Effects of dietary Lactobacillus plantarum B1 on growth performance, intestinal microbiota, and short chain fatty acid profiles in broiler chickens

Effect of supplementation with Glycyrrhiza uralensis extract and Lactobacillus acidophilus on growth performance and intestinal health in broiler chickens

Intestinal microbiota community is an important factor affecting the nutritional and health status of poultry, and its balance is crucial for improving the overall health of poultry. The study aimed to investigate the effect of dietary supplementation with Glycyrrhiza uralensis extract (GUE), Lactobacillus acidophilus (Lac) and their combination (GL) on growth performance and intestinal health in broilers in an 84-day feeding experiment. Supplementary 0.1% GUE and 4.5×107 CFU/g Lac significantly increased average daily gain (ADG), and GL (0.1% GUE and 4.5×107 CFU/g Lac) increased ADG and average daily feed intake (ADFI), and decreased feed conversion rate (FCR) in broilers aged 29 to 84 d and 1 to 84 d. Dietary GUE, Lac and GL increased the superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activity and decreased Malondialdehyde (MDA) content in the jejunum mucosa of broilers, and increased secretory IgA (sIgA) content in broilers at 84 d. Moreover, GUE, Lac and GL increased cecal microbial richness and diversity, and modulated microbial community composition. Both GUE and Lac reduced the harmful bacteria Epsilonbacteraeota, Helicobacter, and H. pullorum at 28 d and Proteobacteria, Escherichia, and E. coli at 84 d, while Lac and GL increased beneficial bacteria Lactobacillus and L. gallinarum at 28 d. Compared with individual supplementation, GL markedly increased the SOD activity and the sIgA content, and reduced Helicobacter and Helicobacter pullorum. In conclusion, GUE and Lactobacillus acidophilus as feed additives benefit growth performance and intestinal health, and their combined use shows an even more positive effect in broilers.

Combined Effect of Nigella sativa and Kefir on the Live Performance and Health of Broiler Chickens Affected by Necrotic Enteritis

Coccidiosis and necrotic enteritis (NE) are prevalent poultry ailments worldwide, leading to decreased live performance and elevated mortality rates without antibiotic usage. This study evaluated Nigella sativa (black cumin) seeds (BCS) and kefir as alternatives to antibiotics for broilers. An in vivo study over a 28-day period, using 384 Cobb 500 male broilers organized into six treatment groups as part of a completely randomized block experimental design was conducted. Each treatment group included eight replicates, with each replicate containing eight birds. The treatments included positive control, negative control, antibiotic control, 5% BCS in feed, 20% kefir in drinking water, and a combination of 5% BCS and 20% kefir. NE was induced in broilers by administering ~5000 oocysts of Eimeria maxima orally on day 14, followed by inoculation with about 108 CFU/mL of Clostridium perfringens (Cp) (strain Cp#4) on days 19, 20, and 21. Live performance metrics including feed intake, body weight gain, and feed conversion were assessed in broilers. Additionally, NE disease outcomes such as lesion scores, mortality rates, and Cp populations in cecum were determined during the study. The BCS, kefir, and the combination had no detrimental effect on broiler live performance. BCS-treated and combination groups had lower NE scores (p > 0.05) in comparison to the positive control and exhibited no significant difference (p > 0.05) from antibiotic control. Additionally, treatment groups and antibiotic control were not significantly different (p > 0.05) in mortality, whereas the BCS and kefir combination significantly reduced (p < 0.05) mortality to 14.1% compared to 31.3% for the positive control. C. perfringens vegetative cells significantly decreased (p < 0.05) in treatments with BCS, kefir, and their combination on days 22 and 28 compared to the positive control. On day 22, Cp sores were significantly lower (p < 0.05) for the kefir and combination treatments compared to the positive control. In conclusion, BCS and kefir successfully reduced C. perfringens infection and mortality without any detrimental impact on broiler live performance with the combined treatment being the most effective. These results suggest that BCS and kefir could serve as potential alternatives to antibiotics in managing NE.

Dietary Supplementation of Compound Probiotics Improves Intestinal Health by Modulated Microbiota and Its SCFA Products as Alternatives to In-Feed Antibiotics

Enterococcus faecium, Bifidobacterium, and Pediococcus acidilactici, as intestinal probiotics, have been proved to play a positive role in treating intestinal diseases, promoting growth and immune regulation in poultry. The aim of this study was to evaluate the effect of compound probiotics on growth performance, digestive enzyme activity, intestinal microbiome characteristics, as well as intestinal morphology in broiler chickens. Treatment diets with chlortetracycline and compound probiotics were used for two groups of sixty broilers each throughout the feeding process. Another group was fed the basal diet. The BW (2589.41 ± 13.10 g vs 2422.50 ± 19.08 g) and ADG (60.57 ± 0.31 g vs 56.60 ± 0.45 g) of the compound probiotics added feed treatment group were significantly increased, and the FCR was significantly decreased (P < 0.05). The supplementation of a compound probiotics enhanced the abundance of beneficial bacteria such as Lactobacillus, Faecalibacterium, and norank_f_norank_o_Clostridia_vadinBB60_group (P < 0.05), and modulated the cecal microbiota structure, thereby promoting the production of short-chain fatty acids (SCFAs) and elevating their levels (P < 0.05), particularly propionic and butyric acids. Furthermore, the administration of the compound probiotics supplements significantly enhanced the villi height, V/C ratio, and reduced the crypt depth (P < 0.05). In addition, the activity of digestive enzymes in the duodenum and jejunum was elevated (P < 0.05). Collectively, the selected compound probiotics supplemented in this experiment have demonstrated efficacy, warranting further application in practical production settings as a viable alternative to antibiotics, thereby facilitating efficient production and promoting gastrointestinal health.

Physical and Chemical Characteristics of Droppings as Sensitive Markers of Chicken Health Status

The aim of this study was to analyze the physical and chemical characteristics of chicken droppings (n = 73), which were collected during different age periods and classified by visual inspection into normal (N) and abnormal (A). Significant differences were found in the texture, pH, dry matter (DM), fatty acids (FAs), short-chain fatty acids (SCFAs), and volatile compounds (VCs) between the tested dropping groups (p ≤ 0.05). The age period of the chicken had a significant influence on the color coordinates, texture, pH, DM, and SCFA contents in N and A as well as on all FAs content in N (p ≤ 0.05). Droppings from the N group had a harder texture, lower values of a* and b* color coordinates, higher DM content, higher level of linoleic FA, and lower level of α-linolenic FA than the droppings from the A group in each age period (p ≤ 0.05). The predominant SCFA was acetic acid, the content of which was significantly lower in the N group compared to that of the A group. The alcohol and organic acid contents were the highest in most of the A group at different age periods, while ketones dominated in the N and A groups. In conclusion, the majority of the tested dropping characteristics were influenced by the age period. While certain characteristics demonstrate differences between N and A, a likely broader range of droppings is required to provide more distinct trends regarding the distribution of characteristics across different droppings.

Systematic review on microbiome-related nutritional interventions interfering with the colonization of foodborne pathogens in broiler gut to prevent contamination of poultry meat

This systematic review aimed to compile the available body of knowledge about microbiome-related nutritional interventions contributing to improve the chicken health and having an impact on the reduction of colonization by foodborne pathogens in the gut. Original research articles published between 2012 and 2022 were systematically searched in Scopus and PubMed. A total of 1,948 articles were retrieved and 140 fulfilled the inclusion criteria. Overall, 73 papers described 99 interventions against colonization by Escherichia coli and related organisms; 10 papers described 15 interventions against Campylobacter spp.; 36 papers described 54 interventions against Salmonella; 40 papers described 54 interventions against Clostridium perfringens. A total of 197 microbiome-related interventions were identified as effective against one or more of the listed pathogens and included probiotics (n = 80), prebiotics (n = 23), phytobiotics (n = 25), synbiotics (n = 12), organic acids (n = 12), enzymes (n = 4), essential oils (n = 14) and combination of these (n = 27). The identified interventions were mostly administered in the feed (173/197) or through oral gavage (11/197), in the drinking water (7/197), in ovo (2/197), intra amniotic (2/197), in fresh or reused litter (1/197) or both in the feed and water (1/197). The interventions enhanced the beneficial microbial communities in the broiler gut as Lactic acid bacteria, mostly Lactobacillus spp., or modulated multiple microbial populations. The mechanisms promoting the fighting against colonization by foodborne pathogens included competitive exclusion, production of short chain fatty acids, decrease of gut pH, restoration of the microbiome after dysbiosis events, promotion of a more stable microbial ecology, expression of genes improving the integrity of intestinal mucosa, enhancing of mucin production and improvement of host immune response. All the studies extracted from the literature described in vivo trials but performed on a limited number of animals under experimental settings. Moreover, they detailed the effect of the intervention on the chicken gut without details on further impact on poultry meat safety.

Impact of fermented feed of soybean hulls and rapeseed cake on immunity, antioxidant capacity, and gut microbiota in Chahua chicken

The present study investigated the effects of replacing part of the basal diet with 2-stage fermented feed (FF) (soybean hulls:rapeseed cake (2:1, m/m)) on the growth performance, immunity, antioxidant capacity, and intestinal health of Chahua chicken. A total of 160 Chahua chickens were randomly divided into 4 groups to receive a control diet or diet with 5%, 10%, or 15% of the basal diet replaced by FF, respectively for 56 d. The results showed that FF significantly improved the average daily gain (ADG) and average daily feed intake (ADFI) of Chahua chickens (P < 0.05). Furthermore, the serum immunoglobulin (Ig) A, glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) in Chahua chicken receiving the diet added with 15% FF significantly increased (P < 0.05). Chahua chicken in both the 10% and 15% groups showed increased serum IgG and IgM and decreased malondialdehyde. Serum interleukin-2 and interferon-gamma significantly increased in all FF groups. Compared with the CON group, higher ileal villus height (VH) was found in the 10% FF group. Treatment with FF significantly increased the ileal villus height/crypt depth (VH/CD) ratio, jejunal VH, and jejunal VH/CD ratio while reducing ileal and jejunal CD. The modified gut microbiota composition was observed in the Chahua chicken fed a diet containing FF, in particular, with the increased abundance of Faecalibacterium and Lactobacillus. The abundance of Lactobacillus significantly increased in the 10% and 15% FF groups (all P < 0.05). Correlation analysis revealed a positive correlation between Lactobacillus and VH (R = 0.38, P = 0.10, Figure 3B), AH/CD ratio (R = 0.63, P = 0.003), and a negative correlation with CD (R = -0.72, P = 0.001). These results indicate that FF improves immunity, antioxidant capacity, and intestinal health and consequently enhances growth performance in Chahua chicken.

