A couple tablespoons of bleach and stainless steel water troughs could be your next arsenal in the fight against Johne's disease. That's the conclusion from Kim Cook, a USDA Agricultural Research Service microbiologist at the agency's Animal Waste Management Research Unit in Bowling Green, Ky.

Thinking that water troughs could be an excellent home for bacteria, Cook compared the bacteria load in the slimy layers in water on the sides of the most commonly used troughs: concrete, plastic, stainless steel, and galvanized steel.

Three days after inoculating the water with bacteria, high concentrations of the bacteria were on all troughs, and they survived 149 days. But, the bacterial survival rate was lowest on the stainless steel. When three tablespoons of chlorine bleach was added per 100 gallons of trough weekly, she found that, by the end of the third week, less than 1 percent of the bacteria remained on stainless and galvanized steel troughs. When compared to other troughs, 20 percent remained on plastic and 34 percent remained on concrete. While stainless steel toughs can be expensive, it is estimated that a herd of 1,000 cows can lose as much as $200,000 each year due to the drop in milk production and culling as a result of Johne's infections.