Prepartum anti-inflammatory therapies in Holstein dairy cows blocked by parity and body condition score group: Effects on metabolic stress, systemic inflammation, performance, and health.

The objective of this study was to assess the effects of prepartum administration of anti-inflammatory therapies on BCS, BHB concentration, haptoglobin (HP) concentration, milk yield, milk components, rumination time, clinical health events, and reproductive performance in Holstein dairy cows. At 14 d before the expected calving date, cows (parous [PAR]; n = 170) and heifers (nulliparous [NUL]; n = 63) were blocked by BCS group (optimal [OPT] = 3-3.5; over-conditioned cows [OVERC; BCS ≥3.75 points]) and parity (NUL; PAR) and randomly allocated to 1 of 3 treatment groups: (1) ASA (n = 78): receive one oral administration of acetylsalicylic acid (4 boluses; 480 grain/bolus); (2) MEL (n = 76): receive one oral administration with meloxicam (1 mg/kg BW), or (3) PLC (n = 77): receive one oral treatment with gelatin capsules filled with water. Body condition score was assessed, and blood samples were collected, weekly starting 1 wk before treatment until 3 wk after calving. Daily milk yields and daily rumination times were collected from on-farm computer records. Dairy Herd Improvement Association monthly test data were collected to assess milk yield, SCC, and milk components. Furthermore, health events, culling rate, and reproductive performance data were collected from on-farm computer records. The data were analyzed using MIXED, GLIMMIX, and LIFETEST procedures of SAS as a randomized complete block design. On average, MEL-NUL cows produced 4.77 ± 0.93 kg/d and 4.81 ± 0.92 kg/d more milk from wk 6 to 21 of lactation compared with ASA-NUL and PLC-NUL cows, respectively. Similarly, a week by treatment by body condition group interaction was present, where OVERC cows treated with MEL produced more milk from wk 10 to 15 of lactation compared with ASA-OVERC and PLC-VERC cows. Parous cows treated with ASA had lower BCS compared with PAR cows treated with MEL or PLC. A lower percentage of OVERC cows treated with ASA became sick in the first 60 DIM compared with MEL-OVERC and PLC-OVERC cows (ASA = 23.88% ± 7.26%, MEL = 46.36% ± 8.57%; PLC = 46.74% ± 8.53%). Parous cows treated with ASA had a higher hazard ratio to become pregnant by 300 DIM compared with PAR MEL cows. Although the study was not sized for finding treatment differences in blocking criteria groups, these results suggest that treatment with prepartum anti-inflammatory therapies may have positive effects on milk yield and postpartum health in specific groups of cows, such as NUL and OVERC cows, although it may not be recommended for other animal categories, such as parous cows and cows with optimal BCS. Larger studies are needed to strengthen the associations observed in this study.