The pig bar is a necessary equipment for industrial pig farms. It is used to fence pigs of different types and different ages to form the basic production unit of a pig farm. The reasonable feeding density, suitable breeding environment, and convenient feeding and management conditions of pigs are closely related to the form, structure, material, arrangement and arrangement of pigs. With the further development of intensive pig production and further understanding of the biological characteristics of pigs, people questioned whether the current popularity of pig pens meets the production and living requirements of pigs. The author investigated the current status of pigsheds in factory pig farms, and based on the characteristics of the pigsheds, combined with the behavior of pigs, put forward a new idea for pigshed design.
1 Current species and characteristics of pigsheds
The structure, size, height and density of railings, selection of materials, etc. are different. These should be designed based on the characteristics of the herd. The materials used to make railings are generally adopted in China today. They are made of metal structures such as round steel, flat steel, and angle steel, and some are used.
Reinforced concrete prefabricated pig bar, the lowest cost is a brick pigshed.
The current pig pens are usually divided into male pens and breeding pens, (pregnant) sows pens, farrowing pens and nursery pens, nursery pens, growth pens, finishing pens, gilts, etc.
1.1 Boar Bars and Breeding Columns The current factory pig farms have the following two methods for the configuration of the boar and breeding bar: The first configuration is the close configuration of the sow bar and the male bar. The four sow pens correspond to one boar bar, and no special breeding bar is provided. The boar bar is also a breeding bar. The sows to be paired after weaning are kept in the monomer feeding column.
Behind the sow pens, a boar bar houses a boar for each boar, which facilitates the use of boars to help detect estrus. When mating, the sows in the sow pen can be released and allowed to enter the pens for breeding. After the breeding is completed, the sows can be returned to the original sows. The advantage of this configuration is that it will not miss the suitable period for breeding, but also facilitate management and increase labor productivity. The second configuration method is the relative configuration of the sow bar and the boar bar separated channel. There is no special breeding bar, and the boar bar is also the breeding bar. When the breeding is done, the sow is rushed to the boar for mating. Although male and female pigs can not be directly contacted, if iron fences are used, they can also wait and see each other, which is conducive to estrus identification.
The boars are generally kept as a single animal. The height of the pens is 1.1-1.2 meters and the area of ​​each pen is 4-6 meters. If it is used as a breeding column, the area should be slightly larger. The structure of the boar bar can be either concrete or metal. In order to maintain and enhance the breeding ability of boars, some boars also have open-air playgrounds.
1.2 Pregnancy Sow Bars Most of the current factory pig farms keep pregnant sows raised in a single column, which can prevent sows from biting each other, colliding, fighting each other, reducing pregnancy abortions, and raising the survival rate of calving. It is easy to observe the estrus of the sow and perform breeding in time; the pregnant sows are bred in one zone according to the breeding time, so that the keeper can reasonably feed according to the length of the gestation period to facilitate the operation and improve the management level; the porcine bar covers a small area and can be reduced The construction area of ​​the pig house; the use of a single column also facilitates the mechanization of feeding, water supply and excrement removal. The single limit column for pregnant sows is generally made of metal structure, and the size is 2.1-2.2 meters long, 0.55-0.65 meters wide and 0.9-1.1 meters high.
1.3 Farrow pens and nursing pens The sows' litter and lactation are the most important links in the production of pigs in factories. The design and construction of a reasonable litter bar are closely related to ensuring normal sows delivery and improving piglet survival. Most pig farms in industrialized pig farms have their farrowing pens and nursing pens set up to meet the special requirements for feeding and management at this stage: (1) Sows and piglets feed on different feeds. (2) The sow and piglet have different requirements for ambient temperature, the sow's suitable temperature is 15-18°C, and the piglet after birth needs 30-32t.
Therefore, additional heating equipment is provided for suckling piglets. (3) Strict requirements for environmental conditions such as temperature, humidity, harmful gas, and indoor air flow rate in litter sows and newborn piglets. Therefore, the farrowing pens and nursing pens should be easy to clean and disinfect to prevent the accumulation of dirt and bacteria. The ground roughness should be moderate, drainage is good, and it is easy to dry after cleaning. The floor is too smooth to make the pig slip, too rough and easy to scratch the pig's feet and knees. The air is fresh, but no blasts come in. (4) To protect the piglets from being crushed or trampled by the sow, facilities such as a protective frame or pressure bar shall be provided.
