title: Infection with Some Infectious Bursal Disease Virus Pathotypes Produces Virus in Chicken Muscle Tissue and the Role of Humoral Immunity as a Mitigation Strategy.
abstract: Infectious bursal disease virus (IBDV) causes important economic losses and negatively affects global trade in poultry and poultry products. This study determined the presence of IBDV in primary lymphoid tissues and muscle tissue of infected broilers and the role of vaccination as a mitigation strategy. In the first study, specific-pathogen-free (SPF) broiler chickens were challenged with STC (classical [cIBDV]), Indiana (variant [varIBDV]), rA (very virulent [vvIBDV]), or Ohio (serotype 2, avirulent) IBDV. Infection was confirmed in all groups, but only the cIBDV group experienced morbidity or mortality. Virus was only isolated in low titers from a few breast and/or thigh muscle tissue samples from cIBDV and vvIBDV-infected chickens. For the second study, SPF broilers from three different treatment groups were challenged with IBDV viruses that currently circulate in the United States, varIBDV or vvIBDV: 1) maternal antibody-positive (MAb+), vaccinated with recombinant HVT-IBDV vaccine (Vaxxitek®, Merial; MAb+/Vax); 2) MAb+, not-vaccinated (MAb+/Unvax); and 3) maternal antibody-negative, not-vaccinated chickens (MAb-/Unvax). MAb+/Vax and MAb+/Unvax chickens had significantly lower virus titers in primary lymphoid tissues compared to MAb-/Unvax chickens. No virus was detected in muscle tissues from any of the groups challenged with varIBDV, confirming the results of the first experiment. Only 1 of 36 (MAb+/Vax) and 2 of 36 (MAb+/Unvax) muscle samples were positive at minimal amounts (101.97EID50/ml) in vvIBDV challenge, compared to the 9 of 36 muscle samples that were positive in the MAb-/Unvax group. This study indicates that only cIBDV and vvIBDV strains can be found in muscle at low titers of SPF meat chickens and that the breeder vaccination with MAb transfer to progeny with or without accompanying progeny vaccination, as practiced in the United States, was an effective mitigation strategy for vvIBDV-challenged birds.
authors.affiliation: A Exotic and Emerging Avian Viral Diseases Research Unit, Southeast Poultry Research Laboratory, U.S. National Poultry Research Center, Agricultural Research Service, U.S. Department of Agriculture, 934 College Station Road, Athens, GA 30605.
authors.forename: Mariana Sá E
authors.initials: MS
authors.lastname: Silva
authors.affiliation: A Exotic and Emerging Avian Viral Diseases Research Unit, Southeast Poultry Research Laboratory, U.S. National Poultry Research Center, Agricultural Research Service, U.S. Department of Agriculture, 934 College Station Road, Athens, GA 30605.
authors.forename: Kateri
authors.initials: K
authors.lastname: Bertran
authors.affiliation: A Exotic and Emerging Avian Viral Diseases Research Unit, Southeast Poultry Research Laboratory, U.S. National Poultry Research Center, Agricultural Research Service, U.S. Department of Agriculture, 934 College Station Road, Athens, GA 30605.
authors.forename: Kira
authors.initials: K
authors.lastname: Moresco
authors.affiliation: B Food Animal Health Research Program, The Ohio State University/OARDC, 1680 Madison Avenue, Wooster, OH 44691.
authors.forename: Daral J
authors.initials: DJ
authors.lastname: Jackwood
authors.affiliation: A Exotic and Emerging Avian Viral Diseases Research Unit, Southeast Poultry Research Laboratory, U.S. National Poultry Research Center, Agricultural Research Service, U.S. Department of Agriculture, 934 College Station Road, Athens, GA 30605.
authors.forename: David E
authors.initials: DE
authors.lastname: Swayne
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology; D018175:Birnaviridae Infections / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D002645:Chickens; D056724:Immunity, Humoral; D007243:Infectious bursal disease virus / Q000235:genetics / Q000302:isolation & purification; D008221:Lymphoid Tissue / Q000276:immunology / Q000821:virology; D009132:Muscles / Q000276:immunology / Q000821:virology*; D011201:Poultry Diseases / Q000276:immunology / Q000821:virology*
chemical_list: D000914:Antibodies, Viral
keywords: IBDV; chicken muscle tissue; poultry industry; vaccination; variant strain