Abstract:
Milk is important as a valuable diet, but due to its nutritional value and perishable product
it serves as an ideal medium for growth of various microorganisms under suitable
conditions, hence it is a staple food in epidemiology linked to zoonotic pathogens. This
study was carried out in two districts in Tanga region (Northern Tanzania) to estimate
microbial load, isolate selected pathogens and establish their possible sources or entry
along the milk value chain. A total of 114 respondents were interviewed and subsequently
milk samples were aseptically collected for laboratory microbial analyses using the
standard ISO procedures for Food microbial analyses — Horizontal methods. The results
revealed poor practices and lack of formal training on milk hygiene among most of the
actors. More than 90% of all handled milk samples had Total plate count (TPC) above the
EAC maximum acceptable standard of 2.0x10 5 CFU/ml. The overall mean coliform plate
count (CPC) was 1.8x10 6 ± 6.2x10 6 CFU/ml, which indicated poor animal husbandry and
hygiene practices. The values of TPC and CPC between independent variables were not
statistically significant different (P > 0.05). In the samples, one contained CPS isolate
counting to 5.1x10 5 CFU/ml likely to cause staphylococcal poisoning. Isolated bacteria
were Escherichia coli, Staphylococcus aureus and Listeria spp. including Listeria
innocua, Listeria ivanovii and Listeria monocytogenes. Other microorganisms included
Klebsiella spp., Proteus spp., Staphylococcus spp., Enterococcus faecalis, Bacillus cereus
and Pseudomonas spp. In the identified pathogens, L. monocytogenes was most (42.1%)
predominant. The quality of milk was poor; unhygienic practices, poor animal husbandry
practices, organization of milk supply chains, dysfunction of the regulatory agencies and
quality control structures predispose the public to risk of contracting milk-borne
infections. Training on animal husbandry practices and public education on general milk
handling and hygiene are recommended. Also, sector policies, organizational structures
and support services and research into public health risks in milk must be focused.
