伊犁鼠兔繁殖生物学的初步探讨

A Preliminary Exploration on the Reproductive Biology of lli Pike

作者于1987～1991年对伊犁鼠兔繁殖生物学进行了初步研究。结果显示,伊犁鼠兔具有年繁殖两胎的时间和可能,第1胎约产于6月初,第2胎约在7月底或8月初。由于其种群密度低,栖息环境恶劣,有些雌体可能失去交尾机会。在捕获的4只雌性成体中,仅1只参加过当年的繁殖,也许部分雌体每年仅产1胎。在所见的21只鼠兔中,雌雄性比为1∶0.8,未成年体鼠兔仅占28.57%。

This paper reports the preliminary study of the reproductive biology of the Ili pika (Ochotona iliensis Li et Ma, 1986) in Xinjang from 1987 to 1991. As the pika has a limited distribution area and a sparse number, the data were obtained by (1) observation in the wild, (2) feeding in artificial condition, (3) check up the captched animals, and (4)microscopic examination of the gonad section, etc. During the all study period, only one juvenile pika was observated in September and 3 subadult pikas were found in July. The active frequency associated with eatrus in early May is more than other months, and at that time microscopic examination of the ovary sections showed a co(?)siderable number of mature follicle in the gonad. It may be seen that the pika had come into breeding period in early spring, and it has possibility and enough time to breed two litters in a year. It was conjectured that the; first litter borned in early June. and the second litter in late July or in early August. As the pika's population quantity is very low and habitat conditions are very hard, some of the female pikas may be lost any opportunity of copulation, so that only a quarter adult females were take part in reproduction, and some females perhaps breed only one litter in a year. The sex rate (♀/♂) is 1:0.8 and the percentage of young and subadult are 28.57% with the captched and observed pikas.