Role of abiotic factors in the manifestation of Bombyx mori Nucleopolyhedroviru

Abstract

Mycoplasma is considered as commensal microorganism, however, due to a decrease in the natural resistance of the macroorganism, they can cause an infectious process of various localization. Diseases caused by Мycoplasma are noted in farm animals and birds of various species. A significant part of the livestock can be affected, which entails serious economic damage. The purpose of the presented work was to study the clinical signs and pathological changes in enzootic pneumonia caused by Mycoplasma in pigs. When observing 18 four-month-old Landrace piglets living in a vivarium, one animal showed periodic dry cough, decreased fatness, lethargy and decreased activity, body temperature 39.5 ° C, heart rate - 130 /min, respiratory rate - 42 /min. The other animals were clinically healthy. After slaughter, autopsy of 18 animals revealed pathological changes of varying severity in three: fibrinous pleurisy, lobar fibrinous pneumonia, pulmonary edema. Microscopy of histological preparations selected from fragments of the affected lungs revealed Mycoplasma and changes characteristic of interstitial pneumonia: neutrophil infiltration, fibrosis. Conclusions: In the described case, enzootic pneumonia is not a highly contagious disease: out of 18 animals, only one piglet had clinical signs, and three had pathological changes. Due to the subclinical process, manifested by rare dry coughing, the pathological changes may remains unnoticed until the autopsy of the animals.