Water quality at a crossroads
by Katie Savage (May 2007)
Putting a water trough in pasture keeps cows — and pathogens — out of nearby waterways
Water troughs are quenching cows' thirst and keeping them out of waterways.
Adding a water trough to a field can significantly decrease the amount of defecation in adjacent creeks and streams, according to a University of Guelph study. Cows given the alternate source drank from it 83 per cent of the time and spent less time in waterways.
This knowledge can help farmers reduce pathogens in nearby waterways without having to fence them off from pastures, says Paul Sharpe, an animal science professor at University of Guelph's Kemptville campus, who spearheaded the study. "Adding water troughs to pastures offers an option to improve water quality at a minimal expense."
Sharpe wants to identify management practices that help minimize pathogen levels in water. His two-part study aims to evaluate the environmental impact of cows crossing through and drinking from waterways by tracking changes in the number of water pathogens.
First, Sharpe and his research collaborators took water samples from the creek in the pasture passing through the Kemptville campus, before and after the water trough was offered. Early results showed that when cows had an alternate drinking source available, there were fewer pathogens present in the nearby water. Sharpe is currently assessing how temperature and rainfall affect pathogen levels in the creek.
In the study's second part, which began last year, Sharpe is evaluating the influence on pathogen loading of cows crossing through the creek. Animals are being grazed on one side of the creek, then crossed to the other side twice per day. The researchers take water samples before, during and after the cows cross through the creek to measure bacteria counts, pH and electrical conductivity. They're also counting the number of creek bottom-dwelling organisms to see how the crossings affect marine life.
Final results from both study parts are expected later this year. In the future, Sharpe plans to look at how shade availability and temperature influence the frequency of grazing animals going to water. By evaluating more variables in this experiment, he hopes to better understand cattle behaviour and determine why they use the creek. That, he says, will help farmers minimize the number of pathogens in their waterways.