Different processing additives is efficacious on microbial loads and antibiotics sensitivity pattern of giant African land snail (Archachatina marginata)

Résumé

Snails are harvested for food in many parts of the world but are susceptible to environmental contaminations and pollutants due to the continuous ingesting of bacteria from the soil and the environment which they are found. Thus, the study has been designed to investigate the distribution and prevalence of micro-organisms in snails in humid tropics of Nigeria. Fifteen samples of Archachatina marginata were collected from Melege village, Ose local government area, Ondo State, Nigeria. The foot and head were analyzed microbiologically for bacterial loads before and after processing with five cleansing reagents: lime, alum, vinegar, salt and ash. Lime proved most effective reagent for decontaminating snail meats as it had the highest reduction of microbial load after processing (57.1%), followed by salt (44%) and the least was alum (20%). The mean microbial load on the head ranged between 9-22cfu/cm² before and 4-12cfu/cm² after processing, while foot ranged between 13-19cfu/cm² before and 8-14cfu/cm² after processing. Eight isolates belonging to nine genera including Micrococcus luteus [10(21.31%)] most predominant, followed by Escherichia coli [8(13.11%)], Proteus vulgaris [8(13.11%)], Klebsiella spp [6(16.39%)], Bacillus spp [6(9.84%)], Aeromonas spp [5(11.48%)], Streptococcus pyogenes [6(8.2%)], and least was Enterobacter spp [4(6.56%)] respectively. Results showed different pathogenic bacteria in snails. The presence of higher number of pathogenic Klebsiella spp and Escherichia coli among others, encountered in Archachatina marginata is an indication of public health hazard and also a warning signal for possible occurrence of food borne. The result showed lime as the most effective reagent in processing snail meat. The antibiotic susceptibility patterns of the bacterial isolates showed that all the bacteria isolated were susceptible to Gentamicin (GEN), only Proteus vulgaris and Bacillus spp were susceptible to Ceftazidime (CAZ) and Cloxacillin (CXC) respectively and all the were resistant to Ampicillin (AMP). The presence of these microorganisms showed that snail's samples harbor some potential pathogenic bacteria of medical importance and washing with some cleansing additives, especially lime is recommended for proper decontamination. The resistance of the organisms to some of the drugs portrayed the global increased concern over the continuous use of antibiotics in human and veterinary medicine and the resultant effects.