Data were weights of F1 calves and weaning weights of top-cross progeny from sires and maternal grandsires of 13 breeds. Three analyses were performed on each trait to obtain estimates and standard errors of breed effects needed to calculate across-breed EPD and accuracies. Model (R) for records of F1 progeny contained fixed effects for birth year and date of birth, sex, age and breed of dam, a...

Several sheep fetuses were thymectomized, and their tails were removed at 58 to 65 days of gestation for tissue culture. Bovine leukemia virus (BLV) antigens were detected in serial culture of tissues from fetuses whose dams and sires were both BLV positive. However, no BLV antigens were detected in serial cultures of tissues from fetuses whose dams were negative but whose sire was positive. Pr...

Genetic and environmental factors that might affect gestation length (GL) were investigated. Data included information from >11 million parturitions from 1999 through 2006 for 7 US dairy breeds. Effects examined were year, herd-year, month, and age within parity of conception; parturition code (sex and multiple-birth status); lactation length and standardized milk yield of cow; service sire; co...

average age distribution and generation interval were investigated in four different selection pathways. i.e., sire of future sires (ss), sire of future dams (sd), dam of future sires (ds) and dam of future dams (dd). young bulls pathway (yb) is also considered as a path that affects the generation interval in sd pathway when using progeny testing program. data were collected from animal breedi...

Field records from the American Simmental Association were used to estimate genetic parameters for direct and maternal effects of traits associated with dystocia. Estimates of the additive genetic variances of direct and maternal effects and of the additive genetic covariances of direct and maternal effects were calculated by equating the sire variance component, maternal grandsire variance com...

Estimates of genetic parameters resulting from three different models for birth weight, weaning weight, yearling weight and total gain were compared. Data consisted of 823 Holstein-Friesian animals progenies of 25 sires and 459 dams in a single herd. The MTDFREML programs were used to estimate heritabilities, predicted transmitting abilities (PTA) and genetic correlations. The three models comp...

For estimation of dominance effects and dominance variance, the inverse of a dominance relationship matrix is required. Dominance effects can be partitioned into sire x dam or sire x maternal grandsire subclass effects that are inherited and residuals within subclass that are not inherited. The subclass effects have immediate use in predicting performance of offspring from prospective matings. ...

Performance records from 1982 to 1992 on 1365 calves for birth weight (BW) and 1492 calves for weaning weight (WW) were analyzed to estimate relationships of purebred sire expected progeny difference (EPD) values for BW and W W to actual crossbred progeny performance. Sires of the calves were Polled Hereford, Simmental, Angus, Salers, Tarentaise, or Charolais. The pooled-across-breed regression...