title: Immunogenicity and protection efficacy evaluation of avian paramyxovirus serotype-1 (APMV-1) isolates in experimentally infected chickens.
abstract: Vaccine failures after Newcastle disease vaccination with the current commercial vaccines have been reported and are associated with many factors, including genotypic and antigenic differences between vaccine and outbreak strains, although all APMV-1 members belong to one serotype. We assessed the immunoprotection ability of four thermostable, low-virulent Newcastle disease-virus isolates from Ugandan waterfowl against challenge with a virulent strain (MDT = 36.8 h, ICPI = 1.78) isolated from morbid chicken. Six-week-old commercial Leghorn layers, challenged at 21 days post immunization were used. Four isolates designated: NDV-133/UG/MU/2011, NDV-177/UG/MU/2011, NDV-178/UG/MU/2011 and NDV-173/UG/MU/2011 induced mean haemagglutinin inhibition antibody titres of log29.3, 8.2, 6.3 and 2.0, respectively, at 21 days post immunization. The antibody titres correlated with the protection rates (R² = 0.86, p < 0.007) of 60%, 50%, 20% and 0% of birds, respectively, against challenge at 14 days post challenge. Further evaluation of these and more low-virulent isolates might provide an alternative to the current commercial vaccine failures.
authors.affiliation: a College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University , Kampala , Uganda.|b Uganda Industrial Research Institute (UIRI) , Kampala , Uganda.
authors.forename: John Bosco
authors.initials: JB
authors.lastname: Omony
authors.affiliation: a College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University , Kampala , Uganda.
authors.forename: Agnes
authors.initials: A
authors.lastname: Wanyana
authors.affiliation: c Mbarara Zonal Agricultural Research and Development Institute (MBAZARDI), National Agricultural Research Organization (NARO) , Mbarara , Uganda.
authors.forename: Halid
authors.initials: H
authors.lastname: Kirunda
authors.affiliation: a College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University , Kampala , Uganda.
authors.forename: Kizito Kahooza
authors.initials: KK
authors.lastname: Mugimba
authors.affiliation: a College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University , Kampala , Uganda.
authors.forename: Jessica Lukanga
authors.initials: JL
authors.lastname: Nakavuma
authors.affiliation: d Uganda National Council for Science and Technology (UNCST) , Kampala , Uganda.
authors.forename: Maxwell
authors.initials: M
authors.lastname: Otim-Onapa
authors.affiliation: a College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University , Kampala , Uganda.
authors.forename: Denis Karuhize
authors.initials: DK
authors.lastname: Byarugaba
mesh_terms: D000818:Animals; D001483:Base Sequence; D002642:Chick Embryo; D002645:Chickens; D004279:DNA, Viral / Q000235:genetics; D000071497:Immunogenicity, Vaccine; D009521:Newcastle Disease / Q000517:prevention & control*; D009522:Newcastle disease virus / Q000276:immunology* / Q000472:pathogenicity; D011201:Poultry Diseases / Q000517:prevention & control*; D012367:RNA, Viral; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014765:Viral Vaccines / Q000276:immunology*; D014774:Virulence; D014779:Virus Replication / Q000502:physiology
chemical_list: D004279:DNA, Viral; D012367:RNA, Viral; D014765:Viral Vaccines
keywords: Newcastle disease; immunity; immunogenicity; pathogenicity; protective efficacy; vaccine