Selection Practices and Genetic and Phenotypic Trends Estimated from Nebraska SPF Swine Field Records
نویسندگان
چکیده
منابع مشابه
Selection practices and genetic and phenotypic trends estimated from Nebraska SPF swine field records.
Records collected during 1971 through 1979 from 101,606 pigs raised in 18 herds that were members of the Nebraska SPF Swine Accrediting Association were evaluated for phenotypic trends and predicted and observed genetic trends. Traits considered were backfat at 100 kg (BF) and weight at 140 d of age (WT). Phenotypic change on average was beneficial for BF (-.05 mm/yr) but undesirable for WT (-....
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Records collected during 1971 through 1979 from 101,606 hogs raised in 18 Nebraska Specific Pathogen Free herds were analyzed. Traits considered were backfat at 100 kg (BF), weight at 140 d of age (WT) and, in some analyses, number of live pigs/litter at birth (NBA). The phenotypic correlation of BF and WT, averaged across herds, was -.07. The correlations between BF and NBA and between WT and ...
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ژورنال
عنوان ژورنال: Journal of Animal Science
سال: 1985
ISSN: 0021-8812,1525-3163
DOI: 10.2527/jas1985.6161411x