Aad and Wilma van Leeuwen say the barn runs like clockwork. John Bisset/Fairfax Media
The quiet comes as surprise. No stomping or scraping of hooves, no mooing or snorting as one might expect from 1150 dairy cows housed under one roof. Instead, it’s the subdued munch of animals feeding and the soft clunk and hum of the robotics that make this, the world’s largest dairy barn, operational.
It belongs to Aad and Wilma van Leeuwen of van Leeuwen Dairy Group, one of the biggest dairy collectives in Canterbury. The company comprises 12 holdings and 12,000 dairy cattle.
Three of the farms are run by Aad and Wilma’s children. The giant barn, which was completed last September, is the third “robotic” dairy barn the van Leeuwens have built, but the first of its scale. Behind the drive to build it was the premium price paid for winter milking, a shortage of skilled staff, and the challenge.
“Winter milking in this part of the world is tough on cows and staff,” Aad said. “In a nutshell, robotic, or voluntary, milking systems (VMS) allow dairy cows to live indoors and be milked without human labour. The core of the system is a type of agricultural robot, and computers and special herd management software.”
The van Leeuwens said they saw a challenging opportunity when a 600-hectare property at Makikihi came up for sale. There was ample potential – enough land to build a barn and grow the feed to sustain it.
An external view of the 13,000 sq m barn. It is the size of two rugby fields. John Bisset/Fairfax Media
However, the land was within Environment Canterbury’s orange (at risk) and red (unacceptable) water quality zones. They needed to prove the farm would be run “sustainably” using only the effluent from the barn as fertiliser.
“On this farm, what comes out of the barn is recycled and goes back on to the farm,” Wilma said. “We’ve proved to the authorities that what we are doing here is sustainable. The farm grows all its own cow fodder on surrounding land (apart from meal pellets fed during milking) and so completes the cycle of a completely self-sufficient farm.”
It took 12 months to build the 13,000 square metre barn (193m x 67m) and install the 24 DeLaval robots needed for the milking. DeLaval is a Swedish company that develops, manufactures and distributes equipment for milk production and animal husbandry.
A view from the “bridge” showing five of the 24 milking machines. John Bisset/Fairfax Media
The cows were introduced in September last year: 740 to begin with; currently 1150, but increasing to a full capacity of 1500 within the next few months.
First up, the cows are trained to voluntarily enter the milking stall and be milked. Lured in by a tasty snack of meal pellets, they are milked by robots with hydraulic arms guided by optical cameras and dual lasers. Each teat is cleaned with warm water and air, stimulated, pre-milked before milking, and disinfected after milking.
Each robot is controlled by a touch screen, with the capability of remote operation from the central office, suspended below the ceiling with a birds-eye view of the barn. Special collars and ear tags collect data on the cow’s yield, how many times a day she has milked, and her general health. If she has milked recently, the robot turns her away.
A cow takes advantage of the automated back-scratcher. John Bisset/Fairfax Media
The 24 milking robots are arranged in eight groups with 60-65 cows milked per robot. After milking, the cows either go back to the barn or are sorted into a separation pen for treatment or insemination if required.
In the meantime the milk is piped to two silo tanks outside the barn, from where it is collected by tanker. On its way to the tanks it is cooled using a pre-cooler, and then a water chiller.
The water used for pre-cooling is later given to the cows and the heat-recovery system takes care of the warm water needed to clean the milking robot. Cleaning of the robots is done via a cascade system, so that in each group there is always at least one robot available to milk the cows.
Hundreds of cows feed contentedly in the van Leeuwen’s giant dairy barn. John Bisset/Fairfax Media
The effluent is removed regularly by scrapers, and collected in a 12.5million litre above-ground tank outside the barn. Later it is spread by vacuum tank onto the surrounding pasture. The tank is sufficient to store half a year’s worth.
The vast barn will house the cows for 10 months of the year. The cows are rotated outside for the two months they aren’t lactating. The floor is rubberised for their comfort, and each animal has an individual stall with foam mat to lie on, and the use of a back-scratcher.
There are multiple feed lanes distributing a mix of maize silage, lucerne silage, grass silage and protein additives. Cows can feed, wander along the lanes, lie down or be milked at will and appear tranquil and relaxed.
By end of the year, the Van Leeuwens will introduce a new technology called the DeLaval herd navigator to test milk for signs of ketosis, mastitis and whether the cow is in heat.
“The navigator can identify cows in heat with 95 per cent accuracy,” Aad said. “It will detect 80 per cent of mastitis (an infection of the cow’s udder) before it becomes visible.”
When the barn reaches full capacity (1500 cows) it is expected to produce a massive 1.2million kilograms of milk solids a year. (Milk solids are the protein and fat left after water has been removed from the milk). Already the cows are producing twice the milk they would if outdoors. The van Leeuwens want to push production up to 700-800 kg of milk solids per cow within three to five years.
“The cost of production is just over $4.50 a kg of milk solids,” Wilma said. “The home-grown fodder – mainly maize, lucerne and grass silage – was costed at 20 cents a kg of dry matter for budgeting purposes, but we can produce it for less.
“We sold a 450,000kg milk solids farm and invested its proceeds into this farm, which is going to do nearly three times the production by the time it is up and running fully.”
“It gives you a bit of an idea with what you can do, compared with outdoors.”
The van Leeuwens feel robotic milking gives farmers the chance to reduce labour costs per kilogram of milk solids produced. It also does away with the need to milk twice a day. As well as increased production, it offers a better lifestyle for the farmer, their staff and the cows,
“These are happy cows and happy cows produce more milk,” Wilma said.
Source: Stuff