Postmortem diagnosis of aspermatogenesis and hypospermatogenesis in the Nigerian Sahel goat by testicular and epididymal sperm cytometry

Apparently healthy male Nigerian Sahel goats (n = 125) aged 18–30 months old and weighing 10–25 kg were selected at slaughter by stratified quota sampling, into 5 groups of 25 each with varying testicular sizes, in order to investigate the occurrence of dyspermatogenesis. Testicular sizes were categorized as very small, small, medium, large and very large using gonadosomatic index values of 1–2, >2–3, >3–4 and >4 g/kg, respectively. Left testes and epididymides were homogenized with formalized normal saline for sperm cell count by manual cytometry. Right testes were fixed in 10% buffered formalin and processed for histopathological examination. Cauda epididymal sperm counts of zero and