Effects of Enterococcus faecium SLB 120 on growth performance, blood parameters, relative organ weight, breast muscle meat quality, excreta microbiota shedding, and noxious gas emission in broilers

Short-term supplementation with uncoated and encapsulated Enterococcus faecium affected growth performance, gut microbiome and intestinal barrier integrity in broiler chickens

Enterococcus faecium (E. faecium) is an alternative to antibiotics, while the probiotic effect of short-term application in mature broiler chickens remains unclear. In the current study, 48 Arbor Acres male broilers were chosen to investigate the effects of E. faecium on growth performance, the gut microbiome and intestinal health during the finishing period. Forty-eight birds were randomly allocated to 4 treatment groups that were fed a corn-soybean meal basal diet (Con), a basal diet supplemented with 1 g/kg amoxicillin (ABX), 5×106 CFU/g encapsulated E. faecium (cEF), or 5×106 CFU/g uncoated E. faecium (EF) from d 33 to 42. The results showed that 10 d of antibiotic treatment decreased the growth performance of the broilers (P < 0.05). The feed conversion ratio of the cEF and EF groups were lower than that of the Con group by 0.13 and 0.07, respectively (P > 0.05). The abundance of viable ileal and cecal E. faecium in the cEF group was greater than that in the EF group (P < 0.05), and both groups were markedly greater than those in the Con and ABX groups (P < 0.05). The ABX treatment decreased the Shannon and Chao1 indices of the cecal microbiota, while the dietary E. faecium treatment resulted in significant differences in the β diversity of the ileal and cecal microbiota (P < 0.05). Mantel correlation revealed that the ileal microbiota at the genus level was significantly correlated with the growth performance of broilers, with Lactobacillus, Bacillus and Escherichia-Shigella showing positive and strong correlations (P < 0.05). In the ileum, the crypt depth was lower in the cEF group than in the Con group, but the villi height-to-crypt depth ratio was greater in the cEF group than in the other groups (P = 0.037). However, the expression of the ZO-2 and Occludin genes was downregulated in the E. faecium-fed birds (P < 0.05). In the cecum, the acetate, butyrate and total SCFA levels were greater in the EF group (P < 0.05), while the propionate, isobutyrate and isovalerate levels were lower in the ABX group (P < 0.05). In summary, 10 d of dietary supplementation with E. faecium markedly increased colonization in mature broilers and potentially improved growth performance by modulating the ileal microbiota. Encapsulation techniques could enable a slow release of E. faecium in the intestine, thereby reducing the negative impacts of rapid expansion of E. faecium on the intestinal epithelium.

Meta-analysis to predict the effects of probiotics on meat quality of broiler

The demand for chicken meat has surged globally due to its status as a primary protein source in human diets. However, ensuring high-quality meat products has become an increasingly important subject to consumers. In this study, 21 articles from PubMed and Web of Science databases published between 2005 and 2023 were examined to assess the influence of probiotic supplementation on broiler meat quality. The meta-analysis revealed significant findings across various meat quality parameters. Specifically, probiotics were found to significantly affect meat colour parameters, including redness, yellowness, and lightness, in both breast and thigh meat samples. Moreover, significant differences were observed in parameters such as water-holding capacity (p < 0.001), cook loss (p = 0.047), and shear force (p = 0.025) between control and probiotic groups. However, it's essential to note the considerable heterogeneity among the studies, emphasising the need for a cautious interpretation of the results. Despite this variability, the study underscores the potential of probiotics to positively influence broiler meat quality, highlighting avenues for further research and standardisation in poultry production practices. These findings also contribute to a better understanding of probiotics' role in improving meat quality and meeting consumer preferences for nutritious and high-quality poultry products.

