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This article presented the results of “buck effect” in local Greek genotypes. These observations were made in an experimental station and in private flocks where sexual activity of males and females were determined. Testis volume increased two-fold from January to July. Intensity of sexual behaviour also rose in March when five of 14 bucks displayed sexual behaviour. All five bucks remained seasonally active throughout the experiment. The volume of their ejaculate increased from 0.8 to 1.2 ml, but the total counts of spermatozoa and the concentration decreased. Motility and viability remained high (4% and 70–80%, respectively) during the full experimentation period and did not show significant seasonal differences. Ovarian activity of some females continued up to March but all females were in ovarian inactivity throughout spring. Despite this 100% inactivity, all ovulated after buck introduction. This suggested that the breeding period could be advanced using “buck effect”, with males that where not at the maximum of their sexual activity.

In France, goat Artificial Insemination (AI) plays an important role in the milk intensive production system to control reproduction and, in conjunction with progeny testing, to improve milk production. About 60 000 goats were inseminated in 1996, 95% of them before the breeding season with deep frozen semen after induction of oestrus and ovulation by hormonal treatment. The efficiency of this method was about 65% of kidding rate. In 1996, 290 000 lactating goats were officially recorded. The selection scheme, aimed at improving protein yield and protein content, benefits from the sampling program for young AI buck. AI allows higher selection intensities for male selection, adequate genetic evaluations through genetically connected herds, and monitoring and selection of bucks for major genes like the αs1-casein gene. In order to further develop AI, a cooperative action between the partners of the dairy goat industry (Research, Agricultural extension and Farmer organizations) has operated since 1992 with the aim of reducing the variability of fertility rates. This program includes improvement of the control of reproduction by hormonal treatments, AI conditions, embryonic mortality and pseudopregnancy.