The Havelock North water contamination in August last year threw water quality into the spotlight across Hawke's Bay, but particularly in the Tukituki River catchment.
Although the cause of the gastro outbreak was this year confirmed as being caused by sheep faeces from a neighbouring paddock entering a Brookvale Rd bore supplying Havelock North's water, the event put the focus on feedlots among other farming practices.
The Hawke's Bay Regional Council acknowledged the management of feedlots by many farmers in the region was not acceptable and must improve.
Some see feedlots as polluting, unhealthy, intensified operations that endanger water quality and New Zealand's clean green grass-fed image.
Others see them as highly-managed, secure production systems that comply with water quality standards and animal welfare codes, and offer economic growth opportunities for the region around them.
Central Hawke's Bay farmer Phil King, who has farmed his 340ha property on Tikokino Rd since 1973, has his gumboots firmly planted in the second camp.
There are three consented feedlots in Hawke's Bay and Mr King owns and operates one of the biggest, covering 45ha and consented to hold 4500 cattle at any one time.
The farm backs on to the Waipawa River and while 55 per cent of it sits on good alluvial soils, the balance is on gravel-based soils.
The gravel's thin layer of top soil was not productive, said Mr King.
"Over the years we had trouble in spring with the westerlies - 45 per cent would dry out within two to three weeks."
His traditional regime of running capital stock ewes and cattle became inefficient, so eight years ago he started a cropping operation growing barley, peas, sweetcorn and maize in summer, and oats and brassicas in winter for the feedlot or wintering cattle.
Then, about two and a half years ago he was approached by Australian livestock exporter Austrex to see if he would consider establishing a quarantine operation for heifers before they were sent overseas.
Not shy of innovation, Mr King took up the idea, and the first shipment of live cattle bound for Vietnam left his property in 2015.
A load of 3200 Angus cattle was sent to China in February last year, and he recently exported a line of cattle as part of a 4400-head shipment to China through Landmark, another Australian-based company.
Mr King said he contributed about 1600 cattle to that contingent.
As well as quarantining, he has run winter programmes, including growing bulls one year and heifers in 2016.
The aim of a feedlot is to feed animals well so they grow at maximum rates, and to finish them within 60 to 70 days.
To achieve this the conditions must be favourable to the animals, and as efficient as possible, he said.
At his property, the feedlot is split up into 1ha paddocks each containing a water trough.
The animals are fed a diet of maize silage, maize grain and kibbled barley, which is overseen by a professional nutritionist.
With their food needs taken care of, the cattle are docile and thrive, Mr King said.
"The cattle we had on here a month ago were probably the best fed cattle in Hawke's Bay - they sit around the feedlot, food is available to them all the time.
"We are feeding them to maintain health and grow them a little bit."
Often when export cattle arrive they can be tired, they may have done a long journey, but within a week they are thriving and their coats are glossy, he said.
For dairy export shipment, in particular, the diet was not to grow them fast, rather feeding them to improve health and maintain or slightly improve body weight.
"If you feed them too well they get too heavy for the boat."
Mr King is consented to run his operation and said that was a priority from day one.
"I got a consent straight away because this is a significant operation - we can run 4500 cattle here, the maximum we've had is 3400."
Part of the consenting process required installing three monitoring bores, which were professionally tested by the Hawke's Bay Regional Council once a month.
Mr King said throughout this testing he had complied with the consent conditions, and the water quality had not changed in the past two years.
"The water level under the monitoring bore is 7.5m to 8m below the surface - the water quality has not changed because feedlotting is about controlling what the animal eats.
"It's a controlled protein and starch diet - if you feed the optimum level of protein at 15 per cent there will be no surplus nitrates coming out the back of the animal as it is using up all the protein."
The solid waste of the animals was fibrous and inoffensive, immediately breaking down to compost, he said.
"By controlling what goes in the front end you are controlling what comes out the back end."
With pastoral farming, it could not be controlled in the same way, but all farmers were aware of their environmental requirements and were doing their best to achieve the standards continually being put on them, said Mr King.
"It has to be monitored, we are all accountable.
"Farmers have been described as greedy, self-serving, environmental vandals.
"But, farmers are making every effort to comply with the bar that's been continually raised to meet the public's expectations - they are willing to do this at significant cost."