Effects of Supplementing Drinking Water of Parental Pigeons with Enterococcus faecium and Bacillus subtilis on Antibody Levels and Microbiomes in Squabs

Enterococcus faecium (E. faecium) and Bacillus subtilis (B. subtilis) are widely used as probiotics to improve performance in animal production, but there have been few reports of their impacts on pigeon milk. In this study, twenty-four pairs of parental pigeons were randomly divided into four groups, with six replicates, and each pair feeding three squabs. The control group drank normal water. The E. faecium group, B. subtilis group, and mixed group drank water supplemented with 3 × 106 CFU/mL E. faecium, 2 × 107 CFU/mL B. subtilis, and a mixture of these two probiotics, respectively. The experiment lasted 19 days. The results demonstrated that the IgA and IgG levels were significantly higher in the milk of Group D pigeons than in the other groups. At the phylum level, Fimicutes, Actinobacteria, and Bacteroidetes were the three main phyla identified. At the genus level, Lactobacillus, Bifidobacterium, Veillonella, and Enterococcus were the four main genera identified. In conclusion, drinking water supplemented with E. faecium and B. subtilis could improve immunoglobulin levels in pigeon milk, and this could increase the ability of squabs to resist disease. E. faecium and B. subtilis could be used as probiotics in the pigeon industry.

Evaluation of the Efficacy of Enterococcus faecium L3 as a Feed Probiotic Additive in Chicken

The study was devoted to the comparison of the probiotic effect of enterococcal Enterococcus faecium L3 to the antibiotic enramycin as a chicken feed additive. Two hundred and sixteen chickens were divided into three groups and tested by different parameters including weight gain, food consumption, blood biochemistry, immunology, and caecal microbiome at two checkpoints, 21 and 39 days after birth. By the end of the experiment, a group of chickens getting probiotic demonstrated weight gain of more than 100 g at the average relative to the control group with no additive in animal feed (P < 0.05). Blood serum biochemistry showed a significant increase in HDL level (P < 0.05) relative to the control group. The 16S RNA sequencing demonstrated the growth abundance of Lachnospiraceae and the decrease of Proteobacteria in probiotic fed group. On the contrary, the antibiotic fed group showed a noticeable increase in the abundance of Proteobacteria which included the genus Salmonella. Thus, probiotic E. faecium L3 being added to chicken food as a single additive may be considered as a possible replacement of antibiotic enramycin.

Recent innovations in various methods of harmful gases conversion and its mechanism in poultry farms

Poultry breeding takes place in intensive, high-production systems characterized by high animal density, which is a source of harmful emission of odorous volatile organic compounds (VOCs), ammonia (NH3), hydrogen sulfide (H2S) and greenhouse gases, which in turn sustain animal welfare. This study identified and examined the characteristics of chemical compounds emitted in intensive poultry farming (laying hens, broilers) and their toxicity, which led to recommending methods of deodorization. Emphasis was placed on the law relative to air purification in poultry farms. Various methods of air treatment in poultry farms have been described: the modification of animal diet to improve nutrient retention and decrease the amount of their excrement; chemical oxidation technologies (ozonation, photocatalysis, Fenton reaction); various types/brands of biofilters, bioscrubbers and membrane reactors. Numerous studies show that biofilters can reduce ammonia emissions by 51%, hydrogen sulfide by 80%, odors by 67%, while scrubbers brings down ammonia emissions by 77% and odors by 42%, and the application of UV light lowers ammonia emissions by 28%, hydrogen sulfide by 55%, odors by 69% and VOCs by 52%. The paper presents both the solutions currently used in poultry farming and those which are currently in the research and development phase and, as innovative solutions, could be implemented in the near future.

Pretreatment with probiotics Enterococcus faecium NCIMB 11181 attenuated Salmonella Typhimurium-induced gut injury through modulating intestinal microbiome and immune responses with barrier function in broiler chickens

Background

Preventing Salmonella infection and colonization in young birds is key to improving poultry gut health and reducing Salmonella contamination of poultry products and decreasing salmonellosis for human consumption (poultry meat and eggs). Probiotics can improve poultry health. The present study was conducted to investigate the impact of a probiotics, Enterococcus faecium NCIMB 11181 (E. faecium NCIMB 11181) on the intestinal mucosal immune responses, microbiome and barrier function in the presence or absence of Salmonella Typhimurium (S. Typhimurium, ST) infection.

