Beef cattle body temperature during climatic stress: a genome-wide association study

Authors

Jeremy T. Howard, University of Nebraska-LincolnFollow
Stephen D. Kachman, University of Nebraska-LincolnFollow
Warren M. Snelling, U.S. Meat Animal Research Center, USDAFollow
E. John Pollak, U.S. Meat Animal Research Center, USDAFollow
Daniel C. Ciobanu, University of Nebraska-LincolnFollow
Larry A. Kuehn, U.S. Meat Animal Research Center, USDAFollow
Matthew L. Spangler, University of Nebraska-LincolnFollow

ORCID IDs

Stephen D. Kachman

Date of this Version

12-22-2013

Citation

International Journal of Biometeorology 58 (2014), pp. 1665-1672; doi: 10.1007/s00484-013-0773-5

Comments

Copyright © 2013 ISB

Abstract

Cattle are reared in diverse environments and collecting phenotypic body temperature (BT) measurements to characterize BT variation across diverse environments is difficult and expensive. To better understand the genetic basis of BT regulation, a genome-wide association study was conducted utilizing crossbred steers and heifers totaling 239 animals of unknown pedigree and breed fraction. During predicted extreme heat and cold stress events, hourly tympanic and vaginal BT devices were placed in steers and heifers, respect i v e l y. I n d i v i dua l s we r e genotyped with t h e BovineSNP50K_v2 assay and data analyzed using Bayesian models for area under the curve (AUC), a measure of BTover time, using hourly BT observations summed across 5-days (AUC summer 5-day (AUCS5D) and AUC winter 5-day (AUCW5D)). Posterior heritability estimates were moderate to high and were estimated to be 0.68 and 0.21 for AUCS5D and AUCW5D, respectively.Moderately positive correlations between direct genomic values for AUCS5D and AUCW5D (0.40) were found, although a small percentage of the top 5 % 1-Mb windows were in common. Different sets of genes were associated with BT during winter and summer, thus simultaneous selection for animals tolerant to both heat and cold appears possible.