Andualem Tonamo
57218242741
Publications - 2
Identification of ovine-associated staphylococci by MALDI-TOF mass spectrometry
Publication Name: Acta Alimentaria
Publication Date: 2021-06-01
Volume: 50
Issue: 3
Page Range: 210-218
Description:
The objective of this study was to use matrix-assisted laser desorption ionisation–time of flight mass spectrometry (MALDI-TOF MS) for the identification of ovine-associated staphylococci. Presumptive Staphylococcus isolates were recovered from ovine udder surface (US), individual raw milk, bulk tank milk, and cheese samples and were characterised by conventional phenotypic methods. A total of 69 bacterial isolates were further confirmed by MALDI-TOF MS. Forty-two (60.9%) of 69 isolates were successfully identified on genus and species level. Two thirds (n 5 28) of the 42 identified isolates were shown to be Staphylococcus spp. These 28 staphylococcal isolates formed two clusters, one consisting of 22 Staphylococcus aureus strains and the other composed of 6 non-aureus staphylococci, including S. simulans (n 5 3), S. auricularis, S. equorum, and S. haemolyticus. MALDI-TOF MS has proven to be a reliable tool for the identification of staphylococci from raw sheep’s milk, especially bulk tank milk; however, currently it appears to be less useful for the identification of bacterial isolates originating from ovine US samples. This is the first study to evaluate the applicability of MALDI-TOF MS for identification of Staphylococcus spp. in ovine raw milk, cheese, and US samples in Hungary.
Open Access: Yes
Bacteriological quality of raw ovine milk from different sheep farms
Publication Name: Animals
Publication Date: 2020-07-01
Volume: 10
Issue: 7
Page Range: 1-9
Description:
The primary purpose of this research was to examine the bacteriological properties of raw ovine milk produced by Merino, Tsigai, Dorper, Lacaune, and British Milk Sheep flocks on four sheep farms located in the eastern part of Hungary. In addition to individual raw milk (IRM) and bulk tank milk (BTM) samples, the udder surface (US) of ewes was also tested for bacteriological quality. A total of 77 US, 77 IRM, and 10 BTM samples were collected in the early morning during regular milking sessions. The samples, kept cooled at temperatures below 4◦C, were delivered to the microbiological laboratory and were examined immediately. The relatively low numbers of bacteria in both US and IRM samples reflected good housing conditions of ewes kept on the four farms studied. However, BTM samples had up to 3.5–4.0 log10 CFU/mL higher mean bacterial counts than their IRM counterparts, and the mean levels of bacteria in BTM on two farms even exceeded the regulatory limit of 6.18 log10 CFU/mL. Further studies need to be performed to clarify this issue.
Open Access: Yes
DOI: 10.3390/ani10071163