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Two groups of 10 Holstein cows were chosen by pairs from a 20-yr genetic selection project that used either breed average or breed high sires chosen only for Predicted Differences in milk production. Milk production (305-d mature equivalent) was 10,814 kg and 6912 kg for the high and average groups of cows. Days to first visual estrus and number of(More)
Breeding receipts from artificial insemination were matched with records of milk yield from northeastern United States. Nine measures of yield and 10 measures of fertility were investigated. A completely random model with herd-year-season, sire, and interaction of sire by herd-year-season was applied by parity; interaction of sire by herd-year-season was(More)
Measures of yield and fertility were obtained from breeding receipts of artificial insemination and records of test-day yield. Estimates of heritability were by Henderson Method 3, maximum likelihood, and restricted maximum likelihood. Heritabilities for measures of yield varied, but most were within the range of earlier estimates. Measures of fertility had(More)
Influences of days open present lactation, days open previous lactation, and days dry previous lactation were fit simultaneously to determine their effects on measures of yield, which were fat-corrected milk, milk, and milk fat, all adjusted to a 305-d mature equivalent basis. Best linear unbiased estimates were obtained. Multiparity analyses were conducted(More)
New statistical procedures for analysis of ordered categorical data were investigated. In using the standardized threshold model, scores are transformed to estimate unknown boundary points and fixed and random effects on an underlying scale of continuous response. The model for calving ease included sex of calf, parity of dam, and the unknown boundary(More)
The inverse of the gametic covariance matrix between relatives, G(-1), for a marked quantitative trait locus (QTL) is required in best linear unbiased prediction (BLUP) of breeding values if marker data are available on a QTL. A rapid method for computing the inverse of a gametic relationship matrix for a marked QTL without building G itself is presented.(More)
Relationships between genetic measures of mastitis (somatic cell score, score for clinical mastitis, and scores for IMI with major or minor pathogens) and immunological parameters (physiological and molecular markers) were examined for periparturient Holstein cows. Physiological markers included 11 in vitro immunological assays. Molecular markers included(More)
First lactation milk, fat, protein, and lactose yields and percentage yields were analyzed using a multiple-trait sire model including herd-year-season, sire group, and age of cow as fixed effects. Somatic cell score was fit both as a fixed effect in the model and as an additional dependent variable in two analyses with almost identical results. Variance(More)
Genetic correlations between dystocia in first with later parities and between direct with maternal effects for dystocia were estimated. Dystocia in first and later parities represent similar traits because of a large genetic correlation of .84. This similarity should allow calving reports on older dams and heifers to be combined in predicting a bull's(More)
The associations between alleles at the BoLA (bovine lymphocyte antigen) DRB3 locus and 20 indicator traits of innate and adaptive immunity were investigated. Periparturient Holsteins (n = 127) were genotyped at the BoLA DRB3 locus using polymerase chain reaction and restriction fragment length polymorphism. Twenty-two alleles were observed in the study(More)