The Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) identification versus biochemical tests: a study with enterobacteria from a dairy cattle environment.
Mastitis adversely affects milk production and in general cows do not regain their full production levels post recovery, leading to considerable economic losses. Moreover the percentage decrease in milk production depends on the specific pathogen that caused the infection and enterobacteria are responsible for this greater reduction. Phenotypic tests are among the currently available methods used worldwide to identify enterobacteria; however they tend to misdiagnose the species despite the multiple tests carried out. On the other hand The Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) technique has been attracting attention for its precise identification of several microorganisms at species level. In the current study, 183 enterobacteria were detected in milk (n=47) and fecal samples (n=94) from cows, and samples from water (n=23) and milk lines (n=19). All these samples were collected from a farm in Rio de Janeiro with the specific purpose of presenting the MALDI-TOF MS technique as an efficient methodology to identify Enterobacteriaceae from bovine environments. The MALDI-TOF MS technique results matched the biochemical test results in 92.9% (170/183) of the enterobacteria species and the gyrB sequencing confirmed 100% of the proteomic technique results. The amino acid decarboxylation test made the most misidentifications and Enterobacter spp. was the most misidentified genus (76.9%, 10/13). These results aim to clarify the current biochemical errors in enterobacteria identification, considering isolates from a bovine environment, and show the importance for more careful readings of phenotypic tests which are often used in veterinary microbiology laboratories.
['Rodrigues|Naiara Miranda Bento|NM|', 'Bronzato|Greiciane França|GF|', 'Santiago|Gabrielli Stefaninni|GS|', 'Botelho|Larissa Alvarenga Batista|LA|', 'Moreira|Beatriz Meurer|BM|', 'Coelho|Irene da Silva|ID|', 'Souza|Miliane Moreira Soares de|MM|', 'Coelho|Shana de Mattos de Oliveira|SM|']
D000818:Animals D002417:Cattle D027081:DNA Gyrase D004755:Enterobacteriaceae D005260:Female D005798:Genes, Bacterial D008414:Mastitis, Bovine D008892:Milk D010641:Phenotype D040901:Proteomics D017422:Sequence Analysis, DNA D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
Enterobacteria identification Bovine mastitis Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry