No description available.

Call number: LD2668 .T4 1955 W67 / Master of Science

LD2668 .T4 1962 O88

Master of Science / Department of Clinical Sciences / Daniel Thomson / A total of 400 head of naturally parasitized commercial feedyard cattle (subset of 40 hd/pen; 10 pens) were utilized to compare trade name ivermectin pour-on and a generic ivermectin pour-on. The efficacy of each product was measured by obtaining rectal fecal egg counts on day 0 and day 14 using a Modified Wisconsin sugar float with centrifugation from rectal fecal samples and calculating fecal egg reduction post treatment. There were no differences in net egg count reduction between treatments (P= 0.15) at 14 days post-treatment application. Regardless of treatment, only 26% of animals had a fecal egg count reduction of >90% and only 35% achieved a FECR of >80% which is low considering 90% reduction is the accepted efficacy level. Cattle treated with the generic pour-on had improved average daily gains (ADG) compared to cattle treated with the trade name pour-on P = 0.02. This study demonstrated decreased efficacy of both products with a FECR of less than 90% within a commercial feedyard environment.

Call number: LD2668 .T4 1957 L33 / Master of Science

Two common nematodes that affect young horses are cyathostomes (small strongyles) and Parascaris equorum (ascarids). It has been recently found that populations of these nematodes are resistant to common anthelmintics used to control them. Small strongyles have been found to be resistant to pyrantel and fenbendazole, while ascarids have been found to be resistant to ivermectin. This represents a unique dilemma in controlling the gastrointestinal nematode population in the foal. It has been shown in other host species that combination anthelmintics can be used to successfully treat resistant nematodes. The current study utilized 28 foals and was conducted from April to November 2007. The foals were allocated into age cohorts and randomly assigned a treatment regimen. Group I was administered ivermectin at 0.2 mg/kg BW. Group II was administered ivermectin at 0.2-mg/kg BW and pyrantel pamoate at 6.6 mg/kg BW. Group III was administered ivermectin at 0.2-mg/kg BW and fenbendazole at 10 mg/kg BW. Group IV was administered pyrantel pamoate at 6.6 mg/kg BW and fenbendazole at 10 mg/kg BW. Fecal samples were collected at time of treatment and two wk post treatment to determine effectiveness in removing egg producing adult nematodes. Each age cohort was then treated 30 d later with a different anthelmintic or combination. That is, foals in group I were treated as those in group II, group II to treatment III, group III to treatment IV, and group IV to treatment I. Over a period of 4 mo, each foal received at least one treatment in consecutive order. The difference of egg counts (pre-treatment minus post-treatment) for small strongyles treated with ivermectin (IVM) was 29.39 eggs per g (EPG), 5.44 EPG for ivermectin with pyrantel (PRT), 3.85 EPG for ivermectin with fenbendazole (FBZ), and -8.32 EPG for pyrantel with fenbendazole. There was a significant difference when comparing IVM to IVM PRT (P = 0.0018), IVM vs. IVM FBZ (P = 0.0010), and IVM vs. PRT FBZ (P < 0.0001). IVM was more effective than each of the other treatments. There was no influence of treatment on ascarid EPG (P > 0.1184).

Call number: LD2668 .T4 1955 M68 / Master of Science

No description available.

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of biophysics and physical chemistry Candidate: Šárka Slezáková Supervisor: Ing. Vladimír Kubíček, CSc. Title of diploma thesis: HPLC Determination of Benzimidazoles In this thesis we have investigated the possibility of establishing benzimidazole with HILIC chromatography using a chromatographic column Ascentis Express HILIC 10.0 cm x 3.0 mm; 2.7 microns. Two groups of benzimidazoles were tested. The first one was focused on albendazole and its metabolites. Experiments with these substances did not produce satisfactory results, because the mobile phase composition which enables separation of the studied analytes was not found. The second group was formed by flubendazole and its reduced and hydrolyzed form. In this case, several mobile phase compositions were tested. Finally, distribution of individual analytes in a mixture, using a mobile phase ACN:HCOOH 0.03 mol/l (90:10), was successfully achieved. Ricobendazol was chosen as an internal standard. When separation conditions were found, calibration curve for the determination of reduced flubendazole in biological samples was subsequently constructed using ricobendazol as the internal standard with the use of fluorescence detection. Keywords: HILIC, HPLC, albendazole,...

Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Dominika Sobotová Tutor: PharmDr. Ivan Vokřál, Ph.D. Title of diploma thesis: Pharmacokinetics of ivermectin in the sheep feces Key words: ivermectin, pharmacokinetics, sheep, anthelminthic Infection with internal parasites (endoparasites) is one of the most common diseases in sheep. Infection with these parasites mainly with the barber's pole worm (Haemonchus contortus) causes considerable economic losses and has a significant impact on sheep productivity. Anthelmintics, including ivermectin, are used for treatment. Ivermectin belongs to the class of macrocyclic lactones and is characterised by broad spectrum and low toxicity. On the other hand, it poses a risk to the environment in form of residues that are excreted in feces by treated individuals. The aim of this study was to determine the excretion profile of ivermectin in sheep subcutaneously administered in a standard dose 0,2 mg/kg of body weight. UHPLC/MS/MS method was used for the analysis of ivermectin fecal concentration. Based on the obtained results we determined basic pharmacokinetic parameters which includes time to achieve maximum concentration (tmax), maximum concentration (cmax), area under the curve (AUC) and mean residence...