Design and standards for genetic evaluation of swine seedstock populations

Ways to improve the gene pool of pigs of the Russian Federation

An analysis of the system of breeding work in the pig industry of our country has been carried out. The scientifc and organizational factors that determine the improvement of breed and productive qualities of pigs have been analyzed. On the basis of many years of experimental data, selection practices obtained in the process of creating new breeding achievements, and using the scientifc results of the world science on genetics and animal breeding, proposals have been developed for a new system for assessing and improving the genetic potential of animal productivity based on modern achievements in genetics. In particular, a critical analysis was performed on the existing instructions for boning pigs, linear breeding, which does not meet the criteria of reality in the systematization of biological objects. The positive effect of breeding pigs in a closed mode in the form of a “line-population”, using such genetic markers as erythrocyte antigens, erythrocyte enzymes, lipoproteins, allowing intensifcation of the selection process, has been experimentally proved. When hogging pigs and developing breeding plans with a herd, it was proposed to use such selection and genetic parameters as heritability factors, phenotypic and genetic correlations, selective differential, selective effect, etc. for assessment of animals and prognostication of productivity. A system of continuous scoring of each selectable feature was developed, in contrast to the interval to the classes used in our country at the present time. A model of the selection index, taking into account the selection and economic signifcance of each of its components, has been proposed. Theoretical paths have been shown towards and experimental proof given to a relatively rapid transformation of breeds of animals bred in Russia to world-class productivity, as opposed to the constant import of breeding animals.

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

The objective of this study was to compare growth and carcass traits of 1,252 progeny of six commercially available dam lines included in the National Pork Producers Council Maternal Line Evaluation Project. Lines compared included one maternal line supplied by each of American Diamond Swine Genetics (ADSG), Danbred NA (DB), two lines supplied by Monsanto Choice Genetics (DK and GPK347), Newsham Hybrids (NH), and Landrace x Large White females supplied by the National Swine Registry (NSR). All females were mated to DB, Duroc-Hampshire terminal sires. Traits analyzed were ADG from 56 to 115 kg live weight, days to 115 kg, backfat thickness measured at the 10th rib, carcass length, dressing percent, and 10th-rib LM area. Carcass traits were adjusted to a carcass weight of 85 kg. The statistical model included fixed effects of maternal line, sex, farrowing group, and finishing unit (farm). All two-way interactions among main effects were tested and removed from final models because they were not significant. In addition, because they were not significant, effects of farm and farrowing group were removed from models for carcass length and 10th-rib backfat thickness, and farm was removed from the model for LM area. Least squares means for ADG ranged from 0.74 to 0.79 kg/d. The GPK347 line had lower ADG and greater days to 115 kg than all other lines (P < 0.05). The ADSG (P < 0.05) and NH (P < 0.01) progeny had lower ADG than DK progeny. The DK line had the fewest days to 115 kg (P < 0.05). Progeny for the DB and NH lines had the least 10th-rib backfat, differing from ADSG, DK, and GPK347 (P < 0.05). Pigs from DB females had the greatest dressing percent, differing from ADSG, DK, GPK347, and NH (P < 0.05). The GPK347 had a lower dressing percent than all other lines (P < 0.05). Progeny of DB females had the greatest LM area, differing from ADSG, DK, GPK347, and NSR (P < 0.05). Offspring from ADSG and GPK347 had the smallest LM area; however, GPK347 and NSR did not differ. Differences in carcass length were statistically significant; however, actual differences were small. Economic weights for these traits relative to reproductive traits must be considered in integrated economic analyses to properly compare differences among lines in net economic value for specific markets.