Seasonal variations of sexual activity of local bucks in western Algeria

The aim of the present study was to evaluate the seasonal variation of sexual activity among bucks of local breed (Arbia) in western Algeria. The experiment was carried out using eight bucks aged between 4 and 6 years, a group of males in their pre-puberty age (4 to 6 months) and two females. Animals were kept in a building during one year and fed with a constant ration of wheat and hay with free access to water. Sexual activity was evaluated by scrotal circumference and sexual behaviour analysis. Results showed that the monthly average of scrotal circumference was high during August and September (27.58 +/- 0.16 and 27.67 +/- 0.17 cm, respectively) and low during April and May (25.18 +/- 0.11 and 25.25 +/- 0.17 cm, respectively). Monthly averages of sexual behaviour followed similar evolution. When the season of the year is considered, sexual behaviour and scrotal circumference presented significant variations. The two parameters are maximal during autumn (7.96 +/- 1.28 and 26.89 +/- 0.55 cm, respectively) and go down during winter (6.09 +/- 1.25 and 25.65 +/- 0.27 cm, respectively) to reach minimal values during spring (4.89 +/- 1.66 and 25.41 +/- 0.37 cm, respectively) then they go up during summer. In conclusion, bucks of local breed in western Algeria have seasonal variations of sexual activity in relation to annual photoperiod variation; short days stimulate the sexual activity whereas long days inhibit it.