Evaluation of specific immunoglobulin A in nasal secretions and neutralizing antibodies in serum collected at multiple time points from young beef calves following intranasal or subcutaneous administration of a modified-live bovine respiratory syncytial virus vaccine.

OBJECTIVE: To determine anti-bovine respiratory syncytial virus (BRSV) antibody titers for nasal secretions and serum from beef calves following administration of a modified-live (MLV) BRSV vaccine. ANIMALS: 60 healthy newborn purebred beef calves. PROCEDURES: Calves were randomly assigned to 1 of 3 groups: intranasal (IN)-SC (IN MLV BRSV vaccine within 24 hours of birth and SC MLV BRSV vaccine at 2 months of age), SC-IN (SC MLV BRSV vaccine within 24 hours of birth and IN MLV BRSV vaccine at 2 months of age), or NO-IN (no vaccine within 24 hours of birth and IN MLV BRSV vaccine at 2 months of age). Nasal secretion and serum samples were collected for determination of anti-BRSV antibodies within 24 hours of birth and 2 and 6 months of age. RESULTS: Titers of anti-BRSV IgA antibodies in nasal secretions and BRSV neutralizing antibodies in serum were similar among groups at each sampling time. Within 24 hours of birth, nasal anti-BRSV IgA titers were negligible. At 2 months, mean nasal anti-BRSV IgA titers for calves in IN-SC, SC-IN, and NO-IN groups were 192.84, 224.49, and 114.71, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Concentrations of anti-BRSV IgA antibodies in the nasal secretions and BRSV neutralizing antibodies in the serum of young beef calves following an MLV BRSV vaccine protocol that consisted of IN or SC vaccine within 24 hours of birth and vice versa at 2 months of age were not different from that following only an IN MLV BRSV vaccine at 2 months of age. However, the lack of any differences may have been attributed to other factors.

Pharmacokinetics and pharmacodynamics of intravenous and transdermal flunixin meglumine in alpacas.

The aim of this study was to determine the pharmacokinetics and prostaglandin E2 (PGE2 ) synthesis inhibiting effects of intravenous (IV) and transdermal (TD) flunixin meglumine in eight, adult, female, Huacaya alpacas. A dose of 2.2 mg/kg administered IV and 3.3 mg/kg administered TD using a cross-over design. Plasma flunixin concentrations were measured by LC-MS/MS. Prostaglandin E2 concentrations were determined using a commercially available ELISA. Pharmacokinetic (PK) analysis was performed using noncompartmental methods. Plasma PGE2 concentrations decreased after IV flunixin meglumine administration but there was minimal change after TD application. Mean t1/2 λz after IV administration was 4.531 hr (range 3.355 to 5.571 hr) resulting from a mean Vz of 570.6 ml/kg (range, 387.3 to 1,142 ml/kg) and plasma clearance of 87.26 ml kg-1  hr-1 (range, 55.45-179.3 ml kg-1  hr-1 ). The mean Cmax, Tmax and t1/2 λz for flunixin following TD administration were 106.4 ng/ml (range, 56.98 to 168.6 ng/ml), 13.57 hr (range, 6.000-34.00 hr) and 24.06 hr (18.63 to 39.5 hr), respectively. The mean bioavailability for TD flunixin was calculated as 25.05%. The mean 80% inhibitory concentration (IC80 ) of PGE2 by flunixin meglumine was 0.23 µg/ml (range, 0.01 to 1.38 µg/ml). Poor bioavailability and poor suppression of PGE2 identified in this study indicate that TD flunixin meglumine administered at 3.3 mg/kg is not recommended for use in alpacas.

Pharmacokinetics and pharmacodynamics of intravenous and transdermal flunixin meglumine in meat goats.

The aim of this study was to determine the pharmacokinetics and prostaglandin E2 (PGE2 ) synthesis inhibiting effects of intravenous (IV) and transdermal (TD) flunixin meglumine in eight adult female Boer goats. A dose of 2.2 mg/kg was administered intravenously (IV) and 3.3 mg/kg administered TD using a cross-over design. Plasma flunixin concentrations were measured by LC-MS/MS. Prostaglandin E2 concentrations were determined using a commercially available ELISA. Pharmacokinetic (PK) analysis was performed using noncompartmental methods. Plasma PGE2 concentrations decreased after flunixin meglumine for both routes of administration. Mean λz -HL after IV administration was 6.032 hr (range 4.735-9.244 hr) resulting from a mean Vz of 584.1 ml/kg (range, 357.1-1,092 ml/kg) and plasma clearance of 67.11 ml kg-1  hr-1 (range, 45.57-82.35 ml kg-1  hr-1 ). The mean Cmax , Tmax, and λz -HL for flunixin following TD administration was 0.134 µg/ml (range, 0.050-0.188 µg/ml), 11.41 hr (range, 6.00-36.00 hr), and 43.12 hr (15.98-62.49 hr), respectively. The mean bioavailability for TD flunixin was calculated as 24.76%. The mean 80% inhibitory concentration (IC80 ) of PGE2 by flunixin meglumine was 0.28 µg/ml (range, 0.08-0.69 µg/ml) and was only achieved with IV formulation of flunixin in this study. The PK results support clinical studies to examine the efficacy of TD flunixin in goats. Determining the systemic effects of flunixin-mediated PGE2 suppression in goats is also warranted.