Pavlo M. Skliarov
@dsau.dp.ua
Department of Veterinary Surgery and Reproduction / Faculty of Veterinary Medicine
Dnipro State Agrarian and Economics University
EDUCATION
Kharkiv Zooveterinary Institute
RESEARCH INTERESTS
Veterinary reproductive medicine, obstetrics, gynecology, andrology, mastology, neonatology
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Roman Mylosyvyi, Pavlo Skliarov, Olena Izhboldina, Оleksandr Chernenko, Мaryna Lieshchova, Bogdan Gutyj, Oleh Marenkov, and Djallal Eddine Rahmoun
Croatian Veterinary Institute, Zagreb
The identification of cows and heifers in heat and their timely artificial insemination (AI) is an important issue for large dairy units. The objective of the research was to study the efficiency of insemination of oestrous Brown Swiss heifers using am automated heat detection system (AHD) compared to heat detection by visual observation (VO). The AHD system application increased the fertility of heifers by 8.9% when using conventional semen (unsexed) and by 14.4% using sexed semen. The number of services per conception when using sexed semen decreased from 3.7±1.08 with VO to 2.4±0.68 with AHD. Two-factor analysis of variance showed that an 89% effect of managerial decisions such as the detection of heifers in heat by means of AHD and the use of sexed semen on the efficiency of insemination. This study showed that professional breeders and veterinarians should pay particular attention to AI management when making these managerial decisions in large dairy units.
Carlos C. Pérez-Marín, David Cano, Francisco A. Arrebola, Valerii H. Petrusha, Pavlo M. Skliarov, José A. Entrenas, and Dolores C. Pérez-Marín
MDPI AG
Failure of passive immunity transfer is one of the main causes of increased susceptibility to infectious agents in newborn kids. To ensure successful transfer of passive immunity, kids need to be fed high-quality colostrum, containing an adequate concentration of IgG. This work evaluated the quality of colostrum obtained in the first 3 days postpartum from Malagueña dairy goats. The IgG concentration in colostrum was measured using an ELISA as a reference method, and it was estimated by optical refractometer. Colostrum composition in terms of fat and protein was also determined. The mean concentration of IgG was 36.6 ± 2.3 mg/mL, 22.4 ± 1.5 mg/mL and 8.4 ± 1.0 mg/mL on days 1, 2 and 3 after parturition, respectively. Brix values obtained using the optical refractometer were 23.2%, 18.6% and 14.1% for days 1, 2 and 3, respectively. In this population, 89% of goats produced high-quality colostrum with IgG concentrations of >20 mg/mL on the day of parturition, but this percentage declined dramatically over the following 2 days. The quality of the fresh colostrum estimated with the optical refractometer was positively correlated with those obtained using ELISA (r = 0.607, p = 0.001). This study highlights the importance of feeding first-day colostrum to newborn kids and demonstrates that the optical Brix refractometer is suitable for the on-farm estimation of IgG content in colostrum.
Vsevolod Koshevoy, Svitlana Naumenko, Pavlo Skliarov, Kateryna Syniahovska, Galina Vikulina, Volodymyr Klochkov, and Svitlana Yefimova
Scienceline Publication
Oxidative stress as a leading factor of male infertility requires correction with modern pharmacological agents, particularly redox-active nanoparticles, to improve sperm quality and hormonal balance. The current experimental study aimed to investigate the effect of orthovanadate nanoparticles of rare earth elements, particularly Gadolinium, with pronounced redox properties on the reproductive function of male rabbits under oxidative stress. A total of 36 mature male Hyla rabbits were divided into three groups of intact control (n = 12) and two experimental groups, including rabbits ubder oxidative stress (n = 12), induced by the introduction of tert-Butyl hydroperoxide, and those under oxidative stress plus hydrosol of gadolinium orthovanadate nanoparticles (NPs, n = 12) intake for 14 days. There were four rabbits per three replicates in each group. Animals of all groups were kept on the same diet and had free access to water. The use of NPs led to an improvement in sperm quality indicators. There was an improvement in motility and ejaculate volume indicators (by 14.6% and 39.2%, respectively), a reduction of the content of morphologically abnormal sperm by 26.7%; normalization of sex hormones, an increase in the level of total testosterone (by 113%) with a decrease in 17-β-estradiol (by 16.5%). This sex hormones improvement led to an increase in the androgen saturation of the rabbit’s body (free androgen index at the end of the experiment was 36.5%). The obtained changes were accompanied by a decrease in the oxidative load, as evidenced by a reduced content of diene conjugates and thio-barbituric acid-reactive compounds in the blood serum of rabbits by 30.4% and 26.8%, compared to the control. At the same time, there was an increase in the antioxidant potential, especially its glutathione link – the activity of glutathione peroxidase and glutathione reductase (by 42.5% and 34.2%, respectively), and the content of reduced glutathione increased by 62.3%, compared to the indicators before the introduction of NPs. The results of the study confirmed the effectiveness of using gadolinium orthovanadate NPs to correct the reproductive function of males under oxidative stress.