Effects of Probiotic Lactiplantibacillus plantarum HJLP-1 on Growth Performance, Selected Antioxidant Capacity, Immune Function Indices in the Serum, and Cecal Microbiota in Broiler Chicken

This research study aimed to investigate the effects of Lactiplantibacillus plantarum (L. plantarum) on growth performance, oxidation resistance, immunity, and cecal microbiota in broilers. This work classed three hundred and sixty 1-day-old male broilers into three groups randomly, including a control group (CON, basal diet) and antibiotic (ANT, 75 mg kg-1 chlortetracycline added into basal diet) and probiotic groups (LP, 5 × 108 CFU kg-1Lactiplantibacillus plantarum HJLP-1 contained within basal diet). Animals were then fed for 42 days, and each group comprised eight replicates with 15 broilers. Compared with CON, L. plantarum supplementation significantly improved the average daily weight gain (AWDG) (p < 0.05) while reducing the feed-gain ratio over the entire supplemental period (p < 0.05). Birds fed L. plantarum had markedly lower serum ammonia and xanthine oxidase levels (p < 0.05) than those in the ANT and CON groups. Significant improvements (p < 0.05) in superoxide dismutase, catalase, and serum IgM and IgY contents in broilers fed L. plantarum were also observed when compared with those in the CON and ANT groups. Both L. plantarum and antibiotics decreased pro-inflammatory factor IL-1β levels significantly (p < 0.05), while only L. plantarum promoted anti-inflammatory factor IL-10 levels in the serum (p < 0.05) compared with CON. L. plantarum (p < 0.05) increased acetic acid and butyric acid concentrations in cecal contents when compared to those in CON and ANT. Among the differences revealed via 16S rRNA analysis, L. plantarum markedly improved the community richness of the cecal microbiota. At the genus level, the butyric acid-producing bacteria Ruminococcus and Lachnospiraceae were found in higher relative abundance in samples of L. plantarum-treated birds. In conclusion, dietary L. plantarum supplementation promoted the growth and health of broilers, likely by inducing a shift in broiler gut microbiota toward short-chain fatty acid (SCFA)-producing bacteria. Therefore, L. plantarum has potential as an alternative to antibiotics in poultry breeding.

Effects of Lactobacillus plantarum HW1 on Growth Performance, Intestinal Immune Response, Barrier Function, and Cecal Microflora of Broilers with Necrotic Enteritis

The purpose of the study was to investigate the effects of Lactobacillus plantarum HW1 on growth performance, intestinal immune response, barrier function, and cecal microflora of broilers with necrotic enteritis. In total, 180 one-day-old male Cobb 500 broilers were randomly allocated into three groups comprising a non-infected control (NC) group, basal diet + necrotic enteritis challenge (NE) group, and basal diet + 4 × 106 CFU/g Lactobacillus plantarum HW1 + necrotic enteritis challenge (HW1) group. Broilers in the NE and HW1 groups were orally given sporulated coccidian oocysts at day 14 and Clostridium perfringens from days 19 to 21. The results showed that the HW1 treatment increased (p < 0.05) the average daily gain of broilers from days 15 to 28 and from days 0 to 28 compared with the NE group. Moreover, the HW1 treatment decreased (p < 0.05) the oocysts per gram of excreta, intestinal lesion scores, ileal interleukin (IL) 1β and tumor necrosis factor α levels, and serum D-lactic acid and diamine oxidase levels, while increasing (p < 0.05) the ileal IL-10 level, thymus index, and protein expressions of ileal occludin and ZO-1. Additionally, the HW1 treatment decreased (p < 0.05) the jejunal and ileal villus height, jejunal villus height/crypt depth value, and cecal harmful bacterial counts (Clostridium perfringens, Salmonella, Escherichia coli, and Staphylococcus aureus), and increased (p < 0.05) the cecal Lactobacillus count. In conclusion, dietary supplementation with 4 × 106 CFU/g Lactobacillus plantarum HW1 could relieve necrotic enteritis infection-induced intestinal injury and improve growth performance in broilers by improving intestinal barrier function and regulating intestinal microbiology.

The Prophylactic Protection of Salmonella Typhimurium Infection by Lentilactobacillus buchneri GX0328-6 in Mice

Salmonellosis is a disease caused by non-typhoid Salmonella, and although some lactic acid bacteria strains have been shown previously to relieve Salmonellosis symptoms, little has been studied about the preventive mechanism of Lentilactobacillus buchneri (L. buchneri) against Salmonella infection in vivo. Therefore, the L. buchneri was fed to C57BL/6 mice for 10 days to build a protective system of mice to study its prevention and possible mechanisms. The results showed that L. buchneri GX0328-6 alleviated symptoms caused by Salmonella typhimurium infection among C57BL/6 mice, including low survival rate, weight loss, increase in immune organ index and hepatosplenomegaly, and modulated serum immunoglobulin levels and intrinsic immunity. Importantly, the L. buchneri GX0328-6 enhanced the mucosal barrier of the mouse jejunum by upregulating the expression of tight junction proteins such as ZO-1, occludins, and claudins-4 and improved absorptive capacity by increasing the length of mouse jejunal villus and the ratio of villus length to crypt depth and decreasing the crypt depth. L. buchneri GX0328-6 reduced the intestinal proliferation and invasion of Salmonella typhimurium by modulating the expression of antimicrobial peptides in the intestinal tract of mice, and reduced intestinal inflammation and systemic spread in mice by downregulating the expression of IL-6 and promoting the expression of IL-10. Furthermore, L. buchneri GX0328-6 increased the relative abundance of beneficial bacteria colonies and decreased the relative abundance of harmful bacteria in the cecum microflora by modulating the microflora in the cecum contents.

Significance of Limosilactobacillus fermentum and Saccharomyces cerevisiae on the Growth Performance, Haematological Traits, Serum Biochemistry, Faecal and Caeca Microbiota of Broiler Chickens

OBJECTIVE

The aim of the study was to supplement Lactobacillus and yeast in broiler feed by replacing immunomodulators to develop antibiotic free meat and egg production by analyzing broiler performance, haematological traits, serum biochemistry, histopathology, fecal bacterial count, and metagenomic analysis of broiler ceca.

METHOD

Two cultures i.e. KGL4 (Limosilactobacillus fermentum MTCC 25515) and WBS2A (Saccharomyces cerevisiae GI: MG101828) were considered for the evaluation of Broiler chicken's health and growth during 42 days study without supplementing immunomodulators and commercial probiotics in poultry feeds. The 96-day-old broiler chickens were grouped into: T1 [Control: basal diet + immunomodulatory factor and commercial probiotic], T2 [Basal diet without immunomodulatory factor and commercial probiotic + KGL4 (108 CFU/mL), T3 [Basal diet without immunomodulatory factor and commercial probiotic + WBS2A (107 CFU/mL), and T4 [Basal diet without immunomodulatory factor and commercial probiotic + KGL4 + WBS2A in a 1:1 ratio] (Institutional Animal Ethics Committee (IAEC) No. 365/PRS/2022). The following parameters, i.e., body weight gain, feed consumption ratio (FCR), white blood cell count (WBC), red blood cell count (RBC), hemoglobin content, platelet count, cholesterol content, triglycerides, high density lipoprotein (HDL), very low-density lipoprotein (VLDL), fecal counts and metagenomic analysis of broiler ceca samples, were measured.

RESULTS

In the study, amongst various traits, the overall performance of the group treated along with Limosilactobacillus fermentum (KGL4) showed improved results as compared to control group. Limosilactobacillus fermentum (KGL4) treated group had higher body weight gain (2583.04 ± 35.421 g), FCR (1.60 ± 0.019), WBC (235.60 ± 2.562 × 103/µL), hemoglobin content (14.10 ± 0.442 g/dl), and HDL (131.40 ± 11.400 mg/dl). The investigation did not show significant variations in the relative proportions of genus or phylum among various groups during metagenomic analysis of ceca samples. There was also an improvement in haematological traits; no evidence of necrosis in heart, intestine and liver tissues.

CONCLUSIONS

The present study conclude that it is safe to feed Limosilactobacillus fermentum and Saccharomyces cerevisiae to broilers as feed supplements and also supports the current knowledge regarding the use of yeast and lactic acid bacteria as an effective alternative stimulant for maintaining health and growth of broiler chickens.

Lactobacillus plantarum GX17 benefits growth performance and improves functions of intestinal barrier/intestinal flora among yellow-feathered broilers

Lactobacillus plantarum has recently been found to be a natural source feed additive bacteria with great advantages in food safety and animal welfare. Discovering novel strains with commercial application potentiation could benefit the local poultry industry, and in particular support Chinese farmers. In this study, we tested a recently isolated novel strain of Lactobacillus plantarum GX17 as a feed additive on the growth performance and intestinal barrier functions of 1-day-old Chinese yellow-feather chicks. As good as other commercial probiotics, feeding with Lactobacillus plantarum GX17 showed significant improvements in humoral immune responses and enhanced the immune effect after vaccination for either the Newcastle disease vaccine or the avian influenza vaccine. This study also found that feeding with Lactobacillus plantarum GX17 improved the feed-to-weight ratio and caused a significant increase of the villus length to crypt depth ratio. Furthermore, Lactobacillus plantarum GX17 significantly up-regulated the mRNA expression of CLDN, MUC2, and TLR2, all of which are jejunum-associated barrier genes, indicating an improvement of the intestinal barrier functions by enhancing the tight junction between epithelia cells. These results are comparable to the effects of feeding the commercial complex probiotics that improve the expression levels of CLDN, ocludin, MUC2, TLR2, and TLR4. In terms of maintaining intestinal health, commercial complex probiotics increased the relative abundance of Parabacteroides and Romboutsia, while Lactobacillus plantarum GX17 increased the relative abundance of Pseudoflavonifractor. Our data suggest that Lactobacillus plantarum GX17 could enhance the intestinal absorption of nutrients and therefore improve the growth performance of Chinese yellow-feather chicks. In conclusion, compared with the commercial complex probiotics, Lactobacillus plantarum GX17 has more positive effects on the growth performance and intestinal barrier function of yellow-feather chickens, and can be used as a feed additive.

