Morphological variation of Varroa destructor (Parasitiformes, Varroidae) in different seasons

Varroosis is one of the most dangerous and common diseases of honey bees (Apis mellifera Linnaeus, 1758) worldwide, caused by gamasid mites of the species Varroa destructor Anderson and Trueman, 2000. This external parasite is widespread and adapted to the climate conditions of most countries of the world, and it can infect bees at any life stage. It parasites on worker bees, male and queen bees, larvae and pupae, feeding on their hemolymph and fat bodies, causing lower survival rates and lower density of bee colonies, decreasing the bees’ life span. Here, we studied the specifics of the seasonal variation of female V. destructor mites, obtained from honey bees, by the morphological characters of mites belonging to the summer and winter generations, and their differences were established. Using the methods of multivariate statistics, we found significant differences between the summer (June–July) and winter (October–November) morphotypes of V. destructor mites. There are differences between the seasonal samples by 12 morphological characters of the parasite, namely the width of dorsal shield, width of dorsoventral shield, number of pores on sternal shield, length of tarsus and macrochaeta IV, and distances between setae of gnathosoma. Processing the seasonal samples of mites with discriminant analysis resulted in differences by 11 morphological characters including the length of dorsal shield, number of lancet setae, length and width of genitoventral shield, width of anal shield, number of setae and pores on sternal shield and distance between setae of gnathosoma. In general, the summer females are smaller and elongated compared to winter females, with larger genitoventral shield and shorter legs. The mites of summer and winter generations are adapted to different seasons: the summer mites to the reproductive period, the winter generation to overwintering on bees. The ratio of morphotypes in female V. destructor mites is observed to change during the year, from 20.2% winter morphotype in summer generation to 20.7% summer morphotype in winter mites. Studying the influence of acaricides on the distinguished morphotypes is a promising approach to improve pest control measures against varroosis of honey bees

The state of the immune system of dogs in experimental toxocariasis

The aim of the study was to determine the state of the dogs' immune system in experimental toxocariasis. The work was performed during 2017-2020 at the Department of Parasitology and Ichthyopathology in Stepan Gzhytskyi National University of Veterinary Medicine and Biotechnologies Lviv. The 12 dogs aged 2 to 4 months were used for research studies. Two groups were formed of six animals in each: control and experimental. Puppies of the experimental group (E) were infected with the causative agent of toxocariasis at a dose of 5000 invasive eggs of Toxocara canis per kg of body weight. The control puppies were clinically healthy. At the clinical display of toxocariasis invasion at dogs the cellular, humoral and nonspecific links of the immune system are suppressed and the secondary immunodeficiency comes. Suppression of cellular immunity was accompanied by a decrease in the T- and B-lymphocytes count in the blood of dogs of the (E) group, which indicates the suppression of the lymphoid immune system and a reduction in the resistance of animals. Along with the fall in cellular immunity in infected puppies, suppression of the nonspecific immune system was established, which is manifested by a decline in the phagocytic activity of neutrophils and a decrease in the phagocytic index. Thus, on the 15th and 20th days of the test, the phagocytic activity of neutrophils reduced to 1.6 and 3.9 %, while the phagocytic index – to 5.4 and 6.9 %, respectively. In the study of antimicrobial activity of serum of infected dogs, T. canis found inhibition of bactericidal and lysozyme activity, which reflects the suppression of the physiological state of the humoral immune system of animals with the development of toxocariasis. On the 25th day of the research, a deccline in BABS to 24.0 ± 2.7 %, while in the (C) group of dogs this figure was 30.6 ± 1.9 %. The lowest LABS was on the 25th day of the (E) in animals that were experimentally infected with the pathogen toxocariasis, where compared with the (C) group, this figure decreased by 6.0 %, respectively. The high level of CIC in the serum of dogs infected with T. canis indicates the suppression of the immune system of their body due to the accession of specific antibodies to the products of metabolism of toxocara, which act as antigens

Вплив ліпоінтерсилу та клозаверму А на антиоксидантний статус організму корів за фасціольозу

