Kuroiwa J, Imamichi T
Jikken Dobutsu. 1977 Jul;26(3):213-22. doi: 10.1538/expanim1957.26.3_213.
The paper deals with observations on growth and reproduction of the chinchilla in recent 4 years started from 1966 at this laboratory. There were large variations in age of vaginal opening (less than 71 days-308 days) with an average of 173.2+/-57.6 days in 45 females. The average length of 100 oestrus cycles in 24 females was 35.7+/-7.9 (15-62) days. The mean period of 5 gestations in 5 females was 110.4 (108-112) days. Eighty-one out of 123 litters were born between March and August during 3 years, and parturition never occurs in December. The most suitable season for reproduction of chinchillas may be from January to April, and a summer anoestrous seems to be present in August to early September as reported by Weir. The litter size ranged from 1 to 4 with a mode of 2 (46.3%) and an average of 1.90+/-0.76. More male kids were produced at birth at this laboratory, and sex ratio was 133.7 (98 females and 131 males). In 1973, 37 chinchillas gave birth to 71 kids with an average litter size of 1.92, and 59 of them were successfully weaned (1.59 per litter). Of these kids, 50 (1.35 per liter) attained 240 days of age (adulthood). Among 91 subjected to investigation for causes of death, 23 (25.3%) were dead during newborn period, and 9 and 5 adults were dead of malocclusion (9.9%) and the prolapse of rectum respectively.
本文论述了自1966年起在本实验室对近4年中龙猫生长和繁殖情况的观察。45只雌性龙猫的阴道开口年龄差异很大（小于71天至308天），平均为173.2±57.6天。24只雌性龙猫的100个发情周期平均长度为35.7±7.9（15 - 62）天。5只雌性龙猫的5次妊娠期平均时长为110.4（108 - 112）天。在3年里，123窝中有81窝出生于3月至8月，12月从未发生过分娩。龙猫繁殖的最适宜季节可能是1月至4月，并且如韦尔所报道的，8月至9月初似乎存在夏季发情休止期。每窝产仔数为1至4只，众数为2只（46.3%），平均为1.90±0.76只。本实验室出生时雄性幼崽更多，性别比为133.7（98只雌性和131只雄性）。1973年，37只龙猫产仔71只，平均每窝产仔数为1.92只，其中59只成功断奶（每窝1.59只）。在这些幼崽中，50只（每窝1.35只）活到了240天龄（成年）。在接受死因调查的91只中，23只（25.3%）在新生期死亡，9只成年龙猫死于错牙合（9.9%），5只成年龙猫死于直肠脱垂。
