Evaluation of bacterial contaminants and heavy metals in cow and buffalo raw milk sold in Baghdad governorate

Abstract

The purpose of this study was to investigate bacterial contamination and heavy metal concentrations in 80 samples of raw milk (cow: 40 and buffalo: 40) gathered from local markets in Baghdad, Iraq. The culture results were classified into ten categories: E. coli was 100% in each cows and buffaloes, Enterobacter Spp 23.75% (25% cow, 22.5% buffalo), Pseudomonas Spp 13.75% (15% cow,12.5% buffalo), Klebsiella Spp 15% (17.5% cow, 12.5% buffalo), Staphylococcus aureus 12.5% (15% cow, 10% buffalo), Staph. epidermidis 5% (for each cow and buffalo), Proteus spp. 10% (12.5% cows, 7.5% buffaloes), E. coli O157 15% (25% cow, 5% buffalo), Yersinia enterocolitica 3.75% (5% cow, 2.5% buffalo) and Salmonella 13.75% (25% cow 2.5% buffalo). The averages of heavy metals concentrations in cow milk samples were 0.62±0.25, 0.25±0.22, 0.31±0.20 and 21±2 mg/kg and in buffalo milk samples were 0.60±0.3, 0.33±0.15, 0.27±0.11 and 18±2.5 mg/kg for Lead (Pb), Cadmium (Cd), Copper (Cu) and Nickel (Ni) respectively. The high concentrations of pathogenic bacteria and metals found in the milk products is a sign of inadequate hygiene and sanitation during milking and post-milking operations, as well as excessive levels of heavy metal pollution in the environment which will affect meat and milk produced by these animals.