title: Innate immune response against an oomycete pathogen Aphanomyces invadans in common carp (Cyprinus carpio), a fish resistant to epizootic ulcerative syndrome.
abstract: Infection with Aphanomyces invadans, also known as epizootic ulcerative syndrome, is a destructive disease of freshwater and brackishwater fishes. Although more than 130 species of fish have been confirmed to be susceptible to this disease, some of the commercially important fish species like common carp, milk fish and tilapia are reported to be resistant. Species that are naturally resistant to a particular disease, provide a potential model to study the mechanisms of resistance against that disease. In the present study, following experimental infection with A. invadans in common carp Cyprinus carpio, sequential changes in various innate immune parameters and histopathological alterations were monitored. Some of the studied innate immunity parameters viz. respiratory burst, alternative complement and total antiproteases activities of the infected common carp were higher compared to control fish, particularly at early stages of infection. On the other hand, some parameters such as myeloperoxidase, lysozyme and alpha-2 macroglobulin activities were not altered. Histopathological examination of the muscle at the site of injection revealed well developed granulomas at 12 days post infection, with subsequent regeneration of muscle fibers. From the results, it could be inferred that innate defense mechanisms of common carp are able to neutralize the virulence factors secreted by A. invadans, thereby, preventing its invasive spread and containing the infection. The results obtained here will help to better understand the mechanisms underlying resistance against A. invadans infection.
authors.affiliation: National Bureau of Fish Genetic Resources, Canal Ring Road, P.O. Dilkusha, Lucknow 226 002, Uttar Pradesh, India.
authors.forename: Manoj K
authors.initials: MK
authors.lastname: Yadav
authors.affiliation: National Bureau of Fish Genetic Resources, Canal Ring Road, P.O. Dilkusha, Lucknow 226 002, Uttar Pradesh, India. Electronic address: pradhanpk1@gmail.com.
authors.forename: Pravata K
authors.initials: PK
authors.lastname: Pradhan
authors.affiliation: National Bureau of Fish Genetic Resources, Canal Ring Road, P.O. Dilkusha, Lucknow 226 002, Uttar Pradesh, India.
authors.forename: Neeraj
authors.initials: N
authors.lastname: Sood
authors.affiliation: National Bureau of Fish Genetic Resources, Canal Ring Road, P.O. Dilkusha, Lucknow 226 002, Uttar Pradesh, India.
authors.forename: Dharmendra K
authors.initials: DK
authors.lastname: Chaudhary
authors.affiliation: National Bureau of Fish Genetic Resources, Canal Ring Road, P.O. Dilkusha, Lucknow 226 002, Uttar Pradesh, India.
authors.forename: Dev K
authors.initials: DK
authors.lastname: Verma
authors.affiliation: School of Environmental Biology, Awadhesh Pratap Singh University, Rewa 486 003, Madhya Pradesh, India.
authors.forename: U K
authors.initials: UK
authors.lastname: Chauhan
authors.affiliation: National Bureau of Fish Genetic Resources, Canal Ring Road, P.O. Dilkusha, Lucknow 226 002, Uttar Pradesh, India; Indian Institute of Farming System Research, Modipuram, Meerut 250 110, Uttar Pradesh, India.
authors.forename: Peyush
authors.initials: P
authors.lastname: Punia
authors.affiliation: National Bureau of Fish Genetic Resources, Canal Ring Road, P.O. Dilkusha, Lucknow 226 002, Uttar Pradesh, India.
authors.forename: Joy K
authors.initials: JK
authors.lastname: Jena
mesh_terms: D000818:Animals; D044744:Aphanomyces / Q000276:immunology* / Q000472:pathogenicity; D002347:Carps / Q000276:immunology*; D005393:Fish Diseases / Q000276:immunology*; D005398:Fisheries; D005618:Fresh Water; D007113:Immunity, Innate / Q000276:immunology*; D007194:India; D007239:Infections / Q000276:immunology / Q000662:veterinary*
keywords: Aphanomyces invadans; Cyprinus carpio; Epizootic ulcerative syndrome; Innate Immunity