Immunological status of highly productive cows with comorbid obstetric-gynecological and orthopedic pathology

Background. Research and clinical observation confirm a significant correlation between postpartum metabolic/obstetric diseases and the development of orthopedic pathology in highly productive cows. In particular, a study supported by the Russian Science Foundation (grant No. 24-26-00172) revealed a clear relationship between the development of purulent-necrotic lesions of the hooves and the occurrence of postpartum endometritis in high-yielding cows. In this study, the following groups of animals were formed by randomization: group 1 (n=28): cows with acute purulent-catarrhal postpartum endometritis; group 2 (n=25): animals with purulent-necrotic lesions of the hooves; group 3 (n=27): cows with a comorbid course of both pathologies; and the control group (n=23): clinically healthy animals. All individuals selected for the study had their jugular venous blood collected on an empty stomach into sterile tubes for subsequent immunological analysis. It was found that the comorbid course of these pathologies is significantly more severe than each of the diseases in isolation. This is evidenced by the immunological screening we conducted. In this regard, when an animal has multiple pathologies, an individual approach is necessary, which dictates the need for a comprehensive study of the clinical course of the main, concomitant, and even previous diseases, their comprehensive diagnosis, and rational treatment.

Purpose. The purpose of the present paper is to study the immunological status of highly productive cows with comorbid obstetric-gynecological and orthopedic pathology.

Materials and methods. To assess the dynamics of the clinical manifestation of hoof diseases, an orthopedic examination was conducted on a monthly basis throughout the year. During this examination, the following were evaluated: the degree and nature of hoof deformities; the intensity of corneal destruction; the presence of specific lesions such as pockets, delamination, and cracks; and the position of the thoracic and pelvic limbs. In cows with identified purulent-necrotic lesions during the postpartum period, a detailed obstetric and gynecological examination was additionally performed. It included a clinical examination, transrectal palpation, and ultrasound scanning, which was performed using the Scanner Falco device (8 MHz). Ultrasound was used to determine the size, echodensity, tissue homogeneity, and echogenicity of the reproductive structures. For immunological studies, blood was taken from the jugular vein of sick animals and cows from the control group (n=23) in the morning before feeding into sterile tubes. The total protein content in the blood serum of cows was determined using the biuret reaction, and the protein fractions were determined using the nephelometric method, and the A/G ratio was calculated. The amount of C-reactive protein was determined using the immunofluorescence method. The concentration of ceruloplasmin (CP) in the blood serum was determined by the standard method based on the oxidation of p-phenylenediamine with the participation of CP. The level of fibrinogen was determined spectrophotometrically, haptoglobin – by turbidimetric method. The level of circulating immune complexes (CIC) and their fractional composition were analyzed on the basis of determination of their molecular weight. The concentrations of interleukins (IL-1a and IL-8) and tumor necrosis factor-α (TNF-α) were measured by solid-phase enzyme immunoassay using commercial kits of monoclonal antibodies and reagents manufactured by Cytokin LLC, Saint Petersburg, Russia.

Results. According to the Tukey multiple comparison analysis, the most significant increase in the level of CIC was observed in the group of animals with comorbid pathology. This indicates that the combined course of endometritis and hoof diseases leads to a more severe systemic inflammatory response compared to isolated forms of the diseases. This is evidenced by the indicators of protein metabolism, the level of acute phase proteins, the cytokine profile, and the amount of circulating immune complexes in the blood samples of the experimental animals.

Conclusion. Currently, there is an urgent need for a comprehensive fundamental study of comorbidity in veterinary practice. The results of our research demonstrate that the comorbid course of orthopedic and obstetric-gynecological pathologies in high-yielding animals is characterized by a more severe clinical picture compared to isolated forms of monopathologies. This is evidenced by our immunological screening. In this regard, when an animal has multiple pathologies, an individual approach is necessary, which requires a comprehensive study of the clinical course of the main, concomitant, and even previous diseases, as well as their comprehensive diagnosis and rational treatment. In the future, it is necessary to create a universal tool that allows veterinarians to instantly and easily assess the structure, severity, and possible consequences of concomitant diseases in animals, conduct targeted diagnostics, and then prescribe the correct set of medical measures.