Weal's Robotic Milking System

May 2015

Gavin and Susan Weal have installed a robotic milking system on their Waikato dairy farm

In 2012 Gavin and Susan Weal downsized their dairy farm and started to design and build a new robotic dairy. The intention was to implement a system that gave them more flexibility and freed them from the twice daily drudgery of milking. It has worked, and they have shown that robotic milking is a good option for a relatively small, all-grass farming system. Production per cow has improved and they are very pleased with the more flexible lifestyle that the semi-automated regime has allowed them.

Gavin and Susan run a split spring/autumn herd of 182 dairy cows on 71 ha (65 ha effective) of flat to rolling land at Pokuru, near Te Awamutu. Gavin has lived all his life on the farm, which was previously 115ha before they decided to downsize in 2012. Gavin had milked cows for 40 years and was well and truly ‘over it’ and wanted to step back and let their son Stuart manage the property. However, the cowshed was on the 44 ha that they sold, so a new one was needed.

“Gavin started talking to the cowshed builder about a herringbone but he has always had a huge interest in robotic milking and the builder had just converted a shed to robotics. They went and had a look at it and Gavin decided that was what he wanted to do,” says Susan.

“Originally we were going to put in two robots but then we realised that three would be more efficient and it gave us more flexibility because we expected to build up to 200 cows quite easily. We started milking in the new shed in May 2013.”

Gavin designed the shed the way he wanted it, with easy cow flow being the most important feature. He had to incorporate a feed pad that was already in place as well as a three-race system, and place the robots so that when the cows were being milked they looked out at the races rather than at the office or interior of the shed. Susan says that the design works very well and is being copied by the Lely Company that supplied the robots.

“When the cows have finished milking they walk straight out into the exit yard and then on through the main drafting gate to one of the races. We have an ABC race system, meaning that every eight hours the cows exiting the shed will go to a different paddock. The drafting gate is fully computerised and will change races at 12 noon, 8pm and 4am,” she says.

“Our paddocks are actually quite small, just 0.8 hectares, and that works really well. Some people said robotic milking wouldn’t work with a fully grass-based system but it does, and the cows love it.”

The paddock rotation is normally straightforward with the feedpad incorporated for supplementary feeding in winter or a dry summer. Cows wander in for milking when they feel like it, an average of 2.2 times per day although that can vary from 1 to 3 times depending on the cow and her stage of lactation.

While being milked, each cow gets meal and molasses. The computer works out how much to give them based on their production and it feeds that amount over 24 hours. This provides an incentive for cows to come in for milking and was helpful in training cows to present themselves to the robots.

“It took about five days to train most cows to use the robot system; the worst ones took a couple of weeks. The system has saloon gates that allow only one-way traffic, and at first I wondered how we were going to teach them to go through all these gates but they are way more intelligent than you think, and they worked out the system pretty quickly,” says Susan.

“There is a saying that it takes two weeks to train the cows and two years to train the farmer and that’s probably quite right because it is quite weird to get your head around the fact that the cows control the system, you don’t. My son struggled with that at the start, he was the routine kid that got up, milked, shut the cows in, fed out and cleaned up and all of a sudden these cows were doing what they wanted and he was not quite ready for them to do that.”

However, once the system was up and running it allowed the Weal family much more flexibility. (The family includes two daughters; Rachel, who works as a farm line relationship manager with the ASB Bank, and Rebecca who is a 4th year veterinary science student). They were no longer tied to the shed and milking times and could choose what to do. An array of sensors linked to the computer meant that they could monitor what was happening 24/7 and receive alerts if anything went amiss.

“If a robot has an issue, for example if flies are bad or the cows may be moving around and kick off one of the cups and it gets hooked up behind another one, it will try milking three cows and if it fails because it can’t lift the cup up and put it on the teat, the computer rings you on the cell phone,” says Susan.

“And if for some reason one cow fails to be milked perhaps because one cup won’t fit on, then the machine will send her back around again up to 3 times and if it still fails, it will draft her out into the side yard and that will be noted on the computer so you can go and have a look to see if there is something wrong.”

