study on microbial quality of livestock water source in the desert and semi-desert of naein rangelands (isfahan province – iran)

As various microbial pathogens could be transmitted to livestock from drinking water, detecting the bacterial content of water sources is important. coliforms are the most common microbial contamination of drinking water. their presence could indicate fecal contamination of water which accounts for severe waterborne fatal diseases. in this study, the bacterial quality of three water sources (spring, well, and qanat) in summer and winter was carried out by mpn (most probable number) in naein rangelands grazed by goats and sheep regularly.water samples were collected from 19 water sources (6 wells, 6 springs, 7 qanat) intended for feeding livestock in naein rangelands in the summer and winter of 2019. water sampling was done in a 250 ml glass container and kept refrigerated. the presumptive coliform test was performed by most probable number (mpn) and the number of coliforms in 100 ml was recorded and compared by the maximum tolerated level of total coliforms (500 coliforms/ml) the tds (total dissolved solids) recorded (mg/l) also.the result showed:1- the level of coliform contamination in qanat and well are higher than critical level.2- the mean of contamination in summer and winter are higher than critical level. 3- mpn and tds are negatively correlated (p<0.05).although the water samples contained coliforms that suggest livestock sewage, the mpn in spring was significantly below the critical level (500 coliform/100 ml).to prevent the hazard of microbial contamination, it is important to monitor water regularly and take the necessary action.