Pavlo Skliarov, Serhiy Fedorenko, Svitlana Naumenko, Oleksandr Onyshchenko, Alina Pasternak, Liliya Roman, Maryna Lieshchova, Dmytro Bilyi, and Olga Bobrytska
Scienceline Publication
Animal reproduction is one of the main factors limiting the efficiency of livestock production. Its optimal level is possibly achieved when certain conditions are created for animals. As reproduction is a complex reflex process depending on neuroendocrine regulatory mechanisms, the character and strength of stimuli, which, in turn, is due to a number of factors. Under normal conditions, the body of animals is affected by many different factors, which are appropriately transformed and specified by positive or negative reactions. Inhibitory factors include air pool, saturated with harmful substances and gases, ionizing radiation, poor water quality along with altered redox properties, hypokinesia combined with poor unbalanced feeding, systematic chronic stress, presence of toxic substances in feed, and the deficiency of vitamins and other bioantioxidants in feed or their excessive spending. Of the wide range of genetic and paratypic factors of negative impacts on reproductive capacity, the most common one is alimentary, which causes impaired reproductive function due to deficiencies in the rules, regulations, and feeding regime of animals. In particular, the alimentary can be associated with both general malnutrition (starvation) and overfeeding (obesity). However, the alimentary form of infertility mostly occurs due to low-quality diets when the diet lacks vital components (mainly vitamins, macro-, and micronutrients) or the quantitative ratios of the ingredients are violated. This is possible even if the total nutritional value of the diet meets the established requirements for the physiological needs of the body. Vitamins, micro-, and macronutrients are ecologically deficient factors of disturbance of animal reproductive function, the influence of which is observed on all processes of reproduction, from fertilization to the postpartum period and the preservation of young animals. The pathogenesis of their insufficiency is associated with the violation of steroido-, gameto-, and embryogenesis and the emergence of ante-, intra-, neo- and postnatal pathologies, respectively. Therefore, treatments and prevention measures should be aimed at providing animals with biologically complete balanced feeding and replenishment of the body with vitamins and minerals. However, all these issues remain incompletely studied and need further research.
M. S. Kovalenko, D. D. Bilyi, P. M. Skliarov, S. N. Maslikov, N. I. Suslova, T. L. Spitsyna, and I. D. Yevtushenko
Oles Honchar Dnipropetrovsk National University
Due to relevance of the problem, prediction of biological behaviour of neoplasias in mammary glands of dogs requires using contemporary approaches to the study, first of all, of ways of dissemination of tumour cells. One of them is studying the mechanisms of migration of cancer cells out of the neoplasm tissues with further dissemination and development of metastatic sites in the regional lymphatic nodes and remote tissues. We studied the survival period of bitches with tumours of the mammary glands following regional or unilateral mastectomy. Among malignant mammary tumours in bitches, the most often diagnosed were single tumours (57.5%), which histologically were classified to carcinomas – ductal (26.9%) and mixed type (21.9%). Probability of intratumoral invasion to blood vessels equaled 12.0%, to lymph vessels – 7.8%, lymph nodes – 12.8%. It depends on the histological type of the tumour, the most aggressive potentially being сomedocarcinoma, tubulopapillary carcinoma and ductal carcinoma. Parameters of life expectancy and survival level after mastectomy depend on clinical stage of the disease (increase in the stage from the first to the third was characterized by decrease from 12.8 ± 9.5 to 9.4 ± 7.8 months), presence of angio/lymphatic invasions, presence of angiolymphatic invasion, but had no correlation with the size of the tumours. An important predictor of tumour-related death of dogs suffering neoplasias of the mammary glands is index vet-NPI, which has significant correlation with the clinical stage according to Owen and median survival. In particular, median survival in patients with the index lower than 4 exceeded the corresponding values in dogs with the index above 4 by 1.3 times. A promising direction of further research would be studying biological mechanisms of development of tumour emboli in the blood and lymph vessels, metastatic sites in lymph nodes, and also determining their role in pathogenesis of canine mammary tumours.
