title: Immunization with Eimeria ninakohlyakimovae-live attenuated oocysts protect goat kids from clinical coccidiosis.
abstract: Caprine coccidiosis, affecting mainly young goat kids around the weaning period, is worldwide the most important disease in the goat industry. Control of caprine coccidiosis is increasingly hampered by resistances developed against coccidiostatic drugs leading to an enhanced need for anticoccidial vaccines. In the current study we conducted an oral immunization trial with live attenuated sporulated Eimeria ninakohlyakimovae oocysts. Sporulated E. ninakohlyakimovae oocysts were attenuated by X-irradiation technique. The experimental design included a total of 18 goat kids divided into the following groups: (i) animals immunized with attenuated E. ninakohlyakimovae oocysts at 5 weeks of age and challenged 3 weeks later with non-irradiated homologous oocysts (group 1); (ii) animals infected with non-attenuated E. ninakohlyakimovae oocysts at 5 weeks of age and challenged 3 weeks later with non-attenuated homologous oocysts (group 2); (iii) animals primary-infected with untreated E. ninakohlyakimovae oocysts at 8 weeks of age (control of the challenge infection, group 3); (iv) non-infected control animals (group 4). Goat kids immunized with live attenuated E. ninakohlyakimovae oocysts (group 1) excreted significantly less oocysts in the faeces (95.3% reduction) than kids infected with non-attenuated ones (group 2). Furthermore, immunization with live but attenuated oocysts resulted in ameliorated clinical coccidiosis compared to goat kids infected with untreated oocysts (group 2) and resulted in equally reduced signs of coccidiosis after challenge infection compared to acquired immunity driven by non-attenuated oocysts. Overall, the present study demonstrates for the first time that live attenuated E. ninakohlyakimovae oocysts orally administered showed almost no pathogenicity but enough immunogenicity in terms of immunoprotection. Importantly, vaccinated animals still shed low amounts of oocysts, guaranteeing environmental contamination and consecutive booster infections to sustain ongoing immunity.
authors.affiliation: Parasitology Unit, Department of Animal Pathology, Faculty of Veterinary Medicine, University of Las Palmas de Gran Canaria, Las Palmas, Spain. Electronic address: aruiz@dpat.ulpgc.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Ruiz
authors.forename: María Carmen
authors.initials: MC
authors.lastname: Muñoz
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Molina
authors.forename: Carlos
authors.initials: C
authors.lastname: Hermosilla
authors.forename: Marisa
authors.initials: M
authors.lastname: Andrada
authors.forename: Pedro
authors.initials: P
authors.lastname: Lara
authors.forename: Elisa
authors.initials: E
authors.lastname: Bordón
authors.forename: Davinia
authors.initials: D
authors.lastname: Pérez
authors.forename: Adassa María
authors.initials: AM
authors.lastname: López
authors.forename: Lorena
authors.initials: L
authors.lastname: Matos
authors.forename: Aránzazu Carmen
authors.initials: AC
authors.lastname: Guedes
authors.forename: Soraya
authors.initials: S
authors.lastname: Falcón
authors.forename: Yaiza
authors.initials: Y
authors.lastname: Falcón
authors.forename: Sergio
authors.initials: S
authors.lastname: Martín
authors.forename: Anja
authors.initials: A
authors.lastname: Taubert
mesh_terms: D000284:Administration, Oral; D000818:Animals; D003048:Coccidiosis / Q000469:parasitology / Q000473:pathology / Q000517:prevention & control / Q000662:veterinary*; D004539:Eimeria / Q000276:immunology*; D005243:Feces / Q000469:parasitology; D015511:Goat Diseases / Q000469:parasitology / Q000473:pathology / Q000517:prevention & control*; D006041:Goats; D007114:Immunization / Q000662:veterinary*; D007958:Leukocyte Count; D033661:Oocysts / Q000276:immunology*; D016052:Protozoan Vaccines / Q000008:administration & dosage / Q000592:standards*; D011897:Random Allocation; D014613:Vaccines, Attenuated / Q000592:standards
chemical_list: D016052:Protozoan Vaccines; D014613:Vaccines, Attenuated
keywords: Eimeria ninakohlyakimovae; Goats; Immunoprotection; Vaccine; X-irradiation