“Initially we panicked a bit if the phone rang, especially if we were in town because there are quite a lot of reasons it could shut down, but now we are more relaxed about that and if we are away for an extra hour, it is not a big deal.”

So far there have been few times when an alarm has summoned them and then usually for minor problems, such as a cup getting tangled or the teat spray has run out. Any problem with power cuts is avoided by having a generator on standby that will fire up automatically if the power goes out.

The robotic milking system makes full use of other electronics that improve efficiency and decision making. Sensors record milk volume for each cow and monitor milk conductivity for each quarter as an early warning for mastitis. Looking at the conductivity history for each cow leads to better decisions about if and when to introduce control measures. If antibiotics need to be used the cow stays with the herd but the computer diverts her milk away from the vat and drafts her out once a day for treatment.

Movement sensors on each cow’s collar identify those that are on heat – tail paint is unnecessary – and the system drafts them out for AI. Susan says that it is surprisingly accurate and for each cow a heat graph is produced for staff to read and be alerted to look for mating behaviour.

The daily routine is not governed by the need to gather up the herd and milk them twice a day. Typically Gavin might head to the cowshed around 7.30am and check or treat any cows that have been drafted out. He also hoses down the yard with a steam cleaner, something he does several times each day. Then it’s a matter of checking that all stock are out of the night paddock and getting that race ready for the next round. The rest of the day is then available for routine or seasonal chores, and maybe the occasional day in town.

Time flexibility is one of the advantages of a robotic milking system. Another is the quiet and relaxed disposition of the cows, something that Susan says other people notice.

“The stock just take their time and come when they are ready, nobody is ever behind them on the bike hassling them. The pecking order has changed quite a bit too and there is less bullying,” says Susan.

“The cows don’t seem to be bothered by the heat; they just stay in the paddock and come to the shed when it’s a bit cooler. I was a bit worried that they might try to crowd into the shed for shade or shelter but that hasn’t happened.”

The easier pace of life has meant that stock health has improved. There are still a few lame cows during the season but nothing like when the herd was being milked conventionally. The vet seldom visits unless it is to vaccinate for leptospirosis or for an emergency.

Production per cow is up from 430kg MS in the herringbone shed to 508kg in the first season, and Susan says they are targeting 550kg this year, although the drop in projected payout has meant that it is not economic to feed as much meal and molasses as in the past season. The per cow increase may be partly because of a more conservative stocking rate but Susan believes it is also because the cows are being milked more frequently – they average 2.8 milkings per 24 hours in the peak of the season and 2.2 over the whole season.   Last season they produced 86,000 kg MS on 65 ha with 170 cows, which equates to 1320kg/ha and 505kg/cow.

The feeding regime is mainly pasture with home-grown grass silage and maize when the feed pad is being used.

So far the Weals have bought in replacement stock and additional cows, but they plan to rear their own replacements and choose bulls that will throw progeny suited to robotic milking – teat placement is one important trait to select for.

Susan says that the system nearly caused a divorce. Robots were $250,000 each and the full turnkey system including gates, races, electronics, effluent storage etc. cost about $1 million. This compares favourably with a semi-automated herringbone shed of appropriate capacity costing $7 – $800,000.

Despite the high cost, the Weals are very pleased with their choice and see it as a valid option for farmers in a similar situation to consider.

“A lot of farmers are sick of having hassles with staff and all the red tape involved, and for this size of farm it is a great option, especially for people like us who’ve had enough of milking but don’t want to get out of farming, because it eliminates quite a few problems and offers a better lifestyle,” says Susan.

“Yes, it is expensive but not too much more expensive than a conventional shed, and it is about choice. As I said to one person who asked me, it is not all about money, it is about something that you really want to do and have a go at. Gavin said he didn’t want to die wondering whether it would work or not, and he is delighted with how it has all gone. It is technology and it seems to be the way of the future.”