Cattle temperament has been shown to influence cattle performance, and new research conducted at the University of Saskatchewan has examined the relationship among temperament and measures of stress and social interactions.
At the American Society of Animal Science-Canadian Society of Animal Science annual meeting in Austin, Texas, University of Saskatchewan graduate student Tess Mills said the temperament trait is unique to each animal and is capable of influencing the animal's response to handling. She noted that temperament is a stable trait that is influenced by many factors and is moderately heritable, which means there may be potential for genetic selection for cattle temperament.
She further explained that excitable cattle perceive handling as a major stressor and react more violently to that handling, which can create a greater risk of injury to themselves, other cattle or stock people.
Also, Mills said higher levels of cortisol in excitable animals leads to chronic stress, which leads to reduced immune function and increased susceptibility to disease.
Mills' co-authors were Diego Moya Fernandez with the Western College of Veterinary Medicine and Paisley Johnson with the University of Saskatchewan.
For the experiment, the researchers used 48 Hereford crossbred heifers to determine the relationship between different temperamental traits with blood parameters, levels of stress hormone and social interactions of beef cattle, Mills said.
According to Mills, animals exhibiting dominant behaviors had a greater level of plasma cortisol (P = 0.0435) and flight speed (P = 0.0371) than those with a balanced social status, while those with a balanced social status -- exhibiting both dominant and subordinate behaviors -- had a greater (P = 0.0115) white blood cell count than those heifers with a subordinate social profile.
Mills reported a strong positive correlation (P = 0.0094, R-square= 0.7386) between flight speed and plasma cortisol.
She concluded that there is a relationship between temperament, levels of stress hormones and social dominance, suggesting that temperament affects the amount of stress individual animals experience as well as their health and social status.