Project Number: 1265-31000-085-11
Project Type: Specific C/A

Start Date: Aug 01, 2003
End Date: Dec 31, 2005

Objective:
The purpose of this project is to measure the effect of heat stress on reproductive performance, yield and somatic cell traits, and survival for cows of different breeds located in the same herd but in different regions of the United States.

Approach:
Herds that contain both Holstein and Jersey cows or both Holstein and Brown Swiss cows will be identified. Test day records of milk, fat, protein, and somatic cell score for cows freshening between January 1995 and June 2001 will be obtained from AIPL for these herds. Appropriate statistical models will be developed and used to measure breed differences in response to heat stress. Traits to be studied include reproduction (days open, calving interval), production traits and functions of test day information such as days to or duration of peak yield, and survival to deliver another calf. An important objective will be to measure breed differences in response to heat stress for herds located in different regions of the United States.

Project Team

Norman, H - Duane Bennet Cassell - Professor And Extension Dairy Scientist 301-504-8334

Related National Programs

Food Animal Production (101)