The objective of this present investigation was undertaken to study the testicular and epididymal biometrical characteristics in Algerian donkeys throughout the year according to age, body weight and seasonal changes. The study was conducted from February 2019 to January 2020. A total of 24 sexually mature donkeys (Equus asinus) were selected randomly. The testis and epididymis were collected after slaughter of donkeys and separated from the conjunctive and adherent tissues. The epididymis has been carefully removed at the testicular junction. In total, 10 biometric measures were selected and performed. Our results revealed that there are significant differences (P<0.05) between groups in most biometrics values. All biometric parameters varied throughout the year and were affected by the season. Significant differences of the GSI and SC values (P<0.05) were observed in different age groups and seasons. On the other hand, no significant differences were observed between the body weight categories of donkeys. The analysis of the correlation coefficients between the biometric values shows high positive correlations, ranged between 0.98 and 0.72 (P<0.001). There was a high positive correlation between age and all the parameters, ranged from 0.85 to 0.61 (P<0.001). However, there were low negative correlations between season and; testicular and epididymal biometrics. It is the first investigation that describes the male reproductive organs in donkeys of the Algerian race (Equus asinus), on the basis of biometric testicular and epididymal measurements. Our results showed that the essential differences were noted between some biometric parameters and the age, season and body weight of donkeys. In addition, the correlation coefficients were supported between biometric measurements and these factors. However, other approaches are necessary to undertake, such as histology of reproductive organs and hormone measurement, for a deeper understanding of the physiology of reproduction in donkeys.
KEY WORDS: Testis; Epidydimis; Biometry; Donkeys; Equus asinus.
AISSANOU, S. & AYAD, A. Influence of age, body weight and season on testicular and epididymis biometrics in donkeys (Equus asinus). Int. J. Morphol., 38(5):1434-1443, 2020.