Title: Toward biocontrol of avian pathogenic microorganisms in Côte d’Ivoire with selected probiotics belonging to lactic acid and acetic acid bacteria
Abstract:
Excessive use of antibiotics as treatment or preventive agent, as well as growth promoters in animal husbandry, particularly in poultry farming, is one of the most important causes of the emergence of pathogenic bacteria that are increasingly resistant to antibiotics. In animals, this situation is at the origin of therapeutic failure in treatment of various pathologies, notably salmonellosis, colibacillosis and aspergillosis; three pathologies that are responsible for huge economic losses associated with reduction in zootechnical performance of chickens and decline in their general state of health. Among potential sources of contamination feed and poultry litter are cited. The objective of our study is to use probiotic lactic acid bacteria as an alternative to antibiotics in poultry farms in order to prevent pathologies cited above and improve zootechnical performance of the animals, and thus contributes to health and food safety in Côte d'Ivoire. Furthermore, this work plans to improve sanitary conditions of poultry farms by treating the litter with selected acetic bacteria.
Numerous samples collected from feed (164) for farm chickens and litter (360) in the District of Abidjan were submitted to microbiological analysis. They revealed that all litter samples and most of the feed in farms were contaminated with Avian Pathogenic Escherichia coli (APEC), Salmonella and Aspergillus. These potential pathogenic microorganisms were submitted to antagonistic analysis against 267 strains of lactic acid bacteria from cocoa bean fermentation and cassava ferment, and 58 strains of acetic acid bacteria. In addition to those antagonistic effects, other criteria like:acidifying power, tolerance to acidity and resistance to bile salts, were analyzed to select potential best acetic acid starter on one hand; on the other hand, lipolytic and proteolytic enzymes assay were added to the criteria cited above for lactic acid bacteria selection as probiotic candidate.
Result allowed selection of five lactic acid bacteria strains including three Lactobacillus plantarum, one Leuconostoc mesenteroides and one Enterococcus faecium as best potential probiotics; and four acetic acid bacteria strains as best starters. These strains presented high surviving rates and maintained their studied functional properties after freeze-drying and conservation. In addition, the five (5) selected probiotics are effective and improve zootechnical performances of chickens without using antibiotics. Given these advantages, the selected strains could be popularized as potential alternatives to antibiotics to improve sanitary quality of poultry farms in Côte d'Ivoire and elsewhere. These strains can also be used as probiotics in agro-food industries.
Key words: Probiotic, lactic acid bacteria, acetic acid bacteria, poultry feed, litter.
