Caracterização molecular de mycoplasma da avicultura industrial dos estados de Minas Gerais e Espírito Santo

• Ano de defesa: 2013
• Autor(a) principal: Alexis de Matos Gomes
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Ciência Animal; Aves; Caracterização molecular
• Link de acesso: http://hdl.handle.net/1843/SMOC-9KPPZE

Fifty-four genotypic strains of Mycoplasma sp were obtained from three flocks of hens of Minas Gerais, one flock of hens of Espírito Santo, two flocks of broiler chickens of Espírito Santo and one flock of breeder of Minas Gerais (n=122). In order to determine the occurrence of mycoplasmas and the phylogenetic realtion of strains found in the poultry industry in the two states of Brazil, the nucleotide sequences were aligned and the variations of the transcribed region of the 16S and 23S intergenic ribosomal RNA space (IGRS) were used in the genetic characterization of strains. The nucleotide sequences were compared with sequences of strains accessible in GenBank: PG31, Mycoplasma gallisepticum (MG); WVU 1853, M. synoviae (MS); 17529, M. meleagridis (MM); 695, M. iowae (MI); PG16, M. gallinarum (MGN); PG30, M. iners (MIN); DD, M. gallinaceum (MGC); CKK, M. pullorum (MP) e 486, M. glycophilum (MGL). The results obtained for the Mycoplasma IGRS genetic sequencing clustered isolates were: 28.3% similar to MGN, 20.8% to MIN, 18.9% to MP, 17.0% to MG, 11.3% to MGC; 3 8% to MGL, 0% to MM and 0% to MI. Fourteen strains of MG were sequenced, including three commercial vaccines, two gglutination plate antigens and nine strains from ther poultry industry. The nucleotide sequences obtained were compared with sequences of field and vaccine strains of different parts of the world. The nucleotide sequences were aligned with the sequences of live vaccine strains used in the production of commercial vaccines (VAC1 and VAC3) and one inactivated vaccine (VAC2). The occurrence of MG vaccine strain in 3/18 (16.66%) of breeders tested indicated vaccine strain transfer, possibly from vaccinated layers, and recommends for strickt biosecurity. The live MG vaccine strains may represent an important risk for the official poultry health program. The phylogenetic relationship of the sequences of strains of MGN of Espírito Santo isolated from laying hens with respiratory signs with the sequences of non-pathogenic MGN strains isolated from healthy hens of the State of Minas Gerais was determined. MGN strains of Minas Gerais showed a discrete phylogenetic distance, while Espírito Santo MGN strains were highly related.