Study on Coinfection of Mycoplasma gallisepticum and Low Pathogenic Avian Influenza Virus H9 in Broilers

Abstract

Avian influenza viruses (AIVs) belong to the family Orthomyxoviridae which consists of three genera known as Influenza virus-A,-B and-C. The influenza viruses, which can cause infections in avian species belong to genus influenza virus A which can produce two different types of diseases on the basis of their virulence and pathogenicity. Thus are classified as a highly pathogenic avian influenza virus (HPAIV) and a low pathogenic avian influenza virus (LPAIV). Recent outbreaks of LPAIV H 9 N 2 in Asian countries such as in Pakistan and China revealed that this subtype has become endemic in poultry population of these countries. Meager literature is available about its pathogenicity. This study was made to ascertain the pathogenesis of H 9 subtype AIVs in broilers along with most prevalent respiratory pathogen Mycoplasma gallisepticum under field conditions. In first part of study, challenge organisms (H 9 virus and Mycoplasma gallisepticum) were isolated from field samples and experimental inoculum was prepared. In second part, pathogenesis of H 9 virus in association with M. gallisepticum was carried out under controlled environmental conditions. The virus prevailing in Pakistan was found nonpathogenic as only slight diarrhoea and depression in few birds was seen while clinical signs and lesions produced grossly and microscopically were more severe in form of severe conjunctivitis and facial edema and respiratory involvement with hemorrhagic and pneumonic lungs and degenerative and lytic necrosis in kidneys in birds infected co-infected with H 9 virus and Mycoplasma gallisepticum as compared to other groups which were infected with single pathogens. Immunohistochemical detection of viral antigen revealed that replication of virus was more severe in birds infected with H 9 virus and Mycoplasma gallisepticum as compared to other groups. In conclusion, the virus subtype H 9 circulating in Pakistan is low pathogenic in nature with affinity for respiratory system and urinary system while coinfection with Mycoplasma gallisepticum is the most important factor enhancing the pathogenicity of H 9 virus under field conditions.

Viral interference between H9N2-low pathogenic avian influenza virus and avian infectious bronchitis virus vaccine strain H120 in vivo

“…Viral infection has been reported to induce loss of TC cilia, hyperplasia, hyperemia, and [37,38]. Histopathological changes induced in the trachea, lungs, liver and intestine of PCR-positive chicks, during viral interference between AIV and IBV, were in accord with those previously reported [39][40][41].…”

Evaluation in broilers of aerosolized nanoparticles vaccine encapsulating imuno-stimulant and antigens of avian influenza virus/Mycoplasma gallisepticum

“…Impact of aerosolization of liposomal chicken vaccine a , incorporating H9N2 and MG antigens in presence and absence of Echinacea extract (EE), on mucosal immunity to MG MG. [1][2][3][4][5][6] Means in numerators of a column followed by different Arabic numerical -superscripts are significantly different (P<0.05); similarly, means in denominators of a column followed by different Arabic numerical -superscripts are also significantly different (P<0.05).…”

“…The authors declare that they have no conflict of interests among the authors or any other parties; in addition, the authors declare that they have no financial or non-financial interests that undermine, by challenged (positive controls); TRT 5 = Vaccine administration containing H9N2, MG, EE, and deprived of challenge; TRT 6 = Deprived of antigens and EE, and of challenge (Negative Controls) [1][2][3][4][5] Means in a column followed by different Arabic numerical -superscripts are significantly different (P<0.05).…”

“…The coinfection of H9N2 with Mycoplasma gallisepticum (MG) augmented significantly their individual pathogenicity in poultry, leading into significant losses in production [5][6][7][8]. The prevalence of MG is also global [9], including its prevalence in poultry of the MENA region [10,11].…”

Study on Tissue Tropism and Molecular Detection of VP2 Gene of Infectious Bursal Disease Virus in Experimentally Infected Broiler Tissues

“…Histopathological examination: On day 3 rd , 5 th , 9 th and 14 th of post infection, from each group five birds were slaughtered, gross and histopathological lesions on lymphoid organs and non lymphoid organs were observed (Subtain et al, 2011).…”