Food contamination with salmonella and human health in Kinshasa city, Democratic Republic of Congo (DRC)

Objectives: The objective of this study was to assess the level of salmonella contamination of fish and meat from public markets, meat from butcheries and beef carcasses offered for retail sale in Kinshasa, the capital city of the Democratic Republic of CongoMethodology and results: Salmonella spp. in fish and meat was isolated using the classical technique with a pre-enrichment, enrichment, isolation and identification. The mean number of colonies counted was expressed as log10 colony forming units per gram (log10 cfu/g). The prevalence of Salmonella contamination was 11.1% for fish, 18.3 % for meat from public markets, 14.4 % for meat from the butcheries and 27.5 % for beef carcasses at the public abattoir. The positive rate in the evening was higher than in the morning (p<0.05). The bacterial loads ranged from 2.48 - 9.84 log10 cfu/g.Conclusions and applications: This study revealed salmonella contamination of fishes and meats offered for retail sale in Kinshasa city. The contamination was higher in the evening than in the morning. Salmonella are pathogenic microorganisms significant in food infection and intoxications. Results from this study indicate that the food hygiene is poor demonstrating the importance of controlling this pathogen in food processesKey words: Salmonella, meat, retail sale, abattoir, Democratic Republic of Cong

Optimization of housefly larvae production on pig wastes and brewers’ grains for integrated fish and pig farms in the tropics

Lack of appropriate animal waste management methods in many smallholder farms in the tropics often leads to environmental problems, especially in locations with high population density such as urban and peri-urban areas. On farms integrating pig production to fish farming, manure can be turned into a valuable feed source of high quality protein for fish through housefly larvae and contribute to intensify fish production and reduce cost of fish feed. Three experiments were carried to optimize operating conditions for maggot production on animal wastes and industrial byproducts found in Kinshasa, the capital city of the Democratic Republic of Congo (DRC). The comparisons were: (1) production on pure substrates (manure or brewer’s grains) or mixtures with lysine or blood; (2) exposure time to flies for the insemination of the substrates: and (3) dynamics of larvae production. Mixing brewers’ grains with Lysine or manure and/or blood more than doubled the amount of larvae that were harvested. Brewers’ grains are a good source of energy, but are probably deficient in essential amino acids to support the growth of maggots. It also appears that only the first days of laying eggs are important since no difference was observed between temporary and permanent exposure of the substrates to houseflies. The peak of larvae production was reached 6 days after exposure. The addition of cow blood in increasing doses to a mixture of brewers’ grains and manure linearly increased the production of maggots