Discipline: Agribusiness, Animal Science
This study aimed to evaluate and compare the reproductive performance of market hogs and the Landrace x Large White (F1) crossbreds. A total of 202 sows composed of 101 market hogs converted to breeders (MHB) and 101 Landrace x Large White (F1) crossbreds were used in this study. The market hogs were progenies of the Landrace x Large White (F1) crossbred parental stocks (PS) and the synthetic hybrid sire. They were raised in growing-finishing pens, selected and considered as replacement gilts when they reached 4.5 months of age. Their selection was based on body size, body conformation and number of teats (at least six pairs of equally spaced teats). At 5 months old, all gilts were subjected to the standard management for the replacement gilts and later, for the sows. The gilts were bred when they reached 7.5 months old. MHB and PS were bred to either hybrid sire or GP sire but mostly to the former. Litter size at birth of the two genetic groups (Landrace x Large White Crossbred and Market Hog Breeder) did not differ. The Landrace x Large White (F1) crossbred group was larger (p<0.05) litter size at birth by 0.41 kg over the other group. Litter size at birth and litter size at weaning were significantly in favor of parity 2. Genetic group within parity 1 and within parity 2 did not significantly affect litter size at birth. In each genetic group, litter size at birth increased from parity 1 to parity 2. Genetic group within parity 1 significantly affected litter size at weaning but not within parity 2. At weaning, litter size in each genetic group increased from parity 1 to parity 2. The genetic group of sows did not significantly affect the pig weight at birth, but it significantly affected the weaning weight of pig. At weaning, pigs of the FI crossbred had an advantage of 0.35 kg over the other group. Parity did not significantly influence pig weight at birth and at weaning. Genetic group within parity 1 and within parity 2 did not significantly influence pig weight at birth. However, birth weight of pigs born to F1 crossbred sow were higher in parity 2 than parity 1. Within parity 1 and parity 2, the genetic group significantly influenced pig weaning weight. For parity 1 and parity 2, weaning weights of pigs born to F1 crossbred were heavier than those of pigs born to the other group.