The farrowing nursery bar generally consists of three parts: (1) Sow tiller limit column: Its role is to limit the sow's turn and back, and the lower part of the limit bar has a bar-shaped or dentate-shaped bar, so that the sow When you lie down, you don’t hold down the piglets, and the piglets can use this stall to eat. The size of the limit bar is generally 2-2.1 meters long, 0.6 meters wide, and 1 meter high. There is a sow trough and a drinking fountain in front of the limit bar. (2) Activity area of ​​suckling piglets: Surrounded by a fence of 0.45-0. 5 meters high, the piglets are inserted in them, feeding milk and drinking water. There are feeding troughs and drinking fountains in the activity area. (3) Piglets Incubators: Electric heating plates or infrared lamps are installed in the boxes to provide heat for piglet heating.
This kind of litter-feeding bar is generally made of metal structure, but it is also surrounded by bricks or cement boards, and the metal limit structure is still used for the delivery limit bar. The length of the entire column is 2.1-2.3 meters and the width is 1.5-2 meters.
Some factory pig farms increase the total number of litters on the farrowing bar by about 0.4 meters, which means that they become high-potted litter-feeding sows. In the farrowing area and the piglet movement area, there are half metal leaky joints, half board, or all metal leaks. Slit plate. This high-bed, litter-fed nursing bar separates sows and piglets from cold and cool ground. The inside of the bar is warm and dry. Defecation is also very convenient. This improves the living conditions of sows and piglets. The incidence of piglets is greatly reduced and the Piglet survival rate in winter and spring.
1.4 Young pig rearing bar This bar is for young pigs aged 70-77 days after weaning. During this period, the pigs were just weaned and left their mothers to live independently, and their ability to digest and adapt to environmental changes was not strong. Need a clean, dry, warm, low wind speed and fresh air environment. Most of the online cultivating bars are used. The net is 0.3-0.5 meters above the ground. The young pigs are separated from the cold concrete floor. The bottom net is woven with steel wire. There is a board on one side for the young pigs to lie down, and the drinking fountains and mining are installed in the columns. Food container. Young pig larvae are generally 1.8 meters long, 1.7 meters wide and 0.7 meters high. The columns can feed 10-12 young pigs, just raising a litter of young pigs.
1.5 The growth bar, finishing bar, and gilt bar are basically the same in the structure of the three columns, except that they vary in size due to the number of heads and the size of the pig. The growth bar and the finishing bar advocate the breeding of the original nest. Therefore, the pigs in each pen have 8-10 pigs and are equipped with feeding and drinking devices. The size of the growth bar is generally 2.7 meters long, 1.9 meters wide, 0.8 meters high, and the spacing between the bars is 100 millimeters. The size of the finisher bar is generally 2.9 meters long, 2.4 meters wide, 0.9 meters high and a spacing of 103 millimeters between the bars; the gilt bar is usually fed with 4-5 heads per bar, and the gilt bar is generally sized. It is 2.1 meters long, 2.4 meters wide and 0.9 meters high. The spacing between the bars is 103 millimeters.
2 pig bar design new ideas
Pig behavior should be considered as an indicator of performance evaluation when designing pig stalls. Only in this way can a series of problems such as declining production performance, increased morbidity, and poor environment due to behavioral problems be avoided. Therefore, it is necessary to consider behaviors from pigs. From the perspective of investigating the new thinking of the pig bar design.
2.1 The disadvantages of using solitary columns in pregnant sow pens are the consumption of materials, large construction investment, small movement range of sows, limited activities, small exercise, easy to produce leg and hoof, and shortening of mothers. The useful life of pigs requires careful planning and careful management. In order to solve these problems, it is also possible to keep pregnant sows in large columns, and to set a number of short fences at the feeding site to prevent sows from biting due to competition for food.