Methods

Two hundred and forty 1-day-old Salmonella-free male broiler chickens (Arbor Acres AA⁺) were randomly allocated to four groups with 6 replicate cages of 10 birds each. The four experimental groups were follows: (1) negative control (NC), (2) S. Typhimurium, challenged positive control (PC), (3) the E. faecium NCIMB 11181-treated group (EF), (4) the E. faecium NCIMB 11181-treated and S. Typhimurium-challenged group (PEF).

Results

Results indicated that, although continuous feeding E. faecium NCIMB 11181 did not obviously alleviate growth depression caused by S. Typhimurium challenge (P > 0.05), E. faecium NCIMB 11181 addition significantly blocked Salmonella intestinal colonization and translocation (P < 0.05). Moreover, supplemental E. faecium NCIMB 11181 to the infected chickens remarkably attenuated gut morphological structure damage and intestinal cell apoptosis induced by S. Typhimurium infection, as evidenced by increasing gut villous height and reducing intestinal TUNEL-positive cell numbers (P < 0.05). Also, E. faecium NCIMB 11181 administration notably promoting the production of anti-Salmonella antibodies in intestinal mucosa and serum of the infected birds (P < 0.05). Additionally, 16S rRNA sequencing analysis revealed that E. faecium NCIMB 11181 supplementation ameliorated S. Typhimurium infection-induced gut microbial dysbiosis by enriching Lachnospiracease and Alistipes levels, and suppressing Barnesiella abundance. Predicted function analysis indicated that the functional genes of cecal microbiome involved in C5-branched dibasic acid metabolism; valine, leucine and isoleucine biosynthesis; glycerolipid metabolism and lysine biosynthesis were enriched in the infected chickens given E. faecium NCIMB 11181. While alanine, asparate and glutamate metabolism; MAPK signal pathway-yeast; ubiquine and other terpenoid-quinore biosynthesis, protein processing in endoplasmic reticulum; as well as glutathione metabolism were suppressed by E. faecium NCIMB 11181 addition.

Conclusion

Collectively, our data suggested that dietary E. faecium NCIBM 11181 supplementation could ameliorate S. Typhimurium infection-induced gut injury in broiler chickens. Our findings also suggest that E. faecium NCIMB 11181 may serve as an effective non-antibiotic feed additive for improving gut health and controlling Salmonella infection in broiler chickens.

Effects of the Probiotic Candidate E. faecalis-1, the Poulvac E. coli Vaccine, and their Combination on Growth Performance, Caecal Microbial Composition, Immune Response, and Protection against E. coli O78 Challenge in Broiler Chickens

The present study was performed on 180-day-old commercial Cobb chicks to assess the effects of the probiotic candidate Enterococcus faecalis-1, the Poulvac Escherichia coli vaccine, and their combination on growth parameters, intestinal microbial composition, immune response, and protection against challenge with the avian pathogen E. coli O78. The experimental groups were as follows: G1, basal diet; G2, basal diet and challenge with O78 at 28 days of growth; G3, basal diet, vaccination with Poulvac (1 and 15 days), and challenge with O78 at 28 days of growth; G4, basal diet, E. faecalis-1 supplementation for the first 3 days of growth, and challenge with O78 at 28 days of growth; G5, basal diet, E. faecalis-1 supplementation for the first 3 days of growth, vaccination with Poulvac (1 and 15 days), and challenge with O78 at 28 days of growth; G6, basal diet and E. faecalis-1 supplementation for the first 3 days of growth. The results showed that E. faecalis-1 in drinking water significantly improved the growth performance and immune response, increased the total Enterococcus counts, reduced the mortality, and decreased the visceral invasion by O78 in challenged broilers. While the effect of the Poulvac vaccine alone or with E. faecalis-1 was not significant compared with that of the E. faecalis-1 supplement, the vaccine improved the growth rate and decreased the mortality and visceral invasion by APEC O78 in challenged broilers. These results showed that E. faecalis-1 supplementation and routine vaccination with the Poulvac vaccine could improve the growth performance and immune response of broiler chickens and protect against challenge with APEC O78.

