Skip to main content
ARS Home » Research » Publications at this Location » Publication #192147
Title: ISSUES IN GENETIC EVALUATION OF DAIRY CATTLE FOR HEAT TOLERANCE

Author
item MISZTAL, I - UNIV OF GA, ATHENS
item BOHMANOVA, J - UNIV OF GA, ATHENS
item FREITAS, S - UNIV OF GA, ATHENS
item TSURUTA, S - UNIV OF GA, ATHENS
item Norman, H
item LAWLOR, T - HOLSTEIN ASSOCIATION

Submitted to: World Congress of Genetics Applied in Livestock Production
Publication Type: Proceedings
Publication Acceptance Date: 5/6/2006
Publication Date: 8/13/2006
Citation: Misztal, I., Bohmanova, J., Freitas, S., Tsuruta, S., Norman, H.D., Lawlor, T.J. 2006. Issues in genetic evaluation of dairy cattle for heat tolerance. World Congress of Genetics Applied in Livestock Production. Communication 01-12.

Interpretive Summary: Several projects have been undertaken with the purpose of refining a genetic evaluation of Holstein for heat tolerance. It was found that the weather data from public weather stations may be as good or better as that collected on-farm. Also, test days capture less than one half of response to heat stress obtained with daily records. A test day model accounting for heat stress was used for the national evaluation in the U.S. Heat tolerant sires were lower on fluid milk and dairy form, neutral on TPI, and positive for fertility and productive life. G x E interaction due to heat stress can be quantified on the national scale.

Technical Abstract: Several projects have been undertaken with the purpose of refining a genetic evaluation of Holstein for heat tolerance. It was found that the weather data from public weather stations may be as good or better as that collected on-farm. Also, test days capture less than one half of response to heat stress obtained with daily records. A test day model accounting for heat stress was used for the national evaluation in the U.S. Heat tolerant sires were lower on fluid milk and dairy form, neutral on TPI, and positive for fertility and productive life. G x E interaction due to heat stress can be quantified on the national scale.