Seasonal diversity and safety evaluation of enterococci population from goat milk in a farm

Abstract

The presence and genetic diversity of enterococci in raw goat milk sampled in a farm during consecutive seasons were evaluated. Representative strains were screened for virulence determinants, susceptibility to antibiotics and the presence of genes involved in biogenic amine production. Counts of enterococci ranged between 2.80×10 1 and 2.50×10 3 cfu.mL -1 with summer samples showing the highest counts and winter samples the lowest. A total of 695 enterococci were isolated and genotyped. One hundred and thirty-three representative isolates from genotypes obtained in randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) analysis were identified as belonging to Enterococcus faecium (62.9%), Enterococcus faecalis (28.2%) and Enterococcus hirae (8.9%) species. A higher number of genotypes was observed in the summer and spring samples. The occurrence of antibiotic resistance and virulence genes was strain dependent, although the presence of genes did not always imply resistance, as occurred for vancomycin. All three species showed a high percentage of resistance to tetracycline. Strains from the warmer seasons (spring, summer and autumn) were resistant to a higher number of antibiotics and harboured a higher number of antibiotic resistance and virulence genes. All the strains produced tyramine, while only one E. hirae strain from a spring sample produced putrescine. The feed regime of goats during the warm seasons was the main difference between samples and thus, it could be proposed that the feed is responsible for the differences in the results between seasons.

Evaluation of Probiotic Properties and Safety of Enterococcus faecium Isolated From Artisanal Tunisian Meat “Dried Ossban”

“…All the five strains showed the expected amplicon of 1100 bp corresponding to the tdc gene ( Figure 6 ) but none harbored the histidine decarboxylase encoding gene, hdc . Our findings are in line with studies conducted by Inoǧlu and Tuncer (2013) , Ruiz et al (2016) , and Avci and Özden Tuncer (2017) where the authors found that all the analyzed E. faecium strains did not harbor the hdc gene but had the tdc gene. Histamine is the more toxic biogenic amine but the level of tyramine in food must also be controlled.…”

Colibacillary arthritis and severe osteomyelitis in lame goat kids due to management procedures

“…E. coli septicemia is normally seen at a much younger age, predominantly under ten days 4 . In older animals, E. coli septicemia, which can be associated with arthritis and osteomyelitis, is seen as an opportunistic infection often in immune compromised animals, 4 and in this case, most probably via infection of the intestinal tract since next to E. coli also E. hirae , a commensal of the gastrointestinal tract, 5 was cultured from an overfilled knee joint in one animal. Feed changes, stress, and diarrhoea could have created the opportunity for invasion of these intestinal tract commensals leading to hematogenous spreading.…”

Current Trends of Enterococci in Dairy Products: A Comprehensive Review of Their Multiple Roles

“…Enterococcus faecalis, E. faecium, E. durans, E. hirae, as well as (albeit infrequently) E. saccharominimum and E. italicus, have been isolated from the raw milk of cows, goats, and sheep (Figure 1) [31,36,38,39,41,[45][46][47][48][49][50][51][52][53][54][55][56][57][58][59][60][61][62][63][64]. Additionally, E. dispar, E. malodoratus, E. pseudoavium and E. gallinarum have been isolated both in cow's and in ewe's milk.…”