Evaluation of the F1 and backcrosses of Nigerian local pigs and the Large White for litter characteristics in Southwest Nigeria
Livestock Research for Rural Development
Department of Animal Science, Faculty of Agriculture, Obafemi Awolowo University, Ile-Ife, Nigeria
A total of 823 farrowing records representing five genetic groups of pigs - Nigerian local pigs (NP), the Large White (LW), NPxLW, (NPxLW) xLW, and (NPxLW) xNP - were used to investigate the effect of pig genotype on litter performance under the humid tropical conditions of Southwestern Nigeria. Past data records spanning a period of 12 years (1979 - 1990) were collected from the Swine Unit of the University Research Farm, Ile-Ife, Nigeria. Data were analyzed using least squares procedures. Effects in the model included genetic group of litter, year and season of farrowing, and genetic group x season of farrowing interaction. Traits evaluated included litter sizes and weights at farrowing and at weaning, including pre-weaning viability. Results showed significant effect of genetic group for all the litter traits studied. The crossbred groups were superior in most of the litter traits studied except litter birth weight where the LW purebred group recorded the heaviest litter weights. Season of farrowing affected litter performance traits in LWxLW, NPxLW and (NPxLW)xLW groups. In terms of pre-weaning viability, litters from the (NPxLW) xLW had 13.8% and 8.0% greater liveability at 42 days than litters from purebred NP and LW respectively.
Pieris brassicae; Sus scrofa