The birth period is very important when estimating the risk of a long-lost kitten.
The gestation period of a bear cat is usually 3 to 5 months. The shortest gestation period is 93 days and the longest is 163 days in the Shirahama Wildlife Park, and the difference is more than 2 months. This difference is caused by a special reproductive system in which the bear cat has a "delayed bedding" *.
Delayed implantation: A form of implantation that occurs in some mammals. The embryonic bubble after fertilization goes away in the child's palace, and after certain conditions, the embryo is implanted and forms a placenta. This phenomenon appears in mammals such as bears and marsupials.
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Unequal female big bear cat gestation period length
Mother亲：梅梅 Mother亲：良浜 Year of production gestation period Year of production gestation period 2000年 103天 2008年 138天 2001年 93天 2010年 136天 2003年 109天 2012年 129天 2005年 139天 2014年 136天 2006年 117天 2016年 136天 2018年 128天 2020年 163天 average 112天 average 134天 shortest 93天 shortest 128天 the longest 139天 the longest 163天 -
产仔日期预测表
mother Year of production From从出现该现象到产仔经过时间（天) Less (粪便量减少 (少于5kg) urinary impregnation二醇Content达峰 Sleep time continues to increase up and down 2000年 24 20 26 2001年 21 23 14 2003年 21 22 24 2005年 25 21 25 2006年 22 22 23 Mean±Tagged Difference 22.6±1.8 21.6±1.1 22.4±4.8 good beach 2008年 21 20 31 2010年 23 25 31 2012年 23 27 31 2014年 27 20 29 2016年 22 21 27 2018年 22 23 27 2020年 21 17 23 Mean ± standard deviation 22.7±2.1 21.9±3.4 28.4±3.0 Ume-ume and Rahama Mean±Tagged Difference 22.7±1.9 21.8±2.6 25.9±4.8
Since 2010, the survival rate of young polar bears under circling conditions has increased to 88%. This is mainly due to the fact that the mortality rate is relatively high during the first cycle after birth, and because of this, a reliable parent-offspring management technique was established. The time between birth and the last day of life is a very important factor in determining when a big bear cat will reach maturity. The Shirahama Wildlife Park has used three main indicators to estimate the bear cat's gestation period.
- (1) The amount of stools is rapidly decreasing (5 kg).
- Urine impregnation density (PDG) content reached its peak
- (3) Continuous increase in sleeping time
In these indicators, the following appear: increased sleeping time, decreased amount of feces, and increased urinary molar content. When these three indicators are estimated, the last time a female shows signs of emotional urgency, euphoria, and licking behavior (舔行), she is considered to be in full-term labor. We will try to estimate the production period and establish an appropriate environment for the mother and her cubs, and prepare the cubs for birth.
Changes in Sleep and Eating Time (2020 Ryouhama Nyanzai)
Changes in the amount of feces and impregnated dichloride in urinary fluid (2020 Ryouhama products)