Pavlo Skliarov, Serhiy Fedorenko, Svitlana Naumenko, Vsevolod Koshevoy, and Kateryna Pelyh
Scientific Journals Publishing House
Modern conditions of practical veterinary medicine require the use of effective and safe drugs. Along with the already known and common medicines, the search for new drugs which are harmless for the body and have the physiological direction of action is still required. In recent years, the attention to the use of phyto- and tissue-derived drugs increased. However, the problem of their use is insufficiently studied – many aspects of their clinical use require further development, expansion of the spectrum of used medicinal plants, study, and implementation into veterinary practice. Therefore, the purpose of this work was to develop a comprehensive vitamin-hormone drugs based on phyto- and tissue medicines for the treatment and prevention of reproductive abnormalities in animals. Based on the information on the etiopathogenesis of disorders of reproductive function indicators: homeostasis, reducing of the concentration of hormones (estrogen or progesterone), changes in the morphofunctional state of endocrine (pituitary, thyroid, and adrenal gland) and reproductive (ovaries) organs, the application of vitamin-hormone drugs in veterinary medicine is scientifically sound. Drugs in terms of pathogenetic therapy can optimise homeostasis, hormone concentrations, stimulate rehabilitation processes in the regulatory organs of reproductive function (pituitary, adrenal, and thyroid) and reproductive organs (ovaries), which, in turn, contributes to the normalisation of follicles which are a prerequisite for the full reproductive capacity of females. Vitamin-hormonal medicines of herbal and tissue origin were developed, with high efficiency for the treatment and prevention of reproductive pathologies of various species of animals, providing the stimulation of reproductive function (estrus signs) for therapy of females with gonadopathies (“Carafest”, “Caplaestrol” and “Caplagonìn”) and males (display of sexual reflexes and sperm quality) for reproductive activity dysfunction (“Carafand”), increase in the viability of the newborn (increasing the number of lambs and goatlings with satisfactory clinical condition with a high-growth potential, reduce in their morbidity and lethality), preventing the incidence of ìntra- and postnatal (labor hypofunction, diseases of post-labor period) pathology (“Carafest”, and “Caplaestrol”)
Vsevolod Koshevoy, Svitlana Naumenko, Pavlo Skliarov, Serhiy Fedorenko, and Lidia Kostyshyn
Scientific Journals Publishing House
The basis of the pathogenesis of male infertility is the processes of peroxide oxidation of biological substrates, especially lipids and proteins. By destroying the sperm membrane, toxic peroxidation products reduce its motility and ability to fertilize the egg, which is determined by a decrease in the number of motile sperm in the ejaculate. These changes lead to complete or partial male infertility. The authors of the review found that is accompanied by a damaging effect on the structural and functional activity of the gonads and is manifested, in particular, by an imbalance in the hormonal background of the male body. Similar effects are characteristic of an increase in the content of reactive Nitrogen species and its metabolites, which cause nitrosative stress, which is also the cause of male hypofertility and is inseparable from the state of oxidative stress. In scientific work it is determined that the accumulation of harmful peroxidation products leads to damage and destruction of sperm DNA, reduced activity of acrosomal enzymes and mitochondrial potential of sperm, reduced overall antioxidant activity. This makes it impossible for an adequate response of the body. Multi component antioxidant defense system resists stress. It is represented by enzymatic and non-enzymatic links, which can neutralize harmful radicals and peroxidation products. It contributes to the full manifestation of reproductive function. The presence of powerful antioxidant properties of catalase, superoxide dismutase, and enzymes of the thiol-disulfide system, which form the enzymatic system of antioxidant protection, as well as selenium, zinc, copper, other trace elements, retinol, tocopherol, ascorbic acid, and vitamins as parts of the non-enzymatic system is shown. The efficiency of registration is substantiated thin biochemical shift detectors or complex methods, such as total antioxidant status of sperm or sperm plasma, mitochondrial membrane potential, etc along with simple markers of oxidative stress, such as diene conjugates, malonic dialdehyde, and metabolites of the Nitrogen Oxide cycle. Given the leading role of oxidative stress in the development of male hypofertility, the prospect of further research is the search for modern means for correction, especially among substances with pronounced redox activity
Pavlo SKLIAROV, Carlos PÉREZ, Valerii PETRUSHA, Sergij FEDORENKO, and Dmytro BILYI
Journal of Central European Agriculture
Different methods for oestrus induction and synchronization in domestic small ruminants have been developed. Seasonality and female’s status are important factors for choosing the most appropriate treatment. In the case of females during breeding season, prostaglandins can be used since functional corpus luteum must be present in the ovaries, while during non-breeding season females should be treated with progesterone-based treatments, accompanied by equine chorionic gonadotrophin (eCG), releasing hormones and other compounds. Significant spread of oestrus synchronization during and after the breeding season has been achieved by the use of intravaginal sponges impregnated with synthetic analogues of progesterone. However, the effect of hormonal drugs on the female reproductive system may manifest differently depending on the initial functional state of reproductive organs and the hormonal status, and negative consequences can be observed when drugs are wrongly administered. In addition, insufficient knowledge about the patterns of change in the reactivity of the nervous sexual centers and the corresponding reactions of the body to the administration of hormones reduces their effectiveness, which limits the widespread use. In general, the induction and synchronization of oestrus in small ruminants is an currently important direction of scientific research and an urgent problem of sheep and goat breeding, but the proposed methods require further improvement by reducing the costand increasing biosecurity and predictability of the result.
