ABSTRACT
Congenital aabnormalities of the male reproductive tract include abnormally shaped testes, fusion of the cranial poles, hypoplasia and agenesis. Usually there are no clinical signs, although aviary birds may be presented for infertility investigation. Diagnosis is by endoscopy, and no treatment is required. Degeneration of the testes is associated with various drugs and toxins. It is diagnosed by endoscopic biopsy or needle aspiration cytology. Orchitis may be bacterial, fungal (extension from fungal air saculitis), mycobacterial (extension from systemic disease) or chlamydial (extension from systemic disease) in origin. Infection occurs by haematogenous spread or via an ascending infection from the cloaca/phallus. Neoplasia of the male reproductive tract is reported in numerous species. Tumours seen include Sertoli cell tumours (most common), interstitial cell tumours, seminomas, teratomas, lymphosarcoma, teratoma and leiomyosarcoma and carcinoma of the ductus deferens and epididymis. Radiology may demonstrate an enlarged testicle and, if a Sertoli cell tumour is present, increased radio-opacity of the bones may be seen.
