Dairy farming and the New Zealand environment

Public opinion of the perceived environmental damaged caused by dairying is not so positive; it’s a media and political hot potato. Expansion of intensive dairy production over the years has led to greater levels of nitrogen in soil, surface and groundwater. So what options are available to farmers to help reduce our footprint? 

Fewer cows

Its election year and The Labour Party have been kicking around the idea of reducing or at least capping cow numbers. As an industry, this is a warning call to heed; we need to take responsibility and make meaningful long-term changes to discourage politicians from thinking they need to step in.

Improve efficiency per cow

Reducing leaching per KG of milk solids is another option, either by getting more from the same number of cows or using less cows to produce the same amount. 

Different feeds

New Zealand pasture is an excellent source of feed but it is higher in protein than necessary. Using cheaper feeds such as grain and sugar beets, better balances the excessive protein in pasture, thus reducing the amount of nitrogen in the urine. 

Wintering cows

A large percentage of annual run-off and leaching occurs during autumn and winter so getting cows off the paddocks during these months is essential to reducing nitrogen levels. Dairy Barn Systems are an excellent way to achieve this. These environmentally friendly cow houses not only provide a contained effluent management system, they’re better for animal comfort and well being, and present an opportunity to work towards a 12 month milk production cycle.

Repurposing effluent

The most environmentally friendly systems are those that contain the effluent and recycle the nutrients to grow feed. A Stuff article from March 2017 features a Matamata farmer who operates a hybrid pasture/shed system. This farm captures all of the effluent from their 480-cow herd, which is then redistributed as fertiliser on their maize block, a crop that provides supplementary feed (about 40% of their diet).


Breeding to reduce nitrogen excreted in urine is one of the many research and development programmes conducted by CRV Ambreed aimed at improving farming sustainability using genetics. This year at National Fieldays they launched their LowN sire bulls.The offspring of LowN Sires™ have reduced MUN concentration; international research shows if MUN is reduced, the amount of Nitrogen excreted in urine is too. This is another potential solution for more sustainable dairy farming in New Zealand.

Tell the public about positive improvements

Perhaps what is most frustrating is that many farmers are making changes. But unless we make an effort to promote this fact, negative perceptions (false or otherwise) will prevail. Here’s a useful opinion piece on ways to avoid the backlash.

Make sure you know what to do

DairyNZ has a guide to good environmental management on dairy farms available as a free downloadable resource. The document describes what good environmental management looks like on a dairy farm.