Behaviour of cattle: molecular biological background and relationship to milk performance

In a genome-wide association study 41 markers were identified for behaviour traits and BTA29 emerged to be an interesting genomic target region. Mutual markers for agitated behaviour and milk production showed competitive genotype effects. Gene expression profiles of the adrenal cortex revealed differentially expressed genes between cows with distinct temperament types. “Fearful/neophobic-alert” cows could be clearly discriminated from others by transcripts involved in the physiological stress response. Moreover, cows that were more fearful had lower milk yields in comparison to the others