Characterization of potential probiotics Lactobacillus species isolated from the gastrointestinal tract of Rhode Island Red (RIR) chicken in Ethiopia

Background and aims

Nowadays, probiotic microorganisms are given high attention due to their potential for the improvement of animal production and productivity. The natural gut microflora of poultry can serve as an excellent source of optimum probiotic strains. Therefore, this study isolated, identified and characterized potential probiotic Lactobacillus strains from the digestive tract content of RIR chicken in Ethiopia.

Methods

A total of five RIR chickens were randomly taken and a sample was taken from each gastrointestinal content for further analysis. For further characterization, among 190 isolates only 10 representative isolates were randomly taken for further in vitro probiotic potential characterization. The selected isolates were screened and identified based on the biochemical, morphological, and 16S rRNA gene sequences.

Results

Survival isolates of IS3, IS4, IS6, and IS7 were significantly different (P < 0.05) at pH 2. IS3, IS4, IS6, and IS7 showed tolerance for 0.3% bile salt. Isolates of IS1, IS2, IS5, IS7, and IS8 were ampicillin-resistant, and chloramphenicol, ciprofloxacin, and erythromycin were used as antibiotics. All ten isolates showed antagonistic activity against Escherichia coli, Staphylococcus aureus, Salmonella typhimurium, Staphylococcus intermedius, and Salmonella enteritidis. The optimum temperature for all isolates was 45 °C, and all the isolates could grow at 0.69 mol/L of NaCl. Using phylogenetic analysis of the 16SrRNA gene sequence; IS3 was identified as Lactobacillus salivarius, while IS4, IS6, and IS7 were identified as Lactobacillus reuteri.

Conclusions

The results indicated that the selected Lactobacillus isolates can survive the stress conditions of the gastrointestinal tract and can thus be considered potential probiotic candidates for chickens.

Bacillus subtilis PM5 from Camel Milk Boosts Chicken Immunity and Abrogates Salmonella entertitidis Infections

With the practice of a successful livestock industry using antibiotics, which has continued for more than five decades, researchers have long been interested in finding alternatives to antibiotics for poultry production. Probiotics can potentially reduce enteric diseases in livestock and enhance their productivity. The aim of this study was to isolate putative probiotics from camel milk and test them against Salmonella infection as well as host immune development. Thirteen different isolates were obtained from six different camel milk samples from dairy farms in Saudi Arabia. Three of the six isolates (PM1, PM2, PM3, PM4, PM5, and PM6) that showed Gram-positive characters reacted negatively to catalase and hemolytic assays. PM1, PM5, and PM6 showed significant nonpolar surface properties (>51% hydrophobic) and potent antimicrobial activities against avian pathogens, namely S. enterica, S. typhi, S. aureus, and E. coli. PM5 exhibited substantial probiotic traits; therefore, further focus was given to it. PM5 was identified as Bacillus subtilis OQ913924 by the 16S rRNA sequencing method and showed similarity matrix > 99%. An in vivo chicken model was used to access the health benefits of probiotics. After salmonella infection, the mucosal immune response was significantly increased (p < 0.01), and none of the challenge protocols caused mortality or clinical symptoms after infection in intestinal contents. S. enterica organ infiltration in the spleen, thymus, and small intestine was significantly reduced in the B. subtilis PM5-fed chickens. The S. enterica load in chicken feces was reduced from CFU 7.2 to 5.2 in oral-fed B. subtilis PM5-fed chickens. Probiotic-fed chickens showed buffered intestinal content and positively regulated the level of butyric acid (p < 0.05), and intestinal interleukin 1 beta (IL1-β), C-reactive protein (CRP), and interferon gamma (IFN-γ) levels were reduced (p < 0.05). In addition, B. subtilis PM5 showed significant binding to peritoneal macrophages cells and inhibited S. enterica surface adhesion, indicating co-aggregation of B. subtilis PM5 in macrophage cells. It could be concluded that supplementation with probiotics can improve the growth performance of broilers and the quality of broiler chickens against enteric pathogens. The introduction of this probiotic into the commercial poultry feed market in the near future may assist in narrowing the gap that now exists between chicken breeding and consumer demand.

Effect of Oral Administration with Lactobacillus plantarum CAM6 on the Hematological Profile, Relative Weight of Digestive Organs, and Cecal Traits in Growing Pigs

This study aimed to investigate the effects of oral administration with L. plantarum CAM6 on the hematological profile, relative weight of digestive organs, and cecal traits in growing pigs. A total of 36 castrated male pigs [(Landrace × Pietrain) × Duroc] aged 49 to 139 days old were randomly assigned to 3 experimental groups with 12 animals per treatment. The treatments included a control diet without additives (CTRL), a positive control with subtherapeutic antibiotics (TRT1), and CTRL supplemented with 5 mL Lactobacillus plantarum CAM6 preparation providing 10⁹ CFU/pig/day (TRT2). The TRT2 group showed a higher (p ≤ 0.05) small intestine length and the cecum relative weight compared to the CTRL group. Moreover, L. plantarum CAM6 supplementation promoted (p ≤ 0.05) increased thickness of the muscular and mucosal layers, as well as enhanced depth and width of the cecal crypts. The TRT2 group also showed well-defined crypts without lesions, while the CTRL and TRT1 groups exhibited congestion, lymphocytic infiltration in the crypt, and intestinal-associated lymphoid tissue atrophy, respectively. Additionally, TRT2 stimulated (p ≤ 0.05) the growth of the autochthonous cecal microbiota compared to other experimental groups. Overall, the results indicate that oral administration of L. plantarum CAM6 improved intestinal health and enhanced the growth of autochthonous cecal lactic acid bacteria and had no impact on the complete blood count in growing pigs.

Probiotics and vitamins modulate the cecal microbiota of laying hens submitted to induced molting

Induced molting enables laying hens to relax, restore energy and prolong the laying hen cycle, resolving problems such as poor egg quality and minimizing economic losses caused by rising global feeding costs. However, traditional molting methods may disrupt gut microflora and promote potential pathogens infections. This study used a customized additive with a mixture of probiotics and vitamins to induce molting and examine the cecal microbiota post molting. A total of two hundred 377 day-of-ISA Brown laying hens were randomly assigned to four groups: non-molt with basal diet (C), 12-day feeding restriction (FR) in earlier-molting (B), feed again to 27.12% egg production in middle-molting (A) and reach second peak of egg production over 81.36% in post-molting (D). Sequencing 16S rRNA to analyze cecal microbial composition revealed that there is no significant change in bacterial community abundance post-molting. In contrast to group C, the number of potentially harmful bacteria such as E. coli and Enterococcus was not found to increase in groups B, A, or D. This additive keeps cecal microbiota diversity and community richness steady. In cecal contents, hens in group B had lower Lactobacillus, Lachnospiraceae and Prevotellaceae (vsC, A, and D), no significant differences were found between post-molting and the non-molting. Furthermore, cecal microbiota and other chemicals (antibodies, hormones, and enzymes, etc.) strongly affect immunological function and health. Most biochemical indicators are significantly positively correlated with Prevotellaceae, Ruminococcaceae and Subdoligranulum, while negatively with Phascolarctobacterium and Desulfovibrio. In conclusion, the additive of probiotics and vitamins improved the cecal microbiota composition, no increase in the associated pathogenic microbial community due to traditional molting methods, and enhances hepatic lipid metabolism and adaptive immunological function, supporting their application and induced molting technology in the poultry breeding industry.

Effect of Dietary Supplementation of Lactiplantibacillus plantarum N-1 and Its Synergies with Oligomeric Isomaltose on the Growth Performance and Meat Quality in Hu Sheep

Probiotics have gained tremendous attention as an alternative to antibiotics, while synbiotics may exhibit a greater growth promoting effect than their counterpart probiotics due to the prebiotics' promotion on the growth and reproduction of probiotics. The objective of this study was to investigate the influence of Lactiplantibacillus plantarum N-1 and its synbiotic with oligomeric isomaltose on the growth performance and meat quality of Hu sheep. Hu sheep (0-3 days old) were fed with water, probiotics of N-1, or synbiotics (N-1 and oligomeric isomaltose) daily in three pens for 60 days and regularly evaluated to measure growth performance and collect serum (five lambs per group). Longissimus thoracis (LT) and biceps brachii (BB) muscle tissues were collected for the analysis of pH value, color, texture, nutrients, mineral elements, amino acids, volatile compounds, and antioxidant capacity. The results showed that dietary supplementation of N-1 tended to improve growth performance and meat quality of Hu sheep, while the synergism of N-1 with oligomeric isomaltose significantly improved their growth performance and meat quality (p < 0.05). Both the dietary supplementation of N-1 and synbiotics (p < 0.05) increased the body weight and body size of Hu sheep. Synbiotic treatment reduced serum cholesterol and improved LT fat content by increasing the transcription level of fatty acid synthase to enhance fat deposition in LT, as determined via RT-qPCR analysis. Moreover, synbiotics increased zinc content and improved LT tenderness by decreasing shear force and significantly increased the levels of certain essential (Thr, Phe, and Met) and non-essential (Asp, Ser, and Tyr) amino acids of LT (p < 0.05). Additionally, synbiotics inhibited the production of carbonyl groups and TBARS in LT and thus maintained antioxidant stability. In conclusion, it is recommended that the use of synbiotics in livestock breeding be promoted to improve sheep production and meat quality.

