EN
The western capercaillie breeding program is aimed at the restoration and reintroduction of this bird species in Poland. Parasitic invasions may be one of the factors limiting the breeding effects. The aim of the paper is to present the parasitologic situation in aviary breeding centres in Leżajsk and Wisła Forest Divisions. The study material included 38 samples of faeces of western capercaillie taken from the floor of the aviaries in the breeding centres in Leżajsk and Wisła Forest District. The faeces were studied using flotation, decantation and the quantitative McMaster methods. The presence of only two parasitic genera was detected. Based on the results of morphological analysis, the coccidia was classified as Eimeria lyruri, while nematode as the species Capillaria (syn. Aonchoteca) caudinflata. The total average prevalence of parasitic invasion in the studied samples was 60.5%. In both studied aviaries, the dominating invasion was coccidiosis, with average prevalences of 55.3%. The eggs of nematodes from Capillaria were found in 34.2% of all studied samples. Monoinvasion was present in 31.6% while the mixed invasion of coccidiosis and capillariasis was found in 28.9% cases. Dispersive forms of the parasites were significantly more frequent in the faeces of hens (77.3%) than of cocks (37.5%). No statistically significant differences in invasion extensiveness between the two breeding centres were found. The invasions of both types of parasites in the studied flocks were of a low level (the average OPG was 268.2 while the average EPG of Capillaria sp. was 164.3). The average OPG/EPG values in both breeding centres were similar, which was confirmed by student t-test. Higher values of OPG/EPG were found in samples coming from hens than in those coming from cocks but the differences were insignificant.