Abstract
A number of bacteria contaminating working boots used in a broiler farm was surveyed. The highest degree of bacterial contamination was obtained in the boots used for carrying out litter and droppings from the house after shipment of broilers. Bacteria detected from bottom, heel, toe and shank of the boots ranged from 101.5 to 106.1 per 1cm2. Lower degree of contamination of the boots was observed in the boots used for preparatory operations of housing and brooding of newly hatched chicks and the boots for daily management. The ranges of bacteria detected from the boots used for operations of the preparation and the management were from 101.5 to 106.1 and 102.0 to 106.0 per 1cm2. The number of bacteria detected from the boots used for the removing operation of wasted litter was significantly higher than those of the preparation and management operations. A degree of contamination with bacteria of bottom and heel was higher than those of toe and shank of the boots.
Upper thresholds of bacteria in each range mentioned above were 106.1, 106.2 and 106.0 per 1cm2, respectively. Though bcterial counts were reduced after washing, 103.3 to 105.1/cm2of bacteria were detected from bottom and heel of washed boots.
Ultra-violet ray with 250 to 260nm of wave length was radiated to bottom and heel of the boots after washing. The more amounts of ultra-violet ray radiated, the fewer number of bacteria were detected. The number of detectable bacteria were reduced fewer than 101.0/cm2 when amount of radiation of the ray was more 104.75J/m2.
