The JiNing Gray goat, a first-class strain cultivated in
the southwest of Shandong province, China, has early sexual
maturity and high progenitive rate. According to China
Goat Strains, compared with other breeds, the JiNing Gray
goat has the strongest fertility (from an average of 2.94
lambs up to 6–7 per breed) (Tu, 1989). The JiNing Grey goats
reached puberty (time to first ovulation) when 2 months
old, which was 4 months earlier than that of Hu sheep
(6 months of age) (Chen et al., 1989).