Some of the technology, which has moved from the realms of science fiction farming to reality was unveiled to delegates at this year’s New Zealand Grassland Association conference in Tauranga.
The conference looked at nitrogen measurement and mitigation, reflecting increased pressure to understand how to control nutrient losses to protect the environment while maintaining profitability.
AgResearch scientist Keith Betteridge outlined how GPS tracking, movement monitors and urine sensors have been used on trial cattle in Taupo, providing an insight to high-risk nitrogen loss from urine deposits.
He has developed three-dimensional graphics showing where the deposits are occurring, ranked by intensity.
Flatter regions in hill country are preferred sites for cattle, in contrast to sheep.
Some cattle camp areas have recorded nitrogen losses as intense as 950 kilograms a hectare.
Mapping deposit intensity would enable farmers to determine where to put nitrogen inhibitors should an alternative evolve to DCD, which was banned last year, Betteridge said.
“We have also found there is a huge range of nitrogen concentration per deposit. It is highly variable, as is the volume of deposit.”
This was in contrast to the accepted lore that every urine patch amounted to a deposit of 800kg of nitrogen a hectare, he said.
The sophisticated sensors attached to trial cattle were capable of measuring the volume and nitrogen concentration of urine.
The work also provided valuable data on timing of deposits and offered insights to the value of grazing cattle on pasture, then removing them to a feed pad to capture the bulk of urine deposits post-grazing.
Betteridge said it was critical to understand cattle nitrogen losses better because they deposited twice the rate of sheep or deer.
A solution to the problem was presented to delegates by electro-mechanical engineer Geoff Bates.
Bates has teamed with fertiliser pioneer Dr Bert Quin in the Pastoral Robotics company to develop robotic means of getting nitrogen inhibitors on paddock after cows have left.
Quin had been trialing tail-mounted delivery systems for dairy cattle but was enticed to robotic delivery because of advances in technology, including battery power improvements.
“We have also found there is a huge range of nitrogen concentration per deposit. It is highly variable, as is the volume of deposit.”
Keith Betteridge
AgResearch
“There are a number of reasons for wanting to apply effluent the way we do,” Bates said.
“One is time. Farmers are time-limited at a period when it needs to be applied the most.”
The prototype robot, Mini-ME, works on GPS guidance, using technology that can sense urine patches and apply an inhibitor to the patches.
Pastoral Robotics intends to release its “beta” version of the robot at next year’s Mystery Creek Fieldays.
Bates said while DCD had been dropped as an inhibitor after the food scare last year, there were other inhibitors available and up for consideration. However, details of particular inhibitors remained a trade secret.
“What the robots can do is map the farm ground and cover the areas where nitrogen from urine is most likely to be. As Keith Betteridge’s research has shown, that is usually on the flatter areas where the machine can go.”
Ultimately the technology could be used to apply specific amounts of fertiliser to specific parts of the paddock, he said.
“We can see it ensuring less fertiliser use, less leaching and more grass.”
