OXYTETRACYCLINE INTERACTION WITH WATER HARDNESS: IMPACT ON BIOAVAILABILITY IN FED AND FASTED PIGLETS

MARTÍNEZ, GUADALUPE; DECUNDO, JULIETA MARÍA; PÉREZ GAUDIO, DENISA SOLEDAD; ROMANELLI, AGUSTINA; AMANTO, FABIÁN A.; DIEGUEZ, SUSANA NELLY; FERNÁNDEZ PAGGI, MARÍA BELÉN; SORACI, ALEJANDRO LUIS

Wroclaw

Congreso; 14th International Congress of the European Association for Veterinary Pharmacology and Toxicology; 2018

European Association for Veterinary Pharmacology and Toxicology (EAVPT) and the European College of Veterinary Pharmacology and Toxicology (ECVPT)

The aim of this study was to evaluate the impact of water hardness and presence of food in gastrointestinal tract (GIT) on Oxytetracycline (OTC) bioavailability, Cmax and Tmax in weaning piglets.OTC dissolution profiles in HPLC grade (pH 6.0), hard (400 mg/L CaCO3, pH 9.0) and soft (40 mg/L CaCO3, pH 7.3) water were studied by in vitro assays performed in quadruplicate following USP 40 NF 35 guide. OTC chloride 50% powder formulation was added to the water and samples were collected at standardized intervals.Absolute BA was assessed following a completely randomized design. 16 healthy weaning piglets were divided in 4 groups. All animals received an IV dose (40 mg/kg BW OTC) to obtain reference blood concentration-time curves. An appropriate wash out period was left before administration of the treatments. Two groups received an oral dose of 40 mg/kg BW OTC in soft water after overnight fasting (S1) or without fasting (S2), and two groups received the same treatment in hard water in fasted (H1) or fed (H2) state. Blood samples were collected at standardized times by jugular catheterism technique and analyzed by HPLC-UV. PKSolution® was used to obtain pharmacokinetic parameters. OTC In vitro dissolution was 100, 89 and 80% in HPLC grade, soft and hard water respectively.Group S1 showed higher BA (6.13 ± 1.99%) than groups H1 (2.83 ± 0.44%) p=0.018, S2 (3.64 ± 1.46%) p=0.091 and H2 (2.00 ± 0.28) p=0.006. S1 Cmax was the highest, being p