The purpose of the research is to study the parasite fauna of the common frog (Rana temporaria Linnaeus, 1758) inhabiting the vicinity of the Visim Nature Biosphere Reserve.Materials and methods. The species composition, dominance structure and endoparasite infection of 32 individuals of R. temporaria caught along the banks of the upper reaches of the Sulem Riverwere assessed according to the following indicators: the prevalence and intensity of infection and abundance index.Results and discussion. The species composition of parasites in a common frog from the vicinity of the Visim Nature Biosphere Reserve is presented for the first time. Five species of macroparasites have been identified, classified as Nematoda: Oswaldocruzia filiformis (Goeze, 1782), Neoraillietnema praeputiale (Skrjabin, 1916), Cosmocerca ornata (Dujardin, 1845), Rhabdias bufonis (Schrank, 1788) and as Platyhelminthes: Haplometra cylindracea (Zeder, 1800). One species of endosymbiotic protozoa of Chromista, Opalina ranarum was recorded (Purkinje et Valentin, 1835). The prevalence of the infection of common frogs by helminths reaches 100%, the abundance index is 11.06, and protozoa is 93.8% and 62.16, respectively. Nematodes O. filiformis (the prevalence of infection 96.9%, and abundance index 7.97) and R. bufonis (the prevalence of infection 46.9%, abundance index 2.28) predominate. It was shown that nematode N. praeputiale was not found in the parasitocenosis of immature amphibians, and trematode H. cylindracea was not found in adult animals. The proportion of O. filiformis and C. ornata increases with age in common frogs. It was found that the animals of the July population are infected with nematode R. bufonis largely. Regardless of the age of R. temporaria, the probability of colonization by O. ranarum in spring will be higher.

The aim of the work was to rank statistical models for assessing the contribution of a number of factors that determine the epizootic situation on natural-focal infectious diseases in the communities of non-synanthropic small mammals (SM) in the forests of Ekaterinburg.Materials and methods. The SM survey was carried out for three years in the summer-autumn period. The animals were caught with snap tpaps on a standard bread bait, 9705 trap-nights were worked out. To identify infections (hemorrhagic fever with renal syndrome, tularemia, leptospirosis, yersiniosis, pseudotuberculosis), 333 SM specimens (rodents and shrews of six species) were used, randomly taken from the general sample. To determine the pathogens, the methods of enzyme immunoassay and polymerase chain reaction were used. The cumulative infection rate of small mammals with all studied natural-focal infections was evaluated. Statistical data processing was carried out from the standpoint of a multi-model approach. The selection of models was performed using the Akaike information criterion with the calculation of the sum of the weights of the models based on their full spectrum (SW).Results and discussion. Carriers of all of the mentioned above infections, except for pseudotuberculosis, have been identified in the forest parks of Ekaterinburg. According to the ranking, the model with three predictors received the highest weight: species, year, and the abundance of SM of the previous year in a particular habitat. The most significant predictors for the full spectrum of models are the year (SW=1), species (SW=0.6), abundance of animals in the current and previous year (SW=0.48). The distribution of positive samples by species of small mammals corresponded to their ranking by abundance in the community. The influence of the factors “season” (summer or autumn) and “area” (place of capture of animals) turned out to be insignificant on the scale of the studies (SW = 0.3 and 0.16, respectively). The percentage of infected samples in total for all infections varied significantly by location and year (0–60%). The possible significance of unaccounted factors is discussed: landscape features and the mode of using forest parks, dispersal of small mammals. The conclusion is made about the usefulness of the multi-model approach in the analysis of the data from epizootiological studies.

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Опубликовано Российским государственным педагогическим университетом им. А. И. Герцена. Открытый доступ на условиях лицензии CC BY-NC 4.0.Аннотация. Изучали потенциальные проблемы разработанного ранее рекогносцировочного гуманного метода оценки обилия мелких млекопитающих с помощью пластиковых бутылок. Первой задачей работы было определить, какой из двух вариантов интервала между бутылками на трансекте (пять или десять метров) подвержен большей погрешности из-за особей, посещающих более одной бутылки за сутки. Вторая задача -сравнить избирательность бутылок и давилок по отношению к видовой и половозрастной структуре сообществ. Использовалось точечное чередующееся мечение с помощью приманки на основе овса с родамином B или тетрациклином. Приманку в пластиковых бутылках раскладывали на трансектах с интервалом пять метров или десять метров. Спустя сутки животных отлавливали давилками на стандартную хлебную приманку и проводили поиск маркеров. Особи, имевшие одновременно родаминовую и тетрациклиновую метку, считались посетившими более одной бутылки за сутки. Статистически значимой разницы между двумя способами расположения бутылок по доле особей с двойной меткой не выявлено (5,3% при интервале десять метров и 6,2% при интервале пять метров). Полнота мечения сообщества при пятиметровом интервале была выше (max = 77%), чем при десятиметровом (max = 46%), что может повышать точность оценки обилия. Избирательность бутылок и давилок по отношению к виду, полу и возрасту грызунов не отличалась. Полученные результаты подтверждают правомерность пересчета индексов обилия, полученных бутылочным методом, в относительную численность. Показано, что родамин В является более эффективным биомаркером, чем тетрациклин.

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