After air, water is the most important nutrient for livestock, but water quantity and quality are often overlooked on many livestock operations. Providing safe, clean water is critical to maximizing a cow’s milk production and cow reproduction performance. Cows need clean water for normal digestion, proper flow of feed through the intestinal tract, proper nutrient absorption, normal blood volume and tissue requirements.
Water Quality By the Numbers
Cows consume 30 to 50 gallons (115 to 190 liters) of water per day despite spending just 20 to 30 minutes per day drinking it. Water accounts for 87 percent of the milk a dairy cow produces. Drinking water provides 60 to 80 percent of dry and lactating cows’ water needs, while feed provides most of the remaining water needs.
Common Signs of Poor Water Quality
Poor quality drinking water can result in decreased milk production and cow reproduction failure. Some of the common signs of poor water quality in cows include:
- Depressed immune function and elevated somatic cell count, which can lead to reduced milk production and quality
- Increased cow reproduction failure, including conception failure, early embryonic death and abortions
- Increased off-feed events and erratic eating patterns
- Health or performance issues
- Scours or digestive upsets in replacement animals
- Deteriorating health status of newly arrived heifers or dry cows
- Off flavor, smell or color of drinking water
Calves Need High Quality Drinking Water Too
When considering water quality needs, many people consider the needs of a cow that is producing milk or reproducing, but calves need access to quality drinking water just as much. The quality of water used to make milk replacer is critical to a calf’s health, and the availability of fresh water also affects nutrient intake and the calf’s growth.
According to research by Dr. Donna M. Amaral-Phillips from the University of Kentucky, calves should be offered free-choice water along with calf starter feed beginning at 4 days of age. The research suggests that depriving calves of fresh water decreases starter intake by 31 percent and decreases weight gain by 38 percent. Calves fed free-choice water also had a lower incidence of scours.
Some of the signs of poor water quality in dairy calves are similar to those found in mature cows:
- Increased incidence of scours and digestive upsets
- Decreased immune competence
- Depressed daily gain and feed efficiency
- Increased off-feed events and erratic eating behavior
Water Quantity and Availability is Equally Important as Quality
Cows spend up to four to five hours per day eating, but only 20 to 30 minutes per day drinking water, making availability and easy access to clean, safe water a critical factor in meeting a cow’s hydration needs. A cow depends on readily-available water to maintain blood volume, tissue function, rumen activity and proper flow of feed through the digestive tract.
To optimize dairy cows’ water consumption, you should provide direct access to clean water as cows exit the milking parlor and within 50 feet (15 meters) of the feed bunk. There should be at least two functioning waters available per pen.
Some additional ways to optimize dairy cows’ water consumption include the following:
- Ensure adequate flow rate to maintain a minimum water depth of 3 inches (7.6 centimeters) in the trough
- Provide available trough space of 3.5 linear inches (9 linear centimeters) per cow
- Monitor stray voltage in water troughs and in the areas around them
Testing Drinking Water for Quality
Dairy producers should be testing their cows’ drinking water twice per year in the late summer and in the winter. Listed below is what producers should be testing for when testing water:
- Total dissolved solids, pH and hardness
- Excess minerals or compounds such as sulfate, chloride, iron, manganese and nitrates
- Coliform and bacterial counts
- Toxic compounds, including heavy metals, organophosphates, PCBs and hydrocarbons
Testing for dissolved solids is the first thing that should be evaluated and will reveal the sum of all dissolved and suspended inorganic matter present in the water sample. High concentrations of sulfate, chloride, iron, manganese and nitrates are known to significantly affect animal performance.
In addition, testing water for iron is critical because it is estimated to have a 100 percent absorption rate. If the iron level in drinking water is greater than 0.3 ppm, it may cause problems for cows, including decreased palatability and increased oxidative stress, contributing to immune dysfunction. This can lead to mastitis and metritis, or decreased absorption of copper, manganese and zinc from the cows’ diet.
Water contaminated with coliform bacteria can be detrimental to both humans and livestock while nitrates and nitrites can cause reproductive failure, depressed growth in young animals and can result in poor oxygen-carrying capacity of the blood. Generally, sulfates have a laxative effect on livestock, which reduces feed efficiency and performance. Sulfur and sulfates can also affect copper and selenium absorption rates, creating a need for adjustments in supplemental levels.
Zinpro’s H20 Water Analysis Program Helps Assess Water Quality
The Zinpro H20 Water Analysis Program is a step-by-step tool that puts livestock and poultry producers on the road to optimal water quality. The program analyzes and then compares water samples to water quality standards. The results can help nutritionists, producers and veterinarians identify areas of concern and review signs of potential toxicosis.
Getting the Best Results
A water test is only as good as the sample provided and the laboratory that conducts the test. When selecting a lab, choose one with experience testing water for livestock and dairy operations to ensure valid results. Below are additional steps for ensuring you get the most accurate results from your water test:
- Use sterile, plastic bottles supplied by the testing laboratory
- Return water samples to the lab within 24 hours of collection
- Sample from the same water source the cows drink from
- Collect samples from the stream running into the watering trough, not directly from the pool of water
- Collect water samples from more than one pen, barn or water trough, in more than one location
- Let water run for several minutes before beginning to collect the sample
Once the analysis is complete, dairy producers can start to make decisions about correcting water quality problems. Common water treatments, depending on the problem, include disinfection, water softening, iron filtration and reverse osmosis.
The Zinpro H20 Water Analysis Program recommends a follow-up analysis if the water contains any elements that approach or exceed the desired limits for livestock. Research shows that Zinpro Performance Minerals® are more metabolically available to animals in the presence of mineral antagonists in the water than other forms of trace minerals.
For more information about the benefits of receiving a comprehensive water evaluation using the Zinpro H20 Water Analysis Program or about including Zinpro Performance Minerals as a part of your livestock nutrition program, contact a Zinpro representative today.