Diclazuril

Diclazuril nonlinear mixed-effects pharmacokinetic modelling of plasma concentrations after oral administration to adult horses every 3-4 days.[Pubmed:30503548]

Vet J. 2018 Dec;242:74-76.

The purpose of this study was to determine if a low dose of Diclazuril (0.5mg/kg of 1.56% Diclazuril pellets) given to six healthy adult horses every 3-4 days for a total of five administrations would achieve steady-state plasma concentrations known to be inhibitory to Sarcocystis neurona and Neospora caninum. Blood was collected via venipuncture immediately before (trough concentrations) and 10h after (peak concentrations) each Diclazuril administration and analysed by high-pressure liquid chromatography. The mean population-derived peak concentration was 0.284mug/mL and the mean terminal half-life was 1.6 days, but with a large variation. Thus, low dose Diclazuril pellets produce steady-state plasma drug concentrations known to inhibit S. neurona (0.001mug/mL) and N. caninum (0.1mug/mL).

Efficacy of Sulphachloropyrazine, Amprolium Hydrochloride, Trimethoprim-Sulphamethoxazole, and Diclazuril against Experimental and Natural Rabbit Coccidiosis.[Pubmed:30426022]

J Vet Med. 2018 Oct 23;2018:5402469.

There are no anticoccidial drugs labelled for rabbits in Kenya and those available are used as extra labels from poultry. The drugs are used in rabbits with limited knowledge of their efficacy and safety. The aim of this study was to determine the efficacy of sulphachloropyrazine, amprolium hydrochloride, and trimethoprim-sulphamethoxazole relative to Diclazuril when used curatively against experimental and natural rabbit coccidiosis. In a controlled laboratory trial, sixty (60) rabbits were randomly allocated to six treatment groups, namely, 1A, 2B, 3C, 4D, 5E, and 6F, each with 10 rabbits. Groups 2B, 3C, 4D, 5E, and 6F were experimentally infected with mixed Eimeria species while group 1A served as uninfected-untreated (negative) control group. Four of the infected groups were treated with sulphachloropyrazine (5E), amprolium hydrochloride (2B), trimethoprim-sulphamethoxazole (6F), and Diclazuril (4D) using dosages recommended by manufacturers. Group 3C served as infected-untreated (positive) control. A field efficacy trial in naturally infected rabbits was then undertaken. The results revealed that sulphachloropyrazine and Diclazuril were effective against rabbit clinical coccidiosis by significantly reducing oocyst counts from 149.00+/-110.39 x 10(4) to 3.31+/-0.86 x 10(4) Eimeria spp. oocysts per gram of feces (opg) and 59.70+/-12.35 x 10(4) to 0.0+/-0.0 x 10(4) opg, respectively, in the laboratory trial. Similarly, sulphachloropyrazine and Diclazuril recorded reduced oocyst counts in the field trial from 280.33+/-44.67 x 10(3) to 0.44+/-0.14 x 10(3) opg and 473.44+/-176.01 x 10(3) to 0.0+/-0.0 x 10(3) opg, respectively. Still, sulphachloropyrazine and Diclazuril showed superior efficacy by registering lesion scores and fecal scores close to those of uninfected untreated control group. Trimethoprim-sulphamethoxazole recorded a satisfactory efficacy in the field trial by recording reduced oocyst counts from 266.78+/-37.03 x 10(3) to 0.75+/-0.11 x 10(3) opg but was not efficacious in the laboratory trial. Amprolium hydrochloride was not efficacious against clinical coccidiosis in both the experimental and field trials.

Revision of a European Union Official Method to Enforce Legal Provisions: The Case of Diclazuril.[Pubmed:30381090]

J AOAC Int. 2019 Mar 1;102(2):646-652.

Background: Diclazuril is a coccidiostat currently authorized as feed additive in the European Union (EU), with a legal limit set at 1 mg/kg. For official control, an official EU method based on reversed-phase HPLC coupled with UV detection at 280 nm needs to be applied. Recently, the EU Reference Laboratory for feed additives was informed that the recovery rate for Diclazuril was very low when implementing this method and performed experiments demonstrating that the indicated sorbent mass of the solid-phase extraction (SPE) was too low. Objective: Therefore, the paper presents a modified method protocol and the results of an interlaboratory study, performed on two compound feedingstuffs containing Diclazuril around the legal limit. Methods: The official method was modified by using a higher SPE sorbent mass and was further subjected to validation. Results: The obtained values for the relative standard deviation for repeatability were 4.5 and 11.2%, and the corresponding values for the relative standard deviation for reproducibility were 14.3 and 18.1%; the calculated HorRat values were 0.95 and 1.14. Furthermore, acceptable mean recovery values of 98 and 111% were obtained for the two test materials, respectively. Conclusions: Based on the obtained performance profile, it was concluded that the modified official method was fit for purpose. In consequence, the official EU method will be corrected accordingly. Highlights: The highlights of this work are reflected by the following terms, namely Diclazuril, correction of EU official method, and interlaboratory study.

In vitro activity of natural and chemical products on sporulation of Eimeria species oocysts of chickens.[Pubmed:29426468]

Vet Parasitol. 2018 Feb 15;251:12-16.

This study was designed to investigate the ability of two herbal extracts and different chemical substances to inhibit or disrupt sporulation of Eimeria species oocysts of the chickens. The two herbal extracts were Allium sativum (garlic) and Moringa olifiera while the chemical substances included commercial disinfectants and Diclazuril. Field isolates of Eimeria oocysts were propagated in chickens to obtain a continuous source of oocysts. The collected unsporulated oocysts (10(5)oocysts/5ml) were dispensed into 5cm Petri dish. Three replicates were used for each treatment. The treated oocysts were incubated for 48h at 25-29 degrees C and 80% relative humidity. The results showed that herbal extracts, the commercial recommended dose of Dettol, TH4, Phenol, Virkon((R))S, and Diclazuril 20% have no effect on the sporulation. While Sodium hypochlorite showed a significant degree of sporulation inhibition reached to 49.67%. Moreover, 70% ethanol, and 10% formalin showed 100% sporulation inhibition. It was concluded that 70% ethanol and 10% formalin are the most effective methods to inhibit Eimeria species sporulation.