Dry feeding and liquid feeding in pig rearing
Housing and feed are important elements during weaning, but feeding young piglets requires specific pig feeding systems and management strategies. Modern feeding systems have shown to support the pig farmer to better control post weaning stress and loss in daily gain.
Trends in pig production
In recent years a number of trends have been established in pig rearing which also have an influence on the design of feeding techniques and the management of feeding. Among others, these include:
- the weaning of piglets in groups, resulting in larger groups of animals,
- the placement of the piglets in separate pig houses, spatially separated from the sows,
- compartmentalized arrangement of the pens, and
- increased requirements on pig feeding systems
A consistently high animal performance is only possible when the technology and the management are optimally adapted to the different growing periods of the piglets, thus permitting the farm manager to quickly react to any situation.
Three main phases in pig rearing
In pig rearing, there are three main phases, which are repeatedly emphasised in specialist literature:
- the first ten days after weaning,
- day 11 after weaning until the weight is approximately 16 kg, and
- from 16 kg onwards until the end of the rearing phase, around 28 to 30 kg live weight
The first couple of days after weaning represent the most critical phase for the piglets. Priority is given to the piglets‘ adjustment from the highly digestible, natural sow milk to artificially-produced animal feed. In addition, the piglets have to adjust to their new surroundings and to unfamiliar group members. As, at this time, the digestive and immune system of the piglets are not fully built up yet, there is a high risk of diarrhoeal diseases. A preventative measure against diarrhoea is to frequently feed only small portions of easily digestible nutrients. In addition, the piglets should become accustomed to the new feed as quickly as possible, however, in order to minimize the inevitable “growth break” after weaning this should only happen gradually.
Liquid feeding in pig rearing – optimal feed consistency
To support a gradual transition liquid feeding system should be considered as this system delivers liquid to porridge-like feed with a consistency which is optimal for the nutritional requirements of piglets.
In this context, special sensor-controlled liquid feeding systems for piglets are becoming more and more important. In such pig feeding systems, the individual feed portions are transported to the trough by means of compressed air which also ensures that the feed pipes are left completely empty after feeding so that there are no residues. These systems provide a very good feeding hygiene in pig production and allow the farm manager to ideally adapt the feed recipe and temperature to the requirements of the piglets.
Liquid feeding routine in pig production
In order to support the adaptation to the new situation (different pig house, different pig house environment, larger groups, different feed) it is necessary to establish a synchronous feeding routine appropriate to the generic feeding behaviour of piglets. This is ideally attainable with an animal to trough space ratio of 1:1. The feed amount can thus quickly be increased, until approximately 10 days later, when ad libitum feeding is reached. The supply of warm feed has proved itself because it is much better accepted by the piglets. The feed is tastier and easier to digest, especially by the more sensitive piglets. Moreover, due to the higher temperature, it can be utilised and converted into growth much better.
In the ad libitum phase, the feed intake is increased by more frequently dosed small portions of fresh feed. However, the feeding place hygiene also plays and important role in pig rearing! Feeding breaks during the natural quiet times at midday and at night ensure that the feed troughs are getting emptied completely.
Advantage of block liquid feeding
From a weight of approximately 16 kg, the piglets enter a phase where they must share thefeeding area with other piglets. For the piglets this means ranking fights and therefore an increased level of stress. As soon as the social structure of the piglets has been developed, the order for feed intake is set according to rank. The higher-ranking piglets eat first, and the lower-ranking ones afterwards.
From feeding perspective, this phase should be accompanied by an ad libitum block feeding procedure. This means that piglets receive their full ration during several feeding blocks per day. Within a feeding block, a staggered delivery of food also gives the lower-ranked piglets the possibility take in sufficient feed. With the classic ad libitum feeding, the lower-ranked piglets can begin with their feed intake after the higher-ranked piglets have eaten their fill.
