The objective was to investigate measures of cellular innate immune responses among calm and temperamental Brahman bulls in response to handling and transportation. Sixteen Brahman bulls (344±37d of age; 271.6±45.5kg BW) classified as either calm (n=8) or temperamental (n=8) were loaded onto a trailer, transported for 4h to a novel facility, rested 16h overnight, and then were returned to their original facility after a 4h transport. Blood samples were collected immediately prior to (time 0) and at 24, 48, and 96h after initial loading for analyses of innate immune and blood parameters. Leukocyte counts did not differ (P>0.05) due to temperament before or after transportation, but neutrophil:mononuclear cell ratios were greater in temperamental bulls compared to calm bulls at 24h. At 24h, expression of peripheral neutrophil β 2-integrin decreased among all bulls compared with 0h (P<0.01). Temperamental bulls had greater glucose and cortisol than calm bulls (P<0.01) at 48h; whereas calm bulls had elevated neutrophil l-selectin expression, and phagocytic and oxidative burst activity compared with temperamental bulls (P<0.10) at 48h. The supernatant collected from endotoxin-stimulated whole blood cultures had greater TNF-α concentrations at 48h than at the other time points (P<0.05), but no temperament effect was observed (P>0.05). In contrast, 96h after initial loading the supernatant TNF-α concentrations were lower (P<0.05) among all cattle. Lastly, transportation increased neutrophil phagocytosis, oxidative burst, and cell adhesion molecule expression 96h post-transportation and the effect was more pronounced among calm bulls. These data suggest that neutrophils from calm bulls are more likely to resist microbial invasion at 96h after transportation than neutrophils from temperamental bulls.
- Immune response