Enterocin M and Sage Supplementation in Post-weaning Rabbits: Effects on Growth Performance, Caecal Microbiota, Fermentation and Enzymatic Activity

Lactic acid bacteria reduce bacterial diarrhea in rabbits via enhancing immune function and restoring intestinal microbiota homeostasis

BACKGROUND

Numerous previous reports have demonstrated the efficacy of Lactic acid bacteria (LAB) in promoting growth and preventing disease in animals. In this study, Enterococcus faecium ZJUIDS-R1 and Ligilactobaciiius animalis ZJUIDS-R2 were isolated from the feces of healthy rabbits, and both strains showed good probiotic properties in vitro. Two strains (108CFU/ml/kg/day) were fed to weaned rabbits for 21 days, after which specific bacterial infection was induced to investigate the effects of the strains on bacterial diarrhea in the rabbits.

RESULTS

Our data showed that Enterococcus faecium ZJUIDS-R1 and Ligilactobaciiius animalis ZJUIDS-R2 interventions reduced the incidence of diarrhea and systemic inflammatory response, alleviated intestinal damage and increased antibody levels in animals. In addition, Enterococcus faecium ZJUIDS-R1 restored the flora abundance of Ruminococcaceae1. Ligilactobaciiius animalis ZJUIDS-R2 up-regulated the flora abundance of Adlercreutzia and Candidatus Saccharimonas. Both down-regulated the flora abundance of Shuttleworthia and Barnesiella to restore intestinal flora balance, thereby increasing intestinal short-chain fatty acid content.

CONCLUSIONS

These findings suggest that Enterococcus faecium ZJUIDS-R1 and Ligilactobaciiius animalis ZJUIDS-R2 were able to improve intestinal immunity, produce organic acids and regulate the balance of intestinal flora to enhance disease resistance and alleviate diarrhea-related diseases in weanling rabbits.

Evaluating the effects of tannic acid on rabbit growth performance, digestibility, antioxidant status, intestinal morphology and caecal fermentation and microbiota

The objective of this study was to assess the effects of dietary supplementation with tannic acid (TA) on the growth performance, digestibility, antioxidant status, intestinal morphology and the caecal fermentation and microbiota in rabbits. A total number of 120 Ira rabbits (30 days of age) were randomly allotted to four dietary treatment groups: TA 0 (control), TA 0.75, TA 1.5 and TA 3, administered basal diets with 0, 0.75, 1.5 and 3 g TA/kg of feed for 28 days. Compared to the control group, dietary 3 g TA/kg inclusion decreased the average daily feed intake (p < 0.05). No significant differences were found in the digestibility among the groups (p > 0.05). Serum total antioxidant capacity was significantly higher in the 3 g/kg TA group than in the other groups (p < 0.05). There was a significant increase in the concentration of propionic acid and butyric acid in the 3 g/kg TA group. The addition of TA had no effect on villus height and crypt depth of small intestine (p > 0.05). The 16S rRNA high-throughput sequencing results showed that at the phylum level, dietary 3 g/kg TA increased the abundance of Bacteroidetes in the caecum of rabbits (p < 0.05). Based on the results, dietary TA is effective in antioxidant capacity of rabbits, improving caecal fermentation and optimizing the caecal microflora. However, the appropriate dosage supplementation of TA in rabbits needs further research.

Effect of Diet Supplementation with Enterococcus Durans ED26E/7 and its Durancin ED26E/7 on Growth Performance, Caecal Enzymatic Activity, Jejunal Morphology and Meat Properties of Broiler Rabbits

The present study investigates the effects of Enterococcus durans ED26E/7 beneficial strain and its enterocin – durancin (Ent) ED26E/7 on selected parameters in rabbits: growth performance, caecal enzymatic activity, jejunal morphometry and meat physico-chemical characteristics. Seventytwo rabbits (aged five weeks, M91 meat line, both sexes) were divided into experimental groups E1 (E. durans ED26E/7 strain; dose 500 μL/animal/day, concentration 109 CFU/mL) and E2 (durancin EntED26E/7; dose 50 μL/animal/day, with activity 12 800 AU/mL) and control group (C). The additives were administered in drinking water for a period of 21 days. All animals remained in good health during the experiment. The highest body weight gain (increase by 1.5% compared to C) was noted in E1 group during ED26E/7 strain application (P<0.001). Both bioactive compounds positively influenced (reduced) the feed conversion ratio (P<0.001). The ED26E/7 strain and its EntED26E/7 application stimulated the activity of most enzymes tested in the caecum; only the amylolytic and inulolytic activity in E2 group decreased during durancin ED26E/7 addition. Both additives, but mainly the ED26E/7 strain, showed a tendency to improve the jejunal morhological parameters till the end of the experiment (day 42). The meat physico-chemical parameters were not negatively influenced by the application of E. durans ED26E/7 strain and its durancin ED26E/7. The diet supplementation with bacteriocinogenic and probiotic E. durans ED26E/7 strain and its EntED26E/7 may improve the growth performance, caecal enzymatic activity and jejunal morphometry of rabbits, without any negative effect on rabbit meat quality.

