title: Sulfadimethoxine in giant freshwater prawns (Macrobrachium rosenbergii): an attempt to estimate the withdrawal time by a population pharmacokinetic approach.
abstract: The fates of sulfadimethoxine (SDM) for different routes of administration were investigated in muscle tissue of giant freshwater prawns, Macrobrachium rosenbergii, following either intramuscular (i.m.) or gavage administration at a dosage of 50 mg/kg body weight (b.w.). The depletion patterns of SDM were also examined after medicated feed treatment at the feeding concentration of 10 g/kg of feed twice a day at a rate of 1% of total b.w. for five consecutive days. The concentration of SDM in prawn muscle tissue was measured using a high-performance liquid chromatography (HPLC) equipped with ultraviolet detector. Noncompartmental analyses were used to estimate basic pharmacokinetic parameters for the i.m. and gavage data, while a population model was developed to analyze the entire data set including the feed group. Using the Monte Carlo simulations, the withdrawal times (WT) for the orally administered SDM in feed supplement were determined. Maximum concentration of SDM was significantly higher in the i.m. than in the gavage group, and the area under the curve (AUC) value for relative bioavailability following gavage administration was 25.6%. Using Monte Carlo simulation, for a maximum residue limit (MRL) of 0.1 μg/g, the WT for muscle after oral administration of SDM in feed was estimated to be 67 h, while for a MRL of 0.2 μg/g, the WT was estimated to be of 54 h.
authors.affiliation: Department of Pharmacology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok, Thailand.
authors.forename: A
authors.initials: A
authors.lastname: Poapolathep
authors.affiliation: Department of Veterinary Sciences, University of Pisa, San Piero a Grado, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Giorgi
authors.affiliation: Toxalim, Université de Toulouse, INRA, INP-ENVT, INP-EI-Purpan, Université de Toulouse 3 Paul Sabatier, Toulouse, France.
authors.forename: P L
authors.initials: PL
authors.lastname: Toutain
authors.affiliation: Department of Pharmacology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok, Thailand.
authors.forename: S
authors.initials: S
authors.lastname: Poapolathep
authors.affiliation: Department of Pharmacology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok, Thailand.
authors.forename: K
authors.initials: K
authors.lastname: Imsilp
authors.affiliation: Faculty of Veterinary Technology, Kasetsart University, Bangkok, Thailand.
authors.forename: C
authors.initials: C
authors.lastname: Sakulthaew
authors.affiliation: Inland Fisheries Research and Development Division, Department of Fisheries, Ministry of Agriculture and Cooperatives, Bangkok, Thailand.
authors.forename: N
authors.initials: N
authors.lastname: Wannapat
authors.affiliation: Department of Pharmacology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok, Thailand.
authors.forename: N
authors.initials: N
authors.lastname: Klangkaew
mesh_terms: D000284:Administration, Oral; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D005618:Fresh Water; D007273:Injections, Intramuscular / Q000662:veterinary; D009132:Muscles / Q000378:metabolism*; D033541:Palaemonidae / Q000378:metabolism*; D013412:Sulfadimethoxine / Q000493:pharmacokinetics*
chemical_list: D013412:Sulfadimethoxine