2008 DEC 22 - (VerticalNews.com) -- According to a study from Bangkok, Thailand, "The giant river shrimp (Macrobrachium rosenbergii), a native species of Thailand, is either exported for commercial purposes or supplied to meet the local requirements in Thailand. Limited pharmacokinetic information of the major antibiotic, oxytetracycline (OTC), is available for this freshwater shrimp."

  "The purpose of the present study was to investigate the muscle tissue kinetics of OTC in M. rosenbergii following either intramuscular (i.m.) or oral (p.o.) administration at two dosages of 11 and 22 mg/kg body weight (b.w.). The concentration of OTC in shrimp tissues was measured using high-performance liquid chromatography (HPLC) equipped with a fluorescence detector. Muscle tissue concentrations were below the detection limit (LOD, 0.1 mu g/g) after 96 and 120 h, following i.m. and p.o. administration, respectively. Peak muscle concentrations (C-max) were 3.47 and 1.73 mu g/g after i.m. and p.o. administration at a single dose of 11 mg/kg b.w. whereas they were 6.03 and 2.51 mu g/g at a single dose of 22 mg/kg b.w., respectively. A noncompartment model was developed to describe the pharmacokinetics of OTC in the giant freshwater shrimp. The terminal half-lives of OTC were 28.68 and 28.09 h after i.m. and p.o. administration at a single dose of 11 mg/kg b.w., but 29.95 and 27.03 h at a single dose of 22 mg/kg b.w., respectively. The relative bioavailability was 82.32 and 64.67% following i.m. and p.o. administration, respectively. Based on the pharmacokinetic data, i.m. and p.o. administration with OTC at a dose of 11 mg/kg b.w. would be appropriate for use in giant freshwater shrimp farming," wrote A. Poapolathep and colleagues, Kasetsart University ...read more

  2008 DEC 22 - (VerticalNews.com) -- According to a study from Buenos Aires, Argentina, "The purpose of this study was to describe and compare the pharmacokinetic properties of different formulations of erythromycin in dogs."

  "Erythromycin was administered as lactobionate (10 mg/kg, IV), estolate tablets (25 mg/kg p.o.) and ethylsuccinate tablets or suspension (20 mg/kg p.o.). After intravenous (i.v.) administration, the principal pharmacokinetic parameters were (mean +/- SD): AUC((0-infinity)) 4.20 +/- 1.66 mu g.h/mL; C-max 6.64 +/- 1.38 mu g/mL; V-z 4.80 +/- 0.91 L/kg; Cl-t 2.64 +/- 0.84 L/h.kg; t(1/2 lambda) 1.35 +/- 0.40 h and MRT 1.50 +/- 0.47 h. After the administration of estolate tablets and ethylsuccinate suspension, the principal pharmacokinetic parameters were (mean +/- SD): C-max, 0.30 +/- 0.17 and 0.17 +/- 0.09 mu g/mL; t(max), 1.75 +/- 0.76 and 0.69 +/- 0.30 h; t(1/2 lambda), 2.92 +/- 0.79 and 1.53 +/- 1.28 h and MRT, 5.10 +/- 1.12 and 2.56 +/- 1.77 h, respectively," wrote G.A. Albarellos and colleagues ...read more

  2008 DEC 22 - (VerticalNews.com) -- According to recent research from the United States, "Maropitant (Cerenia (TM)), a selective neurokinin(1) receptor antagonist, was evaluated for safety and efficacy in treatment and prevention of acute vomiting due to various etiologies in dogs in a randomized clinical trial. Two-hundred seventy-eight dogs were enrolled from 29 veterinary hospitals."

  "Two-hundred fifty-two were evaluable for efficacy, while 275 were evaluable for safety. A randomized block design was utilized (three maropitant- and one placebo-treated dog per block). Initial treatment was maropitant at 1 mg/kg body weight (0.45 mg/lb) or an equivalent volume of saline (placebo) administered subcutaneously. On the subsequent 1 to 4 days, maropitant or placebo (dependent on allocation) was administered subcutaneously or orally at approximate 24-h intervals as needed. Oral doses were administered as maropitant tablets using unit dosing to deliver a minimum dose of 2 mg/kg body weight (0.9 mg/lb) or equivalent numbers of similar placebo tablets. Dogs and housing were observed twice daily for evidence of vomiting. Emesis was significantly (P <= 0.0012) reduced in maropitant-treated dogs as 50% (32/64) of placebo-treated dogs continued to vomit compared to only 21.8% (41/188) of maropitant-treated dogs. Post-treatment clinical signs were consistent with clinical diagnoses and judged not to be treatment related," wrote D.S. Ramsey and colleagues ...read more