title: Morphological variation in the testes and accessory sex organs of Australian rodents in the genera Pseudomys and Notomys.
abstract: The relative size and histology of the testes of sexually active adult Pseudomys and Notomys differed markedly between species. Average weight of testes (as % of body wt) ranged from about 3% in P. australis and P. nanus to about 0.15% in most Notomys. In the testes of most species, interstitial tissue was relatively sparse, but in P. apodemoides, P. delicatulus and P. hermannsburgensis it was abundant and consisted of a mass of lipid-rich epithelioid Leydig cells. Seminiferous tubule diameters were similar in all species, but epididymides ranged from about 500 mg in weight (about 1% body wt) in P. australis to about 20 mg (about 0.05% body wt) in most Notomys. Likewise numbers of spermatozoa in the paired cauda epididymidis ranged from about 500 x 10(6) in P. australis and P. nanus to about 2 x 10(6) in 3 of 4 Notomys species.
mesh_terms: D000818:Animals; D004822:Epididymis / Q000033:anatomy & histology; D005837:Genitalia, Male / Q000033:anatomy & histology; D007985:Leydig Cells / Q000166:cytology; D008297:Male; D009115:Muridae / Q000033:anatomy & histology*; D009929:Organ Size; D012671:Seminiferous Tubules / Q000033:anatomy & histology; D013076:Sperm Count; D013737:Testis / Q000033:anatomy & histology*