Effect of Age on the Immune and Visceral Organ Weights and Cecal Traits in Modern Broilers

Simple Summary

Currently, due to the high developments achieved in the poultry industry especially in genetics, management, nutrition, health, and animal welfare, modern broilers reach slaughter weight at an earlier age, which in turn has brought about notable changes in the morphophysiology of these birds. The following research proposes to determine the effect of age on visceral and immune organ weight, cecal pH, and cecal lactic acid bacteria in Ross 308^® broilers, up to 10 days old. It was concluded that the immune and visceral organs increase their absolute and relative weight according to age and on days 9 and 10 the highest growth rate of the organs was found, furthermore, the colonization of the cecal lactic acid bacteria is established before 10 days of life (as the most critical stage), although with variable changes for intestinal pH. The correlation showed, in addition, a significant association between the organs evaluated, as well as for the cecum relative weight and the cecal lactic bacteria count. These results could contribute to updating knowledge on immunological activity, cecal microbiology, and the functioning of the digestive system, as well as for the development of new nutritional requirements and the optimization of dietary formulations.

Abstract

This study aimed to determine the effect of age on the immune and visceral organ weights and cecal traits in modern broilers. 200 male Ross^® 308 broilers were randomly selected, then 20 broilers were slaughtered every day (up to 10 days old) after six hours of fasting. All the organs measured had a progressive increase in absolute weight as the days progressed, apart from the spleen, which decreased its absolute weight on day 5, even though on day 10 it showed the highest values. Moreover, the small intestine relative weight increased from the fourth to the ninth day and was correlated (p ≤ 0.05) with the relative weight of the proventriculus, gizzard, small intestine, and cecum, although without statistical association with the of the heart. There was a correlation between the cecum relative weight and the cecal lactic acid bacteria, and between the primary lymphoid organs. The pH (from 5.74 to 7.40) and cecal lactic acid bacteria (from 6.11 to 8.79 log 10 CFU/g) changed according to the age of the broilers. The results could contribute to the understanding of the physiology and intestinal microbiology of the first 10 days old of modern broilers, which is crucial to improve the genetic expression of these animals.

The effects of lactic acid bacteria and yeasts as probiotics on the growth performance, relative organ weight, blood parameters, and immune responses of broiler: A meta-analysis

Introduction: The number of publications in Scopus on this topic increased from less than 50 in 1995 to more than 250 in 2015. In other hand, Inconsistency in results about the correlation between yeast and lactic acid bacteria as probiotics has been evident since the early publications on use in broilers. Methods: A meta-analysis was conducted to determine relationship between lactic acid bacteria and yeast as probiotics to broiler diets on the growth performance, relative organ weight, blood parameters, and immune response of the broiler.  A database was designed based on published data that reported the use of probiotics on the broiler. The method used for selecting articles was based on the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) method. Articles selected were taken from PubMed, Web of science, Scopus, Google Scholar, and Science direct databases as well as individual. Results: The final database consists of 49 in vivo articles, 93 studies, and 225 treatments. The analysis statement in the system was a PROC MIXED procedure of SAS software. The level of probiotic increased (p <0.001) body weight, body weight gain, and feed intake of broiler. There was a reduction (p <0.01) on feed conversion ratio and mortality on the level probiotic given to broiler. Supplementation of probiotics in broiler diet increased (p <0.001) the weight of liver, spleen, gizzard, bursa of fabricius and carcass yield, while reduced (p<0.001) abdominal fat weight. The probiotic given increased the total of red and white blood cells (both at p < 0.001) but did not affect lymphocyte.  Discussion: It can be concluded the yeast act as supporting agent that serves lactic acid bacteria as probiotic increases the growth performance, relative organ weight, blood parameters, and immune response of the broiler.

