Effect of Postpartum Treatment with Non-Steroidal Anti-Inflammatory Drugs (NSAID) on Reproductive Performance and Removal from the Herd in Dairy Cattle through Mid-Lactation

Abstract Text: Many studies have evaluated the use of postpartum NSAID treatment in dairy cattle, but few have monitored long-term responses to such treatments. To address this limitation in the literature, 153 multiparous dairy cattle were blocked by breed, dystocia, and twin births, and assigned to 1 of 3 treatments within 12-36 h after parturition. Treatments were 1 placebo bolus on the first day after parturition and 3 consecutive daily drenches of sodium salicylate (125 g/cow/d) beginning on the first day after parturition (SS); 1 bolus of the NSAID meloxicam (675 mg/cow) and 3 drenches of an equal volume of water (M); and 1 placebo bolus and 3 drenches of water (CON). As previously reported, milk production was increased in the first 9 weeks of lactation by either NSAID treatment in cows experiencing dystocia, but in cows that calved normally, milk yield increased only after treatment with M. The objective of this analysis was to determine if NSAID treatment influenced reproductive performance and risk of removal from the herd in approximately the first half of lactation (up to 160 DIM). Removal rate from the herd and time to pregnancy were evaluated by Cox regression proportional hazard analysis, and incidence of disease was tested by Fisher’s exact test. Treatment, breed, dystocia, twin births, and their interactions did not (P >0.1) affect time to pregnancy or first service pregnancy per AI (21.9%). A total of 33 cows left the herd during the period investigated, and M cows were (P = 0.02) removed from the herd at a slower rate than CON (AHR = 0.33, 95% CI = 0.13, 0.84), with no effect observed for SS (P = 0.28, AHR = 0.66, 95% CI = 0.30, 1.42). Treatment did not affect the risk of leaving the herd due to mastitis, low milk production, injury, lameness, or death (all P > 0.1). However, M tended to decrease the risk of culling due to other diseases—including respiratory disease, displaced abomasum, and suspected metabolic disorders—compared to CON (n = 7 CON vs. 1 M; P = 0.06). Furthermore, 4 of the CON cows in this category were removed from the herd before 19 DIM, whereas the M cow was removed at 149 DIM. These results indicate that in addition to elevated milk production, postpartum administration of M may have beneficial effects on dairy cow longevity.

Keywords: inflammation, NSAID, cull rate, reproduction