Probiotic Bacillus amyloliquefaciens H57 ameliorates subclinical necrotic enteritis in broiler chicks by maintaining intestinal mucosal integrity and improving feed efficiency

Abstract

Subclinical necrotic enteritis ( NE ) was induced in broiler chicks using a high dose of Eimeria spp. vaccine in the drinking water on day 9, and Clostridium perfringens ( Cp ) culture mixed in the feed on days 14 and 15. The aim was to evaluate the effects of probiotic Bacillus amyloliquefaciens strain H57 ( H57 ) in preventing NE in chicks. Day-old Ross 308, male broilers were weighed and randomly assigned to 6 treatment groups (6 replicate cages/treatment and 8 birds/cage). Birds in group 1 (control) were fed the basal wheat-soybean diet without H57 or NE infection; in group 2 ( Eimeria ) were treated with Eimeria alone; in group 3 ( Cp ) were treated with Cp alone; in group 4 (NE) received both Eimeria and Cp ; in group 5 (NE-H57) received NE infection and H57; and group 6 (H57) received H57. The basal diet of chicks in groups 5 and 6 was supplemented with H57 at a density of 2 × 10 8 spores/g feed from 1 D of age. On day 21, there were no significant treatment effects on BW and feed intake between control and H57 birds. However, on day 21, the feed conversion ratio of NE-H57 birds was significantly improved when compared with NE birds (1.28 vs. 1.36; P < 0.001). Birds challenged with NE had a higher occurrence of pasty vent than birds infected with either Eimeria , Cp , or NE-H57 (41 vs. 27 vs. 29 vs. 19%, respectively; P < 0.001). Intestinal lesion scores of NE birds were also higher than those of Eimeria , Cp , and NE-H57 birds (5.67 vs. 2.56 vs. 2.78 vs. 2.10, respectively; P < 0.001) and correlated with pasty vent (Pearson's r = 0.56; P < 0.001). Microscopic evaluation showed mucosal damage and necrosis in NE birds. In contrast, villi from NE-H57 birds were normal, with no damage or infiltration with Eimeria or Cp . H57 appears to be effective in challenged birds, as it maintained epithelial barrier integrity and improved feed efficiency.

Avian intestinal ultrastructure changes provide insight into the pathogenesis of enteric diseases and probiotic mode of action

“…In this study, a subclinical avian NE disease model was experimentally induced, and the ultrastructure of ileal mucosa evaluated in chicks supplemented with the probiotic H57. In a previous investigation, it was shown that birds exposed to NE and fed the diet with H57 had a significant improvement in feed utilization compared with the NE birds 21 . This effect could have been due, in part, to maintenance of gut barrier integrity.…”

“…The H57 experimental diet was produced by adding H57 to the basal diet at an average dose of 2.48 × 10 8 CFU/g feed (confirmed by microbiological analysis) and was fed to groups 3 and 4 throughout the experiment. Shini et al 21 has detailed the NE challenge, to which groups 2 and 3 were exposed. Briefly, birds challenged with NE were exposed to a coinfection with a commercially available anti-coccidiosis vaccine containing 4 strains of Eimeria spp.…”

“…The most commonly used model for bacterial intestinal infections in broiler chicks is the NE challenge disease model, and, for the current study, a subclinical NE model was employed. Our recent research demonstrated significant beneficial effects on intestinal mucosa maintenance and improvement of feed efficiency in a subclinical NE disease model in chickens supplemented with the probiotic Bacillus amyloliquefaciens strain H57 (H57) 21 . For the present study, electron microscopy was employed to evaluate intestinal villus ultrastructure and epithelium integrity of 21 day-old chickens exposed to NE and fed the probiotic H57.…”

Enterococcus faecium Modulates the Gut Microbiota of Broilers and Enhances Phosphorus Absorption and Utilization

“…Bone metabolism largely mediates P and Ca metabolism, which are closely related but differ in relation to the endocrine control of absorption and renal reabsorption/excretion [ 33 ]. Dietary P is absorbed and accumulated in the small intestinal mucosa and then released into the blood gradually [ 34 ], where concentrations are maintained by homeostasis [ 35 ], as was evident in the current study.…”

The Probiotic Lactobacillus fermentum Biocenol CCM 7514 Moderates Campylobacter jejuni-Induced Body Weight Impairment by Improving Gut Morphometry and Regulating Cecal Cytokine Abundance in Broiler Chickens

“…These elements could be modulated by factors such as diet, gender, housing conditions and age of birds [ 31 , 32 ]. Probiotic bacteria, including Bacillus , Enterococcus or Lactobacillus strains, have proved to be beneficial for maintaining the integrity of intestinal epithelial cells [ 33 , 34 , 35 , 36 ]; this leads to a superior absorption of nutrients, which ultimately enhances chicken growth performance [ 30 , 37 ]. The present outcomes showed that supplementation of L. fermentum , during the first week of growth, improved morphological parameters in the duodenum, jejunum and ileum, with an overall increase in the average values of villus height, crypt depth and villus height-to-crypt depth ratio.…”