The influence of coccidiostatic Baycox on the course of coccidiosis in broiler chicken

The purpose of the research is to identify species of Eimeria spp. in chicken broilers suspected to be infected with coccidia and to determine the effect of coccidiostatics in the course of coccidiosis. Materials and methods. The study involved 20 six-week-old broiler chickens obtained from a farm heavily affected by coccidia (natural infection – a high oocyst incidence). Each group yielded 10 randomly picked chickens to be used in the experiment. The birds were divided into 2 groups 10 chickens each: control (I); Baycox-treated (II); Baycox was applied for 2 days in a concentration of 25 ppm in drinking water. Samples of broiler chickens’ droppings were tested qualitatively by the flotation method (Willis-Schlaaf) and then quantitatively by the McMaster technique. The chickens were killed 6 days post-treatment and their intestinal mean total lesion scores (MTLS) were graded 0 to 4 on an arbitrary scale described by Johnson and Reid (1970). Results and discussion. As a result of the research, six species of protozoa of the genus Eimeria were identified: E. acervulina, E. tenella, E. brunetti, E. maxima, E. mivati, E. necatrix, while E. necatrix and E. maxima were the dominant species. This proves the presence of such species as E. mivati, E. acervulina (76.34%) in the anterior segment of the intestine and E. necatrix, E. maxima (83.34%) – in the middle segment of the small intestine. Infections of E. brunetti broilers amounted to 51.11%. The most pathogenic species of E. tenella residing in the cecum was found in 37.53%. MTLS in the group of chickens that received Baycox was 0.33. The post-treatment oocyst indices in the second group amounted to 1 (1–50 oocysts in 1 g of faeces), in the control group MTLS was very high (2,5), the oocyst index exceeding 3.