Francisco F. Peñalba | Severino S. Capitan | Renato S.A Vega | Beatriz R. Garcia | Arnel N. Del Barrio
Discipline: Veterinary Medicine, Animal Science
The first and second parity performance of Landrace (LD) x Large White (L W) crossbreds in backcrossing and four-breed crossbreeding were evaluated using 14 LD x L W females backcrossed to Landrace sire, 13 L W x LD females backcrossed to Large White sire and 20 mixture of LD x L Wand L W x LD bred to Duroc x Pietrain sire. Data gathered (litter size at birth and weaning, pig weight at birth and weaning, and pre-weaning mortality) were analyzed using an analysis of variance in a nested design with breed (sire), parity and parity within breed as the independent variables. Analysis of variance revealed that the effects of breed and parity within breed were not significant, while the effect of parity was significant (P<0.05) on pig weight at birth and weaning in favor of the second parity. The mean values for litter size at birth and weaning also favored the second parity. Data showed that backcrossing of Landrace x Large White crossbreds was comparable to four-breed crossbreeding with the same dam breeds mated to Duroc x Pietrain with the former system having a slight advantage in litter size at birth and weaning and pig weight at birth.