title: Loss of infectivity of Neospora caninum oocysts maintained for a prolonged time.
abstract: The purpose of this study was to investigate whether sporulated Neospora caninum oocysts, which had been stored for 46 mo in a 2% sulfuric acid solution at 4 degrees C, remain morphologically viable and infective to gerbils (Meriones unguiculatus). Six gerbils were orally inoculated with doses of 400 or 1,200 oocysts. Two mo after inoculation, the animals did not show any clinical signs, had no histological lesions, and were seronegative for N. caninum at 1: 50 in an immunofluorescent antibody test. PCR using the brain from each gerbil did not reveal N. caninum specific DNA. We conclude that oocysts preserved for 46 mo are not infective, despite being morphologically intact.
authors.affiliation: Universidade Federal da Bahia, Escola de Medicina Veterinaria, Departamento de Patologia e Clinicas, Avenida Ademar de Barros, 500, Ondina, Salvador, Bahia, 40170-110, Brazil.
authors.forename: Rosangela Soares
authors.initials: RS
authors.lastname: Uzeda
authors.forename: Kattyanne De Souza
authors.initials: Kde S
authors.lastname: Costa
authors.forename: Sara Lima
authors.initials: SL
authors.lastname: Santos
authors.forename: Alexandre Moraes
authors.initials: AM
authors.lastname: Pinheiro
authors.forename: Maria Angela Ornelas
authors.initials: MA
authors.lastname: De Almeida
authors.forename: Milton M
authors.initials: MM
authors.lastname: McAllister
authors.forename: Luis Fernando Pita
authors.initials: LF
authors.lastname: Gondim
mesh_terms: D000143:Acids; D000818:Animals; D001921:Brain / Q000469:parasitology / Q000473:pathology; D002417:Cattle / Q000469:parasitology; D003048:Coccidiosis / Q000469:parasitology / Q000473:pathology / Q000662:veterinary*; D005243:Feces / Q000469:parasitology; D005260:Female; D005849:Gerbillinae / Q000469:parasitology*; D018688:Neospora / Q000235:genetics / Q000254:growth & development / Q000472:pathogenicity*; D033661:Oocysts / Q000254:growth & development*; D016133:Polymerase Chain Reaction / Q000379:methods; D012034:Refrigeration; D014774:Virulence
chemical_list: D000143:Acids