Early postpartum administration of sodium salicylate to multiparous dairy cattle is associated with alterations in feeding behavior up to 120 days in milk

Abstract Text: Previous research has indicated that the use of non-steroidal antiinflammatory drugs such as sodium salicylate following calving can alter milk yield later in lactation. In the current experiment, sodium salicylate was administered following calving, and cattle were observed through 120 days in milk (DIM). Cows in their second parity and greater were blocked by parity and alternately enrolled into 1 of 2 treatments following calving, receiving either drenches of water (CON) or drenches of 125 g of sodium salicylate dissolved in a similar volume of water (SAL) at approximately 24, 48, and 72 h postpartum. A total of 28 animals per treatment were enrolled in this experiment, and 42 of these animals (n = 21 cows/treatment) were included in feeding behavior measurements. Of these, 16 cows were in their third parity and greater, and 26 were in their second parity. Feeding behavior was measured by feed bunks suspended from load cells that continuously monitored bunk weight. For all feeding behavior responses, variables (meal weight, meal length, number of meals/d, and intermeal interval) were averaged by day, and daily responses were averaged by week for statistical analysis. No differences were detected due to treatment for milk yield, energy-corrected milk (ECM), or DMI; however, a significant parity by treatment interaction was observed (P = 0.03), where SAL decreased intake in second parity cows but not cows in their third parity and greater. This resulted in a tendency for a treatment by parity interaction for milk yield:DMI (P = 0.08) and a significant interaction between treatment and parity on ECM:DMI (P = 0.02). Similarly, a significant interaction between parity and treatment was observed for average meal weight (P = 0.04), with no difference between treatments in second parity animals but increased average meal weight for older cows receiving SAL. Treatment with SAL was associated with fewer daily meals and greater average meal length (P = 0.03). A tendency for an interaction between treatment and week was also observed for intermeal interval (P= 0.06). For all feeding behavior variables measured, responses to treatment were delayed by at least 5 wk following administration. In conclusion, despite a failure to detect differences due to treatment in milk production or intake, postpartum treatment with sodium salicylate resulted in subtle and prolonged differences in feeding behavior in multiparous cows.

Keywords: feeding behavior, inflammation, sodium salicylate