Pathomorphology of spontaneous coronaviral infection with SARSCоV-2 in maine coon kittens

 Pathological diagnostics is a mandatory and one of the most important methods for diagnosing animal diseases. Competent use of the methods of pathological and histological diagnostics allows in the shortest possible time to make the correct preliminary diagnosis, to carry out complicating diseases, and additional laboratory tests in a timely manner. At the same time, the pathological and morphological changes in the body of animals with a new zoonotic disease, COVID-19, have not been sufficiently studied or are not studied at all. This paper describes the pathological processes and histological changes in maine coon kittens with spontaneous SARSCoV-2  coronavirus infection. The obtained research results are presented in the  form of detailed pathological and histological diagnoses. It has been established that the leading structural changes in kittens’ bodies are characterized by the development of congenital and postnatal malnutrition, the predominance of profound disorders of the respiratory and cardiovascular systems: alveolar emphysema of the anterior and middle lobes of the lungs with areas of atelectasis and small focal interstitial  pneumonia in them, atelectasis of the caudal lobes of the lungs (in kittens 1–2 days of age); alveolar emphysema, edema (“carmine lungs”) of the lungs, large-focal interstitial pneumonia, sclerotization of the lungs with localization in the diaphragmatic lobes (at 10–14 days of age); acute expansion of the heart; acute venous hyperemia and edema of internal organs; pronounced postmortem blood coagulation in the cavities of the heart, large arteries and veins. Complicating processes are granular and small-droplet fatty degeneration of parenchymal organs, the development of which, apparently, is  due to a combination of hemodynamic disturbances, prolonged hypoxia and intoxication of the animal body. Considering the severity and depth of structural disorders, primarily in the lungs of newborn animals, it can be concluded that the kittens are infected vertically (transplacentally). 

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