ARS | Publication request: The influence of temperament on transportation induced increases in body temperature and secretion of cortisol and epinephrine in bulls

Submitted to: Beef Cattle Research in Texas
Publication Type: Proceedings/Symposium
Publication Acceptance Date: September 1, 2008
Publication Date: N/A

Interpretive Summary: A collaborative study was conducted involving scientists from the Livestock Issues Research Unit, Mississippi State University, Texas A&M University, and the Texas AgriLife Research Center in Overton, TX, to determine if an animal's temperament would influence its response to transportation stress. For this study, 25 yearling Brahman bulls were transported 770 km from Overton, TX, to New Deal, TX. Rectal temperature was collected during transported utilizing an indwelling rectal probe developed within the Livestock Issues Research Unit. Blood samples were collected before and after transportation to evaluate concentrations of various stress hormones. Results from this study revealed that temperament was a clear indicator of the response of bulls to transportation. Temperamental bulls had greater concentrations of cortisol and epinephrine and also had greater body temperature when compared with calm bulls. This suggests that selecting for calmer bulls will prevent negative impacts of elevated body temperature due to transportation stressors. The results of this research will be of particular interest to beef cattle feedlot managers, veterinarians managing the health of feedlot cattle, and scientists, whether from industry, academia, or industry, working in the area of beef cattle production, health, and well-being.

Technical Abstract: This study was designed to determine the influence of temperament on rectal temperature (RT) and secretion of cortisol (CS) and epinephrine (E) in response to transportation. Purebred Brahman bulls were selected based on temperament score measured at weaning [n=8 each: Calm (C), Intermediate (I), and Temperamental (T)]. Bulls were fitted with rectal temperature devices and blood was collected pre- and post-transportation. Bulls were loaded onto a trailer and transported approximately 770km from Overton, TX, to New Deal, TX. Serum and plasma concentrations of cortisol and epinephrine, respectively, were determined. Prior to transportation (0 min) T bulls had greater RT. During transportation, RT peaked within 30 minutes, with T bulls having the greatest peak RT. The lowest RT was reached at 400 minutes (6.5 hr) of the onset of transportation, with C bulls having the lowest RT. Prior to transportation, T bulls had greater CS and EPI concentrations. This was similar at post-transportation CS. In summary, temperament was predictive of the changes in rectal temperature due to transportation.