Skip to main content
ARS Home » Plains Area » Lubbock, Texas » Cropping Systems Research Laboratory » Livestock Issues Research » Research » Publications at this Location » Publication #233273

Title: The influence of temperament on endocrine, rectal temperature, and behavioral responses to an endotoxin challenge in bulls

item Burdick, Nicole
item Hulbert, Lindsey
item Caldwell, Lisa
item Loyd, Andrea
item Dailey, Jeffery - Jeff
item Vann, Rhonda
item Willard, Scott
item Carroll, Jeffery - Jeff Carroll
item Randel, Ron
item Welsh Jr, Tom

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 11/7/2008
Publication Date: 11/7/2008
Citation: Burdick, N., Hulbert, L.E., Caldwell, L., Loyd, A., Dailey, J.W., Vann, R., Willard, S., Carroll, J.A., Randel, R., Welsh Jr, T. 2008. The influence of temperament on endocrine, rectal temperature, and behavioral responses to an endotoxin challenge in bulls [abstract]. 6th Annual Pathways to the Doctorate Symposium, November 7-8, 2008, Commerce, TX

Interpretive Summary:

Technical Abstract: The host's complex reaction to pathogenic stressors involves interactions among the neural, endocrine, and immune systems. For example, exposure to bacteria stimulates secretion of the stress-related hormones, cortisol, and epinephrine. Basal and induced secretions of cortisol and epinephrine are influenced by temperament as more temperamental cattle exhibit higher basal concentrations of cortisol and epinephrine relative to calm cattle (Curley et al., 2006). Therefore, we hypothesize that temperament influences the stress hormone response to an endotoxin (lipopolysaccharide; LPS) challenge. This study was designed to determine the influence of temperament on LPS-induced changes in rectal temperature, sickness behavior, and the secretion of cortisol and epinephrine. Purebred Brahman bulls were selected from a pool of 60 bulls based on temperament score measured at weaning (n=8 each: Calm, Intermediate, and Temperamental). Bulls were fitted with rectal temperature devices and indwelling jugular catheters. Blood samples were collected every 30 minutes beginning 2 hours before and for 8 hours after LPS administration (0.5 microgram/kg) for determination of cortisol and epinephrine concentrations. At similar time points (-0.5 to 6 hours), sickness behaviors were assigned on a scale of 1 (lying on side with labored breathing) to 5 (active). Calm bulls displayed more signs of sickness following LPS than did Temperamental bulls (P<0.05). Temperamental bulls had greater cortisol and epinephrine concentrations prior to LPS administration (P<0.05). Cortisol concentrations increased in all bulls following LPS administration (P<0.05). Epinephrine concentrations increased (P<0.05) in Calm and Intermediate bulls in response to LPS (P<0.05); but not in Temperamental bulls (P>0.10). These data suggest that temperament affects the degree of response to an endotoxin challenge with Calm bulls having a greater adrenal medullary and behavioral response to LPS than Temperamental bulls. The differential response to LPS in Calm versus Temperamental bulls may result from Temperamental bulls having greater basal concentrations of cortisol and epinephrine.