title: Egg quality in laying hens exposed to Mycoplasma gallisepticum F-strain attenuated vaccine.
abstract: Mycoplasma gallisepticum causes coughing, ocular and nasal discharge, reduction in feed intake, lower and uneven growth, decline in egg production and quality, and increase in mortality. Among the attenuated vaccination strains, MGF can reduce clinical signs and lesions in layer hens, stimulate immune responses of cellular and humoral basis, act as an instrument of competitive exclusion in relation to field strains, and reduce the use of antimicrobials. This study aimed to investigate the effects of attenuated MG F-strain vaccination on egg quality in 3 groups of 30 hens each, being one control and 2 vaccinated. Vaccination was applied by ocular route at 8 and 12 wk of age. Comparisons were made among unvaccinated hens; vaccinated at 8 wk of age; and vaccinated at 8 and 12 wk of age. There were no statistical differences in eggshell thickness and weight among groups. Eggs from twice vaccinated birds yielded a Haugh unit significantly lower than the other groups without affecting egg classification. There was no significant difference in ELISA results between the vaccinated groups.
authors.affiliation: Departamento de Saúde Coletiva Veterinária e Saúde Pública/Faculdade de Veterinária/Universidade Federal Fluminense (UFF), Rua Vital Brazil Filho, number 64, Niterói, 24230-340, Brazil.
authors.forename: L D S
authors.initials: LD
authors.lastname: Machado
authors.affiliation: Departamento de Saúde Coletiva Veterinária e Saúde Pública/Faculdade de Veterinária/Universidade Federal Fluminense (UFF), Rua Vital Brazil Filho, number 64, Niterói, 24230-340, Brazil.
authors.forename: F F D
authors.initials: FF
authors.lastname: Santos
authors.affiliation: Departamento de Saúde Coletiva Veterinária e Saúde Pública/Faculdade de Veterinária/Universidade Federal Fluminense (UFF), Rua Vital Brazil Filho, number 64, Niterói, 24230-340, Brazil.|Departamento de Zootecnia e Desenvolvimento Agrossocioambiental Sustentável/Faculdade de Veterinária/Universidade Federal Fluminense (UFF), Niterói, 24230-340, Brazil.
authors.forename: C K
authors.initials: CK
authors.lastname: Togashi
authors.affiliation: Departamento de Saúde Coletiva Veterinária e Saúde Pública/Faculdade de Veterinária/Universidade Federal Fluminense (UFF), Rua Vital Brazil Filho, number 64, Niterói, 24230-340, Brazil.
authors.forename: D L D C
authors.initials: DL
authors.lastname: Abreu
authors.affiliation: CEVA Animal Health, Paulínia, 13140-000, Brazil.
authors.forename: J C
authors.initials: JC
authors.lastname: Pimentel
authors.affiliation: CEVA Animal Health, Paulínia, 13140-000, Brazil.
authors.forename: L
authors.initials: L
authors.lastname: Sesti
authors.affiliation: Departamento de Saúde Coletiva Veterinária e Saúde Pública/Faculdade de Veterinária/Universidade Federal Fluminense (UFF), Rua Vital Brazil Filho, number 64, Niterói, 24230-340, Brazil.
authors.forename: V L D A
authors.initials: VL
authors.lastname: Pereira
authors.affiliation: Departamento de Saúde Coletiva Veterinária e Saúde Pública/Faculdade de Veterinária/Universidade Federal Fluminense (UFF), Rua Vital Brazil Filho, number 64, Niterói, 24230-340, Brazil.
authors.forename: E R D
authors.initials: ER
authors.lastname: Nascimento
mesh_terms: D000818:Animals; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000494:pharmacology*; D002645:Chickens; D004306:Dose-Response Relationship, Immunologic; D004528:Egg Shell / Q000187:drug effects* / Q000502:physiology; D005260:Female; D009175:Mycoplasma Infections / Q000382:microbiology / Q000517:prevention & control / Q000662:veterinary; D045686:Mycoplasma gallisepticum / Q000276:immunology*; D010063:Ovum / Q000187:drug effects* / Q000502:physiology; D011201:Poultry Diseases / Q000382:microbiology / Q000517:prevention & control; D014611:Vaccination / Q000662:veterinary; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D001428:Bacterial Vaccines; D014613:Vaccines, Attenuated
keywords: Mycoplasma gallisepticum; egg; layer; serology