Effect of fenugreek seeds and Bacillus-based direct-fed microbials on the growth performance, blood biochemicals, and intestinal histomorphology of broiler chickens.

Background: The objective of the present study was to evaluate the potential synergistic impact of the combination of fenugreek seeds (FS) and Bacillus-based direct-fed microbials (DFM) on growth performance, intestinal health, and hematological parameters of broiler chickens. Methods: A total of 160 one-day-old (Ross 308) broiler chicks were randomly assigned to a 2 × 2 factorial arrangement, with two levels of FS (0 and 5 g/kg) and two levels of Bacillus-DFM (0 and 0.1 g/kg), with five replicates of 8 birds each. Results: The result showed that dietary supplementation of FS at 5 g/kg did not improve the growth performance of broilers but impaired the early growth performance by reducing body weight gain and increasing feed conversion ratio, which was recovered during finisher phase. Dietary supplementation of Bacillus-based DFM at 0.1 g/kg did not affect the performance variables but increased the feed conversion ratio. The interaction of fenugreek seeds and Bacillus-based DFM showed synergistic effects on growth performance during the later stages of production. However, antagonistic effects were observed on the blood parameters and the gut morphology. Conclusion: This study demonstrated that FS and DFM had different effects on the broiler health and production depending on the phase of production. The interaction between FS and DFM revealed synergistic effects on growth performance during the finisher phase, but antagonistic effects on blood parameters and gut morphology. Further studies are needed to elucidate the underlying mechanisms and optimize the dosage and combination of FS and DFM for broiler health and production.

In ovo Administration of Defined Lactic Acid Bacteria Previously Isolated From Adult Hens Induced Variations in the Cecae Microbiota Structure and Enterobacteriaceae Colonization on a Virulent Escherichia coli Horizontal Infection Model in Broiler Chickens.

The effects of in ovo administration of a defined lactic acid microbiota (LAM), previously isolated from adult hens, in the cecae microbiota structure and Enterobacteriaceae colonization after exposure to virulent Escherichia coli during the hatching phase of broiler chickens were evaluated. Embryos inoculated with LAM showed a significant (P < 0.05) reduction of Enterobacteriaceae colonization at day-of-hatch (DOH) and day (d) 7. Furthermore, there was a significant increase in total lactic acid bacteria on DOH, body weight (BW) DOH, BW d7, and d0-d7 BW gain and reduced mortality d0-d7 was observed in the LAM group compared with that in phosphate-buffered saline (PBS) control. The bacterial composition at the family level revealed that the Enterobacteriaceae was numerically reduced, whereas the Ruminococcaceae was significantly increased in the LAM group when compared with that in the PBS control. Moreover, the bacterial genera Proteus and Butyricicoccus and unidentified bacterial genera of family Lachnospiraceae and Erysipelotrichaceae were significantly enriched in the LAM group. In contrast, the Clostridium of the family Peptostreptococcaceae and unidentified genus of family Enterobacteriaceae were significantly abundant in the PBS control group. In summary, in ovo administration of a defined LAM isolated from adult hens did not affect hatchability, improved body weight gain and reduced mortality at d7, induced variations in the cecae microbiota structure and reduced Enterobacteriaceae colonization on a virulent E. coli horizontal infection model in broiler chickens.

Draft Genome Sequence of Clostridium perfringens Strain TAMU, Which Causes Necrotic Enteritis in Broiler Chickens.

Clostridium perfringens causes severe gastrointestinal diseases, which include necrotic enteritis (NE) in chickens, a deadly disease worldwide. We report here the draft genome sequence of Clostridium perfringens strain TAMU, which was used in developing an NE chicken challenge model. This C. perfringens TAMU genome sequence will aid in advancing potential intervention strategies to reduce NE pathogenesis.

Isolation and Identification of Lactic Acid Bacteria Probiotic Culture Candidates for the Treatment of Salmonella enterica Serovar Enteritidis in Neonatal Turkey Poults.

