Testicular Hypoplasia

• TESTICULAR HYPOPLASIA

Maybe spontaneous or associated with intersex or cryptorchidism. Can occur in all species. Is confined to descended testicles (cf. cryptorchid testes). May be bilateral and/or unilateral. Usually detected at or after puberty because of lowered / lack of fertility. Development of accessory genitalia is normal, i.e. hormone secretion unimpaired.

Aetiology:

1. Genetic factors:sex-linked autosomal recessive gene (Swedish Red cattle).
2. Environmental factors:Zn deficiency,ecological/organo-phosphorous compounds?
3. Hormonal factors:endocrine deficiency.
4. Chromosomal abnormalities:XXY Klinefelters syndrome - all species. Male tortoiseshell cats (XXY).

Gross:small, freely movable in scrotum.
Histologically:mild (<50% of tubules hypoplastic) to severe, seminiferous tubules small lined by Sertoli cells only. No significant inflammatory reaction

Information by kind permission of Professor R W Else