Association between spoligotype-VNTR types and virulence of Mycobacterium bovis in cattle

GARBACCIO SERGIO; MACÍAS, ANALÍA; SHIMIZU, ERNESTO; PAOLICCHI, FERNANDO; PEZZONE, NATALIA; MAGNANO, GABRIEL; ZAPATTA, LAURA; ABDALA, ALEJANDRO; TARABLA, HÉCTOR; PEYRU, MAITE; CAIMI, KARINA; ZUMÁRRAGA, MARTÍN JOSÉ; CATALDI, ANGEL

VIRULENCE

LANDES, BIOSCIENCE

Lugar: AUSTIN; Año: 2014 vol. 5 p. 1 - 6

2150-5608

Mycobacterium bovis is the causative agent of bovine tuberculosis, a disease thataffects approximately 5% of Argentine cattle. The aim of this research was to study if itis possible to infer the degree of virulence of different M. bovis genotypes based onscorified observations of tuberculosis lesions in cattle.In this study, we performed association analyses between several parameterswith tuberculosis lesions: M. bovis genotype, degree of progression of tuberculosis andanimal age. For this purpose, the genotype was determined by spoligotyping and thedegree of bovine tuberculosis gross lesion was quantified with a score based on clinicalobservations (number, size and location of granulomas along with histopathologicfeatures). This study was performed with naturally infected cattle of slaughterhousesfrom three provinces in Argentina.A total of 265 M. bovis isolates were obtained from 378 pathological lesionsamples and 192 spoligotyping and VNTR (based on ETR sequences) typing patternswere obtained. SB0140 was the most predominant spoligotype, followed by SB0145.The spoligotype with the highest lesion score was SB0273 (median score of 27 +/-4.46), followed by SB0520 (18 +/- 5.8). Furthermore, the most common spoligotype,SB0140, had a median score of 11 +/- 0.74. Finally, the spoligotype with the lowestscore was SB0145 (8 +/- 1.0). ETR typing of SB0140, SB0145, SB0273, SB0520 didnot subdivide the lesion scores in those spoligotypes.In conclusion, SB0273 and SB0520 were the spoligotypes with the strongestassociation with hypervirulence and both spoligotypes were only found in Río Cuarto atthe south of Córdoba province. Interestingly, these is no other report of any of thesespoligotyes in Latin America.