The effects of lactic acid bacteria and yeasts as probiotics on the growth performance, relative organ weight, blood parameters, and immune responses of broiler: A meta-analysis

Introduction: The number of publications in Scopus on this topic increased from less than 50 in 1995 to more than 250 in 2015. In other hand, inconsistency in results about the correlation between yeast and lactic acid bacteria as probiotics has been evident since the early publications on use in broilers. Methods: A meta-analysis was conducted to determine relationship between lactic acid bacteria and yeast as probiotics to broiler diets on the growth performance, relative organ weight, blood parameters, and immune response of the broiler.  A database was designed based on published data that reported the use of probiotics on the broiler. The method used for selecting articles was based on the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) method. Articles selected were taken from PubMed, Web of science, Scopus, Google Scholar, and Science direct databases as well as individual. Results: The final database consists of 49 in vivo articles, 93 studies, and 225 treatments. The analysis statement in the system was a PROC MIXED procedure of SAS software. The level of probiotic increased (p <0.001) body weight, body weight gain, and feed intake of broiler. There was a reduction (p <0.01) on feed conversion ratio and mortality on the level probiotic given to broiler. Supplementation of probiotics in broiler diet increased (p <0.001) the weight of liver, spleen, gizzard, bursa of fabricius and carcass yield, while reduced (p<0.001) abdominal fat weight. The probiotic given increased the total of red and white blood cells (both at p < 0.001) but did not affect lymphocyte.  Discussion: It can be concluded the yeast act as supporting agent that serves lactic acid bacteria as probiotic increases the growth performance, relative organ weight, blood parameters, and immune response of the broiler.

The effects of lactic acid bacteria and yeasts as probiotics on the growth performance, relative organ weight, blood parameters, and immune responses of broiler: A meta-analysis

Introduction: The number of publications in Scopus on this topic increased from less than 50 in 1995 to more than 250 in 2015. In other hand, inconsistency in results about the correlation between yeast and lactic acid bacteria as probiotics has been evident since the early publications on use in broilers. Methods: A meta-analysis was conducted to determine relationship between lactic acid bacteria and yeast as probiotics to broiler diets on the growth performance, relative organ weight, blood parameters, and immune response of the broiler.  A database was designed based on published data that reported the use of probiotics on the broiler. The method used for selecting articles was based on the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) method. Articles selected were taken from PubMed, Web of science, Scopus, Google Scholar, and Science direct databases as well as individual. Results: The final database consists of 49 in vivo articles, 93 studies, and 225 treatments. The analysis statement in the system was a PROC MIXED procedure of SAS software. The level of probiotic increased (p <0.001) body weight, body weight gain, and feed intake of broiler. There was a reduction (p <0.01) on feed conversion ratio and mortality on the level probiotic given to broiler. Supplementation of probiotics in broiler diet increased (p <0.001) the weight of liver, spleen, gizzard, bursa of fabricius and carcass yield, while reduced (p<0.001) abdominal fat weight. The probiotic given increased the total of red and white blood cells (both at p < 0.001) but did not affect lymphocyte.  Discussion: It can be concluded the yeast act as supporting agent that serves lactic acid bacteria as probiotic increases the growth performance, relative organ weight, blood parameters, and immune response of the broiler.

Effects of chitosan oligosaccharides on meat quality, muscle energy metabolism and anti-oxidant status in broilers that have experienced transport stress

