Mykola Zhelavskyi - Profile on Academia.edu (original) (raw)

articles by Mykola Zhelavskyi

The immune system of animals plays an important role in the homeostasis system. The aim of the st... more The immune system of animals plays an important role in the homeostasis system. The aim of the study was to detect apoptosis of immune cells in the peripheral blood stream at different periods of lactation in cows. The investigation of the immune defense of cows was conducted during various lactation periods: early (3-5 days), mid (90-150 days), and late (drying off -5-7 days; dry period -12-20 days) periods of mammary gland function. The highest intensity of apoptosis was observed in neutrophils and monocytes during the mid-lactation period. The highest intensity of apoptosis is observed in phagocytic cells during the colostrum secretion period and mammary gland involution. The study of physiological constants of blood cell apoptosis will serve as a basis for developing informative methods of mastitis diagnosis in cows and implementing effective treatment measures. The findings obtained from this research are valuable for practical veterinarians and from a public health perspective.

Pregnancy triggers a series of complex interactions within the body, involving both the immune sy... more Pregnancy triggers a series of complex interactions within the body, involving both the immune system and metabolic processes. In the case of pregnant cows, these mechanisms are essential for supporting the developing fetus and maintaining the overall health of the mother. The aim of the work was to study the hematological, biochemical, and immunological parameters of cows at different periods of pregnancy. Research was conducted on cows (Bos Taurus) of the Ukrainian Black-and-White dairy breed. Groups were formed based on the principle of analogs. The research was carried out using the methodology of group-period experiments. The control group consisted of non-pregnant cows. The first observation period was conducted on pregnant cows with confirmed pregnancy (30 days). The second observation period was carried out at 90 days of pregnancy, the third at 180 days of gestation, and the fourth at 270 days. Laboratory studies included immunological research conducted in the specialized laboratory of immunology for reproduction animals. The first notable observation was the gradual increase in the population of CD 3+ lymphocytes from the beginning of gestation, which remained stable until the 90th day of pregnancy and then gradually decreased. The population of B cell immune cells CD 22+ had its peculiarities: dynamic and stable growth from the start of pregnancy until the middle of the second trimester (180 days), followed by a gradual decrease until the onset of labor. The redistribution of T and B lymphocytes occurred with dynamic fluctuations in the number of undifferentiated 0-lymphocytes. The processes of transformation and adaptation of homeostasis affected both enzyme activity and indicators of mineral metabolism. Thus, from the beginning of pregnancy (from the 30th day of gestation), the experimental cows showed a significant increase in alkaline phosphatase activity (P < 0.05), alanine aminotransferase (P < 0.05), and aspartate aminotransferase activity (P < 0.05). During the pregnancy of cows, body changes occur. From the early period of gestation throughout the entire period of embryogenesis, changes in the system of hematopoiesis, alterations in the activity of enzymes, exchange of Ca and P, accompanied by changes in immunological reactions take place. These processes are adaptive and ensure the maintenance of the homeostasis system. The perspective of further research will aim at studying changes in immunological and biochemical parameters during physiological pregnancy and when it is complicated.

