It is a fact: water is an essential nutrient for the health and productivity of dairy cattle. Yet, the quality of the water consumed by dairy cows in Quebec had remained largely unexplored. A team of researchers, led by Véronique Ouellet, a professor and researcher at Université Laval, therefore set out to investigate the issue.
The researchers analyzed drinking water from 49 dairy farms located in various regions of Quebec, using samples collected in March and August. The results confirmed links between water quality, season, region, treatment system, and milk production.
Excessive mineral concentrations and impact on dairy cows
Véronique Ouellet and her research team examined the levels of about ten minerals. They noted excessive concentrations of iron, manganese, and phosphorus, particularly in the summer.
Iron and manganese, which are often found in groundwater or result from mining activities, give water a metallic taste, thereby reducing water consumption and potentially milk production.
Phosphorus, on the other hand, which comes from organic decomposition or industrial activities, can interfere with the absorption of other essential minerals such as calcium and magnesium. This imbalance can affect the fertility of cows.
Despite the presence of a water treatment system on 55% of farms, 63% of them had at least one water quality issue.
Beyond the water treatment system…
As the name suggests, a water treatment system is used to treat water in order to remove, in theory, microbes and minerals. In practice, this isn’t always the case…
To address high mineral concentrations, reliable results must first be obtained. To do this, the researcher emphasizes the importance of using an accredited chemical analysis laboratory.
Véronique Ouellet also notes that a treatment system represents a significant investment for growers, which is why it’s important to choose one based on the specific problem to be solved.
For example, UV lamps reduce microbial contamination but not mineral contamination. Thus, if the water has too high a concentration of manganese, iron, or phosphorus, a reverse osmosis system would be ideal.
“The effectiveness of treatment systems depends on the problem to be solved. It is necessary to precisely identify the problem before investing.”
Véronique Ouellet
A first step toward better equipping dairy farmers
This study lays the groundwork for a better understanding of water quality issues on Quebec dairy farms. It contributes to refining provincial guidelines for drinking water monitoring and to creating practical tools to support producers and agricultural advisors in their work.
The research findings also highlighted correlations between water quality, water treatment systems, different regions of Quebec, and animal production performance.
And this is just the beginning: the research team aims to go further to deepen our understanding of how water quality affects cow health and milk production. Nothing better than research findings to raise new questions!
Learn more
Check out the project sheet entitled From water trough to production: the importance of water for dairy cows to learn more about water quality on Quebec dairy farms (Véronique Ouellet, Édith Charbonneau, Débora Santschi).
And the article published in the magazine Le producteur de lait du Québec (July 2024) (French only):
