Combined administration of bacteriocin- -producing, probiotic strain Enterococcus faecium CCM7420 with Eleutherococcus senticosus and their effect in rabbits

Influence of Three Probiotics Strains, Lactobacillus rhamnosus GG, Bifidobacterium animalis subsp. Lactis BB-12 and Saccharomyces boulardii CNCM I-745 on the Biochemical and Haematological Profiles and Body Weight of Healthy Rabbits

Simple Summary

Currently, probiotics are used as growth promoters on a large scale to improve the productivity of several animals’ species within the aim of reducing the presence of antibiotic residues in animal products consumed by humans. Several reports evidenced the positive effect of probiotic supplementation on the growth performances and health of rabbits, mainly through the balance of the intestinal microbiota of the host animal. Therefore, certain probiotics, including Lactobacilli, Bifidobacteria, Saccharomyces, can improve the biochemical and haematological profiles, especially in production animals. In this context, this study was performed on rabbits for the economic importance they play as a source of meat proteins in developing countries and their use as experimental models in research and biomedicine. This study then aimed to evaluate the effect of three strains of probiotics: Lactobacillus rhamnosus GG Bifidobacterium animalis subsp. Lactis BB-12 and Saccharomyces boulardii CNCM I-745, on the biochemical and haematological parameters and their influence on the rabbit’s weight of the ITELV2006 strain. The findings evidenced that the probiotic strain affected the biochemical and haematological parameters. Further, the strains showed a positive effect on the weight gain of the rabbits.

Abstract

This study aimed to investigate the effects of three strains of probiotics, these being Lactobacillus rhamnosus GG, Bifidobacterium animalis subsp. Lactis BB-12 and Saccharomyces boulardii CNCM I-745, on the body weight, animal performances and blood parameters of rabbits (male and female) of the ITELV2006 strain. The supplementation of the feed of the rabbits with the three probiotic strains allowed observing positive effects on most of the biochemical and haematological parameters investigated during a period of 60 days (30 days of supplementation and 30 days without treatment). Further, there was a significant improvement in the body weight of the rabbits at the end of the experiment. The effect of the three probiotics investigated in this trial was found to be related to the sex of the rabbits and to the intake period (duration). Ultimately, these findings raise the possibility of using probiotics to investigate in an in-depth and specific manner based on fixed factors such as the strain, the gender and age of the animals, the main underlying mechanisms and effects, which would allow achieving optimal and adapted health benefits and sustainable production. In the context of animal production, it is worth investigating in a targeted study the effect of the three strains on muscle growth and development and finding evidence of the possible consequences on meat quality traits of the rabbits supplemented with probiotics.

Beneficial effects of Enterococcus faecium EF9a administration in rabbit diet

<p>Forty-eight rabbits aged five weeks (Hycole breed, both sexes) were divided into experimental (EG) and control (CG) groups, 24 animals in each, and fed a commercial diet with access to water <em>ad libitum</em>. Rabbits in EG had Enterococcus faecium EF9a probiotic strain added to their drinking water (1.0×10⁹ colony forming units/mL 500 μL/d/animal) for 28 d (between 35 and 63 d). The experiment lasted for 42 d. The animals remained in good health condition throughout the experiment, and no morbidity and mortality was noted. There was a higher live weight at 63 d of age (+34 g; <em>P</em>&lt;0.0001), final live weight at 77 d of age (+158 g; <em>P</em>=0.0483), and average daily weight gain between 63 and 77 d of age in the EG group rabbits than in CG group rabbits (+8 g/d; <em>P</em>&lt;0.0001). No significant changes in caecal lactic acid and total volatile fatty acid concentrations, jejunal morphological parameters and phagocytic activity were noted during the treatment. The tested serum parameters were within the range of the reference values. EF9a strain sufficiently established itself in the rabbit’s gastrointestinal tract. At 63 d of age, a significant decrease in coliforms (<em>P</em>&lt;0.05), coagulase-positive staphylococci (<em>P</em>&lt;0.01), pseudomonads (<em>P</em>&lt;0.01) and coagulasenegative staphylococci (CoNS, <em>P</em>&lt;0.001) was noted in the faeces of the EG group rabbits compared to the CG rabbits. Antimicrobial effects of EF9a strain in the caecum against coliforms (<em>P</em>&lt;0.001), CoNS (<em>P</em>=0.0002) and pseudomonads (<em>P</em>=0.0603) and in the appendix (coliforms, <em>P</em>&lt;0.05) were detected.</p>

Autochtonous Strain Enterococcus faecium EF2019(CCM7420), Its Bacteriocin and Their Beneficial Effects in Broiler Rabbits-A Review