Isolation, identification, and biological characteristics of Clostridium sartagoforme from rabbit

In order to develop microbial additives for rabbit feed, a spore-forming bacteria was isolated from the feces of Hyla rabbit using reinforced clostridium medium (RCM). The 16S rDNA sequence of the bacterium was subjected to pairwise sequence alignment using BLAST; the colony morphology, and physiological, biochemical, and stress resistance were studied. The results showed that the bacterium was Clostridium sartagoforme, a gram positive anaerobe, which can produce spores. The colony diameter was 0.5 mm—2.5 mm, the diameter of the bacteria was 0.5 μm—1.0 μm × 2.0 μm—6.3 μm, and the spore diameter was 1 μm—1.2 μm × 1 μm—1.2 μm. C. sartagoforme can utilize various sugars and alcohols such as fructose, galactose, sorbitol, and inositol. It secreted cellulase into the extracellular environment to form a transparent hydrolysis circle in Congo red medium, it could not liquify gelatin, and the lysine decarboxylase reaction was positive. In liquid medium it entered the stable growth period after 9 h of inoculation. Additionally, it had good stress resistance with a survival rate that exceeded 53% after gastric juice (pH 2.5) treatment for 3 h, it grew in a medium with a bile salt concentration of 0.3%, and the survival rate exceeded 85% after 10 minutes at 80°C. Moreover, animal testing indicated that this strain has no adverse effects on the morbidity and mortality of rabbits. In summary, C. sartagoforme XN-T4 was isolated from rabbit feces. This bacterium has good resistance to stress, can decompose a variety of monosaccharides and polysaccharides including cellulose, which is relatively harmless for animal health.

Enterocins as Novel Feed Additives in Rabbit Diet: Enterocin Ent M and Durancin Ent ED26E/7, Their Combination, and Effects on Microbiota, Caecal Fermentation, and Enzymatic Activity

The present study investigates the effects of enterocin Ent M and durancin Ent ED26E/7 applied separately and in combination on the intestinal microbiota, caecal enzymatic activity, and fermentaion of rabbits. Eighty rabbits (M91 meatline, aged 5 weeks, both sexes) were divided into groups E (Ent M; 50 µL/animal/day), D (Ent ED26E/7; 50 µL/animal/day), E + D (Ent M + Ent ED26E/7), and control (C). The additives were administered in drinking water for 21 days. Antimicrobial activity of Ent M and Ent ED26E/7 on coliforms (E, E + D: P < 0.001) and pseudomonads (D: P < 0.05) in feces was noted, compared to C. Ent M and Ent ED26E/7 application stimulated caecal enzymatic activity in rabbits. Pectinolytic (E vs. D, E + D: P < 0.01), inulolytic (E vs. E + D: P < 0.01; E vs. C: P < 0.05), and amylolytic (E vs. D, E + D. P < 0.001; E vs. C: P < 0.01) activities were influenced by Ent M, while cellulolytic (D vs. E + D: P < 0.01) and inulolytic (D vs. E + D, C: P < 0.01) activities by Ent ED26E/7 treatment. The cellulolytic and pectinolytic acitivities changed with time. Treatment × time interaction was detected for cellulose and xylan degradation. During Ent M and Ent ED26E/7 treatment, increased ammonia, lactic, butyric and iso-valeric acid, and lower acetic, propionic, iso-butyric, valeric, and caproic acid concentrations were noted. It can be concluded that Ent M and Ent ED26E/7 application can improve rabbit health due to reduced spoilage microbiota and enhanced caecal enzymatic activity.

