Meishan synthetic sows and gilts have been shown to produce higher litter weights at weaning than White breed type sows and gilts (Sinclair et al. 1995). The explanation for increased litter weight weaned could be attributed to one of three areas: (1) The M sows are inherently better mothers than W and can support a higher level of piglet production. (2) The higher piglet production could be solely a result of hybrid vigour in the cross-bred piglets. (3) The increased litter production could be primarily attributed to a higher number of piglets born and reared by M. This experiment aimed to evaluate the maternal post-natal effects by standardising litters between breeds by cross-fostering techniques.

Sixty-four 3rd parity sows were used in a 2x2x2 factorial experiment to assess the influence of maternal breed type (Meishan synthetic 50% [M] or pure-bred European Landrace and Large White [W]), litter size (8 [L] or 12 [H] piglets) and breed of piglet (25% Meishan hybrid [m] or white hybrid [w]) on sow and litter production over a 28 day lactation. All litters were formed by cross-fostering 24hrs after farrowing.