In male Tokara (Japanese native) goats, testis development and the onset of puberty were studied histologically and observing sexual behaviour. Testes weight increased from 36 ± 5.4(S.E.) g (n = 5) at 3 months of age to 126±6.3 g (n = 6) at 12 months. The degree of the testis development differed among kids at 3 months of age and only one of four had produced spermatozoa in the testis. Large number of spermatozoa were always present in seminiferous tubules and epididymal ducts from 4 months of age. The diameter of seminiferous tubules increased from 133 ± 9.9 μm (n = 4) at 3 months to 198 ± 1.0 μm (n = 3) at 6 months with little increase thereafter. Mounting and pelvic thrusts onto a teaser doe started at from 9 to 14 weeks of age. Ejaculated semen contained sperm with good motility for the first time from 17 weeks. The male Tokara goat reaches puberty at around 4 months of age but testis development continues to 12 months. (C) 2000 Elsevier Science B.V.
All Science Journal Classification (ASJC) codes
- Food Animals
- Animal Science and Zoology