Location: Livestock Issues ResearchTitle: Yeast supplementation reduced the immune and metabolic responses to a combined viral-bacterial respiratory disease challenge in feedlot heifers Author
|Word, Alyssa - Texas Tech University|
|Roberts, Shelby - Texas A&M University|
|Richeson, John - Texas A&M University|
|Defoor, Paul - Cactus Feeders, Inc|
|Cravey, Matt - Phileo Lesaffre Animal Care|
|Corley, Jimmie - Phileo Lesaffre Animal Care|
|Ballou, Micheal - Texas Tech University|
|Carroll, Jeffery - Jeff Carroll|
Submitted to: Proceeding of Plains Nutrition Council Symposium
Publication Type: Abstract Only
Publication Acceptance Date: 3/28/2016
Publication Date: 4/15/2016
Citation: Word, A.B., Broadway, P.R., Sanchez, N.C., Roberts, S.L., Richeson, J.T., Defoor, P.J., Cravey, M.D., Corley, J.R., Ballou, M.A., Carroll, J.A. 2016. Yeast supplementation reduced the immune and metabolic responses to a combined viral-bacterial respiratory disease challenge in feedlot heifers. Proceeding of Plains Nutrition Council Symposium. 2016 Plains Nutrition Council Spring Conference Proceedings 04/15-16/2016 San Antonio, TX: pg.125.
Technical Abstract: Two treatments were evaluated in commercial feedlot heifers to determine the effects of a yeast supplement on immune and metabolic responses to a combined viral-bacterial respiratory disease challenge. Thirty-two beef heifers (324 ± 19.2 kg BW) were selected and randomly assigned to one of two treatments and fed for 31 d: Control (CON), receiving no yeast supplement in the ration, or yeast (YEAST), control ration plus a combination live yeast (2.5 g'hd-1'd-1) and yeast cell wall (2.5 g'hd-1'd-1) supplement (Phileo-Lesaffre, Milwaukee, WI). On d -3 all cattle were challenged intra-nasally with 1x108 pfu BHV-1 and allowed to rest in outdoor pens for 3 d. On d 0, all cattle were challenged intra-tracheally with an average dose of 3 x107 cfu Mannheimia haemolytica, fitted with an indwelling jugular catheter and indwelling vaginal temperature recording device, and were moved into individual stanchions in an enclosed barn. Whole blood samples were collected at the time of BHV-1 challenge at 1-h (serum) or 2-h (complete blood cell counts) intervals from 0 to 8 h, and at 12, 24, 36, 48, 60, and 72 h relative to M. haemolytica challenge. Data were analyzed using the mixed procedure of SAS specific for repeated measures with fixed effects of treatment, time, and their interaction. There was no difference in cortisol concentration or vaginal temperature between treatments (P = 0.37). Although there was no treatment difference in total white blood cell count following BHV-1 challenge (P = 0.21), there was a tendency (P = 0.07) for cattle in the CON group to have greater neutrophils than YEAST. Serum haptoglobin concentration tended (P = 0.13) to be decreased in the YEAST group compared to CON. Cattle in the YEAST group had a greater serum glucose concentration relative to administration of the M. haemolytica challenge (P = 0.01) and decreased concentrations of serum urea nitrogen compared to CON (P = 0.03). There was no difference in serum NEFA concentration between YEAST and CON (P = 0.37). Nasal lesion score tended to be decreased in YEAST cattle compared to CON (2.5 vs. 3.19, P = 0.07). In summary, feeding a combination live yeast and cell wall yeast supplement tended to reduce the inflammatory response in beef heifers. Feeding the supplement also decreased the breakdown of metabolic substrates required to provide energy for the immune response to a respiratory disease challenge.