Breeders focus on selecting parents to increase the average productivity of future generations. Phenotypic records of economically important traits on which parents are selected are usually quantitative in nature and are influenced by both genetics and environmental factors. However, parents pass on only their genes to their progenies and not environmental influences. For selecting parents, therefore, the important job for breeders is to disassociate environmental influences from phenotypic records and estimate what animals can transmit to their progenies. The genetic worth of animals in terms of what they can transmit to their progenies is expressed in terms of breeding values (BV) or probable transmitting ability (PTA). BV is simply twice of PTA. The question then is how to estimate BV or PTA of animals. As all economically important traits are influenced by both environment and genetics, first phenotypic records of the animals available for selection are corrected for environmental factors and the resultant values are then used for estimating breeding values making use of relationship among individuals. Though breeding value can be estimated for an individual animal, it can only be estimated with data from a group of animals. In this paper, first the statistical procedure used for estimating breeding values of bulls put under test and all females recorded in progeny testing programs implemented under the National Dairy Plan is described in simple terms. In the second part, all common questions raised by persons involved in selection of bulls for semen production on the procedure used in the estimation of breeding values and the advantages of using BVs for selection of parents over phenotypic values are answered in simple language..........
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