The impact of oral meloxicam prior to transportation on inflammatory mediators and immune function of arriving feedlot cattle

Authors: CAPIK, SARAH - Kansas State University; WHITE, BRAD - Kansas State University; LARSON, ROBERT - Kansas State University; VAN ENGEN, NICHOLAS - Iowa State University; CERNICCHIARO, NATALIA - Kansas State University; ENGELKEN, TERRY - Iowa State University; LAKRITZ, JEFF - The Ohio State University; BALLOU, MICHAEL - Texas Tech University; HULBERT, LINDSEY - Kansas State University; VANN, RHONDA - Mississippi State University; CASWELL, JEFF - University Of Guelph; JACOB, GABRIELLA - University Of Guelph; Carroll, Jeffery - Jeff Carroll; COETZEE, JOHANN - Iowa State University

Submitted to: American Journal of Veterinary Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/22/2017
Publication Date: 12/1/2017
Citation: Capik, S.F., White, B.J., Larson, R.L., Van Engen, N., Cernicchiaro, N., Engelken, T.J., Lakritz, J., Ballou, M.A., Hulbert, L.E., Vann, R., Caswell, J.L., Jacob, G., Carroll, J.A., Coetzee, J.F. 2017. The impact of oral meloxicam prior to transportation on inflammatory mediators and immune function of arriving feedlot cattle. American Journal of Veterinary Research. 78(12):1426-1436.

Interpretive Summary: Across the beef production system, cattle experience varied stressors throughout their lives including weaning, handling for basic processing or other procedures, commingling at auction markets or other facilities, and transportation between locations in the production system. Cattle are frequently transported multiple times within their lifetime for varying distances. Long-distance transportation is considered a significant source of stress in cattle and has been associated with increased bovine respiratory disease morbidity risk. This study represents a collaborative effort among scientists from several state, federal and international entities to investigate the effects of providing an anti-inflammatory drug, meloxicam, to cattle prior to shipping on the overall stress and immune response during and after a long-distance transportation event, and the subsequent growth performance in the feedlot. Overall, the results from this study do not support the use of meloxicam as a means of mediating the effects of transport stress in single-source steers weaned for approximately 8 months prior to shipping. However, meloxicam, may be beneficial in other populations of higher risk calves that have experienced additional stresses or inflammatory events. Additional research needs to be performed in order to evaluate meloxicam’s potential therapeutic effects in other populations of animals as well as further exploring the complex interplay of different stress sources and their relationship with disease. These data will be of interest to researchers and veterinarians working in the field of bovine immunology and stress physiology, as well as cattle producers.

Technical Abstract: The objective of this study was to investigate the effects of meloxicam administration prior to shipping on the maintenance of leukocyte function and the reduction of inflammation during and after a long-distance transportation event in cattle. Yearling mixed-breed beef steers (n = 60; 309.5 kg ± 5.3 kg) were randomly assigned to be either transported (TR) or non-transported controls (NTC) and received either 1 mg/kg meloxicam orally (TR-MEL, n = 20 and NTC-MEL, n = 10) or a placebo orally (TR-CON, n = 20 and NTC-CON, n = 10) in an unbalanced 2 x 2 factorial design. All NTC cattle were transported from Mississippi to Kansas on day -17 of the study and allowed to acclimate while the TR steers remained in Mississippi. On day -1, both TR and NTC steers were randomly administered either MEL or placebo and the TR steers were transported to Kansas from Mississippi and arrived on day 0. Blood samples were obtained from all steers on days -1, 0, and 3 for analysis of markers of leukocyte function and inflammation. Bronchoalveolar lavage samples were also obtained from the TR steers on days 0 and 3 for analysis of annexin A1 levels. Ocular thermographic images of TR steers were taken on days -1, 0, and 3. Rectal temperature probes continuously monitored temperature of TR steers after treatment with MEL or CON through day 2 post-transport. No clinical cases of bovine respiratory disease were observed during the study. Plasma MEL concentrations were greater in TR-MEL steers on day 0 than NTC-MEL steers (P < 0.01). Substance P concentrations were lower in NTC-MEL steers compared to all other groups (P < 0.01) with no significant effect of study day. Sampling time was associated with rectal temperature, ocular temperature, cortisol, haptoglobin, neutrophil L-selectin expression, neutrophil phagocytosis intensity, percentage of active neutrophils, red blood cell count, hematocrit, mean corpuscular hemoglobin concentration, total leukocyte count, and polymorphonuclear leukocyte count (P < 0.05). Steers in the TR group had greater (P < 0.01) values for haptoglobin, neutrophil L-selectin intensity, and polymorphonuclear leukocyte count than NTC steers. The concentration of Hp-MMP 9 was greater in TR-CON steers compared to NTC-CON steers on day 0 (P < 0.01). In this study, meloxicam did not have a statistically significant effect on the variables measured in these healthy steers and only some leukocyte and inflammatory markers differed in transported versus non-transported steers.