What question did this study set out to answer?

To estimate the genetic parameters and rates of improvement in milk and butterfat production achievable through progeny testing in dairy cattle.

January 1, 1960Journal of Dairy ScienceOpen Access

Rates of Improvement by Progeny Testing in Dairy Herds of Various Sizes

View Full Paper

Ask AI

Bookmark

Authors

LSL.W. Specht LGL.D. Mc Gilliard

Discussion

Member takes

Overview

Observational analysis demonstrates inheritance parameters and production metrics in dairy cattle, highlighting opportunities for genetic gain through progeny testing.

Key Points

To estimate the genetic parameters and rates of improvement in milk and butterfat production achievable through progeny testing in dairy cattle.
Analyzed Dairy Herd Improvement Association (DHIA) production records from 34,073 Holstein cows, including 5,098 artificial insemination (AI) daughters from 187 bulls.
Calculated repeatability, heritabilities based on paternal sister correlations, regression values for future AI progeny, and herd survival characteristics.
DHIA cows averaged 12,237 lb of milk and 435 lb of fat, while AI daughters averaged 12,305 lb of milk and 444 lb of fat.
Repeatability was 0.46 for milk and 0.40 for fat, with heritability estimates from AI paternal sister correlations reaching 0.31 for milk and 0.23 for fat.
Prediction regressions for future daughters were n/(n + 12) for milk and n/(n + 16) for fat, with cows culled at an annual rate of 26.3% and 70% of female calves entering production.

Cite This Study

Specht et al. (1960) studied this question.

synapsesocial.com/papers/6a88f56535a0dbe467a29ca6 https://doi.org/10.3168/jds.s0022-0302(60)90112-0

View Full Paper

Ask AI

Bookmark

January 1, 1960Journal of Dairy ScienceOpen Access

Rates of Improvement by Progeny Testing in Dairy Herds of Various Sizes

View Full Paper

Ask AI

Bookmark

Authors

LSL.W. Specht LGL.D. Mc Gilliard

Discussion

Member takes

Overview

Observational analysis demonstrates inheritance parameters and production metrics in dairy cattle, highlighting opportunities for genetic gain through progeny testing.

Key Points

To estimate the genetic parameters and rates of improvement in milk and butterfat production achievable through progeny testing in dairy cattle.
Analyzed Dairy Herd Improvement Association (DHIA) production records from 34,073 Holstein cows, including 5,098 artificial insemination (AI) daughters from 187 bulls.
Calculated repeatability, heritabilities based on paternal sister correlations, regression values for future AI progeny, and herd survival characteristics.
DHIA cows averaged 12,237 lb of milk and 435 lb of fat, while AI daughters averaged 12,305 lb of milk and 444 lb of fat.
Repeatability was 0.46 for milk and 0.40 for fat, with heritability estimates from AI paternal sister correlations reaching 0.31 for milk and 0.23 for fat.
Prediction regressions for future daughters were n/(n + 12) for milk and n/(n + 16) for fat, with cows culled at an annual rate of 26.3% and 70% of female calves entering production.

Cite This Study

Specht et al. (1960) studied this question.

synapsesocial.com/papers/6a88f56535a0dbe467a29ca6 https://doi.org/10.3168/jds.s0022-0302(60)90112-0

Also Consider

Synapse has enriched 4 closely related papers on similar clinical questions. Consider them for comparative context:

View Full Paper

Ask AI

Bookmark