The present review evaluates and compares the effects achieved after application of rabbit-derived bacteriocin-producing strain Enterococcus faecium CCM7420 with probiotic properties and its bacteriocin Ent7420. The experiments included varying duration of application (14 and 21 days), form of application (fresh culture and lyophilized form), combination with herbal extract and application of the partially purified enterocin-Ent7420, produced by this strain. Results from these studies showed that E. faecium CCM7420 strain was able to colonize the gastrointestinal tract (caecum) of rabbits (in the range < 1.0-6.7 log cycle, respectively 3.66 log cycle on average), to change the composition of intestinal microbiota (increased lactic acid bacteria, reduced counts of coliforms, clostridia and staphylococci), to modulate the immunity (significant increase of phagocytic activity), morphometry (enlargement absorption surface in jejunum, higher villi height:crypt depth (VH:CD) ratio), physiological (serum biochemistry; altered total proteins, glucose and triglycerides levels) and parasitological (Eimeria sp. oocysts) parameters and to improve weight gains (in the range 4.8-22.0%, respectively 11.2% on average), feed conversion ratio and meat quality (physicochemical traits and mineral content).

Some safety aspects of enterococci isolated from Slovak lactic acid dairy product "žinčica"

In Slovakia, dairy products made from ewes' milk have a long tradition. These products include the lactic acid product called "žinčica" which is a by-product occurring during the preparation of ewes' lump cheese. There is no information in the literature regarding the special properties of the microbiota, especially lactic acid Firmicutes, which can survive in "žinčica." From the safety aspect, enterococci are a controversial group of bacteria, and those from "žinčica" have never been tested for their properties. The "žinčica" used in our study was supplied by several different agrofarms producing ewes' lump cheese in central Slovakia. The species Enterococcus faecium (strains EF30E1, EF32E1, EF34E1, EF34E5) and Enterococcus faecalis (strains EE30E4, EE35E1, E31E2, altogether 7) were detected in samples from "žinčica" identified using MALDI-TOF spectrometry with secure genus identification/probable species identification and then confirmed by means of PCR. Enterococci were hemolysis-negative and the genes of the typical enterococcal virulence factors were mostly absent; the gelE gene was found in two E. faecium strains (EF30E1 and EF32E1), the agg gene was detected in E. faecalis EE35E1, and the esp gene was found in two E. faecalis strains (EE30E4 and EE31E2). No strains harbored the cytolysin A gene. Biofilm formation was detected in four strains (EF30E1, EF32E1, EF34E1, and EF34E5), indicating highly positive and low-grade positive biofilm formation. Enterococci were mostly susceptible to antibiotics tested for their phenotype. This is the first study to analyze enterococci in "žinčica."

Sensitivity to Enterocins of Biogenic Amine-Producing Faecal Enterococci from Ostriches and Pheasants

Enterococci are widespread bacteria forming the third largest genus among lactic acid bacteria. Some possess probiotic properties or they can produce beneficial proteinaceous antimicrobial substances called enterocins. On the other hand, some enterococci produce biogenic amines (BAs), so this study is focused on the sensitivity to enterocins of biogenic amine-producing faecal enterococci from ostriches and pheasants. Altogether, 60 enterococci isolated from faeces of ostriches and pheasants were tested for production of BAs. This target of the identified enterococci involved 46 strains selected from 140 ostriches and 17 from 60 pheasants involving the species Enterococcus hirae, E. faecium, E. faecalis, and E. mundtii. Although BAs histamine, cadaverine, putrescine, and tryptamine were not detected in the enterococci tested, in general high BA production by the tested enterococci was noted. The species E. hirae formed the majority of the enterococcal strains from ostrichs faeces (34 strains). High production of tyramine (TYM) was measured with an average amount of 958.16 ± 28.18 mg/ml. Among the enterococci from pheasants, the highest was production of TYM compared to phenylethylamine, spermidine, and spermine. Enterococci featured high BA production; however, they were sensitive to seven enterocins with inhibition activity ranging from 100 up to 25,600 AU/ml.

The Effect of Lactobacillus isolates on growth performance, immune response, intestinal bacterial community composition of growing Rex Rabbits

The objective of this experiment was to investigate the effect of Lactobacillus isolates on intestinal bacterial community composition of growing Rex Rabbits. A total of 120 weaned Rex Rabbits (30 days old, 30 per group) were used for the experiment, which started after an adaptation period of 7 days. The control group was fed with basal diet only, while the treatment I, II and III groups were fed with basal diet adding antibiotics, Lactobacillus zeae (LB1) and Lactobacillus casei (L3) respectively. Growth performance, immune response and intestinal flora have been examined. The results obtained were as follows: (i) F/G of the rabbits fed with Lactobacillus isolates was significantly lower than that of the control group (p < 0.05). (ii) The concentration of ALT decreased significantly (p < 0.05) and that of IgG and IgM increased significantly (p < 0.05) after feeding rabbits with Lactobacillus isolates. (iii) Lactobacillus isolates had no influence on the number of mast cells in duodenum and jejunum, but increased the number of mast cells in caecum significantly (p < 0.05). (iv) The data from pyrosequencing-based analysis suggested that the bacterial community in the rabbit's intestinal flora can be changed by Lactobacillus isolates and antibiotics, especially for the microbial diversity and abundance in the caecum. In conclusion, the application of proper Lactobacillus isolates can improve the growth performance, enhance the immunological function and adjust the intestinal micro-ecosystem of growing Rex Rabbits.

