Data from the first four parities of Large White pigs were used to estimate (co)variance components and genetic parameters for litter size (LS) in single trait and multi-trait analyses. The (co)variance components and genetic parameters were estimated by restricted maximum likelihood using the MTDFREML program. LS in each parity was considered a different trait and the models included contemporary group as fixed effect and additive direct genetic and residual as random effects. Heritability estimates of LS in different parities in […]

The objectives of this study were to estimate heritabilities and genetic correlations for milk (MY), fat (FY) and protein (PY) yields and for percentages of fat (%F) and protein (%P) in milk of Holstein cows in Paraná State. Data consisted of 117,082 lactation records for MY, FY and PY and 116,747 records for %F and %P from herds supervised by the Milk Recording Service of the Holstein Breeders Association of Paraná from January 1992 to December 2003. Covariance components and […]

This study aimed to evaluate the genotype × environment interaction effect on birth (PN), weaning (P205) and yearling (P550) weights of Nellore cattle raised in 46 farms in three states (Rio Grande do Sul-RS, Santa Catarina-SC and Paraná-PR) of the South Region of Brazil, from 1976 to 2001. Records on 10,874 animals, sired by 425 bulls and 7,629 dams were used to estimate (co)variance components by REML. Univariate and bivariate models included the contemporaneous group, feeding type (P205 and P550), […]

The objective of this study was to estimate heritability of scrotal circumference at 12 months of age (SC12), age (AFC) and weight (WFC) at first calving and genetic correlations between each of these traits and the following growth traits: weight at birth (BW), weaning (WW), twelve (W12) and eighteen (W18) months of age, weight gain from birth to weaning (DGBW) and from birth to eighteen (DGB18) months of age, days to 175 kg from birth to weaning (D175 = 175/DGBW) […]

The objective of this study was to estimate heritability and genetic correlations for body weight at birth (BW), weaning (WW), twelve (W12) and eighteen (W18) months of age, weight gains from birth to weaning (DGBW) and from birth to eighteen months of age (DGB18), days to 175 kg from birth to weaning (D175 = 175/DGBW), days to 450 kg from birth to slaughter (D450 = 450/DGB18) and female mature body weight (ABW) using data from a herd of Canchim (5/8 […]

The objective of this study was to estimate the genetic and phenotypic relationships between somatic cell count (SCC) and milk yield and to evaluate the possibility of using SCC as a selection criteria in breeding programs of dairy cattle. Somatic cell count records were transformed into somatic cell score (SCS) using a logarithmic scale. Genetic parameters for milk yield (305 days) and average somatic cell score (ASCS) were estimated. The overall means for 305-day milk yield (MY305) and ASCS were, […]

The present study aimed to evaluate the effects of hair coat on age at first calving (IPP) and calving interval (IEP) of Holstein cows managed under free stall with fans and sprinklers and to estimate genetic and phenotypic parameters for these traits. Data were analyzed by the least-squares method using a model that included the effects of year; season; origin of sire; sire within origin; number of inseminations; age (only for calving interval); percentage of black meshes; hair coat thickness; […]

This study aimed to estimate genetic and phenotypic parameters for weight and height (4860 records) of equines from four genetic groups: Brazilian Showjumper (BH), Thoroughbred (PSI), Hanoverian (HAN) and No Defined Breed (SRD). Data collected from 1977 to 2002 on 1629 animals was provided by the Brazilian Army. Models used for analyses included the fixed effects of month and year of foaling and measuring, age of dam, foal sex and genetic group. Foaling month did not affect height or weight […]

The objective of this study was to evaluate the genotype × environment interaction for weaning and yearling weights, daily weight gain from weaning to 12 months of age and the growth performance in Canchim (5/8 Charolais + 3/8 Zebu) beef cattle estimated by a principal components analysis including those three traits. The environment was defined by season of birth (first and second semesters of the year). Genetic parameters were estimated by bayesian method with the Gibbs sampler using bivariate analyses […]

Records of growth traits of 1,698 animals born from 1979 to 2002 in a Caracu herd selected for yearling weight were used to estimate genetic parameters for birth weight (PN), weight at 4 months adjusted at 120 days (P120), weaning weight adjusted at 210 days (P210), daily weight gain from birth to weaning (GND), weight adjusted at 378 days of males (P378), weight adjusted at 550 days of heifers (P550), daily weight gain during the performance test (G112), post-weaning daily […]