Performance testing--The systematic collection of comparative production information for use in decision making to improve efficiency and profitability of beef production. Differences in performance among cattle must be utilized in decision making for performance testing to be beneficial. The most useful performance records for management, selection, and promotion decisions will vary among purebred breeders and for purebred breeders compared with commercial cattle producers.

Phenotype--The visible or measurable expression of a character; for example, weaning weight, postweaning gain, reproduction, etc. Phenotype is influenced by genotype and environment.

Phenotypic correlations--Correlations between two traits caused by both genetic and environmental factors influencing both traits.

Polled--Naturally hornless cattle. Having no horns or scurs.

Pounds of retail cuts per day of age--A measure of cutability and growth combined, it is calculated as follows: cutability times carcass weight divided by age in days. Also, it is reported as lean weight per day of age (LWDA) by some associations.

Possible change--The variation (either plus or minus) that is possible for each expected progeny difference (EPD). This measurement of error in prediction or estimation of EPD decreases as the number of offspring per sire increases.

Prepotent-The ability of a parent to transmit its characteristics on its offspring so that they resemble that parent, or each other, more than usual. Homozygous dominant individuals are prepotent. Also, inbred cattle tend to be more prepotent than outbred cattle.

Progeny records--The average, comparative performance of the progeny of sires and dams.

Progeny testing--Evaluating the genotype of an individual by a study of its progeny records.

Puberty--The age at which the reproductive organs become functionally operative and secondary sex characteristics begin to develop.

Purebred--An animal of known ancestry within a recognized breed that is eligible for registry in the official herdbook of that breed.

Qualitative traits-Those traits in which there is a sharp distinction between phenotypes, such as black and white or polled and horned. Usually, only one or few pairs of genes are involved in the expression of qualitative traits.

Quantitative trait--Those traits in which there is no sharp distinction between phenotypes, with a gradual variation from one phenotype to another, such as weaning weight. Usually, many gene pairs are involved, as well as environmental influences.