EVALUATION OF THE HYGIENIC QUALITY OF RAW MILK BASED ON THE PRESENCE OF BIFIDOBACTERIA SPP. AS AN INDICATOR OF FAECAL CONTAMINATION IN ASSIUT CITY

Marwa M.n El-Gendi ,Lamiaa M.t Ali

doi:10.21608/avmj.2012.173814

Abstract

This study aimed to evaluate the hygienic quality of raw buffalo's and cow's milk sold in Assiut city, Egypt; based on the presence of Bifidobacterium spp. as indicator of fecal contamination. Bifidobacteria species forms one of the most important groups of flora in the intestine of both human and animals. Speciesisolated in humans are different from those isolated in animals. It should therefore be possible to determine contamination origin (human or animal). Seventy samples of raw buffalo's and cow's milk (35 samples from each) were collected randomly from; some dairy farms, individual cases of dairy buffaloes and cows and dairy shops in Assiut city, all samples were examined for the presence of Bifidobacteria spp. Each sample was firstly inoculated in MRS & BHIMup, then two different culture media (CMup & Bifidobacterium media (BFM)) were used for isolation and identification of Bifidobacterium. Bifidobacterium spp. was identified in 65.71 % (23samples) and 51.42% (18 samples) of raw buffalo's and cow's milk, respectively. Isolates were identified and differentiated and the findings revealed that raw cow's milk harboured B. dentium in 61.11% , B. suis in 27.77% and B. bifidum in only 2 samples (11, 11 %) of examined samples. B. dentium, B. suis and B. bifidumwere found contaminating 47.82, 39.13 and 13.04 % of examined raw buffalo's milk samples. Presence of B. bifidum revealed contamination of raw cow's and buffalo's milk with human stool (adult and infants); however isolates of B. suis indicated the contamination with feces of piglets. Also the detection of B. dentium in examined samples showed that there is contamination with human discharges coming from mouth suffering dental caries; human abscesses, vaginal discharges and feces. These organisms considered potentially pathogenic and have hazards effect on human health.

Highlights

The local dairy commodity chain, from farm to retail sites is informal and often escapes monitoring of quality
Present study has been carried out to evaluate the hygienic quality of raw buffalo's and cow's milk sold in Assiut city based on the presence of Bifidobacterium spp. as indicators of faecal contamination
Isolates were identified and findings revealed that raw cow's milk samples harbored B.dentium in 61.11% while B. suis was identified in 27.77% of examined samples(Table, 2)

Summary

Introduction

The local dairy commodity chain, from farm to retail sites is informal and often escapes monitoring of quality. Most stakeholders lack knowledge on hygiene and sanitary aspects of their production, which can result in poor production standards and contamination of local raw milk. Bifidobacteria are well known for their beneficial effects on health and are used as probiotics in certain food and pharmaceutical products. Since they constitute one of the most important bacteria group in human and animal digestive tract, they were recently considered as fecal contamination indicators in raw milk dairy products. Fecal contamination of raw milk in farms has been shown by the detection of the same and most frequent Bifidobacterium spp. in milk as in cow's dung. The standard in Europe for fecal contamination control of raw milk cheese is Escherichia coli (Beerens et al, 2000)

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Conclusion