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Showing 1 to 5 of 5 for “"herd-life"”.
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Relationships between first lactation milk yield, first calving interval, herd life, lifetime milk production, and descriptive type subtraits in Holstein cattle
… lactation production, first calving interval, herd life, and lifetime milk and fat yields. Variables other than type traits were expressed as deviations from the contemporary average. Heritabilities of type subtraits ranged from .00 to .45. First lactation milk and fat yields were approximately …
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Comparisons of Holstein, Brown Swiss, and Jersey cows for age at first calving, first calving interval, and true herd-life up to five years in seven regions of the United States
… calving in Holsteins, depending on the type of herd they were located in. Longer calving intervals might have been partly due to voluntary waiting period to breed the cows. The survival-related traits were evaluated up to five years of age. They consisted of stayability, number of completed …
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Relationships among estimated net income, herdlife and linear type traits in dairy cattle
… were developed for RNI and days of productive life (DPL) so that OC could be estimated from cows with shorter herd life opportunities. Within-herd correlations of RNI estimated from 84 month herdlife opportunity with that predicted from cows still alive at 36, 48, 60 and 72 months were .46, …
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Impact of sire PTA<SUB>SCS</SUB> on mastitis resistance and measures of daughter performance
… Holsteins obtained from the Virginia Tech herd and from VA DHI herds. Overall correlation of PTA<SUB>SCS</SUB> to lactation average SCS ranged from 0.13 to 0.17 across all data sets. Correlations between PTA<SUB>SCS</SUB> and 1st lactation SCS measures were higher than those between …
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Reasons Why Cows Were Removed From the SDSU Fairy Herd 1. Discriminant Analysis to Classify Cows with or without Reproductive Problems
… business is the ability of management to detect herd problems and correct them instead of culling cows. It is well known that the average productive life of the dairy cow is less than 4 yr, which is short compared with her potential life. Involuntary removal of cows causes economic loss directly …