Feline inflammatory aural polyps are abnormal growths that can occur in the ear canals of cats, p... more Feline inflammatory aural polyps are abnormal growths that can occur in the ear canals of cats, particularly in the middle ear. These polyps are frequently linked to persistent inflammation and can result in a range of ear-related complicated pathologies. The etiology is multifactorial. The purpose of the research was to study the cytology of an inflammatory polyp in a cat and to study the role of neutrophils and their mechanisms on the formation of extracellular protective traps by neutrophils (NETs). A 4-year-old, female spayed, Scottish fold cat, weighing 3.5 kg sent to a veterinary clinic (Mirra-Vet, Kyiv, Ukraine). Clinical, otoscopic methods, and laboratory methods of cytological diagnostics were used for the research. At the onset of the clinical investigation, exudate discharge from the ear and a painful response were observed. Upon detailed otoscopy, a polyp in the ear canal was diagnosed. An increase in the number of leukocytes (23.2×10 9 /L), their absolute content, and an increase in the percentage of neutrophils (48.2 %) in the leukogram. Assessing the capacity of neutrophils to generate NETs (Neutrophil Extracellular Traps) was determined after samples were collected using a cytologic brush. Cytological analysis of samples from the inter-tragic incisure area highlighted a significant presence of neutrophils, forming extracellular protective traps. The results revealed free NETs in separate areas of the slides. The findings indicated the formation of cooperative groups among neutrophils, other phagocytes, and epithelial cells, along with slender nuclear streaks. During the treatment (Otoflox, 2 drops per ear), the inflammatory reaction disappears, polyp size decreases, exudative reactions decrease, and neutrophil activity decreases. After 3 days of treatment, the animal's condition improved. The ear was clean without sulfur and lesions. The complete treatment course spanned 7 days. During the treatment, the inflammatory reaction disappeared, polyp size decreased, exudative reactions decreased, and neutrophil activity decreased. Experimental studies have shown that during the inflammatory reaction in the ear, protective mechanisms of local immune defense are activated. Activated neutrophils perform their function through phagocytosis and the formation of NETs. These studies contribute to supplementing the data on the immunopathological mechanisms of feline inflammatory polyps.

Sebaceous adenitis is observed in different animal species, with dogs being the most commonly dia... more Sebaceous adenitis is observed in different animal species, with dogs being the most commonly diagnosed. This study aimed to report a case of sebaceous adenitis in a 5-year-old male Akita dog weighing 35.8 kg, initially presented with pruritus and alopecia on the inner ear surfaces, face, and head. Over time, signs of changes in sebaceous glands appeared in other body parts. The dog was sent to a veterinary clinic in Kamyanets-Podilsky, Ukraine. During the clinical examination, the body temperature was 38.4°C, heart rate 78 bpm, and a respiratory rate 27 breaths per minute, with no change in appetite. Clinical and dermatological methods and histopathological examination were used to detect the disease. The hair on the head was curling, and the lesions appeared on the dorsal tail, the distal front and hind legs, the groin, and the abdomen. Initially, redness and itching occurred in the affected areas, and the skin lost elasticity and became dry. The hair was stuck together with gray crusts. The diagnosis was confirmed based on pathohistological studies. An inflammatory infiltrate with migration of lymphocytes, histiocytes, neutrophils, and atrophy of sebaceous glands was diagnosed, focusing on the pathology of the dermis. Treatment included topical therapy with shampoo applied for 3-5 minutes, then rinsed and followed by Conditioner for 2 minutes, over 30 days. Omega-3 was administered orally at 1000 mg twice daily. Isotretinoin (Roaccutane ® , 20 mg) was administered orally twice daily for 30 days. Moreover, Cyclosporine was dosed at 5 mg/kg once daily orally, on an empty stomach, for 30 days. During the treatment, signs of inflammation gradually disappeared, with itching and hyperemia disappearing from day 3. From day 7, desquamation and hair loss decreased, and on day 12, signs of new hair growth appeared. The areas were completely restored on day 28 of treatment. Sebaceous adenitis was found to lead to the destruction of sebaceous glands, causing scaling, hair loss, and skin inflammation, which could be a hereditary condition in Akitas. Immunomodulation and normalization of trophic processes in the skin are crucial in the treatment.

