The present invention relates to an installation for more humane, production stimulating and labour saving breeding of pigs.

It is probably commonly known today that modern farming is a capital intensive activity. The increasing demands on profitability in this connection, with accompanying rational use of machines and installations within the farming sector, have led to some recognized conditions within e.g. breeding of animals. During farrowing it is common that the sow is kept detained, fixed in position in the farrowing stall during the next few days after the farrowing, while in other systems she is kept fixed in position up to the point where the piglets are weaned at an age of approx. 6 weeks. The advantages that possibly are achievable with these systems, are probably in the first place a more rational feeding, and a relatively simple cleaning of the stables. However, a forced fixation of the sow on a very limited floor space, leads to her becoming very disturbed with a tendency to tread on and by mistake kill some of the piglets e.g. at times of feeding, since the piglets often reside in close proximity to the sow.

Another factor of importance is of course that the instinctive behaviour of the sow is inhibited in such an environment, where she is not able to move freely. Studies of pigs leading a wild life have shown that a sow that recently has farrowed has a very outspoken behaviour when feeding and taking care of the piglets, and when giving off excrements and urine. In addition, the sow has very determined locations where these activities are carried out. There are many indications that the normal behaviour of the sow more or less is inhibited in present systems for breeding.

Thus it would be desirable with freer breeding systems, where the pigs have a possibility to behave in a "natural" way, regarding the elementary life functions, such as feeding,

care-taking of the piglets and giving off the excrements.

The object of the present invention is thus to provide an installation of this kind, eliminating the drawbacks connected with previously known installations.

This object is achieved with an installation comprising a number of stalls placed in rows for sows and piglets, having a manure passage on one side and a feeding passage on the other side of the rows of boxes, and/or a particular feeding location for breeding-stock, located at a distance from the stalls. This installation is characterized in that each stall is provided with a gate that is swingable between a first position in which it bars the stall, and a second position in which it bars the manure passage, said gate being provided with at least one swingable shutter adapted to give the sow access to the stall, and a possibility to leave the stall, also at times when the gate is closed, said gate at the same time stopping the piglet from leaving the box.

The invention will be described in detail below in conjunction with the appended drawings. In the drawings

Fig. 1 shows a schematic view of an installation for production of pigs in accordance with the invention, and

Fig. 2 shows one embodiment of the gate, characteristic of the installation.

In Fig. 1 is disclosed very schematically an installation for production of pigs, comprising a row of stalls l,2...n for sows and piglets. In this embodiment each stall is provided with a swingable gate 3 as a protective means for the piglets. This gate 3 can be swung sideways from the position shown with a continous line to the position shown with a broken line, whereby the sow, when the gate is in the second position, has access to considerably more space. In the corner of the stall, at a distance above the floor a heating lamp 4 is suspended,

below which the piglets may lie. To the left of the stalls, e.g. at their head end, there is an inspection or feeding passage 5. In this passage at each stall there may be provided feeding troughs 6. To the right of the stall there is a manure passage 7. In the figure the characteristic gate 8 of the installation is shown in a position where it bars the manure passage. This gate is lockable in two positions, on one hand in the position shown with a continous line, and on the other hand in the position shown with a broken line. In the second line the manure passage is free to be cleaned with some suitable method, e.g. with a miniature tractor, or simply by hand with a rake. However, the sow has free access to the manure passage through the shutters provided in the gate (see Fig. 2), by virtue of the characteristic construction according to the invention.

The gate 8 shown in Fig. 2 is based on a conventional gate for installations for production of pigs. However, the gate according to the present invention is provided with at least one, and in the shown embodiment, with two self-closing swingable shutters 9, 10, one of which opens outwardly towards the manure passage, and the other of which opens only inwardly towards the pig stall. These shutters are so constructed that the sow can easily open them with her snout and walk out and into the pig stall as she desires. The shutter/shutters are located at such a height that the piglets only with very great difficulty, or even not at all, can climb or jump over the so formed threshold and pass through the shutters. However, they are not placed higher than that the sow can easily climb over the threshold and pass in and out through the shutters. In order to further obstruct and deter the piglets from trying to pass through the shutters, the threshold can be provided with a ledge 11 of e.g. rubber, and approx. 10 cm high. This gives an impression that the threshold is very high. However, the rubber ledge is so provided that it yields or bends when the sow bumps into it, and thus it does not hinder her from passing in or out through the shutters. In order to further enhance the difficulty for the piglets to get out, the upper

