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Genetic trends of absolute and
relative heart
weight in a male broiler line
L.G. Gaya1, A.M.M.A. Costa2,
J.B.S. Ferraz2, F.M. Rezende2, E.C. Mattos2,
J.P. Eler2,
T. Michelan Filho3, G.B. Mourão4
and L.G.G. Figueiredo2
1Departamento de Produção
Animal, Centro de Educação Superior do Oeste,
Universidade do Estado de Santa Catarina, Chapecó, SC,
Brasil
2Grupo de Melhoramento Animal, Faculdade de Zootecnia
e
Engenharia de Alimentos da Universidade de São Paulo,
Pirassununga, SP, Brasil
3Aviagen do Brasil Ltda., Rio Claro, SP, Brasil
4Escola Superior de Agricultura Luiz de Queiroz,
Universidade de São Paulo,
Piracicaba, SP, Brasil
Corresponding author: L.G. Gaya
E-mail: lggaya@yahoo.com.br
Genet. Mol. Res. 6 (4): 1091-1096 (2007)
Received August 20, 2007
Accepted November 10, 2007
Published December 4, 2007
ABSTRACT. Data of chickens from a broiler-breeding
program have been collected and used for determination of genetic
trends of absolute and relative heart weight. The genetic trends
have been estimated by regression of the genetic values of the
traits over hatch-year. Genetic values of 42,912 individuals,
obtained by restricted maximum likelihood, were used for regression
analysis. The estimates of the genetic trends for absolute and
relative heart weight were found to be -0.08 g and -0.004%
per hatch-year, respectively. These trends show that heart weight
in the line analyzed, in absolute and relative terms, has tended
to decrease, which can make the metabolic disorders due to the
reduction in heart weight in broilers even worse.
Key words: Animal breeding, Ascitic
syndrome, Genetic value, Sudden death syndrome
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