Comparison of Three-Breed and Backcross Swine for Litter Productivity and Postweaning Performance

Abstract

SummaryDuroc, Hampshire and Yorkshire boars were mated with crossbred gilts of Duroc-Hampshire, Duroc-Yorkshire and Hampshire-Yorkshire breeding to produce 133 three-breed and 259 backcross litters that were farrowed during four seasons beginning in the fall of 1975. Threebreed cross litters were .31 -+ .27, .57 + .24 and .50 + .24 pigs larger than backcross litters at birth, 21 and 42 days, respectively, and .6 -+ .34, 2.3 -+ 1.2 and 5.4 + 2.4 kg heavier at these ages. The differences in average pig weight and survival percentage were small. Three-breed cross litters gained faster (.024 +-.007 kg/day) and were younger (-4.7 -+ 1.5 days) at 100 kilograms. Three-breed cross pigs were about 3% more efficient than backcross pigs. The differences in average backfat probe and average daily feed intake were small and not significant. Breed of sire contrasts for litter traits were small and not significant. However, significant differences between sire breeds existed for postweaning performance. Also, few differences between crossbred dam groups were significant for litter size or litter weight, but significant differences in postweaning perform-_ ance existed between progeny of crossbred dam groups. In general, pigs with Duroc breeding had the fastest growth rate and those with Hampshire breeding were the leanest.

Adjustment of 21-Day Litter Weight for Number of Pigs Nursed for Purebred and Crossbred Dams

“…(1978) and Wilson and Johnson (1980). Litters in this data set were farrowed in either the spring or fall from 1971 through the spring of 1977, except during the spring of 1974.…”

Evaluation of Three Candidate Genes Affecting Fatty Acid Composition in Pigs

“…Duroc breed has a high amount of marbling and has more a rapid growth rate than the Hampshire and the Yorkshire breed (Lowe et al, 2011;Wilson and Johnson, 1981). The high heritability (0.44) of lean growth rate in Duroc population indicated the lean growth rate can be improved by selecting animals having leanness and growth rate in the selection criteria (Chen et al, 2002).…”

National Pork Producers Council Maternal Line Genetic Evaluation: A comparison of growth and carcass traits in terminal progeny1

“…Much research was done in the 1970s and 1980s comparing breeds of pigs for reproduction, growth, and carcass traits (Wilson and Johnson, 1981;Kuhlers et al, 1 Funding for the project was provided through check-off dollars of the National Pork Board and administered by the National Pork Producers Council. …”