The objective of this study was to evaluate the variability of growth curves of dairy heifers and estimate genetic parameters. 15066 records taken from birth until 26 months (808 days) on 2754 heifers of Quebec were considered. The pedigree file comprised 10123 animals. The Mixed procedure of SAS with ordinary polynomials was used for simple phenotypic analyses, fitting fixed linear, quadratic and cubic regressions of body weight (in kilograms) on age (in months) as well as random intercept, and random linear and quadratic regressions for each animal. The Wombat program (Meyer, 2007), with Legendre polynomials was used to estimate the genetic parameters by fitting fixed herd-year-season of birth and quartic regression of body weight on age in days, as well as random regressions for quadratic additive genetic and cubic permanent environmental effects. Heritability estimates of body weight ranged from 0.22 at around 70 days to 0.45 at around 210 days. Heritabilities of body weight at birth and 808 days were 0.35 and 0.32, respectively. The additive genetic correlations between body weights at different ages ranged from -0.37 to 1.00. In general, the genetic correlations were higher than the permanent environmental and phenotypic correlations.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 162-176). Also available via the Internet.

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Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaves 106-112). Also available via the Internet.

Thesis (M.Sc.(Agric)(Animal Nutrition)) -- University of Pretoria, 2008. / Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--Madison, 1970. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 109-111).

Thesis (M.S.)--University of Wisconsin--Madison, 1984. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 69-80).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.