Integrative analysis of transcriptome and metabolome reveals probiotic effects on cecal metabolism in broilers

BACKGROUND

Probiotics play an important role in the host and have attracted widespread attention as an alternative to antibiotics. Arbor Acres broilers were used in the present experiment and fed different doses of compound probiotics at 1, 5, and 10 g kg^-1 . The effects of compound probiotics on broiler growth performance and cecal transcriptome and metabolome were investigated.

RESULTS

We discovered 425 differentially expressed genes (DEGs; upregulated: 256; downregulated: 169) in the cecal transcriptome study. These DEGs were assigned to fat metabolic pathways, such as the peroxisome proliferator-activated receptor (PPAR) signaling pathway, according to KEGG analysis. Probiotics downregulated LPL and upregulated PPARα expression in the cecum. In metabolome analysis of the cecum of cecum, we screened 86 differential metabolites and performed KEGG enrichment analysis of these metabolites. The KEGG analysis showed that these differentially expressed metabolites were annotated to nucleotide metabolism-related pathways, such as purine metabolism. In the cecum, probiotics upregulated the content of guanine, AMP, 3'-AMP, adenylosuccinate, deoxyguanosine, and ADP-ribose, whereas they downregulated the content of 5-hydroxyisourate. Comprehensive transcriptome and metabolome analysis revealed that glycolysis, gluconeogenesis, and glycerophospholipid metabolism pathways were jointly enriched in cecum of broilers fed a probiotic-containing diet.

CONCLUSION

This study provides valuable information for studying the regulation and gene metabolism network of probiotics on cecal metabolism in broilers. © 2022 Society of Chemical Industry.

Exogenous protease supplementation to the diet enhances growth performance, improves nitrogen utilization, and reduces stress in finishing pigs

We have conducted this experiment to evaluate a new exogenous protease in finishing pigs' growth performance, nutrient digestibility, gas emission, blood profiles, and meat quality. A total of 200 pigs of 52.15 ± 2.31 kg average body weight (BW) were divided into four dietary treatments named as: CON, basal diet; TRT1, basal diet + 0.05% protease; TRT2, basal diet + 0.1% protease; TRT3, basal diet + 1.5% protease. Each treatment consisted of 10 pens, where five pigs were allotted to each pen according to their body weight and sex. The dietary treatments were allotted to the pens in a randomized block design. During this 10-week-long experiment, BW, average daily gain (ADG), average daily feed intake (ADFI), and gain to feed ratio (G:F) were calculated for Week 0-5, Week 6-10, and the overall period. During Week 6-10, ADG was higher in TRT2 and TRT3 than in the CON and TRT1 groups. At the same time, a linear increase was observed in ADG and G:F of the pigs. In addition, the final BW of pigs' was linearly increased by protease supplementation. On Week 10, there was a linear trend of increase (p = 0.0575) in crude protein digestibility and a trend of linear reduction (p = 0.0651) in NH₃ gas emission. In blood profile, cortisol presented a linear decrease in both Week 5 (p = 0.251) and Week 10 (p = 0.0585). In addition, increasing doses of protease showed a trend of linear increase (p = 0.0592) in creatinine, whereas linear reduction was observed in the concentration of epinephrine (p = 0.0636) and norepinephrine (p = 0.0167) during Week 10. In conclusion, protease supplementation helped in improving daily gain in finishing pigs through protein digestibility with associated reduction of ammonia emission and blood stress hormones.

Effects of Lactobacillus plantarum and its Fermentation Products on Growth Performance, Immune Function, Intestinal pH and Cecal Microorganisms of Lingnan Yellow Chicken

The present research was conducted to investigate the effects of dietary supplementation of Lactobacillus plantarum and its fermentation products on growth performance, specific immune function, intestinal pH, and cecal microorganisms in yellow-feather broilers. A total of 1,200 yellow-feather broilers of similar weight and good health condition at 1 d of age were selected and randomly divided into 5 groups. The CK group was fed the basal diet, and the experimental group (I, II, III, IV) were supplemented with 0.1, 0.15% L. plantarum and 3, 4% L. plantarum fermentation products. The results showed that each treatment could improve the growth performance (P < 0.05) and feed conversion rate of yellow-feather broilers. Besides, the pH value of the gastrointestinal tract of yellow-feather broilers (P < 0.05) was significantly reduced through the use of L. plantarum and its fermentation products as additives, which also facilitated the animals to regulate the balance of cecal microorganisms. The immune function assay showed that the bursal index (P < 0.05), spleen index (P < 0.05), and the content of serum immunoglobulins IgA and IgG (P < 0.05) were significantly increased in yellow-finned broilers aged 1 to 21 d by supplementing the diet with L. plantarum. In conclusion, adding L. plantarum or its fermentation products to the diet can improve the growth performance of yellow-feather broilers, and the direct addition of L. plantarum is better than adding fermentation products.

Lactobacillus (L. plantarum & L. rhamnosus) and Saccharomyces (S. cerevisiae): effects on performance, biochemical parameters, ammonium ion in manure, and digestibility of broiler chickens

Two strains of Lactobacillus combined with Baker's yeast (Saccharomyces cerevisiae) used as probiotics were evaluated to replace antibiotics in poultry flocks by reducing ammonia emissions in manure of broilers without comprising performance or health. One-day-old Cobb 500 broilers (600) were fed starter, grower, and finisher diets as control (CON); probiotic S. cerevisiae, inclusion rate at 4.26 × 10⁶ CFU/kg of feed (SCY); probiotic L. plantarum and L. rhamnosus, inclusion rate at 4.35 × 10⁸ CFU/kg of feed (LPR) for each; and a combination of Lactobacillus plantarum and L. rhamnosus at 4.35 × 10⁸ CFU/kg of feed for each plus Saccharomyces cerevisiae and 4.26 × 10⁶ CFU/kg of feed (SWL). The 4 treatments had 5 replicates (pens), each with 30 broilers. Performance was measured weekly as feed consumption, weight gain, BW, and feed conversion ratio (FCR) over a 6-wk grow-out period. Accompanying biochemical analyses included lipase activity of the pancreas, liver weight, and uric acid (UA) concentration in liver. Albumin, total protein, UA, ammonia, and blood urea nitrogen (BUN) were measured in serum. Ammonium (NH₄⁺) in manure and apparent ileal digestibility from digesta were also measured. Significance was determined at P ≤ 0.05. Results showed that biochemical analyses had no significant treatment effect; however, there were significant temporal changes in performance measures for individual treatments. Feed consumption increased over time for all treatments (P = 2.00 × 10^-16). CON had lower weight gain in wk 2 (P = 0.013) compared to all treatment and the lowest BW in wk 5 (P = 0.0008) and wk 6 (P = 0.0124) compared to SWL. Specific probiotic strains, with well-defined inclusion rates, and surrounding environmental analyses of present microbes are needed to ascertain effects of probiotics. Other important areas for investigation include 1) confirmation of probiotics present in the digesta/ceca and how they alter the microbiota within the gastrointestinal (GI) tract and 2) the serum heterophil:lymphocyte ratio to further examine potential immune responses to the probiotics.

Antibiotics in avian care and husbandry-status and alternative antimicrobials

Undoubtedly, the discovery of antibiotics was one of the greatest milestones in the treatment of human and animal diseases. Due to their over-use mainly as antibiotic growth promoters (AGP) in livestock farming, antimicrobial resistance has been reported with increasing intensity, especially in the last decades. In order to reduce the scale of this phenomenon, initially in the Scandinavian countries and then throughout the entire European Union, a total ban on the use of AGP was introduced, moreover, a significant limitation in the use of these feed additives is now observed almost all over the world. The withdrawal of AGP from widespread use has prompted investigators to search for alternative strategies to maintain and stabilize the composition of the gut microbiota. These strategies include substances that are used in an attempt to stimulate the growth and activity of symbiotic bacteria living in the digestive tract of animals, as well as living microorganisms capable of colonizing the host’s gastrointestinal tract, which can positively affect the composition of the intestinal microbiota by exerting a number of pro-health effects, i.e., prebiotics and probiotics, respectively. In this review we also focused on plants/herbs derived products that are collectively known as phytobiotic.

Laying performance, egg quality, fertility, nutrient digestibility, digestive enzymes activity, gut microbiota, intestinal morphology, antioxidant capacity, mucosal immunity, and cytokine levels in meat-type Japanese quail breeders fed different phytogenic levels

A total of 180 female Japanese quail breeders were allocated to 5 treatments with 6 replicates of 6 birds and fed a diet supplemented with 0, 125, 250, 500, or 1000 mg/kg of a phytogenic feed additive (PFA) in a 9-wk experiment. Egg weight, feed efficiency, shell breaking strength and calcium content, specific gravity, Haugh unit, and percentages of fertile eggs increased with increasing PFA levels (P < 0.05). Increasing of PFA levels increased nutrient digestibility, dietary AMEn, and activities of digestive enzymes in the pancreas and intestinal digesta (P < 0.05). Supplementation of PFA reduced Escherichia coli (P < 0.05), Clostridium spp. (P < 0.05) and Salmonella spp. counts (P < 0.05), while increased Lactobacillus and Bifidobacterium spp. counts in the ileal and cecal contents (P < 0.05). Dietary PFA increased jejunal villus height and decreased ileal crypt depth (P < 0.05). Serum diamine oxidase activity and D-lactate level were decreased with increase in PFA level (P < 0.05). Increasing PFA levels increased glutathione peroxidase activity in the pancreas, small intestine, and cecal tonsil, but decreased malondialdehyde contents (P < 0.05). Birds fed PFA exhibited increased levels of secretory IgA in the intestinal mucosa (P < 0.05), and increased the percentage of CD3+ T cells, ratio of CD4+/CD8+ T cells, and cytokine concentrations in the cecal tonsils (P < 0.05). In conclusion, PFA could improve gut health and nutrient utilization and, therefore, benefit productivity, egg quality, and fertility in quails.

