Effect of Bacillus amyloliquefaciens-based Direct-fed Microbial on Performance, Nutrient Utilization, Intestinal Morphology and Cecal Microflora in Broiler Chickens.

Xinjian Lei,Yingjun Ru,Xiangshu Piao,Alexandre Péron,Hongyu Zhang,Huifang Zhang

doi:10.5713/ajas.14.0330

Abstract

The present study was conducted to evaluate the effect of the dietary supplementation of Bacillus amyloliquefaciens-based direct-fed microbial (DFM) on growth performance, nutrient utilization, intestinal morphology and cecal microflora in broiler chickens. A total of two hundred and eighty eight 1-d-old Arbor Acres male broilers were randomly allocated to one of four experimental treatments in a completely randomized design. Each treatment was fed to eight replicate cages, with nine birds per cage. Dietary treatments were composed of an antibiotic-free basal diet (control), and the basal diet supplemented with either 15 mg/kg of virginiamycin as antibiotic growth promoter (AGP), 30 mg/kg of Bacillus amyloliquefaciens-based DFM (DFM 30) or 60 mg/kg of Bacillus amyloliquefaciens-based DFM (DFM 60). Experimental diets were fed in two phases: starter (d 1 to 21) and finisher (d 22 to 42). Growth performance, nutrient utilization, morphological parameters of the small intestine and cecal microbial populations were measured at the end of the starter (d 21) and finisher (d 42) phases. During the starter phase, DFM and virginiamycin supplementation improved the feed conversion ratio (FCR; p<0.01) compared with the control group. For the finisher phase and the overall experiment (d 1 to 42) broilers fed diets with the DFM had better body weight gain (BWG) and FCR than that of control (p<0.05). Supplementation of virginiamycin and DFM significantly increased the total tract apparent digestibility of crude protein (CP), dry matter (DM) and gross energy during both starter and finisher phases (p<0.05) compared with the control group. On d 21, villus height, crypt depth and villus height to crypt depth ratio of duodenum, jejunum, and ileum were significantly increased for the birds fed with the DFM diets as compared with the control group (p<0.05). The DFM 30, DFM 60, and AGP groups decreased the Escherichia coli population in cecum at d 21 and d 42 compared with control group (p<0.01). In addition, the population of Lactobacillus was increased in DFM 30 and DFM 60 groups as compared with control and AGP groups (p<0.01). It can be concluded that Bacillus amyloliquefaciens-based DFM could be an alternative to the use of AGPs in broilers diets based on plant protein.

Highlights

Increasing concerns regarding antibiotic resistance and the presence of drug residues in animal products have led several European countries and South Korea to ban the use direct-fed microbials (DFMs) were defined as “live microbial feed supplements which beneficially affect the host animal by improving its intestinal balance” (Fuller, 1989)
For the finisher phase and the overall period (d 1 to 42), chickens fed diets supplemented with Bacillus amyloliquefaciens-based DFM had higher body weight gain (BWG) and better Feed conversion ratio (FCR) than the control (p
The addition of virginiamycin significantly improved BWG, feed intake (FI), and FCR during the finisher and overall period compared to the control group (p

Summary

Introduction

Increasing concerns regarding antibiotic resistance and the presence of drug residues in animal products have led several European countries and South Korea to ban the use DFMs were defined as “live microbial feed supplements which beneficially affect the host animal by improving its intestinal balance” (Fuller, 1989). The supplementation of various DFMs has been shown to diversify and stabilize. The effectiveness of DFMs in animal studies varies greatly depending on the origin of the microbes (Jerzsele et al, 2012)

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Conclusion