CYSTODEZ EFFICACY AGAINST EIMERIA SPP. OOCYST IN YOUNG CATTLE TESTED UNDER PRODUCTION CONDITIONS

To control parasitic protozoa in young cattle, preparations and agents have been proposed against both endogenous and exogenous stages. A search for control means of the exogenous stage of parasitic protozoa remains the most problematic. Among the means used on farms against the eimeria exogenous stage, it is necessary to note aqueous solutions of caustic alkalis which do not meet modern demands of veterinary practice in their efficacy. Based on the above, we prepared a multicomponent disinfection agent, Cystodez. The 4% Cystodez efficacy against eimeria in calves was established in a production test by artificially placing eimeria oocysts on control sites, in comparison with the base preparation 4% phenol, with a 2-hour exposure. The test was carried out on a cattle farm in the Moscow Region in AugustSeptember 2023, in cowshed No. 4, where preliminary cleaning and disinfection were performed; 3 sites of 1 m2 each were selected. At the beginning of the test, 20,000 Eimeria spp. oocysts diluted with 50 mL of distilled water were applied to each experimental site. After 20 minutes, 4% Cystodez was applied to the first site at a rate of 0.5 L/m2 with a 2-hour exposure; 4% phenol solution was applied to the second site at a rate of 0.5 L/m2 and a 2-hour exposure, and distilled water was applied to the control site. After the time expired, swabs were taken from the surface of each site, and a lysis test was conducted in laboratory conditions for 24 hours, and the material was used for a bioassay on 15 6-month-old calves. In the examination at 12–18 days after the prescribed material, eimeria oocysts were found in the calves' faeces. All calves in the control group were infected with eimeria oocysts; the number of eimeria in 1 g of faeces was 2,760. In the first group of calves that were given a suspension treated with 4% Cystodez, the number of oocysts in 1 g of faeces was 142. The Cystodez intense-effectiveness was 94.9%; in the second group of calves that were given the suspension treated with 4% phenol, the number of oocysts in 1 g of faeces was 520, and the phenol intense-effectiveness was 81.16%.