5 Factors to Optimize Milk Production with Water Quality
Every dairyman knows that good quality feed is key to good cow health and production. But, how often do you look at the quality of water you provide your cows?
A lactating dairy cow has one of the largest water requirements of any animal.
The average cow uses 1,000 litres of water to produce just 1 kg of milk. To replace this water a cow spends 12-15 minutes everyday drinking almost 100 litres of water. In hot weather, this intake can reach as high as 150 litres a day.
Cows need water for a number of functions. Sufficient amounts of good quality water are essential for digestion, metabolism, waste elimination, respiration, heat exchange, nutrient transport, and electrolyte balance. A pregnant cow has higher water requirements for maintenance because she also has to maintain the fluid environment for the fetus.
Cows drink about 60 to 80% of the water they need. The rest comes from moisture in feed and metabolic processes. A cow’s diet, milk production, and environmental factors all influence how much water she needs.
If your cows aren’t drinking enough, you could see decreased immune function (high SCC), fertility problems, and off feed/erratic eating patterns.
The quality of water that’s available to your cows is also important to how much they drink. You might have water quality problems if you see a decline in health and performance, digestive upsets, and deteriorating health of new arrivals. Of course, an off flavor, smell, or color of water is also a tell-tale sign of poor quality.
Problems affecting your cow’s water can be grouped into different factors. Sensory qualities, physical and chemical properties, mineral content, presence of toxic compounds, and microbial contamination can all contribute to poor water quality.
Elements, Minerals and other Compounds
A number of substances in water can cause undesirable tastes, odors, and appearance to drinking water, as well as health problems in some cases. In general, mineral content- measured as “total dissolved solids (TDS)”- content higher than 3000 mg/L is very unpalatable.
The TDS measures the total inorganic matter dissolved in the water, so water with a high TDS test could be due to a single substance at extremely high levels in the water, or multiple substances that are only moderately elevated.
Some bacteria are highly attracted to iron, causing slime which can give water an unpleasant appearance and texture. It is best to keep the iron content of water below 0.3 ppm, especially if sulfate levels are also high. Manganese is another element found in water that can also cause slime to form at high levels.
Hydrogen sulfide levels over 0.1 ppm cause a distinctive rotten egg smell that can make cows avoid drinking. More than 250 mg/L of chloride gives water a salty taste. Copper can enter a water source through corroding pipes or other areas of the environment, and levels above 1mg/L in water can cause a metallic taste.
Effect on Health
Mineral content is also known as total dissolved solids (TDS), total soluble salts (TSS), or salinity. It indicates the total amount of inorganic matter dissolved in the water.
Water with a mineral content less than 3,000 ppm can cause mild diarrhea. Levels between 3,000 and 5,000 ppm occasionally cause lower yields during the summer months. Mineral content higher than 7,000 ppm is considered unacceptable for dairy cattle.
Excessive iron intake produces Reactive Oxygen Species, which can cause oxidative stress and result in decreased immune function leading to diseases like Mastitis and Retained Fetal Membranes. Although high manganese levels are not associated with health problems, it is poorly absorbed by the body so a maximum content of 0.05 ppm in water is recommended. In addition to reducing palatability, high levels of copper can also cause liver damage in cattle.
Sulfur and sulfate compounds in water can also affect dairy cows. High concentrations can have a laxative effect if cows are not able to adjust, with under 500 ppm considered safe for calves and under 1000 ppm safe for adult cattle. Levels high than 3,500 ppm can lead to significantly reduced feed and water intake. The health effects are also dependent on whether the calcium, iron, magnesium, or sodium form of the compound is present. High sulfate is linked to reduced milk fat and increased selenium, vitamin E and copper requirements.
Physical and Chemical Properties
Water hardness can contribute to palatability, as well as the flow of water. Hard water can cause mineral deposits in pipes and other equipment, restricting the flow of water to the trough. The main contributors of water hardness are calcium and magnesium, but zinc, iron, strontium, aluminum, and manganese may also play a small part.
Acidity is also important. Although there is no official guideline for the pH of drinking water for dairy cows, 6.0-8.5 is usually considered acceptable for humans. A pH less than 5.1 risks acidosis, and over 9.0 risks alkalosis.
There are several substances in water sources that can be toxic to cows, either discouraging them from drinking, or causing them poor health if exposed to toxins at low levels for a long time. Hydrogen sulfide is rarely found in water sources but when it is found, it is toxic.
Luckily detection is easy due to its characteristic smell.
Water sources are more commonly contaminated by nitrates, especially surface or shallow ground water. Safe levels for dairy cows are considered to be under 10ppm for nitrate-nitrogen compounds, or under 44 ppm for pure nitrate compounds. Long-term exposure to moderately high levels of nitrates can reduce fertility. Nitrate poisoning occurs when high levels are converted to nitrite by bacteria in the rumen. Nitrite is absorbed into the bloodstream and reduces the ability of oxygen to be transported throughout the body.
Poor water quality due to bacteria can cause dairy cows to become ill, or at minimum reduce their water intake. A microbe count higher than 1 per 100mL causes scours in calves. In adult cattle, a count higher than 15-20 per 100mL causes diarrhea and reduced feed intake. As mentioned earlier, compounds such as iron and manganese can act as a food source for certain types of bacteria.
How can you Improve Your Dairy Water Management?
Your water quality matters when it comes to your cows’ health and milk production. Poor water quality causes health problems, can discourage cows from drinking, and impacts milk production. To make sure that your cows are receiving the best quality water, tests should be done at least 4 times a year to collect seasonal data.
At the end of the day, good health and milk production starts with what goes into your cows, including the quality of your water.
Are you looking for ways to increase your dairy milk production? Our milk quality solution can help you to increase your production and revenue. Find out how by visiting our milk quality control solution page, or contacting us at 1-855-232-4797.
About the Author
Anna Schwanke is an undergraduate student at the University of Guelph, Ontario. She is responsible for researching and writing about a wide variety of topics related to dairy cow welfare and management for Dairy Quality Inc. The 10 years she spent living in Australia, as well as her love of travelling, give her a firsthand viewpoint of issues facing the international dairy community. She plans to graduate from the University’s College of Physical & Engineering Science in 2019 and pursue a career in the Life Sciences or Agriculture industry.
You might also enjoy: