Genetic variability of growth curve parameters in goats: application of bootstrap techniques.

Abstract

Growth is an important phase in the life of animals which influences the different forms of production such as milk, meat etc. Since a series of weight-age data points are analytically difficult to interpret, it is desirable to study the growth of animals statistically. Inheritance of growth curves is critical for understanding evolutionary change and formulating efficient breeding plans. The genetic parameters are necessary to examine the potential usefulness of the growth parameters as selection criteria. In the present study, four models namely Logistic, Von berttallanffy, Gompertz and Weibull models are fitted to the body weight data of the goats of 142 animals. The Von bertalanffy model comes out to be the best model for the data under consideration. To this end, the statistical properties of the growth curve parameters are discussed by using bootstrap techniques and the distributions of these genetic parameters are found to be non-normal. The genetic correlation between the mature weight and maturity rate is found to be moderately negative correlated which indicates the selection of animals having higher maturity rate could lead to lighter mature weight. The heritability of mature weight is found to be highly heritable indicating the mature weight can be used for selection purposes.