Testicular morphometry and prevalence of cryptorchidism among three goat breeds in Southern Nigeria

This study determined the testicular morphometry of three goat breeds namely: Borno Sahel (BS), Red Sokoto (RS) and West African Dwarf (WAD). Testicular morphometric traits measured were scrotal circumference (cm), length (cm) and weight (kg). In addition, incidence of cryptorchidism was monitored by palpating the scrotum and noting number of descended testes as well as position of non-descended testes in individual goats among the breeds. A total of 90 goats (30 per breed) aged between 1 and 3 years old were used in the study. Data obtained from the study were subjected to one - way analysis of variance (ANOVA) for Completely Randomized Design (CRD). Significant means were separated using Duncan’s Multiple Range Test. Result showed that WAD goat had the highest mean scrotal circumference (23.11cm) and testicular length (14.38 cm) with significant difference (p<0.05). The effect of age showed that 3 years old goat bucks had the highest testicular length (17.25 cm) and testicular circumference (26.97cm) with significant difference (p<0.01), while 1 year old bucks had the heaviest testicular weight (13.9 kg). Correlation analysis showed a strong positive (0.741) relationship between the testicular length, circumference and weight and body weight of the goats. There were comparable results on the effect of age and breed and their interaction on their testicular morphometry. Out of 90 bucks examined, three bucks were found to be unilaterally cryptorchids on the right testis; two in Borno Sahel breed (6.67 %) and one in the Red Sokoto breed (3.33%). The West African Dwarf goats, by reason of their heavier testicles, had better sperm production and storage capacity in the study area than the Red Sokoto and Borno Sahel breeds. The study concluded that the high degree of association between body weight and scrotal length, scrotal circumference and testicular weight of bucks implied that goats can be selected for scrotal traits based on their body weight. Similarly, scrotal morphometry of goat bucks in Calabar is a good indication of their breeding soundness. Key words: Breeding, genetic, goat breeds, sperm production, testicular morphometry, reproduction