Reproductive performance was recorded on purebred Large White, purebred Meishan and both reciprocal F1 females when mated to Large White and Meishan boars. Crossbreeding parameters were estimated in first parity litters by restricted maximum likelihood. The breed difference in number of piglets born alive (NBA) was largely controlled by maternal genes (acting in the dam of a litter), with the maternal breed difference estimated at 4.9+1.2 piglets in favour of the Meishan. However, there was a grandmaternal breed difference in favour of the Large White of 1.7+0.8 piglets and the estimated total breed difference was 3.2 piglets. Maternal heterosis for NBA was positive and high, and of similar magnitude to the maternal additive breed difference. The maternal breed difference in ovulation rate (OR) was 6.2+1.0 ova in favour of the Meishan, but there was a 2.0+0.7 grandmaternal effect in favour of the Large White. No significant heterosis for OR was found. Breed differences in prenatal survival (PS) were small, although significant positive maternal heterosis was observed. However, after adjustment for maternal differences in OR, maternal breed differences in PS were estimated at 21.1+7.2% in favour of the Meishan. In neither analysis was there any significant influence of the genotype of the embryo/foetus or of the granddam on PS. Analyses of NBA after adjustment for maternal differences in OR confirm that the prolificacy of the Meishan is largely a consequence of its high level of PS at a given OR and that this is largely controlled by genes acting in the dam of a litter.
Proceedings of the World Congress on Genetics Applied to Livestock Production, Volume XV. Beef cattle, sheep and pig genetics and breeding, fibre, fur and meat quality., , 458–461, 1990
|Download Full PDF||BibTEX Citation||Endnote Citation||Search the Proceedings|
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.