One of the most prevalent and dangerous helminth infections in large and small ruminants is fasciolosis, which causes significant economic losses in animal husbandry, including reduced milk and meat productivity, deterioration in product quality, and costs associated with treatment and prevention measures. According to the literature, various adverse factors, including fasciolosis, significantly enhance cell reactive oxygen species (ROS) reactions through oxidative stress mechanisms. The study aimed to investigate the impact of the liposomal antioxidants Lipointersil and Clozaverm A on the antioxidant status of cows with experimental fasciolosis. Fifteen 4–5-year-old Black-and-White dairy cows were selected and divided into three groups of five animals each. The cows in the control and experimental groups were experimentally infected with adolescariae. In the first experimental group, cows received intra-muscular injections of Clozaverm A at 0.5 ml per 10 kg of body weight after experimental fasciolosis induction. The second experimental group received the same dose of Clozaverm A along with Lipointersil at a dose of 6 ml per animal. Based on the research conducted, it was found that fasciolosis suppresses the activity of antioxidant defense enzymes in the host liver, evidenced by decreased catalase and superoxide dismutase activity and increased levels of lipid hydroperoxides and TBK-active products in their blood. The administration of Lipointersil and Clozaverm A to cows with experimental fasciolosis improved their antioxidant status. This was accompanied by a 46.7 % increase in superoxide dismutase activity (P < 0.001) and a 30.2% increase in catalase activity (P < 0.001) in their blood. Furthermore, there was a suppression of lipid peroxidation processes indicated by a 31.3 % decrease in lipid hydroperoxide levels (P < 0.001) and an 18.8 % decrease in TBC-active products (P < 0.001).Одним з найбільш поширених і небезпечних гельмінтозів великої та дрібної рогатої худоби є фасціольоз, який завдає значних економічних збитків тваринництву: зниження молочної та м’ясної продуктивності, погіршення якості продуктів, витрати коштів на проведення лікувально-профілактичних заходів. Згідно даних літератури відомо, що за дії на організм різних негативних факторів, в тому числі за фасціольозу, реакції вільнорадикального окиснення у клітинах різко посилюються. Саме тому метою роботи було дослідити вплив ліпосомального антиоксидантного препарату “Ліпоінтерсил” та “Клозаверму А” на антиоксидантний статус організму корів за експериментального фасціольозу. Для дослідів було відібрано 15 корів 4–5-річного віку, чорно-рябої породи, з яких сформовано 3 групи, по п’ять тварин у кожній. Тварини контрольної та обох дослідних груп були експериментально заражені адолескаріями. Коровам першої дослідної групи за експериментального фасціольозу внутрішньом’язово вводили клозаверм А у дозі 0,5 мл препарату на 10 кг маси тіла тварини. Тваринам другої дослідної групи, за експериментального фасціольозу внутрішньом’язово вводили клозаверм А у дозі 0,5 мл препарату на 10 кг маси тіла тварини та ліпоінтерсил у дозі 6 мл препарату на тварину. На основі проведених досліджень встановлено, що фасціоли пригнічують активність ензимів системи антиоксидантного захисту у печінці хазяїв, на що вказує зниження активності каталази та супероксиддисмутази, а також зростання рівня гідроперекисів ліпідів і ТБК–продуктів у їх крові. Застосування ліпоінтерсилу та клозаверму А коровам за експериментального фасціольозу сприяло підвищенню антиоксидантного статусу їх організму, що супроводжувалось підвищенням у їх крові активності супероксиддисмутази на 46,7 % (Р < 0,001) та каталази на 30,2 % (Р < 0,001), а також пригніченням інтенсивності процесів пероксидного окиснення ліпідів, зниженням рівня гідроперекисів ліпідів на 31,3 % (Р < 0,001), ТБК-активних продуктів на 18,8 % (Р < 0,001)

System of antioxidant protection of young cattle under cadmium load

It is known that free radical oxidation of lipids is an essential stage in the influence of heavy metals on the animal body. That is why the work aimed to investigate the indicators of the antioxidant system in young cattle under conditions of cadmium loading. For research, 15 clinically healthy six-month-old bulls of the black and spotted breed were selected, from which 3 groups of five animals were formed. The animals in the control group were on a regular diet. The animals of the experimental groups with compound feed were fed cadmium chloride in doses of 0.03 and 0.05 mg/kg of body weight. Feeding young cattle with cadmium chloride feed caused a decrease in the activity of the enzyme system of antioxidant protection of their body. These changes are confirmed by a decrease in their blood activity of superoxide dismutase by 31 %, catalase by 13.4 %, glutathione peroxidase by 23.2 %, glutathione reductase by 22.2 %, and glucose-6-phosphate dehydrogenase by 32.4 %, respectively. A decrease in the level of indicators of the non-enzymatic link of the system of antioxidant protection of the body of young cattle under cadmium load was also established, where, accordingly, a decrease in the content of reduced glutathione was established – by 10.4 %, selenium – by 14.8 %, vitamin A – by 31.3%, of vitamin E – by 30.8% in their blood compared to the control. It is worth noting that on the sixteenth and twenty-fourth days of the experiment, the lowest value of the enzymatic and non-enzymatic links of the antioxidant protection systems of young cattle under conditions of cadmium loading was observed. In the future, a practical scheme for preventing cadmium toxicosis in young cattle by studying indicators of the antioxidant system is planned