Easily overlooked, water could be regarded as the single most important nutrient in a dairy cow’s diet. Ruminant nutrition specialist and SealesWinslow’s Science Extension Officer, Natalie Hughes, shares her insights and outlines how you can influence animal health and productivity with water.
You might not think about water when you think about milk.
But milk actually contains about 85% water and this fundamental fact goes some way towards illustrating the link between water and milk production. “If water is restricted, milk production will suffer. It’s as simple as that,” says Natalie.
Water is an important nutritional factor and vital for daily functioning. The demand for it is driven by various factors including the milk production cycle, body size and daily activities such as walking to and from the shed. Temperature also plays a role (cows need more water on a hot summer’s day than cool, wet days), as does the water content of their feed or the dry matter percentage.
The cow’s stage in the lactation cycle is a major driver, remarks Natalie. “Generally speaking, a lactating cow requires around 70 litres of water per day, whereas 45 litres are sufficient for a dry cow. A good portion of that may come from pasture.”1
We humans avoid drinking water with slime or “floaties” in it and cows are no different! As Natalie puts it, “if you wouldn’t drink it, then don’t expect your cow to”. Her view reflects best practice, which recommends regular cleaning of water troughs, especially when minerals are added, as a build-up can easily taint the water flavour, making it less palatable. She advises, “Don’t stop adding minerals, but be wary of water quality.”
A visual assessment will often provide clues to water quality, e.g. discolouration may signal the unwelcome presence of heavy metals or high iron levels. This not only taints the water but can also have a detrimental effect on the cow’s metabolism if minerals are added to the water. High iron content, for instance, can inhibit the uptake of other minerals, specifically copper, zinc and selenium. Testing the water can show any unforeseen issues.
A drop in those minerals has wide-ranging adverse effects, such as reduced reproductive performance and poor immunity.
If there’s any doubt, a simple and affordable water test allows you to make appropriate adjustments.
Adding minerals to water is not only convenient, it’s highly effective.
“Remember that mineral demand also peaks with milk production,” says Natalie. “Adding minerals in the weeks before calving until the end of mating will assist in addressing any imbalances.” Inadequate intake can lead to reduced peak milk performance, poor conception rates and/or reduced post-peak production.
Choosing the right mineral blend can be tricky so Natalie suggests testing the pasture against diet requirements, taking water test outcomes into account. This establishes any mineral surplus or deficiencies and will reveal any minerals limiting uptake.
Natalie recommends SealesWinslow’s Micromax range. Its formulation is based on the results from thousands of local herbage tests and consequently reflects New Zealand conditions. There’s even a Micromax Plus range containing chelated copper, specifically for farms that struggle with high iron levels.
For more information on the SealesWinslow’s Micromax range talk to your local Fonterra Farm SourceTechnical Sales Rep or visit your Farm Source or RD1 store.
115 kg DM of average spring pasture at 25% dry matter content, for instance, contains 45 litres of water.
Article supplied by SealesWinslow