Hygiene status in the pig house
The hygiene status in the entire pig house – particularly the feed and water supply – is of the highest importance. Exposure to germs of any kind must be absolutely avoided and monitored in regular intervals! The entire feed supply chain, from the storage of the raw components to the preparation of the feed mixture, from the transport routes to the pig feeding system, must be closely observed! If too little attention is paid to hygiene in liquid feeding systems, the feed lines might develop bio films which act as a nutritional solution for the growth of different bacteria. The quality of the water, which is one of the most important components in pig rearing, should be checked regularly! Unfortunately, this is seldom the case.
Dry feeding in pig rearing – simple and hygienic
In many operations today, rearing piglets are fed dry feed. In particular, the simple dry feeding technology and the hygienically favourable supply of feed are named as advantages. The feed supply and the pig feeding system itself are easy to manage.
In the classic dry feeding situation, the feed is supplied to the piglets from the start ad libitum and dry. The piglets have to insalivate the feed a lot more so that the feed intake takes much longer than with porridge-like or liquid feed. It is important to make sure that there is a sufficient intake of water via easily accessible drinkers, since piglets repeatedly switch between the feeder and the drinker while eating. If it is not possible for the piglets to take in sufficient water, the feed intake might decrease. In order to lower the risk of diarrhoea, many farms work with additional feeding places (e.g hand-feeding bowls) in the first few days. This is done to facilitate the transition from the rationed milk intake at the sow to ad libitum feeding at the pig feeder.
Technological requirements in regard to dry feeding
Over the last couple of years, with regard to dry feeding, technological requirements concerning animal performance and health have continuously increased. Feed consistency in the trough, feed composition, animal / feeding place ratio and frequency of feeding are the most important parameters which receive more and more attention.
Pig feeders for wet/dry feed
Pig feeders for wet/dry feed have established themselves as a better alternative to the classic dry feeding. Thanks to drinkers inside the trough, the piglets can themselves mix the dry feed into a mash. This porridge-like feed is much better accepted by the piglets so that the daily feed intake is higher than with pure dry feed. Different studies were able to prove that the daily intake can thus be increased. Pig feeders for wet/dry feed do require slightly more management as the settings on the metering system must be frequently checked. The settings should be such, that the piglets cannot dampen too much feed at once, which will then not be entirely eaten.
Frequent, small feed rations can reduce the risk of diarrhoeal diseases as an overfilling of the gastro-intestinal tract is thus prevented. Thanks to modern, computer-controlled pig feeding systems, this feeding strategy can also be realized with a dry feeding system.
Feed quality in a dry feeding system
In a dry feeding system the quality of the feed is also very important. In addition to tastiness, feed structure and nutrient composition, the silo hygiene, as in liquid feeding, play an important role in this context.
From a technological point of view, two computer-controlled dry feeding systems have to be distinguished – depending on whether the feed is measured into the individual valves based on volume or based on weight.
Volume-based and weight-based feed measuring pig feeding systems
A volume-based feed measuring pig feeding system requires no mixer as the feed is mixed directly in the conveying tube. The extraction hopper beneath each silo contains a frequency-controlled auger which measures the individual components into the conveying tube as required. Inside the tube, the components are mixed to form the desired recipe which is then delivered to the valves. Such a volume-based feed measuring system is simple and economic. There is no need for a separate distribution unit and feed kitchen. The individual ingredients only have to be measured in litres.
A computer-controlled dry feeding system with weight-based feed measuring operates with a weighed mixer. It is thus possible to produce an individual feed recipe for every valve with a very good mixing quality and mixing precision. It is furthermore possible to establish phase feeding at every valve or upgrade the system to sensor-controlled feeding. In this case, every feed hopper contains a sensor which sends a message to the computer when the hopper is empty at the start of the feeding cycle.
Liquid feeding / dry feeding in pig production
Each of the before mentioned systems can support piglet growth; however, the conditions on a farm, individual requirements of the producer, as well as the specific feed components are decisive factors of whether a liquid feeding or dry feeding system is to be installed. The main key to success is a pig feeding system which is carefully adapted to the respective farm.
By Dr. Anne Elkmann and Norbert Bärlein, Big Dutchman
This article was published in Pig Progress Piglet Feeding Special 2011 (Vol. 27)