The effect of Lactobacillus spp.-based probiotic candidates on Salmonella enterica serovar Enteritidis (SE) colonization was evaluated in two separate experiments. In each experiment, sixty-one day-of-hatch female turkey poults were obtained from a local hatchery. In both experiments, poults were challenged via oral gavage with 104 cfu/poult of SE and randomly allocated to one of two groups (n = 30 poults): (1) the positive control group and (2) the probiotic treated group. Heated brooder batteries were used for housing each group separately and poults were allowed ad libitum access to water and unmedicated turkey starter feed. 1 h following the SE challenge, poults were treated with 106 cfu/poult of probiotic culture via oral gavage or phosphate-buffered saline （PBS）to control groups. A total of 24 h post-treatment, poults were euthanized and the ceca and cecal tonsils from twenty poults were collected aseptically for SE recovery. In both trials, a significant reduction in the incidence and log10 cfu/g of SE were observed in poults treated with the probiotic when compared with control poults (p ≤ 0.05). The results of the present study suggest that the administration of this lactic acid-producing bacteria (LAB)-based probiotic 1 h after an SE challenge can be useful in reducing the cecal colonization of this pathogen in neonatal poults.

Impact of a Bacillus Direct-Fed Microbial on Growth Performance, Intestinal Barrier Integrity, Necrotic Enteritis Lesions, and Ileal Microbiota in Broiler Chickens Using a Laboratory Challenge Model.

Decreases in the use of antibiotics and anticoccidials in the poultry industry have risen the appearance of necrotic enteritis (NE). The purpose of this study was to evaluate the effect of a Bacillus direct-fed microbial (DFM) on growth performance, intestinal integrity, NE lesions and ileal microbiota using a previously established NE-challenged model. At day-of-hatch, chicks were randomly assigned to three different groups: Negative control (NC), Positive control (PC) challenged with Salmonella Typhimurium (day 1), Eimeria maxima (EM, day 13) and Clostridium perfringens (CP, day 18-19), and Bacillus-DFM group (DFM) challenged as the PC. Body weight (BW) and body weight gain (BWG) were measured weekly. Total feed intake (FI) and feed conversion ratio (FCR) were evaluated at day 21. Liver samples were collected to assess bacterial translocation and blood samples were used to measure superoxide dismutase (SOD) and fluorescein isothiocyanate-dextran (FITC-d). Intestinal contents were obtained for determination of total IgA and microbiota analysis. NE lesion scores (LS) were performed at day 21. Chickens consuming the DFM significantly improved BW and had a numerically more efficient FCR compared to PC at day 21. Additionally, there were no significant differences in FCR between the DFM group and NC. Furthermore, the DFM group showed significant reductions in LS, IgA and FITC-d levels compared to the PC. However, there were no significant differences in SOD between the groups. The microbiota analysis indicated that the phylum Proteobacteria was significantly reduced in the DFM group in comparison to PC. At the genus level, Clostridium, Turicibacter, Enterococcus, and Streptococcus were reduced, whereas, Lactobacillus and Bacillus were increased in the DFM group as compared to PC (p < 0.05). Likewise, the DFM significantly reduced CP as compared to PC. In contrary, no significant differences were observed in bacterial composition between NC vs. DFM. In addition, beta diversity showed significant differences in the microbial community structure between NC vs. PC, and PC vs. DFM. These results suggest that the dietary inclusion of a selected DFM could mitigate the complex negative impacts caused by NE possibly through mechanism(s) that might involve modulation of the gut microbiota.

Evaluation of the antimicrobial and intestinal integrity properties of boric acid in broiler chickens infected with Salmonella enteritidis: Proof of concept.

The objectives of the present study were to evaluate the antimicrobial effect of boric acid (BA) on Salmonella enteritidis colonization, intestinal permeability, total intestinal IgA levels, and cecal microbiota composition in broiler chickens. For this purpose, sixty day-old-chicks were randomly allocated to one of two groups: 1) non-treated control group and 2) 0.1% (w/w) BA in feed. All chicks were challenged with 104 cfu of S. Enteritidis per bird at 1-d old. On day 3 and 10 post-challenge, samples of crop and ceca-cecal tonsils (CCT) were aseptically collected to evaluate overall aerobic and lactic acid bacteria, as well as S. Enteritidis recovery. Blood and intestinal samples were also collected to evaluate intestinal permeability and total intestinal IgA production, respectively. On day 10 post-challenge, the concentration of S. Enteritidis in crop and CCT significantly decreased (P < .05) by 2.60 log10 and 5.26 log10, respectively, in the BA group compared to the control group. Furthermore, chickens treated with 0.1% BA had a significant reduction in serum fluorescein isothiocyanate dextran (FITC-d) concentration and lower total intestinal IgA levels when compared to the control group. Interestingly, in the microbiota analysis, only the abundance of Actinobacteria phylum was significantly lower in the BA group in comparison with the control group and significant differences in beta diversity were also observed between comparing groups. The results of the present study suggest that BA could maintain intestinal homeostasis, as well as the balance in the microbiota due to its effectiveness in controlling S. Enteritidis infection.