Водные патогены присутствуют в сточных водах крупного молочного завода летом и зимой

Аннотация

Dairy wastewater is a valuable resource in semi-arid regions that can be recycled, therefore it’s potential content of epizootic pathogens, endotoxins and other hazardous substances is very timely and important. Bacterial and fungal epizootic pathogens were studied in wastewater on a 4,500 cow dairy in the Southern High Plains, U.S.A.. The wastewater was collected in triplicate from 13 different collection points along the wastewater drainage system, starting in the milking parlor and ending in a lagoon; and from an irrigation center pivot that applied the lagoon wastewater mixed with fresh water to forage crops, later used as feed for dairy cows. Pathogens were found at all collections points, except two points where chlorination was used. Eight Salmonella serovars were identified; most wastewater samples contained Escherichia coll O157:H7; and Listeria monocytogenes was found in mean concentrations from 1 x 104 to 1 x 105 CFU/ml. The mean concentrations of Staphylococcus spp, (1 x 104 to 1 x 107CFU/ml) and Enterococcus spp (1 x 104 to 10 x105 CFU/ml) were also high. The mean concentration of mesophilic fungi ranged from 1 x 102 to 1 x 105 CFU/ml. The center pivot wastewater contained fewer of each pathogen studied, and no Enterococcus spp were identified from this site. One of the most biologically active substances found in the lagoon wastewater was endotoxin which had a mean concentration of 37,712 EU/ml. These data show dairy wastewater can be a significant source of epizootic pathogens and endotoxin.