edge of the ledge can be bent inwardly, such that an overhanging portion is formed. By virtue of the flexibility of the rubber the sow is still not noticeably hindered. The swingable shutters 8, 9 can also be provided with locks. As shown in Fig. 3 the gate can also be provided with two smaller shutters 12, 13 for the piglets. These shutters are also swingable and self-closing, and they can also be provided with locks.

In order to further illustrate the advantage with the installation according to the present invention, the work sequence during the time from the farrowing upto the point when the sows are separated from the piglets, will be described below.

As mentioned in the preamble, pigs have a natural, instinctive behaviour, involving that they prefer having particular locations for different activities. In order to satisfy these behavioural needs in a modern installation for breeding of pigs, it is of importance that the pigs be able to move about relatively freely within the installation. This is made possible in the following way:

The one sow being the first of a number of sows to farrow, is placed in the first stall 1 in a row of equivalent stalls positioned one adjacent to the other. Thereby the gate protecting the piglets is swung to its first position A (see continous line in Fig. 1), and the gate 8 is locked in position D. Thereafter the sows are placed in the following stalls in the order of their farrowing. After all of the piglets in one litter have been born, they have the space in the corner of the stall under the heating lamp 4 at their disposal, whereby the gate is closed to its second position B (broken line in Fig. 1) as a protective means for the piglets. Thus the sow during this time has free access to the manure passage and to the stall, while the piglets have no possibility to exit or enter the stall. This possibility for the sow to move freely leads to that she becomes calmer and,

when being fed from the feeding trough 6, less prone to i.e. show stress symptoms and thus by mistake tread on and kill her piglets. When the piglets have reached the age (approx. 6 weeks) when the sow is removed from them, the gate 8 is swung to the position indicated by a continous line. It is to be noted that the first born litter that was placed in stall 1, also is the one that first is separated from the sow. Thus the gate 8 will not hinder access to the manure passage for the rest of the sows, not yet having been separated from their piglets. In the position C all shutters are locked as well as the gate, such that the piglets dispose of a stall for themselves.

Thus, essentially the following eight advantages are achieved with the installation according to the present invention.

1) The sows become considerably calmer, since they in a more natural way than before can move relatively freely within the installation. This leads to a considerably reduced risk that the sows when being stressed tread on and kill their piglets, or as might occur, simply bite them to death.

2) This increased movability with accompanying freedom, has shown that the sows preferably give off their dung and urine in the manure passage, leading to a considerable reduction in the labour required to clean the installation.

3) These cooperating factors bring about a considerably enhanced productivity.

4) The sows show earlier heat and can be covered considerably earlier than in present systems. Since the sow has a possibility to leave the farrowing stall she may herself in a more natural way decide when to feed the piglets. In addition, she will make contacts outside the stall with other sows and with the boar. In a pilote investigation with twelve sows, all these factors contributed to that the sow showed early heat and could be covered within 26 days on an average after the

farrowing. These results are to be compared to the state of affairs in present systems with a covering carried out 45-47 days after farrowing and with a weaning period of 6 weeks.

5) The system is easily adaptable to the present conventional installations for breeding of pigs.

6) The system also makes it possible to modify conventional installations, such that sows have a possibility to reside outdoors during seasons when this is appropriate.

7) The system is very suitable for "batch"-farrowing, where several sows (usually 6) farrow within a few days.

8) The system can with advantage be combined with modern feeding systems, where transponders in collars or in ear marks can individually regulate the feed allocation to each animal in automatic feeding machines. This type of feeding system gains at present more and more interest within the field of pigbreeding (cf. "Svinskδtsel", No. 10, 1984, p. 34).

The gate characteristic of the installation can have several embodiments, as disclosed in the appended patent claims.