| Full text | |
| Author(s): |
Barreiro, Juliana R.
[1]
;
Goncalves, Juliano L.
[1]
;
Grenfell, Rafaella
[2]
;
Leite, Renata F.
[1]
;
Juliano, Luiz
[2]
;
Santos, V, Marcos
Total Authors: 6
|
| Affiliation: | [1] V, Univ Sao Paulo, Fac Med Vet & Zootecnia, Dept Nutr & Prod Anim, Pirassununga, SP - Brazil
[2] Univ Fed Sao Paulo, Dept Biofis, Sao Paulo, SP - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | Brazilian Journal of Microbiology; v. 49, n. 4, p. 801-807, OCT-DEC 2018. |
| Web of Science Citations: | 2 |
| Abstract | |
ABSTRACT The present study aimed to compare two MALDI-TOF identification methods [(a) direct sample identification after pre-incubation; or (b) use of bacteria isolated on pre-culture)] to standard, traditional bench microbiology. A total of 120 quarter milk samples from 40 Holstein lactating cows were screened based on culture-positive results obtained by microbiological culture (reference method) with the following numbers of quarters positive per cow: 4 cows with 1, 8 cows with 2, 12 cows with 3 and 16 cows with 4 infected quarters per cow. For direct identification method, quarter milk samples (n = 120) were skimmed by centrifugation (10,000 × g/10 min) and pre-incubated at 37 ºC for 12 h. After pre-incubation, quarter milk samples were submitted to total bacterial count by flow cytometry and for a preparation protocol for bacterial ribosomal protein extraction followed by MALDI-TOF MS analysis. The direct MALDI-TOF MS identification method compared to microbiological culture correctly identified isolates of coagulase-negative Staphylococci (27.2%), Streptococcus agalactiae (21.8%), Staphylococcus aureus (14.2%), and Streptococcus uberis (5.2%). The pre-incubation protocol of milk samples, associated to the direct identification method by MALDI-TOF MS, did not increase the identification at species level (score >2.0) of pathogens causing subclinical mastitis in comparison to the method without previous incubation. (AU) | |
| FAPESP's process: | 11/15815-4 - Rapid identification of microorganisms by mastitis causing mass spectrometry |
| Grantee: | Marcos Veiga dos Santos |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 11/14456-0 - Rapid identification of microorganisms causing mastitis by mass spectrometry |
| Grantee: | Juliana Regina Barreiro |
| Support Opportunities: | Scholarships in Brazil - Doctorate |