Sodium humate alters the intestinal microbiome, short-chain fatty acids, eggshell ultrastructure, and egg performance of old laying hens

This study investigated the effect of sodium humate supplementation on changes in the intestinal microbiome, intestinal short-chain fatty acids production, and trace element absorption in older laying hens, with consequent effects on egg performance and shell quality. We used the same hens as their own control; a total of 720 laying hens aged 422 days were randomly divided into three replicates, with the CON group fed a commercial diet at 422–441 days of age and the HANa group fed a commercial diet supplemented with 0.05% sodium humate at 442–461 days of age. Compared with the CON group, in the HANa group, Bacteroidetes and Actinobacteria were significantly increased, whereas, Firmicutes was significantly decreased. Further, Veillonella, Enterococcus, Lactobacillus, and Turricibacter significantly decreased, and Peptoniphilus, Helcococcus, GW-34, Psychrobacter, Anaerococcus, Corynebacterium, Facklamia, Trichococcus, Gallicola, Clostridium, and Oscillospira were significantly increased. The results showed that sodium humate significantly altered the alpha and beta diversity and changed the structure of the intestinal microbiome. Acetic acid, isovaleric acid, and isobutyric acid, among short-chain fatty acids were significantly increased in the HANa group, whereas trace elements such as Mn, Zn, and Fe were significantly reduced. The eggshell strength and ultrastructure were significantly altered. In this study, sodium humate was found to alter the intestinal microbiome structure of aged hens, change the production of short-chain fatty acids, and promote the absorption of trace elements to keep aged hens from experiencing a decrease in egg production performance.

Mitigative Potential of Novel <i>Lactobacillus plantarum</i> TISTR 2076 against the Aflatoxins-Associated Oxidative Stress and Histopathological Alterations in Liver and Kidney of Broiler Chicks during the Entire Growth Period

Aflatoxins are the secondary metabolites produced by <i>Aspergillus flavus</i> and <i>Aspergillus parasiticus</i> and have severe pathological effects on the health of human and animals. The present study was designed to investigate the toxicopathological changes induced by aflatoxins and mitigative potential of <i>Lactobacillus plantarum</i> in broiler birds. One hundred and eighty broiler chicks at one day of age was procured from the local market, and chicks were equally divided into six groups with thirty birds in each group. These birds were treated with aflatoxins (300 and 600 µg/kg) and <i>Lactobacillus plantarum</i> (1 × 10⁸ cfu/kg of feed) in different combinations. The first group was kept as the control, and only a basal diet was provided to birds (BD). In the second group (AF1), the first level of aflatoxins (300 µg/kg) was fed to the birds. In the third group (AF2), the second level of aflatoxins (600 µg/kg) was fed to birds. In the fourth group (AF1LP), <i>Lactobacillus plantarum</i> was given with first level of aflatoxins. In the fifth group (AF2LP), <i>Lactobacillus plantarum</i> was given with the second level of aflatoxins, and in the 6th group (BDLP), <i>Lactobacillus plantarum</i> alone was fed to the chicks. This experimental study was continued for 42 days. Birds were slaughtered after 42 days, and different parameters were assessed. Parameters studied were gain in body weight, organ weight along with some histopathological, hematological, biochemical parameters and residues of aflatoxins in liver and kidney. <i>Lactobacillus plantarum</i> improved the body weight gain and restored the relative organ weight. Hepatic and renal biomarkers returned to normal concentrations, serum proteins were restored in combination group AF1LP, and partial amelioration was observed in the AF2LP group. Red blood cells, white blood cells, hemoglobin centration and packed cell volume became normalized in the AF1LP group, while partial amelioration was observed in the AF2LP group. LP also reduced the concentration of aflatoxin residues in liver kidney and improved the TAC concentrations. The results of this study elucidated the mitigative potential of <i>Lactobacillus plantarum</i> against serum biochemical, histopathological, hematological and toxicopathological changes induced by aflatoxins in the chicks.

Effects of synbiotic on growth, digestibility, immune and antioxidant performance in broilers

The overuse of in-feed antibiotics has been associated with serious issues, including the developing of antibiotic-resistant pathogens and causing drug residues in poultry products. To date, many countries have restricted the use of growth-promoting antibiotics in food animals, resulting in the increased need for effective alternatives to in-feed antibiotic. Synbiotics, which are composed of probiotics and prebiotics, have been shown to act synergistically when applied simultaneously. Thus, this study investigated the effects of a synbiotic, composed of microencapsulated Lactobacillus plantarum (MLP) and fructooligosaccharide (FOS), on growth, immune and antioxidant parameters, and digestibility of calcium and phosphorus in broilers. A total of 168 newly hatched male broilers were randomly allotted to three dietary groups (n = 7): (1) a corn-soybean meal basal diet (CON); (2) basal diet + synbiotic (SYN); and (3) basal diet + aureomycin (ANT). Compared with the CON, chickens had greater average daily gain and digestibility of calcium and phosphorus in the SYN group (P < 0.05). In the SYN and ANT group, serum IgA, IgG, and IL-10 levels were higher, while the serum TNF-α, IL-2, and IL-6 levels were reduced (P < 0.05) compared to CON. Compared with CON, the level of serum malondialdehyde was lower (P < 0.05) and SOD level was higher (P < 0.05) in either SYN or ANT group. No significant differences in populations of Escherichia coli were seen in chickens among the three groups, whereas, the populations of Lactobacillus were higher (P < 0.05) in chickens in the SYN group compared with those in CON and ANT groups. Taken together, the addition of SYN, consisting of MLP and FOS, had benefits on growth, immune and antioxidant parameters, and digestibility of calcium and phosphorus, indicating its potential to serve as a substitute for antibiotics in broiler feeding.

Effects of Probiotics on the Growth Performance, Antioxidant Functions, Immune Responses, and Caecal Microbiota of Broilers Challenged by Lipopolysaccharide

We aimed to study the effects of dietary Bacillus coagulans (B. coagulans) and Lactobacillus plantarum (L. plantarum) on broilers challenged by Escherichia coli lipopolysaccharide (LPS). One-day-old Cobb 500 chicks (360) were divided randomly into three treatment groups for 47 days: no supplementation (control, CON), B. coagulans supplementation (BC), and L. plantarum supplementation (LA). Broilers were routinely fed for 42 days and intraperitoneally injected with 500 μg LPS per kg body weight at 43, 45, and 47 days of age, respectively. Samples were collected 3 h after the last injection. At 1-21 days of age, the ADG in the BC and LA groups was higher than that in the CON group, and the feed to gain ratio (F/G) in the BC group was significantly decreased (P < 0.05). Compared with that in CON birds, the ADG was increased and the F/G was decreased in the BC and LA birds at 22-42 and 1-42 days of age, respectively (P < 0.05). After LPS stimulation, the endotoxin (ET), diamine oxidase (DAO), and D-lactic acid (D-LA) levels in the BC group were lower than those in the CON group (P < 0.05). The IgY, IgA, and IgM contents in the BC group and the IgY and IgM contents in the LA group were higher than those in the CON group (P < 0.05). The pro-inflammatory factor and interferon-β (IFN-β) contents (P < 0.05) decreased, and the anti-inflammatory factor content in the serum (P < 0.05) increased in the BC and LA groups. Compared with the CON and LA treatments, the BC treatment increased the concentrations of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT), and decreased that of malondialdehyde (MDA) (P < 0.05). In contrast with the CON treatment, the BC and LA treatments increased the abundance of Ruminococcaceae and reduced that of Desulfovibrio (P < 0.05). Moreover, BC increased the abundance of beneficial bacteria. Overall, supplementation with B. coagulans and L. plantarum promoted the growth of broilers, improved their immunity and antioxidant capacity, and alleviated the LPS-stimulated inflammatory response by regulating the intestinal flora.

Effect of Dietary Bacillus licheniformis Supplementation on Growth Performance and Microbiota Diversity of Pekin Ducks

This experiment was conducted to investigate the effects of different concentrations of Bacillus licheniformis (B. licheniformis) on growth performance and microbiota diversity of Pekin ducks. Three hundred 1-day-old healthy Pekin ducks were randomly divided into 5 groups with 6 replicates per group and 10 ducks per replicate. The five treatments supplemented with basal diets containing: either 0 (group CON), 200 (group LLB), 400 (group MLB), and 800 (group HLB) mg/kg B. licheniformis or 150 mg/kg aureomycin (group ANT) for 42 days, respectively, and were sacrificed and sampled in the morning of the 42nd day for detection of relevant indexes. The results showed as follows: The feed conversion ratio of the LLB group and MLB groups were lower than the CON group (P < 0.05). The body weight and average daily feed intake of the MLB group were significantly higher than that of the CON group and ANT group (P < 0.05). Compared with the CON group, the MLB group significantly increased the content of IgA (P < 0.05) and proinflammatory IL-6 were significantly decreased (P < 0.05), besides, the activity of SOD and T-AOC were also significantly increased in the MLB group (P < 0.05). The 16S rRNA analysis showed that B. licheniformis treatments had no effect (P > 0.05) on the alpha diversities of the intestine. The addition of B. licheniformis had a dynamic effect on the abundance of cecal microflora of Pekin ducks, and 1-21 d increased the diversity of microflora, while 21d-42 d decreased it. Compared with the CON group, the relative abundance of Epsilonbacteraeota in the MLB group was significantly increased on Day 21 (P < 0.05), and that of Tenericutes in the LLB group was significantly increased as well (P < 0.05). At 42 d, the relative abundance of Bacteroidetes in LLB, MBL, HBL, and ANT groups was significantly increased (P < 0.05). In addition, the addition of B. licheniformis increased the amount of SCAF-producing bacteria in the intestinal microbiota, such as Lachnospiraceae, Collinsella, Christensenellaceae, and Bilophila. The PICRUSt method was used to predict the intestinal microbiota function, and it was found that lipid transport and metabolism of intestinal microbiota in the MLB group were significantly affected. Overall, these results suggest diet supplemented with B. licheniformis improved growth performance, immune status, antioxidant capacity, and modulated intestinal microbiota in Pekin ducks. The optimal dietary supplement dose is 400 mg/kg.

