Today one of the important problems in poultry farming and bird keeping both in homesteads and on farms is the spread of endoparasites, which cause a significant decrease in productivity and significant economic damage. Raillietinosis and daveniosis are natural focal tape helminthiases that parasitize in the small intestine of poultry. The research on chicken cestodiasis was carried out on poultry farms in the south of Odessa Region of Ukraine during 2017 and 2019. 4219 chickens of different age groups were examined, which used walking areas, with 1965 chickens – in 2017 and 2254 – in 2019. To assess the wet and dry periods with daily average temperatures above 10 °C, that is the period of active vegetation, the Selyaninov hydrothermal coefficient (SHC) was used (1937), according to which the spread of chicken cestodiasis was determined. In the south of Odessa Region, the moderate and severe period increased from four to seven months, at which the hydrothermal coefficient amounted to 0.4–0.8. The period of sufficient moisture at a hydrothermal coefficient of 1.0–1.5 decreased from three months of 2017 to two months of 2019 and the hydrothermal coefficient was not calculated for five and three months, respectively. In 2017, the hatching of cestode eggs with bird manure was recorded for nine months: from March (10.1%) to November (5.8%) with high rates in June (27.2%) and September (37.1%), while in 2019, cestode eggs were recorded in February (12.7%) and up to December (2.4%), that is, for 11 months, with the highest rates in May (41.8%) and September (43.9%). The species composition of chicken cestodes is represented by four species: Raillietina echinobothrida (74.2%), which dominates due to a longer low hydrothermal coefficient, as well as R. tetragona (9.8%), R. cesticillus (10.8%) and Davainea proglottina (5.2%). The invasion of ants with cysticercoid R. echinobothrida in 2017 amounted to 19.6%, and in 2019 – 25.9% with an intensity of 1 to 4 specimens.

Penetration of jackal, typical representative of Asia Minor-Balkan group, genus Canis aureus into the territory of the Northwest Black Sea coast - has become a rather unexpected phenomenon and led to environmental, zoogeographical and epizootic issues. The last one may lead to the development of potentially dangerous epizootic processes, the assessment of the threat and possible consequences require systematic researches. The purpose of this work was to study the ecological and epizootic role of Canis aureus in the territory of the Northwest Black Sea coast. The investigations concerning epizootic status of jackal were carried out during 2014–2018 in the territory of Odesa and Mykolayiv Regions with means of laboratory control samples of the materials which were selected and taken from hunters. The results of researches have shown that there is a complete, self-regulating and rather dense population of C. aureus in this region, it does not lose the rate of intensive reproduction and has a clearly expressed western line of genus penetration. In the process of migratory settlement, jackal demonstrates clear and static dependences on humidified and hydro morphed landscapes. When the bodies of animals were observed, we could find the presence of ticks and several types of fleas that could act as a biological transmission objects in the circles of spontaneous circulation of naturally occurring zoonotic pathogens, ensuring their inter-species migration and short-term reservation. According to the results of laboratory examinations of 9 samples of jackals’ blood serum, the presence of antibodies to the causative agent of erysipelas was determined in 5 (55.5%) cases. In response to a single brucellosis antigen The specific antibodies were not found in the reaction with single brucellosis antigen. The investigations on the presence of leptospirosis were carried out with test strains of 9 serogroups. Specific anti-lepidopteran antibodies were found in all investigated serum samples. The predominance of antibodies to the Grippotyphosa, Hebdomadis, Sejroe, Bataviae serogroups, mice field rodents are their host, indicates the trophic nature of antigenic contacts. The new species for Ukraine – jackal Cainis aureus carries a significant potential epizootic threat as a host and carrier of pathogens natural-focal zoonotic infections and invasions, the most dangerous among them is rabies.

Pigeons are closely related to human life and are both a source of food and object for hobbies and sports. Parasitic diseases of birds are the main reason for their growth retardation, reduced productivity and viability. The article presents the results of studying the prevalence of trichomonosis, cestodes and nematodes among the population of wild and domestic pigeons in the south of Ukraine. According to the results of the conducted researches it is established that in the south of Ukraine endoparasitoses of domestic and wild pigeons are quite widespread, and all species of this bird are carriers of Trichomonas gallinae. At the same time, the highest rate of Trichomonas infection was recorded in Columba palambus and C. livia domestica, and the overall infestation of males is higher by 4.4% compared to females. It was determined that domestic pigeons C. livia domestica were infested with trichomonosis (27.5%) and nematodes (Ascaridia columbae, 57.1%), C. palambus – trichomonosis (32.1%) and cestodes (Raillietina spp., 82.4%), Streptopelia turtur – cestodes (Raillietina spp., 12.5%) and S. decaocto – cestodes (Raillietina spp., 71.4%) and nematodes (Heterakis gallinarum, A. columbae – 33.3% and 44.4% respectively). The overall rate of infestation of pigeons with cestodes was 28.4% and the incidence in males was higher by 3.9% compared to females. It was found that the most common species among pigeon cestodes is Raillietina spp. In addition, 22.9% of pigeons are carriers of nematodes (H. gallinarum, A. columbae and Capillaria spp.). Continuous monitoring of pigeon parasites is necessary because they, in most cases, come into contact with other species of poultry and are a source of general invasion. In terms of further research, it would be promising to study the prevalence of helminthic infestation among wild migratory birds.

