The High Testosterone Concentrations of the Bucks Used in the "Male Effect" Is Not a Prerequisite for Obtaining High Ovarian Activity in Goats from Mediterranean Latitudes.

Testosterone Concentrations, Odor, Scrotal Circumference, and Sexual Interactions with... Time had a marked effect on the plasma testosterone concentration ( I p i < 0.01), as did the interaction of time × buck photoperiod treatment ( I p i < 0.01), the interaction of time × agonist ( I p i < 0.01), and the interaction of time × buck photoperiod treatment × agonist ( I p i < 0.01) (Figure 4A,B). In Experiment 1, the results demonstrate that contact with females induces a rapid rise in the testosterone concentrations of the bucks exposed to a natural photoperiod; however, this contact did not modify the testosterone concentrations of the photostimulated bucks. In general, the testosterone concentration of both groups, used or not, was similar for the entire experiment, except when the bucks were introduced to the females (25 March), at which time the testosterone concentrations of the bucks used increased and decreased rapidly (Figure 1B). Testosterone Concentrations and Sexual Behavior Time had a marked effect on the plasma testosterone concentration ( I p i < 0.001), as did the interaction of time × buck photoperiod treatment ( I p i < 0.001) (Figure 1A). [Extracted from the article]