Q: Why is water quality a concern at this particular point in time?

GEIGER: At this point, we are dealing with two things, the onset of winter and very wet conditions in the fall. This fall presents a challenge because very wet conditions can drastically change the water composition at a given location due to runoff of soil, contamination etc. Due to this increase in water that is coming into our water sources, we have to test our water to make sure we are not seeing an increase in less desirable (antagonistic) molecules. Regularly, we recommend testing water every six months (spring and fall are best) to help deal with the variability that is associated with the season. Ultimately, we cannot fix what we do not know is present.

Q: What challenges do you see arising among dairy cows and young stock right now due to issues with water quality?

GEIGER: Ultimately, it comes down to water either not being available or containing higher levels than we would like of antagonists. Both of these result in decreased water intake, which will impact health and performance. High levels of antagonists also can impact the nutrients the animal gets from her diet. (see Figure 1.) For example, iron is antagonistic to zinc, manganese and copper absorption. Antagonism is really an element (iron in this example), tying up another molecule, such as zinc. Thus, an animal may then exhibit symptoms of a zinc deficiency, even when the diets appear to be well-fortified on paper.

That said, the diet we put in front of the cow may not be utilized well due to what is in the water. For example, high iron in the water can tie up many trace minerals. The issue is, there are many things that are regional to certain areas of the U.S. For example, I was dealing with some very unique heavy metals when I lived in western Ohio that are not common in many other places. These issues can worsen during times of high rainfall. That is why we need to test our water. See desired levels for various compounds in Table 1.

Q: How can dairy producers be better prepared to deal with water quality challenges right now?

GEIGER: Once again, we need to regularly test our water. We cannot help what we cannot see. If we are dealing with issues and they are reoccurring on a given farm, there are water treatments. Installing these types of technologies, if necessary, can help us get ahead of future issues.

Q: When it comes to water testing, how often should it be done, and what are a few key points of how to interpret test results?

GEIGER: I want to see this done at least twice each year. Here are some pointers for testing water:

• Use sterile, plastic bottles supplied by testing laboratory
• Return water samples to lab within 24 hours of collecting
• Sample the same water source from which animals drink
• Collect water from stream running from waterspout, not directly from trough or pool of water
• Collect samples from more than one barn and more than one location to get representative sample
• Let the water run for several minutes from each source before collecting the sample
• A basic initial water analysis is typically:

1. Total dissolved solids (TDS), pH and hardness
2.  Excess minerals or compounds (sulfates, chlorine, iron, manganese, nitrates – see Table 2)
3. Coliforms and bacterial counts (see Table 3)
4. Toxic compounds (heavy metals, organophosphates, PCBs and hydrocarbons)

Table 4 shows some basic things to look for in terms of interpretation. The interpretation impacts the solution.