Effects of Antimicrobial Peptide Microcin C7 on Growth Performance, Immune and Intestinal Barrier Functions, and Cecal Microbiota of Broilers

Microcin C7 is an antimicrobial peptide produced by Escherichia coli, composed of a heptapeptide with a modified adenosine monophosphate. This study was performed to evaluate the effects of Microcin C7 as a potential substrate to traditional antibiotics on growth performance, immune functions, intestinal barrier, and cecal microbiota of broilers. In the current study, 300 healthy Arbor Acres broiler chicks were randomly assigned to one of five treatments including a corn-soybean basal diet and basal diet supplemented with antibiotic or 2, 4, and 6 mg/kg Microcin C7. Results showed that Microcin C7 significantly decreased the F/G ratio of broilers; significantly increased the levels of serum cytokine IL-10, immunoglobulins IgG and IgM, and ileal sIgA secretion; significantly decreased the level of serum cytokine TNF-α. Microcin C7 significantly increased villus height and V/C ratio and significantly decreased crypt depth in small intestine of broilers. Microcin C7 significantly increased gene expression of tight junction protein Occludin and ZO-1 and significantly decreased gene expression of pro-inflammatory and chemokine TNF-α, IL-8, IFN-γ, Toll-like receptors TLR2 and TLR4, and downstream molecular MyD88 in the jejunum of broilers. Microcin C7 significantly increased the number of Lactobacillus and decreased the number of total bacteria and Escherichia coli in the cecum of broilers. Microcin C7 also significantly increased short-chain fatty acid (SCFA) and lactic acid levels in the ileum and cecum of broilers. In conclusion, diet supplemented with Microcin C7 significantly improved growth performance, strengthened immune functions, enhanced intestinal barrier, and regulated cecal microbiota of broilers. Therefore, the antimicrobial peptide Microcin C7 may have the potential to be an ideal alternative to antibiotic.

Probiotic Characteristics of Lactiplantibacillus Plantarum N-1 and Its Cholesterol-Lowering Effect in Hypercholesterolemic Rats

In this study, the probiotic potential and treatment effects of Lactiplantibacillus plantarum N-1 in hypercholesterolemic rats were investigated, and the possible regulatory mechanisms of lipid metabolism via short-chain fatty acids (SCFAs) and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase were elucidated. The strain N-1 displayed probiotic properties of antioxidant capacity, adhesion to Caco-2 cells, susceptibility to antibiotics in vitro. The results in animal study showed that the total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels in serum and TC in liver declined significantly in both N-1 and simvastatin (Sta) treatment groups compared to the control (P < 0.05), and the extent of these decreases were similar between them. The expression of the HMG-CoA gene in the N-1 group was downregulated significantly by 31.18% compared to the control (P < 0.01), and the contents of butyrate and valerate in N-1 groups were significantly higher than those in both model and Sta group (P < 0.05). Thus, promoting the production of the intestinal SCFAs and inhibiting the expression of HMG-CoA reductase by L. plantarum N-1 may contribute to the improved lipid metabolism and thus lowering cholesterol level in rats. Our investigation indicated that L. plantarum N-1 has the potential to be developed into a functional food supplement for hypercholesterolemia treatment.

Effects of Compound Probiotics on Cecal Microbiome and Metabolome of Shaoxing Duck

This experiment was conducted to investigate the effects of compound probiotics on intestinal microflora and metabolome of Shaoxing ducks. A total of 640 1-day-old Shaoxing ducks were randomly divided into two treatments with eight replicates and forty ducks for each replicate. The ducks were fed basal diet (Ctrl) and basal diet supplemented with 0.15% compound probiotics (MixP). The experiment lasted for 85 days. The results showed that the abundance of Bacteroidetes and Bacteroides in MixP was higher than that in Ctrl (P < 0.05). However, the abundance of Firmicutes and Oscillospira and Desulfovibrio in MixP was lower than that in Ctrl (P < 0.05). Concentrations of 71 metabolites differed significantly (P < 0.05) between the MixP and the Ctrl groups; for example, Pyridoxal (Vitamin B6), L-Arginine, and Betaine aldehyde were up-regulated (P < 0.05), and 7-oxocholesterol, 3-hydroxy-L-kynureni-ne, and N-acetyl-d-glucosamine were down-regulated (P < 0.05). KEGG was enriched in 15 metabolic pathways. The pathways of Vitamin B6 metabolism, Vascular smooth muscle contraction, Vitamin digestion and absorption, and Protein digestion and absorption were influenced by compound probiotics supplementation. Thus, supplementation of compound probiotics improved cecal heath through shifts in the cecal microbiome and metabolome.

Biological Function of Short-Chain Fatty Acids and Its Regulation on Intestinal Health of Poultry

Short-chain fatty acids (SCFAs) are metabolites generated by bacterial fermentation of dietary fiber (DF) in the hindgut. SCFAs are mainly composed of acetate, propionate and butyrate. Many studies have shown that SCFAs play a significant role in the regulation of intestinal health in poultry. SCFAs are primarily absorbed from the intestine and used by enterocytes as a key substrate for energy production. SCFAs can also inhibit the invasion and colonization of pathogens by lowering the intestinal pH. Additionally, butyrate inhibits the expression of nitric oxide synthase (NOS), which encodes inducible nitric oxide synthase (iNOS) in intestinal cells via the PPAR-γ pathway. This pathway causes significant reduction of iNOS and nitrate, and inhibits the proliferation of Enterobacteriaceae to maintain overall intestinal homeostasis. SCFAs can enhance the immune response by stimulating cytokine production (e.g. TNF-α, IL-2, IL-6, and IL-10) in the immune cells of the host. Similarly, it has been established that SCFAs promote the differentiation of T cells into T regulatory cells (Tregs) and expansion by binding to receptors, such as Toll-like receptors (TLR) and G protein-coupled receptors (GPRs), on immune cells. SCFAs have been shown to repair intestinal mucosa and alleviate intestinal inflammation by activating GPRs, inhibiting histone deacetylases (HDACs), and downregulating the expression of pro-inflammatory factor genes. Butyrate improves tight-junction-dependent intestinal barrier function by promoting tight junction (TJ) assembly. In recent years, the demand for banning antibiotics has increased in poultry production. Therefore, it is extremely important to maintain the intestinal health and sustainable production of poultry. Taking nutrition strategies is important to regulate SCFA production by supplementing dietary fiber and prebiotics, SCFA-producing bacteria (SPB), and additives in poultry diet. However, excessive SCFAs will lead to the enteritis in poultry production. There may be an optimal level and proportion of SCFAs in poultry intestine, which benefits to gut health of poultry. This review summarizes the biological functions of SCFAs and their role in gut health, as well as nutritional strategies to regulate SCFA production in the poultry gut.

Proteome changes upon in ovo stimulation with Lactobacillus synbiotic in chicken liver

The liver, as the main metabolic organ, plays a key role in many vital processes, including nutrient metabolism, fat digestion, blood protein synthesis, and endocrine management. As one of the immune organs, it has a remarkable ability to adequately activate the immune cells in response to metabolic signals. The anatomy of the liver ensures its close interaction with the gut so that nutrients and gut microbiota contribute to normal metabolism. In chickens, the intestinal microbiota plays an important role in supporting health and improving production parameters. The most effective method of stimulating the microbiota is to administer an appropriate bioactive compound during embryonic development. In ovo stimulation on d 12 of egg incubation involves the delivery of the substance into the air chamber. The aim of the study was to analyze the changes at the protein level after in ovo administration of the synbiotic on d 12 of egg incubation. Our study is the first to conduct a proteome analysis in liver after the administration of a Lactobacillus synbiotic in ovo. Eggs of broiler chickens were injected with a synbiotic—Lactobacillus plantarum with raffinose family oligosaccharides (RFO). On d 21 posthatching liver was collected. We performed analyses based on two-dimensional electrophoresis, matrix-assisted laser desorption/ionization (MALDI) time-of-flight, and MALDI Fourier-transform ion cyclotron resonance to obtain a global view of the hepatic proteome changes in response to in ovo injection. A representative pattern of significantly altered liver proteins was observed after stimulation with the synbiotic. A total of 16 protein spots were differentially expressed, with 5 downregulated and 11 upregulated spots. We conclude that the in ovo synbiotic treatment had the potential to accelerate the major energy-yielding metabolic pathways in the liver of adult broilers.

Lactic Acid Bacteria - A Promising Tool for Controlling Chicken Campylobacter Infection

Since 2005, campylobacteriosis has been the most common zoonotic disease in Europe. The main reservoir of pathogenic Campylobacter strains is broilers, which makes raw and undercooked poultry meat two major sources of disease. Infection in chicken flocks is most often asymptomatic, despite a high level of colonization reaching 106-109cfu/g in animal ceca. It is widely believed that controlling the level of colonization of the birds' digestive tract by pathogenic strains is a good way to increase food safety. Many treatments have been proposed to combat or at least reduce the level of colonization in animals reservoirs: probiotics, bacteriophages, vaccines, and anti-Campylobacter bacteriocins. This review focuses on the effects of Campylobacter infection on the chicken microbiome and colonization control strategies using probiotics (mostly lactic acid bacteria, LAB), which are live microorganisms included in the diet of animals as feed additives or supplements. Probiotics are not only an alternative to antibiotics, which were used for years as animal growth promoters, but they also constitute an effective protective barrier against excessive colonization of the digestive system by pathogenic bacteria, including Campylobacter. Moreover, one of the many beneficial functions of probiotics is the ability to manipulate the host's microbiota. Recently, there have also been some promising attempts to use lactic acid bacteria as a delivery system of oral vaccine against Campylobacter. Recombinant LAB strains induce primarily a mucosal immune response against foreign antigens, accompanied by at most a low-level immune response against carrier strains. Since the main barrier against the invasion of pathogens in the gastrointestinal tract is the intestinal mucosal membrane, the development of effective oral vaccines to protect animals against enteric infection is very reasonable.

