Proactive Management of Urinary Nitrogen

The Principle - No ruminating animal can store Nitrogen

Ruminant Nitrogen Utilisation Efficiency (RNUE)

Through greater understanding farmers can adjust practices to increase profitability and decrease environmental impacts.
What we have developed is a pragmatic method that has the ability to create win-win outcomes. Increasing Nitrogen efficiency will not only have an effect on profitability, the environment also wins.
Management of the Nitrogen and Carbon cycles defines sustainable agriculture but it cannot be achieved at the expense of profitability. Your animals are innocent participants, it is management that dictates the outcomes.
Proactive management.
By testing your feeds (pasture, crops etc), then running the figures through the programme, we can predict the potential urinary N/milk urea N of your animals. This means before your animals even enter the paddock you will know what urinary Nitrogen they will produce. This gives you the knowledge to actively manage your animals' performance, efficiency, urinary Nitrogen and milk urea Nitrogen.

By using the Nitrogen Utilisation tool, we can offer a pragmatic measure for farmers to assess how they can moderate N losses.

These two results are actual pasture tests taken and sent to Qlabs by farmers to evaluate their Ruminant Nitrogen Utilisation Efficiency (RNUE).

Both farmers were managing their farms under what they considered to be current day best practice, but the difference in outcomes is significant.

From these results we can see that cows fed on pasture sample name - Ryegrass will produce over twice  as  much  urinary Nitrogen  (374g/day more)  than   cows   grazing  on   pasture  sample name - J West.

Below is an example of the difference in outcomes for the cows grazing these two pastures:-

                                                       Mr A Farmer                                                                                
                                                           J West                                                                                         
                                                 Urinary Nitrogen                                                                            
                or 79.1g/cow/day above optimum                                          
                         79.1kg/100 cows for 10 days                                                      
0.791 tonnes of Urinary Nitrogen will be produced over and above optimum for a 1,000 cow herd over a 10 day period grazing on this pasture .                                                                               

Mr A Farmer


Urinary Nitrogen


or 453.1g/cow/day above optimum


453.1kg/100 cows for 10 days

4.531 tonnes of Urinary Nitrogen will be produced over and above optimum for a 1,000 cow herd over a 10 day period grazing on this pasture.

If you look at these results on a total catchment basis where tens of thousands of animals are grazing, the Ruminant Nitrogen Utilisation Efficiency (RNUE) Report will allow farmers to understand and act to produce greater efficiencies and sustainable outcomes.  The potential for this science to work with agriculture to mitigate environmental impacts is enormous.

Rnue Test includes: -

DM, Crude Protein, Total Carbohydrates, Fat, Ash, TDN, Crude Fibre, NDF, MJ/ME


It's as simple as taking a herbage sample, sending it to Qlabs by courier and we'll do the rest.


Arming yourself with the knowledge of what your animals are about to eat is a very exciting extension to help you make proactive decisions. Pasture composition varies throughout the year, for this reason, we have kept the cost as low as possible to allow you to build a library of pasture and feed results. As farmers you will know what variations of pasture occur at different times of the year, for example- autumn saved winter grazed pastures, full flush spring pasture, summer pastures, and so forth.

If you have wondered why animals change performance as feed types change, then test it do not guess it. The answers will put more money in your pocket.

Testing of silage, hay, crops, etc. will help you to match the right supplement with the right pasture profile. This will increase your animals efficiency and put more money in your pocket.