Effect of enterocin M and durancin ED26E/7 supplementation on blood parameters, immune response and jejunal morphometry in rabbits

Natural feed additives application in rabbit nutrition can help to control and prevent digestive disturbances and improve gut health and immunity around the critical weaning period. While probiotics are frequently used in rabbits, in vivo administration of bacteriocins is often limited. Therefore, the present study evaluates the effect of enterocin EntM, durancin EntED26E/7 and their combination on serum biochemistry, phagocytic activity and jejunal morphometry of rabbits. Eighty rabbits (aged 35 days, meat line M91, both sexes) were divided into experimental groups E (EntM; dose 50 µl/animal/day, activity 25,600 AU/ml), D (EntED26E/7; 50 µl/animal/day, 12,800 AU/ml), E + D (50 µl EntM + 50 µl EntED26E/7 /animal/day) and control group (C). Additives were administrated in drinking water for 21 days. Both enterocins positively influenced tested serum parameters, with emphasis on durancin EntED26E/7 administration, alone and/or in combination with EntM. Increased total proteins (E, D: p < 0.001), urea (D: p < 0.001), albumin (D: p < 0.05) and triglycerids (E, D, E+D: p < 0.001) were found. Hypocholesterolaemic effect of both additives was recorded (p < 0.001), with the lowest HDL concentration in E + D. The most of tested hepatic enzymes were positively influenced by enterocins combination (E + D; p < 0.001). The lowest AST was noted in group D (p < 0.001). Mineral profile was also improved (p < 0.001), with the highest values in D. Oxidative stress, was not evoked during enterocins application. Both additives showed a tendency to improve phagocytic activity (prolonged effect of EntED26D/7; D, E+D: p < 0.05) and jejunal morphometry parameters (increased villus cut surface; E, D, E+D; p < 0.001). Diet supplementation with EntM and mostly with EntED26E/7 can improve serum biochemistry, phagocytic activity and jejunal morphometry.

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).

Can Enterocin M in Combination with Sage Extract Have Beneficial Effect on Microbiota, Blood Biochemistry, Phagocytic Activity and Jejunal Morphometry in Broiler Rabbits?

Simple Summary

The weaning period is one of the most critical phases in a rabbit’s life, when rabbits are most sensitive to various spoilage agents, often with fatal outcome. Preventing these post-weaning alimentary disturbances and improving gut health through the use of natural substances has become an area of research activity in rabbit nutrition. The possibilities of “in vivo” administration of bacteriocins in rabbits are often limited. Our study focused therefore on improving rabbits’ health using enterocin M and sage extract, alone and also in combination, mainly to determine their effect on the microbiota, phagocytic activity, serum biochemistry, and morphometry of rabbits. The antibacterial effect of both additives was observed in the gastrointestinal tract of rabbits. Several biochemical parameters (increased in total proteins (TPs) using enterocin (Ent) M, reduction of alanine aminotransferase (ALT) using sage and its hypocholesteremic effect alone and in combination with EntM, and improvement of mineral levels) were optimized. All additives, but mostly EntM, showed a tendency to improve the jejunal morphological parameters.

Abstract

The present study investigated the effects of enterocin (Ent) M and sage extract alone and also in combination on the gut microflora, phagocytic activity, blood biochemistry, and morphometry of rabbits. Sixty-four rabbits (aged five weeks, M91 meatline, both sexes) were divided into three experimental groups: E (EntM; 50 µL/animal/day), S (sage; 10 µL/animal/day), and E + S (EntM + sage) groups and control group (C). The additives were administered in drinking water for a period of 21 days. Dietary supplementation of EntM and sage significantly reduced the coliforms (E: p < 0.001; S: p < 0.001; E + S: p < 0.001) in feces, while simultaneous addition of EntM and sage decreased enterococci (E + S: p < 0.0001), lactic acid bacteria (E + S: p < 0.01), and coagulase-positive staphylococci (E + S: p < 0.0001) in the appendix. Sage addition reduced HDL (S: p < 0.001) and LDL cholesterol (S: p < 0.001; E + S: p < 0.001), LDL/HDL ratio (S: p < 0.001; E + S: p < 0.01), and increased urea (S: p < 0.01; E + S: p < 0.001) and creatinine (S: p < 0.001; E + S: p < 0.001) in serum. EntM and sage application, alone or in combination, improve the jejunal morphometry (p < 0.0001) in rabbits.