Author
SHARON, KATE - Texas Tech University | |
LIANG, YU - Texas Tech University | |
Sanchez, Nicole | |
Carroll, Jeffery - Jeff Carroll | |
BALLOU, MICHAEL - Texas Tech University |
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only Publication Acceptance Date: 12/3/2014 Publication Date: 2/1/2015 Citation: Sharon, K.P., Liang, Y.L., Sanchez, N.C., Carroll, J.A., Ballou, M.A. 2015. Plane of nutrition during the preweaned period influences the pathophysiological responses to a combined intranasal bovine herpesvirus-1 and intratracheal Mannheimia haemolytica challenge in post-weaned Holstein calves. Journal of Animal Science Supplement. 93 (E Supplement 1): 19-20 Abstract#47. Interpretive Summary: Technical Abstract: The objective was to determine whether previous plane of milk replacer nutrition (PON) influences the pathophysiological responses to a combined viral-bacterial respiratory challenge. Thirty Holstein calves (1 day of age) were assigned to treatments in a 2 x 3 factorial arrangement with preweaned PON and intratracheal dose of M. haemolytica as the main effects (n=5 treatment). Calves were fed either a low (LPN; n=15) or a high plane of nutrition (HPN; n=15) from birth through weaning. Two-thirds of the calves did not receive adequate colostrum, = 5.2 grams per deciliter total serum protein upon arrival. Calves fed the LPN were fed 445 grams dry mater per day of milk replacer until weaning, and the HPN calves were fed 830 grams dry mater per day of milk replacer during the first 10 days and 1080 grams from day 11 until weaning. Calf starter and water were offered ad libitum. Calves were step-down weaned at 54 days. Calves were moved into an enclosed barn at 70 days. Indwelling rectal temperature (RT) probes and jugular catheters were inserted at 80 days. All calves were challenged with 1.5 x10^8 plaque formng units per mililiter per nostril of bovine herpesvirus-1 (BHV-1) at 81 days. Calves were challenged with 10^6, 10^7, or 10^8 colony forming units of M. haemolytica at 84 days. Blood samples were collected every 6 hours after the BHV-1 challenge, then every 30-min from -2 to 8 hours, and 12, 18, 24, 36, 48, 96, 144, and 240 hours relative to the the M. haemolytica challenge. A linear, mixed model with the fixed effects of PON, M. haemolytica dose, time, and their interactions was fitted using the Mixed procedure of SAS. Body weights at 70 days were different (P=0.001) between LPN and HPN (62.2 vs. 81.2 +/- 2.67 kilograms, respectively). Although HPN consumed more calf starter (P=0.001) throughout the respiratory challenge, there were no differences (P>0.424) in ADG or when starter intake was expressed per kg BW^0.75. The neutrophil:lymphocyte ratio was greater (P=0.001) among LPN than HPN after the BHV-1 (1.14 vs. 0.66 +/- 0.084) and M. haemolytica (1.51 vs. 0.95 +/- 0.069) challenges. There was a PON x M. haemolytica interaction (P=0.001) on RT, whereas the 10^8 M. haemolytica dose caused the greatest rise in RT among HPN calves, but the lowest among LPN calves. These data demonstrate that calves previously fed a LPN had a more severe pathophysiological response to a combined viral-bacterial respiratory challenge. |