The Effect of Delivery Method on the Pharmacokinetic Properties of Meloxicam in Pre-Weaned Dairy Calves with Diarrhea

Abstract

The non-steroidal anti-inflammatory drug meloxicam is commonly used as adjunct therapy for neonatal calf diarrhea to control pain and inflammation. The objective of this study was to compare the pharmacokinetics of meloxicam in diarrheic pre-ruminant dairy calves dosed either orally or subcutaneously. Twelve pre-ruminant male dairy calves with mild to moderate diarrhea were randomly assigned to receive one of four treatments (three per group): subcutaneous meloxicam (SM, 0.5 mg/kg body weight); an oral bolus meloxicam suspension (OM, 1 mg/kg body weight); an oral meloxicam suspension added to a feeding of oral electrolytes (EM, 1 mg/kg body weight); and an oral meloxicam suspension added to a feeding of milk replacer (MM, 1 mg/kg body weight). The predicted pharmacokinetic parameters for OM, MM, EM, and SM groups were: half-life (56.8 ± 21.7 vs. 136.0 ± 26.6 vs. 85.2 ± 21.7 vs. 36.3 ± 21.7 h), Cmax (4.3 ± 0.4 vs. 3.7 ± 0.4 vs. 3.9 ± 0.4 vs. 2.1 ± 0.4 µg/mL), Tmax (13.3 ± 4.0 vs. 10.7 ± 4.0 vs. 13.3 ± 4.0 vs. 2.7 ± 4.0 h), and AUC 0-∞ (383.4 ± 126.8 vs. 877.8 ± 155.3 vs. 457.1 ± 126.8 vs. 126.4 ± 126.8 h * µg/mL). Oral meloxicam, especially MM, had extended elimination phases relative to SM. All meloxicam therapies provided effective therapeutic levels but all oral therapies (1 mg/kg) provided longer durations of activity than injectable meloxicam (0.5 mg/kg).

Pharmacokinetics of meloxicam in pre‐ruminant calves after intravenous, oral, and subcutaneous administration

“…After SC administration of meloxicam (0.5 mg/kg), C max (1.91 ± 0.27 μg/mL) was in line with a recent study on young calves with mild to moderate diarrhoea (2.1 ± 0.4 μg/mL) (Shock et al, 2020). Interestingly, mean T max (7.6 h) in our study's healthy calves was longer when compared to the mean T max (2.7 h) found in calves with diarrhoea (Shock et al, 2020). Presumably, this difference in the T max in our study could be explained by the blood sampling protocol, which was more frequent and over a more extended period.…”

Repeated ultrasound‐guided saphenous and sciatic nerve block in a calf with tibial comminuted fracture undergoing surgical stabilisation

“…However, there are few studies of meloxicam administration in the neonatal calf, 17,18 considering the age of our patient and the potential injury in his undeveloped systems, the dose was lowered to 0.2 mg/kg intravenously. Parenteral route was preferred over oral administration due to differences in bioavailability and half‐life between both routes of administration 19,20 …”

“…Parenteral route was preferred over oral administration due to differences in bioavailability and half-life between both routes of administration. 19,20 Bupivacaine and ropivacaine are considered long-lasting local anaesthetics and therefore commonly employed during peripheral nerve blockade, preventing nociceptive stimulus not only in the intraoperative period but also in the postoperative period; however, they were not used due to EU legislation.…”

Can diarrhea affect the pharmacokinetics of racecadotril in neonatal calves?

“…Positive samples on the fast antigen test in calves with diarrhea were confirmed by light microscopy for Cryptosporidium parvum and with ELISA for the presence of K99 E. coli (Monoscreen AgELISA E. coli K99, Bio‐X Diagnostics, Rochefort, Belgium), bovine rotavirus (Monoscreen AgELISA bovine rotavirus, Bio‐X Diagnostics, Rochefort, Belgium), and coronavirus (Monoscreen AgELISA bovine coronavirus, Bio‐X Diagnostics, Rochefort, Belgium) antigens. In determining calves with sick, besides the degree of dehydration, other clinical observations and findings such as fecal consistency, fever, tachycardia, tachypnea, anorexia, difficulty in standing, and maintaining sternal recumbency stated by Schock et al (2020) and Ok et al (2020) were also taken into account.…”