Madridge Journal of Food Technology

ISSN: 2577-4182

International Probiotics and Antimicrobial Proteins Conference
November 6-8, 2017 | Barcelona, Spain

Lactobacilli Probiotics as a Potential Control Strategy for Avian Intestinal Spirochaetosis

Jade Passey

University of Surrey, UK

DOI: 10.18689/2577-4182.a1.003

Download PDF

Brachyspira species are the causative agents of avian intestinal spirochaetosis (AIS). AIS is a gastrointestinal disease whereby Brachyspira colonise the caeca and colo-rectum of poultry, primarily layer hens, resulting in diarrhoeal disease and consequently a 6-10% reduction in egg production, poor egg quality and faecally stained eggs. It is estimated that AIS costs the UK poultry industry £18 million per annum. Prevalence of Brachyspira in the UK has increased significantly in recent years, with up to 90% of free range hens and 74% of barn hens testing positive for Brachyspira species. Furthermore emerging antimicrobial resistance is a concern. Therefore, a better understanding of the pathobiology and novel measures to mitigate this economically important disease are urgently required.

Eight avian Brachyspira isolates from the four clinically relevant species, B. pilosicoli, B. intermedia, B. alvinipulli1 and B. innocens were selected and subjected to genetic and metabolic analysis using the Biology system and next-generation whole genome sequencing, in order to further understand the genus.

Additionally, to investigate the mechanisms by which Lactobacillus may mitigate AIS, sixteen Lactobacillus isolates were isolated from chicken faeces and characterised using 16S rRNA sequencing, biochemistry and next-generation sequencing. Lactobacillus isolates were screened for in vitro antimicrobial activity against Brachyspira species. These studies indicated that the cell free supernatant (CFS) from all Lactobacillus strains significantly inhibited Brachyspira growth in a pH-dependent manner (p ≤0.01). Furthermore, the CFS from three Lactobacillus strains consistently inhibited the growth of all test Brachyspira strains in a pH-independent manner (p ≤0.01). This suggests that the inhibition of Brachyspira is not solely attributed to acidity. Subsequently, nuclear magnetic resonance spectroscopy (NMR) was used to identify metabolites secreted into the CFS which may have the potential to inhibit Brachyspira. In addition to lactic and acetic acid, other metabolites such as acetoin were identified as having potential antimicrobial properties.

Furthermore, these three Lactobacillus isolates were able to physically interact with Brachyspira in order to significantly impair growth and motility (p≤0.05).

Collectively, these data suggest that physical interactions between Lactobacillus and Brachyspira are important factors in mitigation of disease and that secreted compounds from Lactobacillus have inhibitory effects against Brachyspira. Further study to explore these mechanisms is required.