Colibacillosis caused by enterotoxigenic Escherichia coli (E. coli) results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varying degrees of resistance to different antibiotics. Therefore the use of probiotics is becoming accepted as an alternative to antibiotics. In this study, we evaluated the effects of Clostridium butyricum (C. butyricum) on growth performance, immune response, intestinal barrier function, and digestive enzyme activity in broiler chickens challenged with Escherichia coli (E. coli) K88. The chickens were randomly divided into four treatment groups for 28 days. Negative control treatment (NC) consisted of birds fed a basal diet without E. coli K88 challenge and positive control treatment (PC) consisted of birds fed a basal diet and challenged with E. coli K88. C. butyricum probiotic treatment (CB) consisted of birds fed a diet containing 2 × 107 cfu C. butyricum/kg of diet and challenged with E. coli K88. Colistin sulfate antibiotic treatment (CS) consisted of birds fed a diet containing 20 mg colistin sulfate/kg of diet and challenged with E. coli K88. The body weight (BW) and average day gain (ADG) in the broilers of CB group were higher (P < 0.05) than the broilers in the PC group overall except the ADG in the 14-21 d post-challenge. The birds in CB treatment had higher (P < 0.05) concentration of tumor necrosis factor-α (TNF-α) at 3 and 7 d post-challenge, and higher (P < 0.05) concentration of interleukin-4 (IL-4) at 14 d post-challenge than those in the PC treatment group. The concentration of serum endotoxin in CB birds was lower (P < 0.05) at 21 d post-challenge, and the concentrations of serum diamine oxidase in CB birds were lower (P < 0.05) at 14 and 21 d post-challenge than in PC birds. Birds in CB treatment group had higher (P < 0.05) jejunum villi height than those in PC, NC, or CS treatment at 7, 14, and 21 d post-challenge. In comparison to PC birds, the CB birds had lower (P < 0.05) jejunum crypt depth during the whole experiment. The birds in CB or CS treatment group had higher (P < 0.05) activities of amylase and protease at 3, 7, and 14 d post-challenge, and higher (P < 0.05) activity of lipase at 3, 7 d post-challenge than PC birds. In all, these results indicate that dietary supplementation with C. butyricum promotes immune response, improves intestinal barrier function, and digestive enzyme activities in broiler chickens challenged with E. coli K88. There is no significant difference between the C. butyricum probiotic treatment and the colistin sulfate antibiotic treatment. Therefore, the C. butyricum probiotic may be an alternative to antibiotic for broiler chickens.

This study investigated the effects of dietary supplementation with Bacillus subtilis ( B. subtilis ) or Bacillus licheniformis ( B. licheniformis ) on growth performance, immunity, antioxidant capacity, short chain fatty acid (SCFA) production, and the cecal microflora in broiler chickens. In total, 360 male, 1-day-old Cobb 500 birds were randomly divided into 3 groups: the control group was fed a basal diet; the B. subtilis group was fed a basal diet supplemented with 1.5 × 10⁹ CFU/kg B. subtilis; the B. licheniformis group was fed a basal diet supplemented with 1.5 × 10⁹ CFU/kg B. licheniformis. Results showed that chickens supplemented with either B. subtilis or B. licheniformis had comparatively higher (P < 0.05) body weight and average daily gain, whereas no difference (P > 0.05) was observed in feed efficiency. Concentrations of serum IgA, IgY, and IgM, as well as anti-inflammatory IL-10 were significantly increased (P < 0.05), and proinflammatory IL-1β and IL-6 were significantly decreased (P < 0.05) by B. subtilis or B. licheniformis supplementation. Moreover, chickens fed with diets supplemented by either B. subtilis or B. licheniformis had greater antioxidant capacity, indicated by the notable increases (P < 0.05) in glutathione peroxidase, superoxide dismutase, and catalase, along with decrease (P < 0.05) in malondialdehyde. Compared to the control group, levels of SCFA, excluding acetic and propionic acid, in cecal content had improved (P < 0.05) by adding B. licheniformis, and significant increase (P < 0.05) in acetic and butyric acid was observed with B. subtilis supplementation. Microbial analysis showed that both B. subtilis or B. licheniformis supplementation could increase butyrate-producing bacteria such as Alistipes and Butyricicoccus, and decrease pathogenic bacteria such as the Synergistetes and Gammaproteobacteria. In summary, dietary supplemented with B. subtilis or B. licheniformis improved growth performance, immune status, and antioxidant capacity, increased SCFA production, and modulated cecal microbiota in chickens. Moreover, B. licheniformis was more effective than B. subtilis with the same supplemental amount.

