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The efficiency of using more than one record as the selection criteria for litter traits in pigs

Frank Siewerdt^I; Ricardo A. Cardellino^II

^IDepartamento de Matemática, Estatística e Computação, Universidade Federal de Pelotas, 96010-900 Pelotas, RS, Brasil. Send correspondence to F.S.
^IIDepartamento de Zootecnia, Universidade Federal de Pelotas, Pelotas, RS, Brasil

ABSTRACT

Repeatability estimates for litter size and weight, at birth and at day 21, are reported for three breeds of pigs. The estimates ranged from 0.122 to 0.185, averaging 0.149. The repeatabilities were used to maximize the genetic progress in litter traits per time unit, and a rough prediction of genetic progress in the sampled populations was provided. It was concluded that data from the first two litters should be used to obtain the maximum possible amount of genetic progress.

Keywords: litter traits; pigs.

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