Lactobacillus Strain Ecology and Persistence within Broiler Chickens Fed Different Diets: Identification of Persistent Strains

Abstract

Lactobacilli are autochthonous residents in the chicken gastrointestinal tract, where they may potentially be used as probiotics, competitive exclusion agents, or delivery vehicles. The aim of this study was to use an in vivo model to investigate the effect of diet and competing lactic acid bacteria on the colonization of inoculated Lactobacillus strains, with the goal of identifying strains which can consistently colonize or persist for an extended period of several weeks. Chicken-derived Lactobacillus strains were genetically marked with rifampin resistance and administered on day 0 to chickens fed either a normal commercial diet or a specially formulated high-protein diet. Chickens fed the high-protein diet were also coinoculated with two different mixes of additional lactic acid bacteria. Enterobacterial repetitive intergenic consensus sequence-based PCR (ERIC-PCR) was used to identify rifampin-resistant isolates recovered from chickens. Three strains, belonging to the species Lactobacillus agilis, Lactobacillus crispatus, and Lactobacillus vaginalis, were commonly reisolated from the chickens on both diets at days 21 and 42. The ability of these strains to persist was confirmed in a second chicken trial. All three strains persisted throughout the production period in the chickens fed a commercial diet, while only the L. agilis and L. vaginalis strains persisted in the chickens fed the high-protein diet. In both in vivo trials, competing lactic acid bacteria modified representation of the strains recovered, with all three stains capable of competing in the presence of one or both mixes of coinoculated strains. The in vivo model successfully identified three persistent strains that will be characterized further.The ecology of the chicken gastrointestinal tract (GIT) has been studied in depth using both culture-dependent (5,7,21,40) and -independent methods (2,3,7,33,54). These studies have revealed that lactobacilli are autochthonous residents in chickens, where they predominate in the proximal GIT and are present but less abundant within the distal GIT (52). The most commonly identified Lactobacillus species are Lactobacillus crispatus, Lactobacillus reuteri, and Lactobacillus salivarius (1,7,15,26,28). A detailed understanding of the relationship between these bacteria and their host under different dietary and environmental conditions will facilitate the development of lactobacilli for various applications directed toward increasing broiler production efficiency and improving chicken health.Since the withdrawal of antimicrobial growth promoters from chicken feed in Europe, the incidence of necrotic enteritis (NE) has increased (9, 51). Consequently, there is a need to develop alternative methods for controlling the causative agent of NE, Clostridium perfringens, in the chicken GIT. Lactobacilli are excellent candidates for alternative control methods due to their autochthonous nature and dominance of the upper GIT microbiota, particularly within the small intestine where NE occurs. Their potential utility ...

In vitro and in vivo screening of native lactic acid bacteria toward their selection as a probiotic in broiler chickens

“…17 continuously as food additives (Stephenson et al, 2010). PFGE was an appropriate tool to confirm that the strain used was always the same strain.…”

“…One potential advantage of the in vivo assays described here is the ability to track strains throughout the broilers' production period. Rifampicin marking to recover Lactobacillus strains from the native GIT microbiota has been successfully used in broilers (Stephenson et al, 2010;Garriga et al, 1998). The counts showed absence of growth of the intestinal lactic microbiota in MRS rif .…”

Chronic dermatitis caused by Lactobacillus jensenii infection in a blue and gold macaw (Ara ararauna)

“…[8][9][10][11][12][13] Only a few reports 2,8 exist of pathogenic Lactobacillus spp involving avian species. 3,5-7 More than 50 Lactobacillus spp have been identified, several of which have been recovered from avian species.…”

Transformation of, and Heterologous Protein Expression in, Lactobacillus agilis and Lactobacillus vaginalis Isolates from the Chicken Gastrointestinal Tract

“…Bacterial strains used in this study are listed in Table 1. Lactobacillus agilis La3 and L. crispatus Lc9 were originally isolated from the jejuna and L. vaginalis Lv5 was isolated from the crops of chickens fed an experimental high-protein diet (44) and subsequently found to persist in the chicken GIT upon reinoculation (45). Lactobacilli were routinely cultured in MRS broth (Difco, Detroit, MI) and agar at 37°C for 24 and 48 h, respectively, under anaerobic conditions using a BD GasPAK EZ container (Becton Dickinson, Sydney, Australia) with an AnaeroGen sachet (Oxoid Australia, Adelaide, Australia).…”

“…Additionally, lactobacillus delivery vectors could be used to immunize against avian viruses, such as infectious bursal disease, Marek's disease, Newcastle disease, or avian influenza virus. We have recently identified several Lactobacillus strains, Lactobacillus agilis La3, Lactobacillus vaginalis Lv5, and Lactobacillus crispatus Lc9, which are able to colonize and persist within the GIT of chickens fed either a commercial or a highprotein diet (45). These strains show great potential as vectors for the in situ delivery of therapeutic proteins targeting GIT pathogens.…”