Objectives of this study were to determine effects of meloxicam administered in 2 forms on IgG uptake, growth, and health of preweaned calves. Sixteen Holstein bulls and 14 heifers with a body weight (BW) of 44.3 ± 5.24 kg were blocked by birth date in a randomized complete block design. Calves were removed from the dam before suckling, weighed, and randomly assigned to 1 of 3 treatments: (1) colostrum replacer (CR) at 0 h with no meloxicam (control; CON), (2) 1 mg/kg of BW of meloxicam in pill form before CR (PL), or (3) 1 mg/kg of BW of meloxicam mixed in solution with CR (SL). Calves were fed 675 g of dry matter of CR, providing a volume of 3 L and 180 g of IgG. Blood samples were collected at 0 h to analyze initial IgG and ketone concentrations, and at 6, 12, 18, and 24 h to analyze IgG uptake. At 24 h, calves were fed 432 g of dry matter of 24% crude protein milk replacer (MR) split in 2 feedings, and free choice starter and water until 42 d. Weekly blood samples were analyzed for glucose, plasma urea nitrogen, and ketone concentrations. Time of consumption of MR, BW, length, hip and withers height, and heart girth were recorded weekly. All calves achieved adequate transfer of immunity. Meloxicam did not affect apparent efficiency of absorption, serum total protein, or IgG uptake at 6, 18, and 24 h; however, meloxicam-treated calves had lesser IgG concentrations at 12 h (24.40 and 22.59 g/L for PL and SL, respectively) compared with CON (28.47 g/L). Meloxicam treatment did not affect BW. Calves that received PL tended to gain length at a faster rate (0.24 cm/d) than those that received SL (0.19 cm/d). Meloxicam treatment did not affect MR intake, time of consumption of MR, total dry matter intake, or feed efficiency. Meloxicam-treated calves tended to consume more starter (560.4 and 515.4 g/d for PL and SL, respectively) than those that received CON (452.6 g/d). Ketone levels tended to be greater in meloxicam-treated calves (0.15 and 0.17 mmol/L for PL and SL, respectively), suggesting improved rumen development compared with those that received CON (0.12 mmol/L). Meloxicam treatment did not affect plasma urea nitrogen . Glucose concentrations of calves that received PL (73.2 mg/dL) were less than those that received SL (83.3 mg/dL). Results of this study suggest that meloxicam given at 0 h offers positive effects on starter intake, and possibly rumen development, of preweaned dairy calves. Treatment PL, as compared with SL, offered positive results for rumen development, indicated by lower blood glucose levels.