One of the main tasks of ecological parasitology at the present stage is to establish patterns of spread of invasive diseases of animals in the environment through a thorough epidemiological examination, as well as to determine the main directions and factors of spread of parasites in Ukraine. Among the many pathogens, endoparasites play a major role in a number of diseases in rabbits with increased morbidity and mortality. In the body of both wild and domestic rabbits several species of parasites that form a parasitocenosis can be localized. The latter have a pathogenic effect on organs and tissues, leading to reduced weight gain, premature slaughter and even mortality. The prevalence of endoparasitoses was studied in weaned rabbits 60 days of age, 120 days of age at fattening, 180 days of age – mating age and adults of 320 days of age to determine the extensiveness and intensity of the dominant invasion. A total of 720 head was studied, 180 animals from each age group. Three species of nematodes were recorded in the rabbits: Trichostrongylus retortaeformis (Zeder, 1800), Nematodirus leporis (Ransom, 1907) and Passalurus ambiguus (Rudolphi, 1819); the cestode Taenia pisiformis (Bloch, 1780); three species of Emeria: Eimeria stiedae (Lindermann, 1865), which parasitizes in the bile ducts of the liver and gallbladder, E. magna (Perard, 1925) and E. media (Kessel, 1929) – in the epithelial cells of the intestine. The prevalence of the infestation depends on the age of the animals. According to the data obtained, eimeriosis was one of the main parasitic diseases of the rabbits. Dominant invasions of Eimeria in the intestines of 60-day-old rabbits were found in the studied animals, their extensiveness reached 19.4%, while the spread of hepatic Eimeria was registered in 13.3% of the examined rabbits. The total infestation of weaned rabbits with helminths was 22.2%, in rabbits for fattening – 26.7%, and in rabbits of mating age and adults – 20.0% and 20.6%, respectively. Global climate change will change the distribution and dynamics of soil-borne helminthiases, but host immunity may also affect host-parasite interactions. Subsequent studies will be aimed at elucidating the effect of mono and mixed invasions on the body of rabbits. Updated data on helminthiasis will expand the screening strategy to maintain rabbit health and reduce economic losses.

The article presents the data of a preclinical test of a means for the treatment of cysticercosis in rabbits by intra-gastric administration to white mice. Cysticercus pisiformis is a disease caused by ingestion of eggs of Taenia pisiformis in food or water, a tapeworm that parasitizes the small intestine of dogs and other carnivores. As a result of the invasion, the body loses its ability to fully function, the resistance of the immune system to infectious diseases decreases. In order to avoid the spread of the disease, it is necessary to make a timely diagnosis. The obtained data can be used to take the necessary measures against infestations and are important to prevent the selective use of anti-parasitic agents, which can lead to anthelmintic resistance. The purpose of the work was to determine the parameters of chronic toxicity of the developed complex anti-parasitic agent for the treatment of rabbits for cysticercosis on white mice under experimental conditions. The animals of the experimental groups were given an aqueous mixture of 0.0002 dm3 of the drug containing the following doses of the drug daily for 12 days: 1/100 DL50 ‒ 16.80 mg/kg (I group); 1/50 DL50 ‒ 33.58 mg/kg (II group); 1/25 DL50 ‒ 67.18 mg/kg (III group). On the next day after the last administration of the drug, on mice, under the condition of light ether narcosis, blood samples were taken for morphological and biochemical studies. The agent for the treatment of cysticercosis in rabbits, at doses of 1/50 DL50 and 1/25 DL50, resulted in a slight decrease in hemoglobin content and erythrocyte count compared to the control, but it did not suppress bone marrow erythropoiesis in laboratory animals. A decrease in the number of lymphocytes and a slight increase in the level of neutrophils were recorded, which indicates the irritating effect of increased doses of the active substance of the drug. According to the classification of chemical substances by degree of danger (DST 12.1.007–76), it belongs to the class of "moderately toxic substances".