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For 17 microsatellite markers, allele frequencies were determined in nine highly selected commercial broiler and six highly selected commercial layer lines using pooled blood samples from 60 animals. The average number of marker alleles was 5.8 over all lines, 5.2 over broiler lines, and 3.0 over layer lines. The average number of marker alleles within a(More)
The objectives of this study were to derive economic values in broiler breeding and to determine their relationship with production circumstances. Economic values were derived using a deterministic economic model based on profit equations with a fixed amount of broiler meat output of the production system. Nonintegrated and the integrated broiler production(More)
Estimates of heritabilities and genetic correlations for calving ease over parities were obtained for the Italian Piedmontese population using animal models. Field data were calving records of 50,721 first- and 44,148 second-parity females and 142,869 records of 38,213 cows of second or later parity. Calving ability was scored in five categories and(More)
QTL mapping experiments involve many animals to be genotyped and performance tested. Consequently, experimental designs need to be optimized to minimize the costs of data collection and genotyping. The present study has analyzed the power and efficiency of experiments with two or three-generation family structures containing full-sib families, half-sib(More)
Field records from 14,380 Japanese Brown steers by 92 sires were used to estimate genetic parameters for growth and carcass traits. Multipletrait restricted maximum likelihood (REML) procedures accounting for relationships among sires were used in estimating (co)variance components among average daily gain during fattening periods (ADG), carcass weight(More)
Variance components and breeding values for protein yield were estimated with REML without and with correction for heterogeneity of variances. Three different sire models were applied, which all accounted for genotype x environment (G x E) interaction. The first model included a sire x herd-year-season subclass (HYS) interaction. The second model divided(More)
Genetic correlations between longevity and conformation traits were estimated using data on Dutch Black and White cows born in 1978 (11,558 records), 1982 (39,252 records), and 1989 plus 1990 (58,864 records). Longevity traits considered were number of lactations, herd life, and stayabilities until 36 and 48 mo of age and their functional equivalents (i.e.,(More)
The objective was to present 2 methods for the derivation of nonmarket values for functional traits in dairy cattle using deterministic simulation and selection index theory. A nonmarket value can be a value representing animal welfare and societal influences for animal production, which can be added to market economic values in the breeding goal to define(More)
Longevity is an increasingly important trait in beef cattle. Increased longevity decreases costs for the farmer and increases revenue. The objective of this research was to investigate the phenotypic relationship between type traits and longevity in Chianina beef cattle, and the relationship between production and longevity, to analyze the effect of(More)
SUMMARY Inbreeding depression was estimated for four experimental Tribolium castaneum lines. Each line, containing approximately 7000 animals, was selected for 16 generations either randomly (control), on pupae weight (PWT), on family size (FST) or on an index containing both PWT and FST. The inbreeding trend was 0.9, 0.5, 0.5 and 0.4 % inbreeding per(More)