2.2 Farrowing pen and feeding bar
2.2.1 Maintaining regular mother's visual, tactile and auditory connections plays an important role in increasing maternal love and improving the sense of safety of piglets. The sow has to maintain regular contact with each piglet postpartum. The most obvious example is when the sow is away, always looking at her own piglets. Somatic contact between sows and piglets is an important indicator that sows actively participate in the growth and development of piglets. However, in the case of quail-feeding and the sows are placed in the limit frame, especially when the piglet enters the incubator, this contact is limited, which has a detrimental effect on the growth and development of the piglet.
The existing litter box insulation boxes are mostly set at the corner of the limit frame, far away from the lying position of the sows, especially far from the sow breast area, which is not favorable for the piglets to look for the incubator after birth and quickly go out of the breast after coming out of the incubator. . According to the sow's constant visual contact requirements, the sow lying area is preferably located opposite the incubator, and the piglets can expose their heads from the incubator so that the sow can instinctively gaze at the piglets and facilitate the rapidity of the piglets. Bring a sow to the sow.
2.2.2 Insufficient size of the incubator box is an important reason for pigs not being able to lie down sideways due to their inherent behavioral habits, causing crowding and exacerbating fighting and biting. The plane size of the suckling piglet incubator should be increased by more than 50%, and the area per head of the incubator incubator should reach 0.113m2. Only in this way can the behavioral engineering design requirements be met. At present, Germany, Switzerland and other countries are beginning to popularize a new type of incubator with an open front end and curtains.
This structure meets the requirements of the pig's breathing fresh cool air, while the body part is in a warm and comfortable environment, worthy of our reference. Insulation box materials have poor insulation properties and have more heat loss, which is not conducive to their full extension of limbs to rest. Considering the pig's lying posture, the incubator heating method is best to use the ground heating method.
2.2.3 Sow farrowing pens can reduce the mortality of suckling piglets, but excessively restricting sow activity can cause many behavioral and other problems. After entering the farrowing pen, the sow’s behavior was significantly reduced, and there was no opportunity to show digging, searching, and nesting, and the amount of exercise was greatly reduced. This caused problems such as prolonged sows’ delivery time, dystocia, and indigestion. The imprisonment for more than two months per year (2.1-2.3 litters per litter) is also very likely to result in a decline in the conception rate and health of the sows, thus forcing the sows to be eliminated in advance and causing significant losses to the production.
In order to avoid the above problems, while enlarging the flat size of the farrowing bar, it may be considered to set the straw frame at the far side of the defecation area, so as to meet the inherent behavioral requirements and reduce the pressure and injury of the piglets. dead. It has been shown that the shape and structure of the fence influence the behavior and the lactation of the sow. In fence-like pens, sows are more likely to have hostile emotions with the sows in the adjacent column and affect lactation, which can also result in fierce competition for the piglets during breastfeeding. Therefore, it may be considered to change the fence into a monolithic type to minimize the mutual influence and stress of pigs in adjacent columns.
2.2.4 The sow limiter size currently in common use is 2.20mx 0.65m. In order to provide a more spacious space for the sows to be born, consideration can be given to making the sow limiter adjustable, that is, during labor and postpartum. Within the week, the limit frame is kept in the original plan size. After the danger period of the piglet is adjusted to open in the second week, it presents a triangle, creating a larger exercise space for the sow. At the same time, this practice can also reduce the squat phenomenon of sows in the limit frame, so as to avoid causing the piglets to be crushed or crush.
2.3 Rearing Bars and Finishing Bars The breeding bar and finishing bar currently used in China are basically reared on the same group of litters as the basic group. Although this practice has reduced the mutual biting and tussle phenomenon when nesting, but the pig is in a narrow single-bar space, it will seriously affect the intake, defecation, and normal rest, even when eating phenomenon.
The ideal solution is to change the head of small groups (8-10) to large heads (100-120), change the small single column to large columns, and set several incubators for pigs to rest and sleep. In this way, short-term pigs can choose different incubators based on their own weight, community status and strength, naturally form communities, reduce fighting and other undesirable behaviors, and open special breeding boxes for sick pigs and weak pigs. .
The piglets have a playfulness and like to use the behavioral requirements of snuggling objects and digging the ground. On the rearing bar, play chains and recreational automatic hay boxes can be set to maximize the surrounding environment. Not only can it meet the requirements of ground excavation and other behaviors, but it also has great benefits for increasing oral saliva and improving the gastrointestinal digestive capacity of piglets.