Water: the often forgotten nutrient

With temperatures starting to consistently drop below freezing it is important to make sure the water sources in your barn are in proper working order and not frozen. Water is essential for milk production, growth, and health, while also being needed for proper rumen function, nutrient digestion and absorption.

This is especially true when for every pound of milk a cow produces, five pounds of water are needed. Additionally, cows drink 30 to 50% of daily water intake within an hour after milking. Ensuring water flow rate of 2 gallons/minute for every cow that drinks at one time is needed to ensure adequate water intake.

Concerned about low water intake? What to look for

Knowing whether your cows are drinking enough is critical and intake differs with age and lactation. There are several possible causes of low water intake and signs can include:

• Firm, constipated manure

• Low urine output

• High packed-cell volume or hematocrit in blood

• Considerable drops in milk production

• Drinking of urine or pooled water

Reasons for low water intake can range from a lack of waterers to a lack of water supply to potential contaminants in the water. Taking a systematic approach to determine the reason behind limited water intake is beneficial and should start with evaluating the waterer. Determine water pressure to ensure it is at least 20 pounds to allow for multiple cows to drink simultaneously in a short time period. Also look for corroded valves, clogged pipes, and buildup of slime or scale. Check for stray voltage around the drinking device and around the surface that animals stand on to access water. Ensure waterers are 6 to 12 inches deep, have enough space for several animals to drink at once, and have a 2 inch space for every cow drinking around the perimeter. Consider social behaviors and the influence they have on a subordinate cow’s willingness to approach a waterer if a dominant cow is present. Although providing one waterer per 30 cow corresponds with recommendations, ensuring there is a secondary waterer within a pen will allow for reduced competition and social stress.

Are you waterers clean?

Maintaining waterer cleanliness is quintessential to stimulating water intake. Algae is a common problem in most waterers. It is important to keep algae levels to a minimum as there are at least 6 types of algae that can be toxic to cattle. Waterers can be treated with 35% hydrogen peroxide (8 ounces per 1000 gallons of water) to eliminate unwanted algae populations. Slow release chlorine tablets though effective, pose other concerns for their use on farms. Using chlorine to treat water is an effective way to remove dissolved iron, magnesium and hydrogen sulfide; however, chlorine concentrations over 1000 ppm can result in milk fat depression and reduced water intake. Alternative methods should be used for routine waterer cleaning.

Have your water tested

Finally, consider having the water supply to your dairy tested. Iron greater than 3000 ppm in the drinking water of your cows can cause a number of problems due to its toxicity as well as further reducing water intake due to unpalatable taste. If the total dissolved solids concentration is greater than 500 ppm, high levels of sulfate and chloride are of concern. Sulfate and chloride are biologically active anions than can negatively affect digestion, electrolyte balance, and lactation performance if over supplied. If sulfate and chloride are at a level greater than 1000 ppm water intake is decreased. Treatment systems may be necessary to reduce the sulfate and chloride concentrations of your water.

by — Heather Tucker, The Miner Institute