Estimation of heritability coefficients of number of born alive piglets in the first three farrowings swedish landrace sows

Abstract

The main objective of this study was to evaluate phenotypic and genetic variation of the number of piglets born alive (NBA) Swedish Landrace sows (SL) in three consecutive parities under the influence of sires, year and season of mating. The study included: 618 litters in the first, 470 in the second and 403 litter in the third farrowing. Testing the homogeneity of variance was performed with Levene's test. The data were analyzed using analysis of variance (Statistica Ver. 6.0., 2003). Heritability coefficients were evaluated by intra-class correlation. Swedish Landrace sires have influenced on the variability of the NBA's daughter in the first and second farrowing (p<0.05), but not in the third farrowing. Year and season of mating was not influenced on the variability of the NBA (p>0.05). The estimated heritability coefficients for the NBA were the highest in the second (0.123), then the first (0.092) and lowest in the third farrowing (0.030).

The Outcomes of Selection in a Closed Herd on a Farm in Operation

“…Most reproductive traits are lowly heritable since environmental and other factors have significant effects on the traits ( Imboonta et al, 2007 ). However, the heritability of NBA was high relative to previous studies ( Chen et al, 2003 ; Johnson and Nugent, 2008 ; Savić et al, 2011 ). These findings indicated that the records from the same herd reduced environmental and erroneous effects, which resulted in high heritability in reproductive traits in the present study.…”