Contributions of Ovum Cytoplasm and Uterine Environment and Postnatal Environment to Maternal Effects in Beef Cattle

Authors

Keith E. Gregory, U.S. Meat Animal Research Center
Ralph R. Maurer, U.S. Meat Animal Research Center

Date of this Version

1993

Document Type

Article

Comments

Published in Beef Research Program Progress Report (1993) No. 4 (Part 1): 6

Abstract

Any contribution or influence on offspring phenotype attributable to its dam, exceeding the inherited sample half of the dam's nuclear genes, is a maternal effect. Maternal effects can be classified into prenatal (e.g., cytoplasmic and uterine components) and postnatal [e.g., lactation, method of rearing (early weaning), plus other postnatal maternal components]. This experiment was designed with two objectives. The first objective was to determine the relative contributions of ovum cytoplasm and uterine influences on prenatal maternal effects by use of embryo transfer (ET). The second objective was to estimate breed differences in prenatal and postnatal maternal effects combined by evaluating differences between reciprocal crosses and the effects of early weaning and to separate the effects of prenatal maternal influences from postnatal maternal influences.