Scienceline Publication, 2024

Macropod progressive periodontal disease (MPPD), known as Lumpy Jaw, poses a persistent and poten... more Macropod progressive periodontal disease (MPPD), known as Lumpy Jaw, poses a persistent and potentially fatal threat in Western gray kangaroos when they are kept in captivity. Such a condition leads to the development of osteomyelitis and sepsis in Western gray kangaroos (Macropus fuliginosus). This case study presented the inaugural examination of hematological and biochemical aspects of MPPD with a progression toward sepsis in a captive environment. The primary objective of this research was to pinpoint hematological and biochemical indicators associated with severe MPPD in a Western gray kangaroo held in captivity. The study employed various methods, including clinical, radiographical, hematological, and biochemical analyses, as well as microbiological study methods. The case was a 2.5-year-old male wild Western gray kangaroo with fever (39.7 °C), dehydration, dyspnea, tachycardia, and involuntary jaw clenching due to stress and agitation. The kangaroo had a history of lethargy, anorexia, swelling of the soft tissues of the lower jaw on the left side, and tenderness during palpation. A radiograph of the head revealed mandible proliferative lesions. The hematological and biochemical examinations indicated an increase in the total count of leucocytes, level of neutrophils, number of erythrocytes, hematocrit level, and lymphopenia. Increased activity of alkaline phosphatase, amylase, and creatinine elevated azotemia. There was a decrease in the content of albumin, glucose, and total bilirubin. The bacteria, consisting of Fusobacteriaceae spp., Porphyromonadaceae spp., and Bacteroidaceae spp., were found and identified in all samples. However, this comprehensive diagnosis of MPPD based on clinical signs, radiography, and especially hematological and biochemical parameters of the septic process can be helpful in diagnosis and treatment.

World's Veterinary Journal, 2023

Discoid lupus erythematosus is an autoimmune disease that affects the skin in dogs. 6-year-old ma... more Discoid lupus erythematosus is an autoimmune disease that affects the skin in dogs. 6-year-old male German Shepherd weighing 38 kg was taken to the Small Animal Hospital at the University in Kyiv, Ukraine, with a history of progressive skin lesions. The indications of discoid lupus erythematosus in dogs manifested as red, scaly macules or papules on the skin's surface. These gradually develop into follicular plugging, disc-shaped plaques with adherent scales, and peripheral hyperpigmentation. The oral hydroxychloroquine was used for medication, and the prescribed dosage was 5.0 mg per kilogram of the dog's weight, administered once daily. The hydroxychloroquine was gradually reduced and discontinued within a month. Concurrent with the hydroxychloroquine treatment, the application of tacrolimus cream (Protopic ® 0.03%) was initiated. The veterinary physician also advised the dog owner to limit sun exposure to avoid any adverse effects. After a four-week period, there was a decrease in pruritus and erythema, and plaques had flattened although the skin still had some patchy hyperpigmentation. Approximately 3-4 weeks later, the veterinarian determined that the dog had achieved clinical remission as all the skin lesions had become completely flattened. The use of deproteinized calf blood extract gel (Solcoseril ® Gel for external 4.15 mg/1 g, Legacy led to the complete disappearance of the initial redness and prevented the appearance of new skin lesions. These results can be considered as a safe and effective alternative to conventional treatment methods.

Papers by Mykola Zhelavskyi

World's veterinary journal, Mar 25, 2024

World's Veterinary Journal, 2023

Discoid lupus erythematosus is lupus in dogs an autoimmune disease that affects the skin. A 6-yea... more Discoid lupus erythematosus is lupus in dogs an autoimmune disease that affects the skin. A 6-year-old, 38 kg, male German Shepherd dog was taken to the Small Animal Hospital at the University in Kyiv, Ukraine with a history of progressive skin lesions. The indications of discoid lupus erythematosus in dogs manifested as red, scaly macules or papules on the skin's surface. These gradually develop into follicular plugging, disc-shaped plaques with adherent scales, and peripheral hyperpigmentation. The oral hydroxychloroquine was used for medication and the prescribed dosage was 5.0 mg per kilogram of the dog's weight, administered once daily. The hydroxychloroquine was gradually reduced and discontinued within a month. Concomitant with the hydroxychloroquine treatment, the application of tacrolimus cream (Protopic® 0.03%) was initiated. The veterinary physician also advised the dog owner to limit sun exposure to avoid any adverse effects. After a four-week period, there was a...

New Approaches to the Diagnosiс of Pyometra in Cats and Dogs

Scienceline Publication, 2024

World's Veterinary Journal, 2023

World's veterinary journal, Mar 25, 2024

World's Veterinary Journal, 2023

New Approaches to the Diagnosiс of Pyometra in Cats and Dogs