Genetic and Economic Implications of Fetal Effects on the Dam

Abstract

The genetic model for fetal effect on production of the dam is described, and studies on genetic and economic implications are reviewed. The effect on production from the sire of the cowhas 1.58 to 3.02 times as much economic value as the effect from the sire of the fetus. The use of mate records in evaluating a sire in addition to daughter records could increase economic gain from selection by 1 to 2% depending on the variation from sire of fetus. Mate records alone do not appear valuable for sire selection. About 1% of the variation in milk yield appears to be due to the effect of sire of fetus as indicated by a summary of various estimates and from consideration of the data and methods used to obtain the estimates. The correlation between effects of sire of fetus and sire of cow appears to be nearly zero. A method of joint evaluation of bulls as sires of cows or as sires of fetuses is described.

Estimation of Direct and Service Sire Genetic Parameters for Reproductive Traits in Yorkshire

“…With a reported range of 0.3 to 3% of the total variation in NBA, it seems that the service sire has a very small but significant effect on NBA in swine. Van Vleck and Johnson (1980), in a study on the effect of service sire on dairy cattle milk production, found that the service sire accounted for 1% of the variation in milk yield and that the correlation between the service sire and sire of the cow was nearly zero. However, Van Vleck and Johnson (1980) concluded that the genetic and economic implications of the service sire effect were not important probably.…”

Quantitative Genetic Models for Development, Epigenetic Selection, and Phenotypic Evolution

“…A second class of epigenetic effects arises from fetuses prenatally or from offspring postnatally and acts on reproductive characters of the mother. Examples offetal effects include establishment and maintenance of pregnancy (Bazer et al, 1986), milk yield in dairy cattle (Van Vleck and Johnson, 1980), and luteal lifespan in mice (Critser et al, 1980). An excellent example of postnatal offspring effects on the mother is demonstrated by research on Mongolian gerbils (Clark et al, 1990).…”

Plasma estrone sulfate, clinical biochemistry, and milk yield of dairy cows carrying a fetus from a bull or its clone

“…In dairy goats, Engeland et al [27] reported higher serum bglobulin at the beginning, but not later, in pregnancies that ended with fetal losses. In their early review, Van Vleck and Johnson [32] estimated a contribute of about 1% to the variation of milk yield to the effect of the sire, but previous studies suggested that this effect could be up to 8% [33]. Moya et al [34] reported how the sire of fetus affected in a small, albeit real and measurable extent, milk and fat yields, fat percentage, and gestation length.…”