Age-Related Changes in the Gross Morphology and Morphometry of the Testis and Epididymis of the African Greater Cane Rat (Thryonomys swinderianus)

Abstract

This study evaluated age-related changes in the gross morphology and morphometry of the testis and epididymis of the African Greater Cane Rat (AGCR). Twenty pathogen-free cane rats used for this study were randomly divided into 4 groups; Group I - prepubertal (≤4 months), Group II - pubertal (>4≤12 months), Group III - adult (>12≤30 months), and Group IV - aged (>30 months) of 5 animals each. On day 8th of acclimatization, testis and epididymis were harvested from sedated cane rat, described grossly and standard morphometric parameters (length, width, circumference, weight, and relative weight) determined. Gross morphological observations in the testes of all the different age categories showed similar characteristically cream to milky-white coloration and ellipsoidal shape. The epididymis in the different AGCR group uniquely presents the same inverted S-shaped outline, loose attachment to the testis, and less distinct division into caput, corpus, and cauda segments. Testicular and epididymal morphometric parameters were significantly reduced in the prepubertal cane rat relative to other groups. The parameters consistently displayed an age-dependent increment with the advancing age of the animal. In conclusion, this study has shown that both testicular and epididymal gross morphometrics increase with age advancement and perhaps might be linked to the varying functional reproductive status of the different age groups of the African greater cane rat.