Water Quality for Calves

Water is an essential nutrient. In importance to sustaining life and optimizing growth, it is second only to oxygen. Emphasis is often put on offering clean water early, and in adequate amounts to young calves. Water is important for metabolism, digestion, rumen development, excretion of waste products, and transport of nutrients throughout the body. 

Although the emphasis is there to offer water, and to keep clean water in front of the calf, the quality of the water available is often overlooked.

Factors to considered in a water quality evaluation include:

Odor and Taste

When calves detect an unpleasant odor or taste, they will be less likely to consume adequate amounts of water. Being that we are humans, it is difficult to determine exactly what the calf considers to be offensive in smell and taste. We do know that most causes of offensive odor and taste are a result of substances present in excess, and/or the presence of bacteria and their metabolic byproducts. A water quality analysis could help to determine why the water might not smell or taste good to the calf.

Physiochemical Properties

Physiochemical properties of water include pH, total dissolved solids (TDS), water hardness, or other substances in excess.

Ideally water pH should fall between 6.0-8.5. Water with a pH less than 5.1 may increase problems related to chronic or mild acidosis, while water over a pH of 9.0 may contribute to chronic or mild alkalosis. 

TDS is a sum of all the inorganic contaminates in water. Levels of 1,000-3,000 mb/l TDS are ideal for drinking water. Levels > 3,000 mg/L are more likely to cause poor tasting water, and result in decreased intakes. All water testing >1,000 mg/L TDS has the potential to cause problems and it would be a good idea to further test if for all major water minerals, salts, and metals.

Water hardness is mostly a measure of calcium and magnesium in the water.  Hard water generally does not adversely affect the animal. Extremely high concentrations of calcium or magnesium above 500 mg/L should be included in ration formulation.

Presence of toxic compounds

Nitrates can occur in both feedstuffs as well as water. Drinking water concentrations >20 mg/L as nitrate-nitrogen could present health issues.  

Coliform bacteria live in all surface waters and in many groundwater wells.  Coliform bacteria in wells usually come from a surface water source or from insects under the well cap. The concentration of coliform bacteria is strongly related to the location where the water sample was taken. Water samples from drinking troughs or buckets may have large concentrations of coliform bacteria especially if they are cleaned infrequently. Clean and sanitize drinking troughs, buckets, and tanks daily to reduce bacteria loads. E. coli bacteria occur from direct contamination from fecal waste. The occurrence of E. coli bacteria is much more serious than total coliform bacterial contamination. Frequently clean water locations to minimize exposure of E. coli or other fecal bacteria contamination. The goal is for the water analysis to not show any E. coli or fecal coliform bacteria present.

Micro and Macro Mineral Concentrations

Sodium in well water is not usually a problem for cattle. However, sodium concentrations over 20 ppm should be included in ration formulation. Water that has run through a water softener can have very high concentrations of sodium and should not be used to mix milk replacer or be used as drinking water unless it has been tested and verified to have levels of sodium less than 100 ppm.

Iron and Manganese are very common pollutants in groundwater.  Iron levels > 0.3 mg/L and Manganese levels >0.05 mg/L may cause offensive taste.

Chlorides >250 mg/L can cause water to taste salty and may result in lower intakes. High chlorides should be considered in ration formulation as excessive chloride may be detrimental to rumen function.

High sulfate levels in water may increase the animals needs for selenium, vitamin E, and copper. Ideally concentrations of sulfate will be <500 mg/L.

Copper levels may be elevated from corrosion of metal plumbing components, mining, or from treatment of ponds with copper sulfate algaecides. Copper levels > 1.0 mg/L may cause a metallic tase and reduce water intake. High copper concentrations may also cause liver damage.

Other minerals, heavy metals, and toxic compounds may also be tested for to identify cause of any problems that may occur.

There is a lot more to water quality than just keeping the trough clean. Ideally wells should be tested at least once per year for pH, total coliform bacteria, nitrates, and TDS. Elevated levels of any of these components would call for further testing. 

Written by: Mariah Gull, M.S.