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Dairy cows are increasingly predisposed to diseases in the periparturient time period due in part to immunosuppression. Dystocia amplifies the disease risk due to the increased tissue trauma and stress the animal endures during the lengthened parturition. To decrease the increased inflammatory response seen in dystocic animals and improve their well-being in the postpartum period, we administered either a potent steroid, dexamethasone (DEX), or a saline control (CON) to cows within 12 hours after a dystocic parturition. The inflammatory marker haptoglobin was measured as well as behavioral and production measures. We observed that primiparous DEX cows exhibited a greater haptoglobin concentration on d 3 and d 7 postpartum compared to primiparous CON cows. Behavior was seen to be altered between the treatments, with DEX cows having reduced locomotion and increased lying times in the week following parturition. These measures could indicate pain reduction, suggesting improved comfort. Milk yield was affected, with a reduction of 7.3 kg/d in multiparous DEX cows in comparison to CON cows for almost the entirety of the first month following dexamethasone treatment. No treatment effects were seen for milk production of primiparous cows. Additional research is needed for further investigation of the immunological and production effects of steroids on postpartum dairy cows, especially between parities. Master of Science in Life Sciences Dairy cows are most likely to develop metabolic diseases in the weeks leading up and following calving. This risk can be heightened in cows that experience a difficult calving process, most likely due to an increased inflammatory response. A potent steroid, dexamethasone, was assessed after a difficult calving to see if postpartum animal recovery is accelerated through dampening of the inflammatory response. Dairy cows were given either dexamethasone (DEX) or saline control (CON) within 12 hours after a difficult birth to counter the inflammatory response. Our study found that primiparous cows that received dexamethasone, exhibited a greater concentration of the inflammatory marker, haptoglobin, on d 3 and d 7 postpartum than in CON cows. This may be attributed to increased tissue trauma in first time calvings since there was no treatment difference in multiparous cows. Cows that received dexamethasone also had a reduction in locomotion and an increased amount of total lying time in the days following calving. Additionally, multiparous cows that received dexamethasone exhibited a reduction in milk production by 7.3 kg/d for almost the entirety of the first month following treatment. Future research needs to examine the long-term effects of dexamethasone on the mammary gland and the inflammatory response in different parity cows postpartum. |
