Etiological significance of the Glasser's disease pathogens in the structure of the complex pig respiratory syndrome

One of the features of diseases of the respiratory tract of pigs in pig farms of industrial type is the abundance of consociates of the Glässer's disease (bacteria, viruses, protozoa, helminths), which in the vast majority of cases are in the body in the form of various associations. Some of the pathogens involved in the emergence and development of complex respiratory syndrome are capable of causing the disease on their own, i.e. they are the primary pathogens. Most of the primary pathogens, in particular viruses of reproductive-respiratory syndrome, influenza, circoviruses and respiratory coronaviruses, have been studied quite extensively and in detail. At the same time, Haemophilus parasuis has not been sufficiently studied. For this purpose, the distribution of the pathogen of the Glässer's disease in case of complex respiratory syndrome of pigs in large industrial pig-breeding enterprises in the Omsk Region has been studied. In the bacteriological study of pathological material from pigs of various age groups, both infected and dead with symptoms of complex respiratory syndrome, the following bacteria were isolated: Escherichia coli - 48.3%, Mycoplasma hyopneumoniae - 20.6%, Actinobacillus pleuropneumoniae - 41.9%, Haemophilus parasuis - 22.4%, Pasteurella multocida - 15.3%, Salmonella cholerae suis - 7.4%, Bordetella bronchiseptica - 6.7%. In the serological study of blood serum of fattening pigs (6-month-old), in the indicated technological group of animals PRRS virus circulation was observed in 36.7% of cases, type 2 circovirus in 43.8%, which indicates a relatively widespread infection and virus carriage. In clinically healthy piglets of the growing group (4-month-old), antibodies to PRRS virus were noted in 25.8% of cases, and antibodies to type 2 circovirus in 27.3%. Associative infections caused by the viral pathogen in combination with hemophilic bacteria are more severe than mono-infections, and in most cases lead to the death of animals. Clinical and pathomorphological studies lead to the determination of the etiological role of the Glässer's disease pathogen in pigs. Cultures of H. parasuis were isolated, along with typical clinical and morphological infection symptoms, in 8.6% of nursery piglets.