Improving animal welfare is a continuous process that requires that we evaluate the various treatment strategies that we use. Often our collective field experience in evaluating the efficacyof medications can differ from the current body of scientific evidence that is available to support that use. Dexamethasone (DEX) is a widely used immuno regulatory agent. Previous studies have suggested that pigs are less sensitive to the immuno suppression conferred by DEX and therefore more sensitive to the threat of bacterial endotoxins. Researchers wanted to do a deeper dive on that assumption. They developed an endotoxemia model using gram negative bacterial cell wall lipopoly saccharide (LPS) so that they could scientifically measure the effect of DEX treatments on a variety of endotoxemic responses in the pig, including sickness behaviour.
The researchers were able to demonstrate that DEX reduced the frequency of sickness behaviour following LPS challenge. In addition, they were able to show that DEX pre-treatment decreased cortisol, adrenocorticotropic hormone (ACTH), red blood cell, hemoglobin, hematocrit, and lymphocyte whereas glucose concentration was increased under both normal and endotoxemic conditions. By contrast, DEX decreased triglyceride, lactate, and IL-6 concentrations and increased platelet count only under an endotoxemic condition.
Take Home Message
Dexamethasone treatment protected the pigs in this study from inflammation and behavioural signs of sickness that are related to endotoxemia.
It is important to have strong scientific evidence that justifies the use of medications in pig production and this is especially true when the products are used in an off-label manner.
Sometimes the scientific evidence with respect to the usefulness of the therapies that we use has to catch up with the “boots on the ground” experience.
Submitted by Marty Misener, DVM
Ref:Li Z, Kanitz E, Tuchscherer M, Tuchscherer A, Metges CC, Trakooljul N, Wimmers K, Murani E.Kinetics of Physiological and Behavioural Responses in Endotoxemic Pigs with or without Dexamethasone Treatment.Int J Mol Sci. 2019 Mar 20;20(6). pii: E1393. doi: 10.3390/ijms20061393