SU Jianping，ZHANG Yanming，LTU Jike
Abstract: Many researchers can not distinguish between the two terms, instantaneous growth rate and geometric growth rate. They use the following equation of calculating geometric growth rate to calculate animal’ s postnatal instantaneous growth rate: IGR = lnW2-lnW1/t2-t1This misuse began in 1945 when Brody wrote the paper,“Time relation of growth of individuals and populations”, and was repeated by Lackey (1967). Since then, more and more researchers have repeated the same mistake. In this paper, the authors redefine the instantaneous growth rate as the first derivative of given measurements to time, that is IGR =dW / dt Here, W may be any measurement such as body weight, tail length, and so on.. The authors recommend procedures of calculating the instantaneous growth rate. First, the growth model should be established by fitting a sigmoidal equation to the observed growth data because animal’ s growth in most cases is sigmoidal. Second, find the first derivative, the equation representing the relationship between instantaneous gmMh rate and time. Third, use the equation to calculate instantaneous growth rate. Table 1 gives out the equation of calculating instantaneous growth rate for some growth models in common use. To show how to calculate instantaneous growth rate by the above procedures, growth data of body weight of male striped hamster ( Cricelulus barabensis) are used as examples, and the results are given out in table 2.
Instantaneous growth rate,
Geometric growth rate,
苏建平，张堰铭，刘季科. 动物瞬时生长率的概念和计算方法[J]. .
SU Jianping，ZHANG Yanming，LTU Jike. ANIMAL' S POSTNATAL INSTANTANEOUS GROWTH RATE AND IT' S CALCULATION[J]. .