Context Pre-slaughter transport, exposed broilers to various stressors, which resulted in detrimental effects on animal welfare, live bodyweight loss, mortality and meat quality. There was growing interest to explore effective ways to reduce the stress response and improve meat quality of transported broilers by using dietary feed additives. Aims The purpose of the present study was to investigate the effect of chitosan oligosaccharides (COS) on meat quality, muscle energy metabolism and anti-oxidant status of broilers having 3-h transport stress. Methods In total, of 144 35-day-old broilers were randomly allocated to two dietary treatments, including a basal diet (96 broilers), or basal diet supplemented with COS at 200 mg/kg (48 broilers). There were eight broilers per cage, and 12 replication cages in the basal diet group and six replication cages in the basal diet with 200 mg/kg COS group. At the end of the experiment, after a 12-h fast, broilers in the basal diet group were randomly divided into two groups, with six replication cages in each group; then, the broilers were transported as per the following protocols: broilers in the basal diet group (CON group) were without transport stress; broilers in the basal diet group with 3 h of transport stress (TS group), and broilers in the basal diet with 200 mg/kg COS supplementation and 3 h of transport stress (TSC group). The serum corticosterone concentration, serum, liver and muscle anti-oxidant status, as well as meat quality and muscle energy metabolism were analysed. Key results Compared with the CON group, TS group showed increased bodyweight loss, serum corticosterone concentration, breakdown of muscle glycogen, increased muscle lactate dehydrogenase activity, as well as some changes of body anti-oxidant status (higher serum, liver and muscle MDA concentrations, lower serum SOD and GSH-Px, liver SOD and CAT, and lower muscle SOD, GSH-Px, and CAT activity), accompanied with lower pH45min and pH24h. Nevertheless, compared with the TS group, dietary COS supplementation reduced bodyweight loss, decreased muscle MDA concentration, increased muscle SOD and CAT activity, and was accompanied with improving pH24h. Conclusions The results suggested that the positive effects of dietary COS supplementation in maintaining meat quality were mainly due to the improved muscle anti-oxidant status. Implications Dietary supplementation with 200 mg/kg COS could serve as a beneficial and effective way to alleviate transport-impaired meat quality of broilers.

Crosstalk between the growth hormone/insulin-like growth factor-1 axis and the gut microbiome: A new frontier for microbial endocrinology

Both the GH/IGF-1 axis and the gut microbiota independently play an important role in host growth, metabolism, and intestinal homeostasis. Inversely, abnormalities in GH action and microbial dysbiosis (or a lack of diversity) in the gut have been implicated in restricted growth, metabolic disorders (such as chronic undernutrition, anorexia nervosa, obesity, and diabetes), and intestinal dysfunction (such as pediatric Crohn's disease, colonic polyps, and colon cancer). Over the last decade, studies have demonstrated that the microbial impact on growth may be mediated through the GH/IGF-1 axis, pointing toward a potential relationship between GH and the gut microbiota. This review covers current research on the GH/IGF-1 axis and the gut microbiome and its influence on overall host growth, metabolism, and intestinal health, proposing a bidirectional relationship between GH and the gut microbiome.

Growth performance, nutrient digestibility, antioxidant enzyme activity, and fecal microbial flora in growing pigs fed diets containing Spirulina

The present experiment was to evaluate the effects of dietary Spirulina (SP) supplementation in growing pigs. A total of 140 pigs [(Landrace × Yorkshire) × Duroc, 25.32 ± 1.36 kg] were randomly distributed to one of four treatments: control, basal diet; treatment 1, basal diet + 0.025% SP; treatment 2, basal diet + 0.050% SP; and treatment 3, basal diet + 0.100% SP. Growing pigs fed 0.050% SP diet had greater (P < 0.05) body weight and fecal Lactobacillus counts compared with pigs fed basal diet. Average daily gain and gain to feed ratio were greater (P < 0.05) in pigs fed 0.050% and 0.100% SP diets as compared with pigs fed basal diet. The apparent total tract digestibility (ATTD) of dry matter (DM) and superoxide dismutase (SOD) activity for pigs fed 0.050% SP diet tended to increase compared with pigs fed basal diet (P < 0.10). Pigs fed 0.025%, 0.050%, and 0.100% SP had a higher (P < 0.05) glutathione peroxidase (GPx) activity than pigs fed basal diet. In conclusion, SP supplementation improved growth performance and ATTD of DM, increased the SOD and GPx activity, and enhanced the fecal Lactobacillus counts in growing pigs.

