Relativity of growth in laboratory and farm animals: II. Birth weight as apredictor of animal maturity

In this article the growth curves of individual animals for various species were examined to determine the relationship between birth weight and matur e size. For the genotypes studied the birth weight fraction or maturity (Fb ) was found to range from approximately 0.6% to approximately 10% of mature size. Generally, for most species in this study it was found that Fb incre ased as birth weight became larger and the female of the species generally demonstrated a larger fraction of maturity at birth than did the male anima ls of the same breed. Art equation was developed to predict Fb for each gen otype with varying degrees of success. Using the developed equation and the birth weight of an individual animal, a physiologically based estimate of the animal 5 mature size can be obtained.