Measurement of haptoglobin after the time of dry-off and effects of a non-steroidal anti-inflammatory drug administered on the day of dry-off to Holstein dairy cows.

The objective of this study was to measure haptoglobin during the early dry period and to assess the effects of meloxicam administration at the time of dry-off on subsequent plasma haptoglobin concentrations, rumination time, culling, and milk production in the subsequent lactation. We measured haptoglobin at the time of dry-off and 48 h after dry-off to evaluate the change in haptoglobin in the early dry period, and possible differences between meloxicam treated and untreated cows (control = 120, meloxicam = 113). We also compared rumination time post-treatment (control = 117, meloxicam = 113), culling, and milk production for the first 21 days of the subsequent lactation (control = 417, meloxicam = 410) between meloxicam-treated and control cows after enrollment. There was a significant increase in haptoglobin across the first 48 h of the dry period (dry-off: 0.02 ± 0.01 g/L, 48 h post dry-off: 0.48 ± 0.02 g/L, P < 0.001), and treatment with meloxicam affected haptoglobin concentrations at 48 h post-enrollment (control: 0.55 ± 0.02 g/L, meloxicam: 0.42 ± 0.02 g/L, P < 0.001). Treatment with meloxicam decreased culling but did not affect rumination time or milk production.