IDENTIFICATION OF Lactobacillus sp. ISOLATED FROM CHICKEN GASTROINTESTINAL TRACT WITH ANTAGONISM AGAINST PATHOGENS

BENSALAH F.¹, LAROUCI S.², LABTAR A.³, GUERMOUCHE A.⁴, DELORME C.⁵, PIERRE R.^6
1Laboratoire Génétique Microbienne, Université Es-Sénia, Oran 31000, Algérie.
²Laboratoire Génétique Microbienne, Université Es-Sénia, Oran 31000, Algérie.
³Laboratoire Génétique Microbienne, Université Es-Sénia, Oran 31000, Algérie.
⁴Laboratoire Génétique Microbienne, Université Es-Sénia, Oran 31000, Algérie.
⁵INRA-CRJ, Institut National de la Recherche Agronomique, Micalis Institute, Département de Microbiologie et Chaîne Alimentaire. 78352 Jouy-En-Josas, cedex, France.
⁶INRA-CRJ, Institut National de la Recherche Agronomique, Micalis Institute, Département de Microbiologie et Chaîne Alimentaire. 78352 Jouy-En-Josas, cedex, France.

Received : 19-01-2014     Accepted : 17-02-2014     Published : 06-03-2014
Volume : 3     Issue : 1       Pages : 37 - 41
J Pathol Res 3.1 (2014):37-41

Conflict of Interest : None declared

Antibiotics use had its limitations due to the emergence of new strains caused by multi-resistant misuse of these compounds in the poultry sector. The use of probiotics is necessary to promote healthy microflora antagonistic to pathogens and screws can register as an alternative strategy proposed to protect poultry pathogens and to replace antibiotics as growth factor. The digestive microflora of two Algerian farmer’s cocks were studies to isolate and identify lactic acid bacteria for use as potential probiotic in food animal production in order to protect against animal diseases as alternative to antibiotics. A total of 22 strains were isolated from different compartments as crop, caecum, ileum, jejunum, gizzard and colon to evaluate their probiotic proprieties. A use of specific primers targeting partial regions of 16S rDNA gene and sequencing of the amplified fragments preconized to 480 pb were used to identify isolates belonging to the Lactobacillus genus. The most diagnostic strains by analysis BLAST were Lactobacillus acidophilus, Lactobacillus gallinarum, Lactobacillus crispatus and Lactobacillus johonossi, about 99% of homology for all strains. The study on antagonism cultures of Lactobacillus strains using the disc diffusion method showed inhibitory activity during interactions opposite pathogens including Staphylococcus aureus, Escherichia coli and Salmonella typhi by appearance of clear halos in vitro and twelve of them were selected due to their strong inhibitory action. Furthermore, the inhibitory effect of neutralized cell free supernatants of these isolates was studied and confirmed that the selected strains secreted substances witch are responsible for the antagonistic action observed on the pathogens. In addition, the acidifying power strains were determined by titratable acidity. In long term, these strains, once best characterized, could be proposed as probiotics in poultry feed.