著者

鳥居 春己

出版者

奈良教育大学

雑誌

奈良教育大学紀要. 自然科学 (ISSN:05472407)

巻号頁・発行日

vol.59, no.2, pp.15-19, 2010-11-30

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Reproductive traits of the Japanese hare, Lepus brachyurus, were investigated with 196 hares killed either by hunting, pest control or traffic accidents in Shizuoka Prefecture from 1984 to 1993. Average weight of testis started increasing from November, and reached the peak on March, then declined gradually from March to October, and the spermatogenesis ceased both September and October. Although the average weight of ovaries showed similar changes, the change started one month later than the testis. Detectable embryo were found in the samples from February to October. Assuming that breeding season was from first copulation to the last parturition, determined by the age of leverets captured in the wild, in which the whole ages were estimated by the body weight, the duration of the breeding season could be estimated to be 276 days. Embryo size ranged from single to triplets with an average of 1.6 ±0.7. Calculated average annual reproductive potential was 10.1 young per female.