High-Tech stabling: robots in animal husbandry
An increasing range of electronic technology and robots are getting to work in animal husbandry, from measuring out food rations to milking and other basic functions in stabling where intelligent systems can now carry out tasks and monitor environmental parameters, especially with a view to improved livestock health.
Joseph Engelberger, who built the first industrial robot in the United States, used to quip that he couldn’t say what a robot was, but could recognise one when he saw it. The same is increasingly true on the farm, where you may find a small robotic device keeping barn floors clean as well as large robot milkers. Both machines need no touch from human hand and reduce manpower needs, ensure improved health and safety for farm workers and their herds, and more time to improve animal well-being. Some recent innovations are described below.
Scientific Feed Management
Automation is widely applied in milking and feed management, even if Italian farmers find it hard to keep up with the cutting-edge and automatic systems are less widely used than they could be.
Fractional feed distribution’s advantages are well known. In cows, pH level is kept constant and peaks are avoided with a reduction in acidity and improved milk production. The optimum is a ration supplied 5-6 times a day, although this is out of the question with current technology.
The approach is handled by AFS, or an Automatic Feeding System by which the preparation and distribution of feed is automatized. An AFS plant has a warehouse for storing feed ingredients, mixing plant and distribution devices. Only one of these three phases may be automated because of lack of funding and/or the farm’s or the stable’s organisation and structure.
The market offers various devices, but they are all either fixed or mobile. A fixed unified mixer is fed automatically by conveyer belts or augurs controlled by a central computer. The operator simply has to monitor whether the conveyor belts are adequately supplied, also taking account of the fact that they may have a high capacity sufficient to cover supplies for a number of days. A set of load measurement cells are located under the mixer’s main hopper to monitor continuously the quantity of each ingredient added to the ration. The computer compares the data to its memorised recipe and activates the conveyor belts so as to keep the two in line. After loading and mixing, the feed is dispatched by conveyor belt to feed wagons for distribution to the mangers. The transporter may be aerial or ground based, using rails to follow a memorised route or guided by sensors sunk into the floor. Unloading is typically by conveyor belt. Power is almost always electrical, supplied by a battery pack recharged automatically when not needed. An aerial delivery system requires careful route design; especially to avoid creating difficulties for the normal equipment working on the farm, perhaps by ensuring the rails is high enough off the ground.
Mobile mixers are much more complex, but they are adaptable to stables of all kinds and herds of varying composition. The basic setup consists of one or more small mixers with hoppers of 2-3 m3 filled in a special area often called the kitchen. Loading devices are always automatic, whether sharp-edged buckets or conveyor belts. Fixed plants are easy to automate for only part of the process; for example, mixer filling could be manual. But mobile mixers need full automation because they have to deliver a large number of mixers a day.
In this case too aerial delivery systems are available, but wheeled robots are more common. They follow a pre-determined route, distributing the rations and also using deflectors to push residual rations from previous deliveries closer to the manger. Safety sensors enable the machine to avoid obstacles or stop it when a person or an animal enters its operating range.
High-Tech Milking
Milking is surely one of the most critical aspects of milk production. Trained staff willing to handle the physical, chemical and biological risks 365 days a year and twice a day are difficult, which is one of the major reasons why robot milkers have been one of the main automated additions to the stable. Originally designed for herds of around 50 head, they are now spreading to larger herds, also thanks to the significant economic advantages. In Europe, many farms have over four robots in each stable, and some over 40.
An AMS or Automatic Milking System has one or more milking positions with robot arms to attach and detach the milking heads to the udders, a control computer and a series of additional devices to wash and disinfect the udder and the milking head. The machine can also eliminate automatically the first milk jets and, if need be, sort out milk coming from cows undergoing antibiotic treatment, which is unsuitable for sale. The most complicated piece of engineering is certainly the milking arm and its connected device for correctly locating the udder in space. Various methods are used: infrared, high frequency sound, lasers or TV cameras, to get a 3-D view. A single arm may also serve number of milking positions, reducing the robot’s total cost.
One clear advantage of the whole system is that the number of milkings per day can be increased, leading to a quantitative and qualitative improvement in production, especially robot milking is integrated with automated feeding to distribute feed in smaller quantities throughout the day.
Robot milking also means moving and guiding the flock automatically, as well as identifying the animals with suspect health conditions and separating them from the others. Recent robot models can in fact use milk’s conductivity or the presence of high levels of somatic cells in the milk to identify possible infections.
In these cases, the machine automatically separates out the milk from the animals in question to avoid spoiling the whole day’s output. The most advanced milkers can also analyse milk samples to determine progesterone levels and give earlier warning of when an animal will go on heat. Another possibility is to analyse urea in the milk to establish whether there is the right ratio of energy to nitrogen and to correct the feed mix if need be. These analyses are not made on all milk samples. Rather, the robot looks up each cow’s identification code on a database to check which need an analysis and to send a sample to the analyser if an analysis is required.
A new frontier in robot milking is the introduction of automation to existing stables. For this, the rotating type is best. In this case, a number of robots do the job, some preparing the udder and nipple, others attaching the milker. There is no difference from a traditional robot, but productivity is greater (500-700 cows an hour in a 24-place milking shed) with a significantly reduced investment.
Useful, Small Robots
Because they cost less, smaller robots are certainly more widely used. Automating floor cleaning and pushing material such as feed where you want it involves essentially the same robot, to push feed to the manger or manure to the disposal channel.
For the latter case, a 300-400 kg steerable, battery-powered vehicle has a blade moved at 0.3-0.5 km/h. The robot is told which route to follow and when at the re-charging terminal. When the task is complete, the robot returns to the terminal awaiting new instructions. The vehicle is usually low so that it can move under gates and fencing and does not get in the way of the animals. Sensors, usually ultra-sound based, stop the device on contact with an animal.
Very similar designs are used for machines to push feed closer to the manger. Cows in fact pick out the best parts of the feed they are given, and in doing so push the rest away from the manger. The robot pushes the residue back with ineating distance.
