Abstract:
Background: Raw milk is a natural product of mammals used as food by human beings that does not
undergo heat treatment. It may contain pathogenic microorganism which can seriously affect the
health of individuals.
Objective: To determine the microbial quality of raw cow milk and associated factors along the dairy
value chain in Jimma zone, Southwest, Ethiopia, 2018.
Method: A cross-sectional study design was employed from April to May 2018. A total of 150 milk
samples and 300 environmental samples were collected randomly from dairy farms, milk distribution
centers and milk retailer outlets found in selected district towns and town administrations of Jimma
zone. The total mesophilic aerobic bacteria, E. coli O157:H7, total and fecal coliform bacteria were
analyzed. One representative milk handler from each milk production stages was interviewed to assess
the knowledge, attitude and practice of milk handlers by using pretested structured questionnaire.
Descriptive statistics and multiple linear regression model were used to analyze the data.
Result: the mean total mesophilic aerobic bacterial count at dairy farm, milk distribution centers and
milk retailer outlets were 4.96±0.59, 6.29±0.19 and 7.25±0.14 log CFU/ml respectively. There was
statistically significant difference (p<0.05) among the milk mean total mesophilic aerobic bacterial
count along the supply chain and their respective mean coliform bacteria were 3.49±1.71, 3.75±2.74
and 6.85± 0.30 log CFU/ml respectively. There was statistically significant difference (p<0.05) among
the milk coliform count of raw milk along the supply chain. The mean fecal coliform count of water
sample in dairy farms, milk distribution centers and milk retailer outlets were 4.04±0.34, 3.72±0.53
and 2.20±0.51 log CFU/ml respectively. The mean coliform count of milk contact surfaces at dairy
farm, milk distribution centers and milk retailer outlets were 4.61±0.38, 4.71±0.52 and 4.75±0.51 log
CFU/cm 2 respectively. The overall mean score of knowledge, attitude and practice of milk handlers
were 62.44%±11.53, 57.98%±9.22 and 57.42%± 10.78 respectively.
Conclusion and recommendation: Milk quality in terms of microbial counts seems to be significantly
decreased after sending off by farmers. About one third of the analyzed samples classified as
unacceptable microbial quality. Educational status and attitude of milk handlers and the quality of
water used to wash milk contact surfaces and hands of milk handlers were the major factors affecting
the microbial quality of raw cow milk in the study area. Hence, measures should be taken to enhance
the knowledge and attitude of milk handlers and to improve the quality of water used in the milk
processing to prevent consumers from milk borne illness
