Machines and equipment for automatic cattle feeding
The unifeed technique, which was developed experimentally in the 1950s and later established in the 1960s, involves the preparation and administration of a homogeneous and balanced mixture of all the components of the daily ration in a single distribution. It immediately proved to be a viable method of feeding ruminants, so much so that it soon became the solution adopted in almost all intensive and semi-intensive cattle farms. The "unifeed" production implies the availability of a prominent level of farm mechanization, in which the mixer wagon represents the main and indispensable machine. However, its very widespread use and many years of use have highlighted some of its limitations. Perhaps the most important is the variability in the composition of the ration, including the moisture content of the various ingredients, which means that the distribution at the trough may be qualitatively different from that planned by the feeder. Another variable to be taken into account is the work required to return the feed to the trough as often as possible due to the sorting that the animals do in favor of the more palatable components (the so-called "feed sorting"). In addition, the time required to prepare the ratio, the need for high specialization of the personnel in charge of operating the chopper-mixer and its high cost can make this operation quite costly and delicate for the production process.
Today, innovative technologies, namely dedicated sensors, automatic pushers and Automatic Feeding Systems (AFS), are available on the market. These systems can provide concrete support to farmers in ration preparation and distribution and feeder management, reducing possible limiting aspects as much as possible.
NIR sensors and optical sensors to be applied to the mixer wagon allow, respectively, to precisely control the amount of feed loaded based on its chemical characteristics and assess the homogeneity of the ration and fiber length to define the correct mixing time.
Automatic pushersautomate the process of bringing the product closer to the trough, freeing the farmer from this tedious and repetitive activity while improving the feeding of the animals. The animals always have a well-matched ratio available throughout the day, placed at an optimal distance from the rack.
AFS systems represent the most complex and innovative technology in livestock farming: available in distinct types and levels of technological complexity, they are easily adaptable to any livestock farm and farm structure. There are currently more than 20 AFS manufacturers on the market, with more than 1,300 systems installed worldwide; the reasons for this success can be justified by the significant reduction in the time needed to prepare and distribute rations and the ability to calibrate a balanced, high-quality ration. In addition, ratios can be fed more frequently than once or twice a day, ensuring that animals receive fresh food at all times. By increasing the number of feedings over 24 hours, the number of visits to the feeder also increases, which results in longer feeding times and higher dry matter intake, with positive effects on cow health and production.
Automatic pushers. After feed distribution, feeder management is another crucial factor in keeping the ratio as palatable as possible throughout the day, reducing feed sorting and bringing feed close to the rack so that it is always accessible to the animals. The frequency with which the fodder is brought closer together is crucial in order to improve the dry matter intake rate of the animals: this operation, carried out periodically by the farmer by hand or with the help of small self-propelled vehicles, is fully automated thanks to fodder pushers, which allow up to 10-12 approximations in 24 hours, of course, able to operate at night when farm operators are not present.
The most widely used automatic feed pushers are small autonomous robots that approach the feed by means of a rotating drum or auger. They use either special magnetic sensors embedded in the barn floor or optical sensors that follow the barn wall so that they can be conveniently oriented along the path to be taken.
Automated Feeding Systems. However, the highest level of automation for ration preparation and feeding is represented by automatic feeding systems (AFS). There is a very wide range on the market, allowing the farmer to choose from a large number of types and models that best suit the characteristics of the farm (structure, size, housing, etc.). Each AFS generally consists of three areas: the raw material storage area (also called the "kitchen"), the preparation area and the distribution area, some of which may be combined into a single unit.
The Kitchen and Preparation Area. The kitchen is a room that is always covered, sometimes with movable walls, located directly in the barn or, more often, in a self-contained outdoor building, usually adjacent to the barn. All the ingredients that make up the ration are stored here, bearing in mind that, at least in Italy, concentrates can be stored in silos in considerable quantities and hay in heaps, while silage cannot be piled up in copious quantities to avoid fermentation. The main equipment inside the kitchen room, depending on the type of AFS, are overhead crane with a self-loading crane, inclined hopper for unloading products by gravity and horizontal hopper with a loading belt, mixer and distribution wagon, or just a chopper-mixer if this option is available.
The Distribution System. Distribution systems can be divided into two macro-categories: Stationary: basically, based on the use of conveyor belts; Mobile: include rail suspended or guided or even self-propelled type of wagons.
Mobile suspended wagons can operate in two modes: distribution of a ration already mixed in the kitchen or direct mixing and distribution of ingredients taken individually from the kitchen itself. They are characterized by wagons of limited capacity (1 to 3 m3) that move along the feeder development suspended on a rail that defines their direction and provides the energy for movement.
Guided wagons are usually only available in the mixer-distributor version and have a rail installed along the feed alley or directly above the rack. Contrary to the previous solution, the wagon is equipped with steerable rubber wheels. This allows not only directionality but also the weight of the equipment to be discharged to the ground, thus avoiding burdening the barn structure.
Self-propelled wagons are available in 3 versions of increasing complexity (distributor only, mixer-distributor, chopper-mixer-distributor). They are battery-powered robotic systems equipped with steerable rubber wheels characterized by limited capacity wagons (up to 4 m3), which move around the barn by means of special magnetic or optical sensors both along the feeder and service paths.
Concluding considerations. From the point of view of farm management, the adoption of an AFS not only results in more visits of animals to the trough but also affects the organization of activities, combining the reduction of labor requirements with the improvement of the quality of work compared to the usual technique based on the use of self-propelled or towed chopping-mixing wagons. In fact, several studies have shown a 50-60% reduction in the time needed to prepare the ration by switching from a conventional system consisting of a chopping and mixing wagon coupled to a tractor to an AFS.
The energy aspect is also not insignificant: the use of an AFS, driven entirely by electric motors, can lead to lower energy costs for ration preparation and feeding.
During the AUTOFEED Project, funded by the Lombardy Region under the 2014-2020 RDP and coordinated by the CREA in Treviglio (https://autofeed.crea.gov.it/), a reduction of between 80 and 90 percent of the energy required for ration preparation was observed by switching from conventional yards driven by endothermic engines to AFSs with kitchen and self-propelled chopper-mixer-distributor robots driven by electric motors. It follows that, in addition to the operational advantages already described, from an economic and environmental sustainability perspective, the greater efficiency found in ration preparation using AFS can lead to lower energy consumption, lower production costs and reduced environmental impact, aspects that are more relevant (and obviously virtuous) than ever for sound farm management.
