Isolation of Arcobacter spp from the milk of dairy cows in Brazil

Bacteriologic examinations were performed on 188 milk samples collected from cows from 11 farms for diagnosis of mastitis in three cities of Rio Grande do Sul, Brazil. Among the common causes of mastitis, the most frequent isolates were Staphylococcus aureus, followed by Corynebacterium sp, Streptococcus uberis, Streptococcus dysgalactiae and Streptococcus agalactiae. Bacteriologic examination of 32 milk samples from one farm didn't show bacteria known as common etiologic agent of mastitis. Six samples of Arcobacter spp typed by genotypic tests as Arcobacter cryaerophilus (five strains) and Arcobacter butzleri (one strain) were isolated from cows' milk of that farm. It is reported the isolation of Arcobacter species from the milk of cows in absence of clinical signs of mastitis. This is the first report of the detection of the microorganisms in the milk of dairy cows in Brazil. No previous reports are known from other countries.

Foram realizados exames bacteriológicos em 188 amostras de leite colhidas de vacas de 11 propriedades leiteiras para diagnóstico de mastite, em três municípios no Rio Grande do Sul, Brasil. Entre as causas comuns de mastite, os isolados mais freqüentes foram Staphylococcus aureus, seguido de Corynebacterium sp, Streptococcus uberis, Streptococcus dysgalactiae e Streptococcus agalactiae. O exame bacteriológico realizado em 32 amostras de leite de vacas de uma propriedade não demonstrou a presença de bactérias conhecidas como causadoras de mastite. Foram isoladas do leite de vacas desta propriedade seis amostras de Arcobacter spp, classificadas por testes moleculares como Arcobacter cryaerophilus (cinco amostras) e Arcobacter butzleri (uma amostra). É relatado o isolamento de espécies de Arcobacter do leite de vacas na ausência de sinais clínicos de mastite. Este é o primeiro relato da detecção dos microorganismos no leite de vacas leiteiras no Brasil.

Epidemiological characterization of Staphylococcus aureus isolated from bovine mastitis in Porto Alegre (Rio Grande do Sul, Brazil)

One hundred strains of S. aureus isolated from bovine mastitis in Porto Alegre (Brazil) were analysed for biotype, phage pattern and ability to produce protein A. Biotype could be defined in 76 per cent of the isolates: 52 per cent belonged to biotype C (bovine origin) and 24 per cent to biotype A (human origin). Phage typing performed with the human basic set (Routine Test Dilution - RTD x 100) allowed the classification of 42 per cent of samples. Low titers of protein A were detectable in 89 per cent of the strains