The effects of feeding dehydrated Enterococcus faecium on growth performance, immune response, and cecal microflora in broiler chickens challenged wi

We investigated the effects of Clostridium butyricum and Enterococcus faecalis (probiotics) in a piglet model. Weaned piglets (180) were randomly divided into three treatment groups and fed basal diet and basal diet supplemented with 6 × 10⁹ CFU C. butyricum per kg and 2 × 10¹⁰ CFU E. faecalis per kg, respectively. The probiotics improved the final body weight, average daily gain, and feed conversion rate, while they reduced the diarrhea rate. The serum aspartate aminotransferase and alanine aminotransferase activities in probiotic-supplemented piglets were decreased on days 14 and 28. Piglets supplemented with probiotics presented an increased serum immunoglobulin (Ig)M level on day 14 and IgA, IgG, and IgM levels on day 28 compared with control piglets, respectively. Moreover, the probiotics increased the jejunal villus length and jejunal villus height to crypt depth ratio, while they decreased the jejunal crypt depth compared with those of the control. Similarly, an increase in inflammation-related pathway factor expression was observed after probiotic administration. Piglets supplemented with probiotics had a higher concentration of volatile fatty acids in the colonic contents than that in the control. High-throughput sequencing indicated that the probiotics modulated the colon bacterial diversity. Species richness and the alpha diversity index of bacterial samples in probiotic-supplemented piglets were higher than those in the control. Piglets supplemented with C. butyricum presented a considerably high relative abundance of C. butyricum compared with that in the control. Overall, C. butyricum and E. faecalis can promote growth performance, protect the intestinal villi morphology, improve immunity, and optimize the intestinal flora in weaned piglets.

This study evaluated the effects of Bacillus coagulans (B. coagulans) as an alternative to antibiotics on growth performance, antioxidant capacity, immunity function and gut health in broilers. A total of 480 one-day-old broilers were randomly divided into 3 treatments with 8 replicates comprising 20 broilers each. The experiment lasted 42 d. Treatments included: basal diet without antibiotics (NCO); basal diet supplemented with 75 mg/kg chlortetracycline (ANT); basal diet supplemented with 5 × 109 CFU/kg B. coagulans(BC). The B. coagulans enhanced body weight (BW) and average daily gain compared with the NCO group (P < 0.05). However, there were no significant differences in average daily feed intake and feed: gain ratio (F: G) among three groups (P > 0.05). The B. coagulans significantly increased catalase, superoxide dismutase, and glutathione peroxidase levels and reduced malondialdehyde levels (P < 0.05). The serum immunoglobulins (IgA, IgM, and IgY) were significantly higher in the BC group when compared to the NCO and ANT groups (P < 0.05). The B. coagulans also markedly reduced serum levels of proinflammatory factors (IL-1β, IL-6, and TNF-α) and enhanced anti-inflammatory factor (IL-10) concentrations compared with control group (P < 0.05). Moreover, compared with the control group, BC significantly inhibited serum xanthine oxidase activity (P < 0.05). The levels of acetic acid, propionic acid, butyrate, isobutyric acid and valerate in BC group were significantly increased on d 42 compared with the NCO and ANT groups (P < 0.05). Furthermore, BC significantly altered cecal microbiota by reducing Desulfovibrio and Parasutterella, and by increasing Alistipes and Odoribacter (P < 0.05, P < 0.05, P < 0.001, P < 0.01, respectively). In conclusion, dietary B. coagulans, when used as an alternative to antibiotics, improved body weight, average daily gain, antioxidant capacity, immunity function and gut health in broilers.

This study was conducted to investigate the effects of Clostridium butyricumon growth performance, immune function, and cecal microflora in broiler c