Supplementation of a selected probiotic strain for Campylobacter control in poultry

In Europe, campylobacteriosis is the most common infectious disease transmissible from animals to humans through food and the bacterial species most frequently implicated is Campylobacter jejuni (Humprey et al. 2007). Epidemiological data obtained by the European Food Safety Authority (EFSA) evidenced that poultry meat appears to be a major, if not the largest, source of human infection (Hugas et al., 2009). Risk assessment studies concluded that the most effective intervention measures is the reduction of Campylobacter concentration in poultry, which can effectively reduce the contamination throughout the whole food chain (Nauta et al. 2009). An alternative and effective approach to antibiotic administration to livestock to reduce Campylobacter contamination is the use of probiotics, which have to be carefully selected both to meet the safety requisites established by EFSA and to survive in the feed as well as in the gastro-intestinal tract of the host. The aim of the present work is to select probiotics to be used as additives in feed for livestock poultry in order to reduce C. jejuni contamination and therefore enhance the safety of poultry meat. The first part of the work regarded the screening of 55 lactic acid bacteria and bifidobacteria for desirable properties for their use as probiotics in poultry: anti-microbial activity against C. jejuni strains, survival in simulated gastro intestinal tract (pH 2.5 and 1% bile salts) and food/feed processing conditions (50 and 55 °C); moreover, susceptibility to the most diffused antibiotics was checked. Secondly, the two most interesting strains, namely Lactobacillus plantarum PCS 20 and Bifidobacterium longum PCB 133, were separately administered to poultry by oral gavages to evaluate their capability of colonizing the GI tract and to estimate their effect on C. jejuni population. The results obtained evidenced that B. longum PCB 133 significantly increased in the feces after 15 days administration and its amount was still high after a wash-out period of 6 days. In the same period, C. jejuni concentration in poultry faeces was significantly reduced. Then, B. longum PCB 133 was microencapsulated in a lipid matrix to obtain optimal survival in the feed, coupled with a prebiotic compound and fed to broiler chickens as a synbiotic mixture. C. jejuni concentration faeces was significantly (p<0.05) reduced in chickens administered with the synbiotic mixture. There were no significant differences in animal weight and feed intake between the treated and the control group. The results obtained in this study indicated that suitable probiotic and prebiotic supplements can be selected and used in poultry feed to reduce Campylobacter incidence. References Hugas M., Tsigarida E., Robinson T., Calistri P. (2009) Trends Food Sci Technol 20: 188-193 Humprey T., O’Brien S., Madsen M. (2007) Int J Food Microbiol 117: 237-257 Nauta M., Hill A., Rosenquist H., et al. (2009) Int J Food Microbiol 129: 107-123