Parámetros genéticos y tendencias genéticas para características de comportamiento en ganaderías de lida mexicanas.

The aims of this study were to estimate variance components; calculate heritability (h²) and genetic correlations (rg) predict breeding values (VG) and evaluate their trends over time. Behavior information was analyzed for four Mexican bullfighting ranches: Los Encinos (ENC), Montecristo (MCR), San José (SJO) y Fernando de la Mora (FMO). The analyzed information included was horse tienta (TC), foot tienta (TP), horse bullfight (LC) and foot bullfight (LP). The number of observations ranged from 154 to 2,369, the number of animals in the pedigrees varied from 3,246 to 8,962. Multivariate analyses were conducted using the MTDFREML software. The estimates of h² were from medium to high magnitude, in a range from 0.09±0.05 to 0.47±0.22, and an average of 0.28±0.09. The average of h² by trait was 0.33±0.06 for TC and TP, 0.23±0.14 for LC and 0.27±0.12 for LP. All rg were positive and higher than 0.50, with the exception of TP and LP (0.44±0.38) in FMO, and TC and LP (0.28±0.14) in MCR. The average of the rg within ranches was 0.71±0.14 in MCR, 0.77±0.35 in FMO, 0.78±0.18 in ENC, and 0.85±0.31 in SJO. The trends of the VG were positive and nonzero (P<0.02), with the exception of LP in FMO (P>0.05). The magnitude of the genetic gain per year, as a percentage of the mean, ranged from 0.19% in LC of FMO to 1.5% in TP of ENC. The variability of VG suggests its use in breeding programs to promote greater genetic progress. [ABSTRACT FROM AUTHOR]