Hepatoprotective effects of Lactobacillus plantarum 299v supplemented via drinking water against aflatoxin-induced liver damage

The aim of this study was to examine the impact of intake of a lactic acid bacterium, Lactobacillus plantarum 299v (Lp299v) on aflatoxin-induced hepatotoxicity in broilers. For this, broilers were intoxicated with dietary aflatoxins and simultaneously treated with live Lp299v in drinking water. One-day-old male broilers were divided into eight groups (n = 10/group) as follows. Aflatoxin groups fed basal diet contaminated with aflatoxins (200 or 2000 ppb). The probiotic groups received drinking water enriched with live (Lp299v) (10⁸ CFU/ml). A group of birds was given a commercial mycotoxin binder (2.5 g/kg feed). Control groups received basal diet without probiotic or aflatoxin binder. The growth performance was calculated for the entire period (0-42 days), and blood and liver specimens were processed for histology and determination of liver damage markers. Results showed extensive damage including bile duct hyperplasia, hepatocellular ballooning, and necrosis in chickens fed aflatoxin alone. However, liver lesions were limited to lobular inflammation and pyknosis in broilers treated with aflatoxins along with Lp299v. The histology of the liver tissues from the birds on aflatoxin-free diet + probiotic appeared to be normal when compared to the respective controls. Histopathological indices in different experimental groups were corroborated with the liver damage markers namely, serum ALT, AST, LD, and γ-GT. It is concluded that the improvement in the growth performance and prevention of aflatoxin-related liver lesions could be mainly assigned to the probiotic therapy for the entire period of breeding, although the aflatoxin-binding ability of the Lp299v in inactivation of aflatoxins cannot be ruled out.RESEARCH HIGHLIGHTS Aflatoxin-related liver damage progression was inhibited by probiotics in broilers.Aflatoxin inactivation by probiotics can be assessed by liver histopathology.Growth performance in broilers was improved following the intake of probiotics.

Probiotic Paenibacillus polymyxa 10 and Lactobacillus plantarum 16 enhance growth performance of broilers by improving the intestinal health

With the ever-growing strict prohibitions on antibiotic growth promoters (AGP) in animal production, in-feed probiotics are becoming attractive alternatives to antibiotics in the poultry industry. To investigate the effects of Paenibacillus polymyxa 10 and Lactobacillus plantarum 16 on the growth performance and intestinal health of broilers, 540 male Cobb 500 broilers of 1 d old were randomly divided into 3 groups with 6 replicates per group and 30 chicks per replicate. Broilers were fed with either a basal diet or basal diets supplemented with 1 × 108 colony-forming units (CFU)/kg P. polymyxa 10 (BSC10) or L. plantarum 16 (Lac16) for 42 d. Results showed that Lac16 treatment improved (P < 0.05) the growth performance (body weight and feed conversion) of broilers at the starter phase, while BSC10 treatment slightly improved (P > 0.05) the growth performance of the starter phase broilers. The increased villus height (P < 0.05) at d 14, 21 and 42 and villus height to crypt depth ratio (P < 0.05) at d 14 and 21 were observed in the ileum of the 2 probiotic groups. Besides, transmission electron microscopy results showed that the 2 probiotics enhanced the intestinal epithelial barrier. Both probiotic treatments up-regulated (P < 0.05) the mRNA expression of fatty acid binding protein 1 (FABP1) and sodium-dependent glucose transporters-1 (SGLT-1) in the ileal mucosa of broilers at d 21. In addition, BSC10 and Lac16 treatments significantly (P < 0.05) increased the relative abundance of short-chain fatty acids-producing bacteria, such as Butyricicoccus pullicaecorum, Faecalibacterium prausnitzii, Lachnospira and Coprococcu, and significantly (P < 0.05) decreased the relative abundance of enteric pathogens (Escherichia coli, Bacteroides fragilis and Shigella sonnei). Furthermore, the 2 probiotic treatments also increased the positive connection among the intestinal microbes and the carbohydrate metabolism-related pathways of the intestinal bacteria (P < 0.05), with decreasing (P < 0.05) nucleotides biosynthesis-related pathways of the intestinal bacteria. Overall, these results suggest that the 2 probiotics, especially Lac16, have a potential beneficial effect on the growth performance and intestinal health of starter phase broilers.

The effect of Candida famata and Lactobacillus plantarum on the number of coliforms and the antibiotic resistance and virulence of Escherichia coli in the gut of broilers

This study was undertaken to determine the effect of a yeast (Candida famata) and a bacterium (Lactobacillus plantarum), administered alone or in combination in the drinking water, on the population of yeast, Lactobacillus sp. and coliforms, and the prevalence of antimicrobial resistance (AMR) and virulence genes in Escherichia coli (E. coli) isolated from digesta samples taken throughout the life of broiler chickens. Male (Ross 308) day-old chicks (220) were used. C. famata (isolated from a chicken) and L. plantarum (isolated from a pig) were administered via the drinking water. Water was provided either untreated or with C. famata (CF; 10⁸/ml), L. plantarum (LP; 10⁵-10⁸/ml), or a combination of CF and LP (10⁶-10⁸/ml) in water hoppers on 2 days each week for 35 days. Administering probiotics did not affect the growth performance in broiler chickens. No significant interactions were observed between main effects, and neither CF nor LP had any effect on the population size of Lactobacillus sp. or coliforms. The administration of C. famata increased the population density of yeasts in the small intestine at these ages. The population density of coliforms, Lactobacillus sp. and yeast decreased with age (P < 0.001). There was no significant effect of probiotics on the prevalence of phenotypic AMR and virulence genes in these studies. The prevalence of E. coli that was resistant to ampicillin and tetracycline, as well as carrying ≥3 virulence-associated genes, was greatest at the end of the starter phase (around 8 days old), before declining through the grower and finisher phases. There was only limited evidence that administering either CF or LP affected either the AMR or the virulence of E. coli in the bird. However, tetracycline resistance in E. coli was associated (P < 0.001, P < 0.01, P < 0.05, and P < 0.05) with the carriage of the iron uptake systems of E. coli D, iron-repressible protein, increased serum survival and temperature-sensitive haemagglutinin genes respectively, suggesting that the accumulation of iron and the genetic element conferring tetracycline resistance may be intertwined.

Effects of Bacillus amyloliquefaciens Instead of Antibiotics on Growth Performance, Intestinal Health, and Intestinal Microbiota of Broilers

The aim of this study was to evaluate the dietary effects of Bacillus amyloliquefaciens SC06 (SC06) instead of antibiotics on the growth performance, intestinal health, and intestinal microbiota of broilers. A total of 360 30-day-old Lingnan yellow broilers were randomly allocated into two groups with six replicates per group (30 birds per replicate). The broilers were fed either a non-supplemented diet or a diet supplemented with 10⁸ colony-forming units lyophilized SC06 per kilogram feed for 30 days. Results showed that SC06 supplementation had no effect on the growth performance compared with that of the control group. SC06 treatment significantly (P <0.05) increased the total antioxidant capacity (T-AOC), total superoxide dismutase (T-SOD) activity in the liver, and the activities of trypsin, α-amylase (AMS), and Na⁺K⁺-ATPase in the ileum, whereas it decreased (P < 0.05) lipase, gamma glutamyl transpeptidase (γ-GT), and maltase activities in the ileum. Meanwhile, SC06 treatment also improved the immune function indicated by the significantly (P < 0.05) increased anti-inflammatory cytokine [interleukin (IL)-10] level and the decreased (P < 0.05) pro-inflammatory cytokine [IL-6 and tumor necrosis factor (TNF)-α] levels in the ileum. Furthermore, we also found that SC06 enhanced the intestinal epithelial intercellular integrity (tight junction and adhesion belt) in the ileum. Microbial analysis showed that SC06 mainly increased the alpha diversity indices in the jejunum, ileum, and cecum. SC06 treatment also significantly (P < 0.05) increased the abundances of Bacteroidetes, Bacteroidales, Bacteroides, Fusobacteria, Clostridiaceae, and Veillonellaceae in the cecum and simultaneously decreased the abundances of Planococcaceae in the duodenum, Microbacteriaceae in the jejunum, and Lachnospiraceae, [Ruminococcus] and Ruminococcus in cecum. In conclusion, these results suggested that B. amyloliquefaciens instead of antibiotics showed a potential beneficial effect on the intestinal health of broilers.

Effect of Selenium Sources on Laying Performance, Egg Quality Characteristics, Intestinal Morphology, Microbial Population and Digesta Volatile Fatty Acids in Laying Hens

The use of toxic and less bioavailable inorganic selenium can now be supplemented with an alternative organic source from bacterial species in nutrition for human and animal benefit. This study investigated the effects of selenium sources on laying performance, egg quality characteristics, intestinal morphology, caecum microbial population, and digesta volatile fatty acids in laying hens. One hundred and forty-four Lohman Brown Classic laying hens, at 23 weeks of age, were divided into four experimental groups (36 hens in each), differing in form of Se supplementation: no Se supplementation (Con), 0.3 mg/kg of inorganic Se in the form of sodium selenite (Na2SeO3), 0.3 mg/kg of organic Se from selenium yeast (Se-Yeast), and 0.3 mg/kg of organic Se from Stenotrophomonas maltophilia (bacterial organic Se, ADS18). The results showed that different dietary Se sources significantly affected laying rate, average egg weight, daily egg mass, feed conversion ratio (FCR), and live bodyweight (LBW) (p < 0.05). However, average daily feed intake and shell-less and broken eggs were unaffected (p > 0.05) among the treatment groups. The findings revealed that selenium sources had no (p > 0.05) effect on egg quality (external and internal) parameters. However, eggshell breaking strength and Haugh unit were significantly (p < 0.05) improved with organic (ADS18 or Se-yeast) Se-fed hens compared to the control group. In addition, egg yolk and breast tissue Se concentrations were higher (p < 0.05) in the dietary Se supplemented group compared to the control. Intestinal histomorphology revealed that hens fed ADS18 or Se-Yeast groups had significantly (p < 0.05) higher villi height in the duodenum and jejunum compared to those fed Na2SeO3 or a basal diet. However, when compared to organic Se fed (ADS18 or Se-Yeast) hens, the ileum villus height was higher (p < 0.05) in the basal diet group; with the lowest in the SS among the treatment groups. A significant increase (p < 0.05) of Lactobacilli spp. and Bifidobacteria spp., and a decrease of Escherichia coli and Salmonella spp. population were observed in the organic (ADS18 or Se-yeast) compared to inorganic supplemented and control hens. The individual digesta volatile fatty acid (VFA) was significantly different, but with no total VFA differences. Thus, bacterial selenoprotein or Se-yeast improved the performance index, egg quality characteristics, egg yolk and tissue Se contents, and intestinal villus height in laying hens. Moreover, caecum beneficial microbes increased with a decrease in the harmful microbe population and affected individual cecal volatile fatty acids without affecting the total VFA of the laying hens digesta.

