title: Effects of T-2 Toxin on Turkey Herpesvirus-Induced Vaccinal Immunity Against Marek's Disease.
abstract: T-2 toxin, a very potent immunotoxic Type A trichothecene, is a secondary metabolite produced primarily by Fusarium spp., which grows on cereal grains and can lead to contaminated livestock feed. Repeated exposure to T-2 toxin has been shown to cause immunosuppression and decrease the resistance of exposed animals to a variety of infectious diseases; however, the effects of T-2 toxin on Marek's disease (MD) vaccinal immunity have not been reported. Four trials were conducted to determine the effects of T-2 toxin on vaccinal immunity against MD. Day-old, white leghorn chicks of Avian Disease and Oncology Laboratory line 15I5 × 71 were treated daily for 7 days via crop gavage with T-2 toxin at a sublethal dose of 1.25 mg/kg body weight. Treated and untreated chicks were also vaccinated with turkey herpesvirus (HVT) at hatch and were challenged with the JM strain of MD virus (MDV) at 8 days of age. Chickens were tested for HVT viremia at 1 wk postvaccination immediately before challenge, and for HVT and MDV viremia at 3 wk postchallenge. Chickens were observed for the development of MD lesions and mortality within 8 wk of age. T-2 toxin significantly reduced body weight and titers of HVT viremia within 7 days after hatch. T-2 toxin shortened the incubation period for the development of MD lesions and mortality, but only in unvaccinated chickens. The percent MD protection in T-2-toxin-treated, HVT-vaccinated chickens ranged from 82% to 96% and was comparable to that in HVT-vaccinated untreated control chickens (89%-100%). The data suggest that exposure of chickens to sublethal doses of T-2 toxin for 7 consecutive days after hatch may influence the development of 1) HVT viremia; and 2) MD lesions and mortality, but only in unvaccinated chickens.
authors.affiliation: A USDA-ARS Avian Disease and Oncology Laboratory, East Lansing, MI 48823.|B Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI 48824.|C Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI 48824.
authors.forename: E
authors.initials: E
authors.lastname: Kufuor-Mensah
authors.affiliation: B Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI 48824.
authors.forename: W M
authors.initials: WM
authors.lastname: Reed
authors.affiliation: B Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI 48824.
authors.forename: S
authors.initials: S
authors.lastname: Sleight
authors.forename: J
authors.initials: J
authors.lastname: Pestka
authors.affiliation: A USDA-ARS Avian Disease and Oncology Laboratory, East Lansing, MI 48823.
authors.forename: A M
authors.initials: AM
authors.lastname: Fadly
authors.affiliation: A USDA-ARS Avian Disease and Oncology Laboratory, East Lansing, MI 48823.
authors.forename: J R
authors.initials: JR
authors.lastname: Dunn
mesh_terms: D000818:Animals; D002645:Chickens; D005260:Female; D026002:Herpesvirus 1, Meleagrid / Q000276:immunology*; D008381:Herpesvirus 2, Gallid / Q000276:immunology*; D008297:Male; D008380:Marek Disease / Q000276:immunology* / Q000821:virology; D011201:Poultry Diseases / Q000276:immunology* / Q000821:virology; D013605:T-2 Toxin; D014611:Vaccination / Q000662:veterinary; D014765:Viral Vaccines / Q000276:immunology*
chemical_list: D014765:Viral Vaccines; D013605:T-2 Toxin
keywords: Marek's disease; T-2 toxin; mycotoxin; vaccination