A. V. Oliyar, P. M. Skliarov, D. M. Masiuk, D. D. Bilyi, V. V. Logvinova, and M. A. Lieshchova
Oles Honchar Dnipropetrovsk National University
Identifying and eliminating factors that interfere with the nutrient absorption from feed is essential for successful poultry rearing. The nutritional value of feed mixtures used in the poultry industry can be increased by the use of enzyme supplements, in particular β-mannanase (Hemicell), which breaks down the anti-nutrients β-mannans that are present in significant quantities in soy products. For the study, two groups of 50 broiler chickens were formed. In the control group a standard feed mixture from cereals was used, particularly soybeans, and in the experimental group 0.05% β-mannanase enzyme supplement (Hemicell) in addition to the compound feed was used. Production indicators were established (average daily gain, survival rate, feed costs). On the 15th, 25th and 42nd days of rearing, lymphatic organs (cloacal bursa and spleen) were collected from seven chickens of each group, followed by macro, microscopic and morphometric evaluation. It was found that the addition of an enzyme supplement promotes an increase in the production indicators of poultry rearing, reduces feed use, does not affect the macroscopic characteristics of the lymphatic organs. β-mannanase (Hemicell) contributes to the maintenance of an active morphofunctional state of the cloacal bursa and spleen during the entire period of poultry rearing. This was manifested by high indices of the absolute and relative organ masses, a moderate development degree of tissue components and cloacal bursa histological structures (number, shape and average length of lymphatic nodules, density of lymphocytes in the cortex and medulla) and spleen (number and diameter of lymphatic nodules and periarterioal lymphatic sheaths). In the control group, at all stages of rearing, the morphofunctional state of the bursa was found to be lower and signs of immunosuppression were revealed by the end of the rearing period (a sharp decline in the bursa absolute mass, organ mass index, a decrease in the average length of nodules, change in their shape, thinned cortical layer and delymphotisation). The morphofunctional state of the spleen of chickens from the control group remained high throughout the entire study period. So use of the β-mannanase enzyme supplement (Hemicell) while rearing broiler chickens not only increased the efficiency of their rearing but also contributed to maintaining a high morphological and functional state of the cloacal bursa.
P. M. Skliarov, S. Y. Fedorenko, S. V. Naumenko, O. V. Onischenko, and K. О. Holda
Oles Honchar Dnipropetrovsk National University
Infertility is widespread for all species of animals and causes significant economic losses to livestock due to the loss and shortage of offspring, their reduced viability and, consequently, increased morbidity and mortality. Alimentary-deficiency factors are among the commonest causes of infertility, from which A-vitamin deficiency should be singled out. The precursor of vitamin A in the body is carotene, which is an unstable compound which is easily destroyed even under the influence of moderate factors of influence, in connection with which its deficiency is global, especially at the end of the winter – stall period of keeping animals. Accordingly it is the leading etiological factor of retinol deficiency infertility. As a result, the body has two negatives that act in parallel: carotene / vitamin A deficiency adversely affects the organs, the constituent and major functional unit of which is the secretory epithelial cell, and the free radical oxides formed in high concentration are extremely effective in destroying the cells, weakening antioxidant protection. Vitamin A has a significant effect on the reproductive function of animals both directly and indirectly. It is necessary to ensure the structure and functioning of the epithelial tissues of the organs of regulation and performance of sexual function, and therefore the physiological development of the fetus and the course of pregnancy, parturition and postpartum period, ovo- and spermiogenesis, the manifestation of sexual reflexes. Instead, its deficiency underlies the etiology and pathogenesis of retinol deficiency infertility of animals, causing changes in individual indices of homeostasis and prooxidate-antioxidant system, morphostructure of the reproductive and endocrine organs, hormonal status, sperm quality and reproductive function. The consequence is the emergence and development of gynecological, andrological, mammological and perinatal (ante-, intra-, post- and neo-) pathologies. At the same time, the addition of carotene or retinol to the diets of animals or their oral administration in cases of deficiency of vitamin A prevents impaired reproductive function. The study of the features of the etiopathogenesis of retinol deficiency infertility of animals allows programs of complex diagnostics, therapy and prevention to be developed which provide determination of carotene and vitamin A content and replenishment of the organism in cases of their deficiency.