Modulatory Effects of Bacillus subtilis on the Performance, Morphology, Cecal Microbiota and Gut Barrier Function of Laying Hens

We investigated the efficacy of a single bacterium strain, Bacillus subtilis (B. subtilis) YW1, on the performance, morphology, cecal microbiota, and intestinal barrier function of laying hens. A total of 216 28-week-old Hy-line Brown laying hens were divided into three dietary treatment groups, with six replicates of 12 birds each for 4 weeks. The control group (Ctr) was fed a basal diet and the treatment groups, T1 and T2, were fed a basal diet supplemented with B. subtilis at a dose rate of 5 × 108 CFU/kg and 2.5 × 109 CFU/kg, respectively. Dietary supplementation with B. subtilis did not significantly affect overall egg production in both groups, with no obvious changes in average egg weight and intestine morphology. B. subtilis administration also improved the physical barrier function of the intestine by inducing significantly greater expression levels of the tight junction protein occludin in T1 (p = 0.07) and T2 (p < 0.05). Further, supplementation with B. subtilis effectively modulated the cecal microbiota, increasing the relative level of beneficial bacteria at the genus level (e.g., Bifidobacterium p < 0.05, Lactobacillus p = 0.298, Bacillus p = 0.550) and decreasing the level of potential pathogens (e.g., Fusobacterium p < 0.05, Staphylococcus p < 0.05, Campylobacter p = 0.298). Overall, B. subtilis YW1 supplementation cannot significantly improve the egg production; however, it modulated the cecal microbiota towards a healthier pattern and promoted the mRNA expression of the tight junction protein occludin in laying hens, making B. subtilis YW1 a good probiotic candidate for application in the poultry industry, and further expanding the resources of strains of animal probiotics.

Dietary supplemental xylooligosaccharide modulates nutrient digestibility, intestinal morphology, and gut microbiota in laying hens

This study was conducted to evaluate the prebiotic effects of dietary xylooligosaccharide (XOS) supplementation on performance, nutrient digestibility, intestinal morphology, and gut microbiota in laying hens. In a 12-wk experiment, a total of 288 Hy-Line Brown layers at 50 wk of age were randomly assigned into 3 dietary treatments supplemented with XOS at 0, 200 or 400 mg/kg. Each treatment had 8 replicates with 12 birds each. Hens fed XOS diets showed a lower feed-to-egg ratio during wk 7 to 12 and a higher egg yolk color value in wk 12 compared with those fed the control diet (P < 0.05). Dietary XOS supplementation improved the apparent total tract digestibility of gross energy and nitrogen at the end of the 12th wk (P < 0.05). In addition, a higher villus height-to-crypt depth ratio of the ileum was observed in XOS-added groups (P < 0.05). The high throughput sequencing analysis of bacterial 16S rRNA revealed that dietary XOS supplementation at 200 mg/kg altered cecal microbiota. Alpha diversity analysis illustrated a higher cecal bacterial richness in birds fed with XOS at 200 mg/kg. The composition of cecal microbiota modulated by the XOS addition was characterized by an increased abundance of Firmicutes along with a reduced abundance of Bacteroidetes. At the genus level, dietary XOS supplementation triggered decreases in Bacteroides and Campylobacter concurrent with increases in Lactobacillus and several short chain fatty acid producers including Desulfovibrio, Faecalitalea, Faecalicoccus, and 5 genera of family Lachnospiraceae. Collectively, dietary XOS addition improved the feed conversion ratio by modulating nutrient digestibility and ileal morphology in laying hens, which could be attributed to the enhancement of bacterial diversity and alteration of microbial composition.

The alterations of tracheal microbiota and inflammation caused by different levels of ammonia exposure in broiler chickens

Ammonia (NH3) is a known harmful gas and exists in haze, forming secondary organic aerosols. Exposure to ambient ammonia correlates with the respiratory tract infection, and microbiota in the upper respiratory tract is an emerging crucial player in the homeostatic regulation of respiratory tract infection, and microbiota perturbation is usually accompanied by the inflammatory reactions; however, the effects of different levels of ammonia exposure on tracheal microbiota and inflammation are unclear. A total of 288 22-day-old male Arbor Acres broilers were chosen and divided into 4 groups with 6 replicates of 12 chickens, and respectively exposed to ammonia at 0, 15, 25, and 35 ppm for 21-d trial period. Cytokines (interleukin (IL)-1β, IL-6, and IL-10) in the trachea were measured at the 21 d of exposure to NH3. Tracheal microbiota at the 21 d was analyzed by the 16S rRNA gene analysis. The results showed that an increase in ammonia levels, even in 15 ppm, significantly decreased the alpha diversity and changed the bacterial community structure. Six genera (Faecalibacterium, Ruminococcus]_torques_group, unclassified_f__Lachnospiraceae, Ruminococcaceae_UCG-014, Streptococcus, Blautia) significantly increased, whereas Lactobacillus significantly decreased under different levels of ammonia exposure. We also observed positive associations of Faecalibacterium, Blautia, g__Ruminococcaceae_UCG-014, unclassified_f__Lachnospiraceae and Ruminococcus]_torques_group abundances with tracheal IL-1β concentration. Moreover, an increase in ammonia levels, even in 15 ppm, caused respiratory tract inflammatory injury. The results indicated that 15 ppm ammonia exposure changed the composition of tracheal microbiota that caused the tracheal injury possibly through increasing the IL-1β, which might make the broiler more sensitive to the changes of environment and pathogenic micro-organisms in the poultry house, and may be also a critical value that needs high alertness. Herein, the present experiment also suggested that the standard limit of ammonia concentration in adult poultry house is 15 ppm. This research provides an insight into the relationship between the upper respiratory tract microbiota and inflammation under ammonia exposure.

Effects of Dietary Fiber on Nutrients Utilization and Gut Health of Poultry: A Review of Challenges and Opportunities

Simple Summary

The inclusion of agricultural co-products has been increased to utilize the nutrients in these products available at low cost, but inherently, it adds a high dietary fiber content in the poultry diets. The use of exogenous feed enzymes along with advancements in feed milling, feed formulation, and processing of these non-conventional ingredients to improve their digestibility and utilization have played an emphatic role in boosting their use globally. Despite such developments, the presence of a high level of dietary fibers (DF) acting in an anti-nutritive manner still poses challenges in poultry feeding. Various isolated forms of fiber or feed enzymes to break DF into fermentable substrates are being used extensively to provide potential prebiotics to support beneficial gut microbiota or probiotics to improve the gut health of poultry raised without antibiotic growth promoters (AGP). This review reports and discusses the existing challenges in feeding high-DF feed ingredients to poultry and the opportunities that are available to improve the nutritive value of such non-conventional feed ingredients by adopting various technologies.

Abstract

Many fibrous ingredients incorporated in poultry feed to reduce production costs have low digestibility and cause poor growth in poultry. However, all plant-based fibers are not equal, and thus exert variable physiological effects on the birds, including but not limited to, digestibility, growth performance, and microbial fermentation. Several types of fibers, especially oligosaccharides, when supplemented in poultry diets in isolated form, exhibit prebiotic effects by enhancing beneficial gut microbiota, modulating gut immunity, boosting intestinal mucosal health, and increasing the production of short-chain fatty acids (SCFA) in the gut. Recently, poultry producers are also facing the challenge of limiting the use of antibiotic growth promoters (AGP) in poultry feed. In addition to other alternatives in use, exogenous non-starch polysaccharides digesting enzymes (NSPase) and prebiotics are being used to provide substrates to support the gut microbiome. We also conducted a meta-analysis of different studies conducted in similar experimental conditions to evaluate the variability and conclusiveness in effects of NSPase on growth performance of broilers fed fibrous ingredients. This review presents a holistic approach in discussing the existing challenges of incorporating high-fiber ingredients in poultry feed, as well as strategies to fully utilize the potential of such ingredients in improving feed efficiency and gut health of poultry.

Pretreatment with probiotics ameliorate gut health and necrotic enteritis in broiler chickens, a substitute to antibiotics

Necrotic enteritis (NE) is being considered as one of the most important intestinal diseases in the recent poultry production systems, which causes huge economic losses globally. NE is caused by Clostridium perfringens, a pathogenic bacterium, and normal resident of the intestinal microflora of healthy broiler chickens. Gastrointestinal tract (GIT) of broiler chicken is considered as the most integral part of pathogen's entrance, their production and disease prevention. Interaction between C. perfringens and other pathogens such as Escherichia coli and Salmonella present in the small intestine may contribute to the development of NE in broiler chickens. The antibiotic therapy was used to treat the NE; however European Union has imposed a strict ban due to the negative implications of drug resistance. Moreover, antibiotic growth promoters cause adverse effects on human health as results of withdrawal of antibiotic residues in the chicken meat. After restriction on use of antibiotics, numerous studies have been carried out to investigate the alternatives to antibiotics for controlling NE. Thus, possible alternatives to prevent NE are bio-therapeutic agents (Probiotics), prebiotics, organic acids and essential oils which help in nutrients digestion, immunity enhancement and overall broiler performance. Recently, probiotics are extensively used alternatives to antibiotics for improving host health status and making them efficient in production. The aim of review is to describe a replacement to antibiotics by using different microbial strains as probiotics such as bacteria and yeasts etc. having bacteriostatic properties which inhibit growth of pathogens and neutralize the toxins by different modes of action.