Genetic parameters including the proportion of variance for the service sire effect were estimated for number of piglets stillborn (including piglets died until 24 h after birth) and number of piglets died from 24 h after birth until weaning in Czech Large White (89 231 litters) and Czech Landrace (28 320 litters) pigs. Both traits were considered to be traits of the sow. Two two-trait animal m...

Data on 324 Holstein bulls from the July 1983 USDA Sire Summary and Holstein Association type evaluations were analyzed using multiple regression to determine which traits or combination of traits in a sire evaluation are most important in determining the price of a straw of semen. Over all bull studs, type was a major economic influence in determining price of semen. When bulls with outlier pr...

1 Estimates of variances due to differential expression of paternally and maternally 2 derived genes can be obtained from animal model type analyses by fitting appropriate 3 gametic effects. This is feasible for large scale analyses, as the inverse of the gametic 4 relationship matrix can be set up directly from a list of pedigrees. 5 We present a series of analyses applying such model for larg...

Group effects are used in sire evaluation models to account for genetic trend. The objective of this paper was to develop definitions of these group effects where sires are related. Definitions were obtained for sire groups from results of a set of modified mixed model equations. Definitions were functions of genetic selection differentials. Definitions were dependent on the matrix of numerator...

A total of 360 Iberian dam×Duroc sire pigs was used to study the influence of gender and castration of females (CM, castrated males; CF, castrated females; IF, intact females) and slaughter weight (SW; 145 and 156kg body weight, BW) on performance and carcass and meat quality. Each treatment was replicated four times (15 pigs). Intact females ate less, tended to have better feed conversion and ...

The effects of Spirulina supplementation, sire breed, sex and basal diet on intramuscular fat percentage (IMF) and fat melting point (FMP) in crossbred and purebred Merino lambs were investigated. Over two consecutive years, a total of 48 lambs was randomly allocated into feeding trials that utilised either ryegrass or Lucerne hay basal diets. Each treatment group had 8 lambs balanced by sire b...