Dr. Kassai Tibor - Dr. Murai Éva szerk.: Parasitologia Hungarica 8. (Budapest, 1975)
This paper reports the results obtained by a single high dose level treatment with bunamidine hydroxynaphthoate against E. granulosus as well as experiences with a medicated biscuit formulation developed in order to meet the requirements of an easy application. Limited comparative observations on the efficacy of bunamidine hydrochloride, niclosamide and cantrodifene to this parasite have also been made. Material and Methods LABORATORY EXPERIMENTS Animals. Dogs of both sexes and mixed breed over 4 months of age were used. Each was vaccinated against canine distemper and then treated by "Devermin" (Chinoin) to eliminate common tapeworms originating from natural infection. Infective material. For the experimental infection scolices were collected from pig livers containing hydatid cysts. Pooled hydatid fluid was passed through a syringe several times to obtain free individual scolices in the suspension. A dilution method was used to determine the concentration of viable scolices. Infective material was kept at 4°C overnight and used for infection within 30 hours of slaughter of the pigs. Experimental details. Three experiments were conducted involving a total of 113 dogs. Animals were orally infected with 30 000 (Exp, 2) or 50 000 (Exps. 1 and 3) scolices each, administered by syringe in 20 ml of fluid. All exposed animals developed infection with E. granulosus . On day 41 or 42 after infection a control group was allocated for each experiment (Groups D, H and K). The remainder were divided into groups, weighed and treated as indicated in Table 1. Results were assessed between days 3 and 19 after treatment by post mortem determination of the individual worm counts. Following about 20 hours of starvation dogs were killed, each small intestine removed, and divided into four parts of equal length. Each part was opened, the content carefully collected in a Petri dish, and mixed with the mucosal and submucosal layers of the intestinal segment stripped off gently with a knife. This material was examined in small quantities between compressed glassplates under dissecting microscope. All scolices were counted. In some heavily infected animals (Exp. 3) an aliquot sample was microscopically examined and the total number of scolices calculated on a weight basis. In all cases worm counts were made within 24 hours of autopsy. Criteria for assessment. In most groups animals both with low and high worm counts were found rendering calculation of group mean values rather pointless. Each control dog - except one animal - had a worm burden well in excess of 500 worms, the mean worm counts being 3370, 2447 and 13 225 in Groups D, H and K, respectively. Therefore, dogs found to harbour more than 500 scolices were classified as non recovered (NR), and those with fewer worms as recovered (R). Thus, anthelmintic efficiency is expressed by the combination of two parameters: by the proportion of dogs recovered after treatment and by the per cent reduction of the worm count of the recovered dogs as compared to the mean worm burden of the controls (Table 2). Drugs used 1. ) Bunamidine hydroxynaphthoate powder (Burroughs Wellcome and Co. ) 1x75 mg/kg in a 10% suspension with Carbowax 400 - Group A 1x100 mg/kg in a 10/o suspension with Carbowax 400 - Group B 1x100 mg/kg in biscuit formulation - Group E 1x100 mg/kg mixed with minced raw meat (in the food) - Group F Fig. 1. Experimental medicated biscuits containing 1 g bunamidine hydroxynaphtoate each (for 10 kg body weight)
