Arquivo Brasileiro de Medicina Veterinária e Zootecnia
On-line version ISSN 1678-4162
MARQUES, L.F.A. et al. Analyse of growth traits in Simmental breed in Brazil. Arq. Bras. Med. Vet. Zootec. [online]. 2000, vol.52, n.5, pp.527-533. ISSN 1678-4162. http://dx.doi.org/10.1590/S0102-09352000000500020.
Records of birth, 100-day, weaning, yearling and 550-day weights of 7,587 calves born from 1977 to 1997, and 25,812 pedigree data were used to estimate variance components and genetic parameters of Simmental cattle raised on farms in Brazil, with MTDFREML procedure under animal model. The estimates of total, direct and maternal heritabilities, genetic correlations between maternal and genetic effects, and maternal permanent effects obtained by bivariate analyses, were estimated combining the weaning weight (205 days) with the other weights, being respectively .23, .22, .05, -.10, .07 for birth weight; .09,.08, .00, .85, .17 for 100-day weight; .13, .13, .05, -.17, .02 for 205-day weight; and .15, .19, .06, -.41, .03 for 365-day weight. Direct heritability, estimated for 550-day weight, in two traits analysis with weaning weight, was .24. Except for birth weight (moderate), the genetic, phenotypic and environmental correlations between weaning weight and other traits were high and positive. The maternal effects were important for Simmental cattle and should be included in beef cattle breeding programs.
Keywords : Cattle; Simmental; growth traits; animal model; heritability; correlation.