Published online by Cambridge University Press: 02 September 2010
The study included 1013 gilts representing 28 one-way crosses among Yorkshire (Y), Landrace (Ld), Lacombe (Lc), Hampshire (H), Duroc (D), Berkshire (B), Large Black (LB) and Tamworth (T) breeds of swine. The crosses were distributed among five cooperating stations and were mated to Poland China boars to evaluate sow reproductivity based on the performance of the first two litters. The traits studied were weight at 112 days of age, age at puberty, percentage farrowing, litter size and weight at farrowing and at 3 weeks. Significant differences between crosses were found for all traits except farrowing percentage. The most prolific crosses were LdxY, HxLd and D x Y which gave birth to 11·0, 11·0 and 10·8 pigs per litter respectively, compared to the overall mean of 9·7 Ld x Y, LB x Lc and H x Ld crosses weaned litters 7·4, 5·3 and 4·9 kg heavier than the 40·5 kg mean for all crosses. Using percentage farrowing multiplied by litter 3-week-weight for the two litters as a measure of sow productivity, Ld x Y and LB x Lc crosses ranked highest. The breeds that had the best combining abilities for 3-week litter weight were Ld, Y, LB and Lc, however their specific combining abilities are important and hence not all crosses between these breeds produced superior performing crossbred sows. Overall, the Ld x Y was the most precocious, farrowed and weaned the greatest number of pigs per litter and had the heaviest litters at 3 weeks post-farrowing.