. 0.89%) and tail abnormalities (53.77% vs. 62.73%) were lower in high-growth goats than in low-growth goats. In conclusion, accelerated growth during the prepubertal stage in male PE goats is associated with increased testicular size, although this improvement does not significantly affect sperm quality at this developmental stage.