Sensitivity to Enterocins of Thermophilic Campylobacter spp. from Different Poultry Species

Campylobacter spp. have been isolated from various animals, including poultry. They are rapidly transmitted throughout broiler sheds by the fecal-oral route. A promising strategy to reduce Campylobacter spp. in poultry may be done due to the beneficial properties of probiotic bacteria and their bacteriocins. In this study, inhibition spectrum/activity of different enterocins was evaluated against Campylobacter spp. (isolated from different poultry) to indicate further practical use of enterocins. Enterocins are antimicrobial proteinaceous substances produced mostly by enterococci. Feces from broiler chickens (10), laying hens (47), ostriches (140), and ducks (40) were screened. Altogether, 23 strains were allotted to the species Campylobacter jejuni and Campylobacter coli using MALDI TOF mass spectrometry and confirmed by genotyping (PCR method). In the feces of ostriches, Campylobacter spp. were not confirmed. Campylobacter spp. isolated from different poultry showed resistance to nalidixic acid, ciprofloxacin, and ampicillin. Interestingly, strains demonstrating antibiotic resistance revealed sensitivity to at least one of the nine enterocins used (except C. coli Kc1, SZ3, and C. jejuni 1/D). Almost 52% strains were inhibited by Ent A (P). Enterocins can therefore be used to prevent or reduce Campylobacter spp.; it is a basis for practical use.

Staphylococci Related to Farm Ostriches and Their Sensitivity to Enterocins

In Slovakia, ostriches are reared mainly for their meat. There is still limited information related to microflora of ostriches, including staphylococci. Knowing the composition of microflora is very important for the recognition of potential pathogenic agents. Recently, a frequent problem in animals is the occurrence of bacteria resistant to antibiotics. The aim of this study was to detect staphylococcal species in feces of farm ostriches and to test their sensitivity to antibiotics and enterocins. Altogether 140 ostriches from three age groups were sampled (n = 18, faecal mixture samples from each group) on a farm in Slovakia or on Slovak farm. From 54 fecal samples, the staphylococcal count reached an average 4. 3 ± 0. 63 (log10) CFU/g. Twenty-four lactic acid producing strains were taxonomically classified to eight species of the genus Staphylococcus: Staphylococcus equorum, S. xylosus, S. epidermidis, S. haemolyticus, S. cohnii, S. succinus, S. warneri, and S. hominis. Strains were evaluated by secure probable species identification/probable species identification (score value up to 2.299) confirmed also by phenotypization. Most strains were sensitive to antibiotics. Four strains (S. haemolyticus SHae 111, S. haemolyticus SHAe 371, S. xylosus SX 2133, and S. warneri SW 292) were resistant to methicillin but sensitive to six or five of the seven enterocins tested (inhibitory activity 200-12,800 AU/mL). S. warneri SW 292 was sensitive to all enterocins (activity up to 12,800 AU/mL).

Enterococci isolated from farm ostriches and their relation to enterocins

The present study focuses on the detection of enterococci in ostrich faeces. Forty-six bacterial colonies from 140 ostriches were identified at the species level using the MALDI-TOF MS identification system. According to the score value evaluation, they were allotted to the species Enterococcus hirae, Enterococcus faecium and Enterococcus mundtii confirmed also by phenotypic testing. Dominated species E. hirae (34 strains) were submitted to more detailed testing. Those strains E. hirae produced either no or only slight amount of the enzymes related to disorders (N-acetyl-β-glucosaminidase, β-glucuronidase, α-chymotrypsin, trypsin). Most of the strains were not hemolytic. They did not harbour the hiracin-producing gene. Five E. hirae strains harboured virulence factor gene gelE; however, they were phenotypically gelatinase negative. They also harboured other virulence factor genes such as esp, efaAfm and ccf. E. hirae strains were mostly sensitive to antibiotics and those resistant at least to one antibiotic were sensitive to enterocins (200-25,600 AU/mL). This study represents original and novel results concerning the enterococcal microflora in ostriches; enterococci in ostriches have not been described in detail up to now; sensitivity to enterocins of E. hirae strains harbouring virulence factor genes to enterocins is also new.