Dissect the mode of action of probiotics in affecting host-microbial interactions and immunity in food producing animals

Prophylactic antimicrobials have been widely used in food animal production with the aim to prevent infectious diseases, enhance feed efficiency, and promote growth. However, the extensive use of antimicrobials in food animal production systems has led to the emergence of antimicrobial resistant pathogens, which are potential threats to human and animal health. Probiotics have been proposed to be a promising alternative of prophylactic antimicrobials, with potential beneficial effects on the host animal by improving the balance of intestinal microbiota and host immunity. Although an increasing body of evidence shows that probiotics could directly or indirectly affect gut microbiota and host immune functions, the lack of the understanding of how probiotics influence host-microbial interaction and immunity is one of the reasons for controversial findings from many animal trials, especially in food production animals. Therefore, in this review we focused on the most recent (last ten years) studies on how gut microbiota and host immune function changes in response to probiotics in food production animals (swine, poultry, and ruminant). In addition, the relationship between microbial changes and host immune function was illustrated, and how such relationship differs among animal species was further compared. Moreover, the future directions concerning the mechanisms of how probiotics modulate host-microbial interactions and host immunity were highlighted, which may assist in the optimal supplementation strategy to maximize the efficacy of probiotics to improve animal gut health and productivity.

Efficacy and safety assessment of microbiological feed additive for chicken broilers in tolerance studies

Introduction

One aim of the study was to evaluate the impact when added to feed of the two potentially probiotic strains of lactic acid bacteria (LAB) Lactobacillus plantarum K KKP 593/p and Lactobacillus rhamnosus KKP 825 on production performance, health, and the composition of gut microbiota. The complementary aim was to assess the safety of these strains in broiler rearing.

Material and Methods

A total of 500 one-day-old Ross 308 chicks were divided into four groups. The experimental factor was the admixture of bacterial preparation to the feed at different doses: the recommended maximum dose, a dose ten times higher, the recommended minimum dose, and a zero dose for the control group not receiving bacteria.

Results

Addition of bacteria to the diets did not have a significant effect on the final body weight, final body weight gain, nor total feed intake or feed conversion. However, lactic acid bacteria had a positive effect on chicken health. Mortality among chickens fed with LAB was reduced. Moreover, LAB feeding inhibited the growth of Salmonella spp. and Clostridium perfringens in the intestines. There were no significant differences in chicken performance by dose of bacteria in the feed. The group dosed with LAB ten times higher than the recommended maximum did not demonstrate changes in biochemical or haematological parameters of blood compared to the remaining groups.

Conclusion

Feeding chicken broilers with two potentially probiotic LAB strains is safe and impacts animal health positively.

Efficacy and Safety Assessment of Microbiological Feed Additive for Chicken Broilers in Tolerance Studies

INTRODUCTION

One aim of the study was to evaluate the impact when added to feed of the two potentially probiotic strains of lactic acid bacteria (LAB) Lactobacillus plantarum K KKP 593/p and Lactobacillus rhamnosus KKP 825 on production performance, health, and the composition of gut microbiota. The complementary aim was to assess the safety of these strains in broiler rearing.

MATERIAL AND METHODS

A total of 500 one-day-old Ross 308 chicks were divided into four groups. The experimental factor was the admixture of bacterial preparation to the feed at different doses: the recommended maximum dose, a dose ten times higher, the recommended minimum dose, and a zero dose for the control group not receiving bacteria.

RESULTS

Addition of bacteria to the diets did not have a significant effect on the final body weight, final body weight gain, nor total feed intake or feed conversion. However, lactic acid bacteria had a positive effect on chicken health. Mortality among chickens fed with LAB was reduced. Moreover, LAB feeding inhibited the growth of Salmonella spp. and Clostridium perfringens in the intestines. There were no significant differences in chicken performance by dose of bacteria in the feed. The group dosed with LAB ten times higher than the recommended maximum did not demonstrate changes in biochemical or haematological parameters of blood compared to the remaining groups.

CONCLUSION

Feeding chicken broilers with two potentially probiotic LAB strains is safe and impacts animal health positively.