Evaluation of enterococci for potential probiotic utilization in dogs

Abstract

Some strains of the genus Enterococcus are effective probiotic bacteria if they meet safety and probiotic criteria. In our study, 17 canine enterococci previously selected from a group of 160 isolates based on safety criteria were screened for some functional properties relevant to their use as probiotics. The results of antimicrobial resistance testing showed sensitivity of eleven strains to EFSA recommended antimicrobials. In contrast, the most frequent resistance was observed for cefotaxim (15/17) and oxacillin (13/17). PCR detection of resistance genes (vanA, vanB, vanC, tetM, tetL, ermB, and mefA) revealed the presence of mefA gene in five Enterococcus faecium strains and vanA gene in one strain. The production of enzymes commonly associated with intestinal diseases was in general rare (β-glucosidase 2/17, α-chymotrypsin 1/17, N-acetyl-β-glucosaminidase 0/17, and β-glucuronidase 0/17). The measurement of strain survival rate (%) under the conditions simulating gastric (pH 2.5) and bile juices (0.3% bile) showed considerable differences between strains (< 0.01 to 4.7% after 90 min for gastric juices, 48.0 to 254.0% after 180 min for bile). The concentration of produced L-lactic acid ranged between 83.1 to 119.3 mmol/L after 48 h cultivation depending on the strain. All strains fermented 16 out of 49 different carbohydrates (range from 17 to 23/49). Antimicrobial activity was recorded for two strains against some species of Listeria sp. and Enterococcus sp. Finally, two E. faecium candidates (IK25 and D7) were selected for testing in dogs, and hereafter they could possibly extend the currently limited range of beneficial bacteria of canine origin used as a dietary supplement for dogs.

Characterization and Comparison of Enterococcus spp. Isolates from Feces of Healthy Dogs and Urine of Dogs with UTIs

“…Resistance to oxacillin is well documented in enterococci and it could be considered as intrinsic [32,[48][49][50]. Our data seem to confirm this statement, despite not all strains resulting resistant.…”

Application of Canine-Derived Enterococcus faecium DSM 32820 in Dogs with Acute Idiopathic Diarrhoea

“…This strain of canine origin was selected from 160 enterococci isolated from 105 healthy dogs. Our previous studies described its safety, potential probiotic properties and effect in vitro as well as in vivo [11,12]. As required, the selected strain meets the criteria proposed by EFSA for E. faecium species intended for use in animal nutrition [13].…”

“…The potential probiotic strain used in this canine experiment, E. faecium DSM 32820, was selected in our laboratory (Centre of Biosciences, Institute of Animal Physiology) from a group of 160 enterococci isolated from the feces of 105 dogs based on the results of its safety and probiotic criteria [10,11]. After in vitro testing, the E. faecium strain was also applied in vivo in order to obtain information on how clinically healthy dogs tolerate the daily administration of this canine-derived strain [12].…”

Influence of Probiotic Supplementation on Health Status of the Dogs: A Review

“…Several probiotic supplements have been reported to have health-promoting properties for both healthy and diseased dogs. Probiotics isolated from fresh fecal swabs of healthy dogs could also be used as a potent probiotic candidate as a dietary supplement for dogs [73,74].…”