Detailed Explanation of Modern Pig Farm Design Plans and Construction Key Points
China has a long history of pig farming and abundant resources for developing the pig industry, including pig breed resources, feed resources and the rural tradition of raising pigs, but its pig farming technology is relatively backward, with problems such as low labor productivity and a low commodity rate. In recent years, as the number of specialized rural households has increased year by year and pig farming science and technology have become increasingly widespread, the specialized pig farming industry has also gradually consolidated and prospered.
Combining the relevant professional knowledge and the experience of visiting pig farms, taking an annual output of 1000 fattening pigs as an example, a modern pig farm construction plan is drafted. According to mechanized pig farming and rearing techniques, a preliminary discussion is made on the functional and production buildings, auxiliary buildings and pig farm mechanization planning and design.
Basis for Planning and Design
A pig farm with an annual output of 1000 fattening pigs needs to raise 2 breeding boars on hand, 83 producing sows, 100 nursing piglets, 1000 nursery pigs and 370 growing-finishing pigs. The planning and design of mechanized pig farming is mainly based on rearing techniques. At present, the all-in-all-out rearing technique with a weekly rhythm is generally adopted. This design adopts early weaning (10-20 days of age) and isolated rearing.
Process characteristics: early weaning (10-20 days of age) and isolated rearing are new pig farming techniques. Early isolation weaning means that, according to the diseases that the pig herd itself needs to eliminate, weaning is carried out within 10-20 days of age, and then the piglets are sent to a clean area nursery house more than 250m away from the farrowing house for isolated rearing. This is the early weaning (10-20 days of age) two-site isolated rearing system. The newly developed SEW rearing technique can increase the number of litters produced by sows, cut off the routes by which piglets are infected by sows or other older pigs, and improve piglet health.
Planning and Design
1. Site selection. The selection of the site is crucial to pig farm production and should mainly consider the following aspects:
① Long-term planning. Today's society is developing rapidly, and urban and rural construction is changing with each passing day. Pig farming is a long-term industry, so pig farm construction should conform to urban development. If it can become part of the urban food basket project and the pig farm is built in a livestock production base designated in urban planning, the awkwardness of demolition can be avoided. In order to isolate dust, odor and noise, the pig farm should be located downwind of residential areas, at a distance of more than 300-500m, and no less than 100-200m from major traffic lines, and the selected site should have enough room for expansion.
② Orientation of the pig houses. Pig houses should face south, and may also have a certain deviation according to terrain and latitude, so as to facilitate sunlight and heating in winter and windward cooling in summer. Modern mechanized pig farming uses artificial climate control, so the requirements for orientation are not strict, and more attention is paid to convenient centralized management and the realization of mechanized production.
③ Factors such as water, electricity and transportation. A 1000-head mechanized pig farm has a daily water consumption of 16t, so a clean and stable water source must be considered first. The installed capacity of the pig farm is relatively large, generally 30kW, and power cannot be cut off. Once power is cut off, pigs cannot drink when thirsty, cannot be ventilated and cooled when hot, and piglets cannot be heated and kept warm when cold, which will seriously affect production. Therefore, it is best to build the pig farm in an area with a stable power grid supply, and at the same time a small generator should be provided to guard against the unexpected. For a 1000-head pig farm, about 4t of feed, manure and live pigs enter and leave each day. Building the pig farm in a location with convenient transportation can reduce transportation costs.
④ Sanitation and epidemic prevention. In order to maintain good sanitation and epidemic prevention conditions, the site should be selected in a place with relatively high terrain, open terrain and good ventilation, and at the same time be far away from residential areas, medical institutions, slaughterhouses and other places. It is best to have only one entrance and exit passage.
⑤ Manure and sewage treatment. The amount of manure and sewage from a 1000-head pig farm is very large. If it cannot be treated promptly and effectively, it will pollute the surrounding environment and cause ecological imbalance. Therefore, the selection of the site should consider being far away from drinking water sources, and at the same time leave space for sewage treatment. Manure treatment should be combined with fish pond aquaculture, fruit and vegetable planting and other crop production to turn waste into treasure; the manure can also be dried and sold as fertilizer.
2. Functional area planning
The overall layout design of a mechanized pig farm mainly proceeds from the perspective of a three-dimensional sanitation and epidemic prevention system and production management, and is divided into several areas according to function. Generally, the pig farm is divided into production buildings, production auxiliary buildings and production management buildings. Production buildings include farrowing pig houses, breeding pig houses, finishing houses, etc. Production auxiliary buildings include feed workshops, water towers, boiler rooms, warehouses, power distribution rooms, veterinary rooms, slaughter rooms, loading platforms, etc. Production management buildings include administrative offices, dormitories, etc. Production management buildings should be separated from production buildings, and production auxiliary buildings should also be separated from production buildings as much as possible, so as to help control the occurrence of epidemics; however, production auxiliary buildings should be arranged around production buildings to facilitate production. In terms of terrain, production buildings and production auxiliary buildings should be lower than production management buildings and be downwind; veterinary rooms and manure storage tanks should be lower than production buildings and be in a more downwind direction.
Modern pig farms establish specialized pig houses according to different production stages, such as breeding houses, farrowing houses, nursery houses, etc. The distance between pig houses should be no less than 20m. The layout of pig houses should facilitate the turnover of the pig herd. The last process, such as the nursery house of a breeding farm and the
finishing pig house of commercial pigs, should consider convenient transportation so as to facilitate the shipment of products. The pig houses should be connected by roads or corridors to reduce the distance of water, electricity and heating lines and improve work efficiency. The breeding herd and commercial herd within the pig farm should be separated, with a certain epidemic prevention distance maintained between the two herds, and the breeding herd should be in the downwind direction. Feed storage and loading platforms should be set at the boundary of the production area to prevent vehicles from outside the farm from entering the production area, which is conducive to epidemic prevention. The area around the farm should be landscaped, and trees should be planted to regulate the microclimate.
3. Planning and design of buildings in the production area
When carrying out the floor plan design of pig houses, the first step is to calculate the number of pigs to be raised and the number of pens in each production stage according to the mechanized process flow, and then carry out the floor plan design. The following takes an annual output of 1000 meat pigs as an example to calculate the number of pigs to be raised and the number of pens at each stage.
(1) The number of pigs at each production stage. The adoption of the SEW rearing technique shortens the suckling time, and the annual number of litters produced per sow is increased to about 2.3 litters/year (2.1 litters/year for the general technique). For an annual output of 1000 meat pigs, the number of producing sows needed is: 1000÷2.3 litters/year÷10 pigs/litter÷90%÷95%=40.85 head. Take 51 head (among which: 90% is the survival rate of suckling piglets; 95% is the survival rate of piglets), which is 10 fewer sows than the general rearing technique. Calculated on the basis of 51 sows, the whole farm needs to keep 2 boars. Number of litters per week: 51×2.3 litters/year÷52 weeks=2.256 litters. That is, each week 2.256 sows are mated successfully and 2.256 sows farrow. Number of piglets born per week: 2.256 head×10 pigs/litter=22.56 head. Meat pigs marketed per week: 22.56 head×90%×95%=19.29 head, take 19 head. Meat pigs marketed in the whole year: 52×19=988 head.
(2) Number of pens
① Boar pens. 2 pens, each with an area of 5.04m2 (2.4m×2.1m).
② Individual sow pens. Total number of producing sow pens - number of sow pens in the farrowing house = 51-(3 weeks×2.256 head/week)=44.2 head. Considering factors such as replacement sows, take 43 pens, each with an area of 1.26m2 (2.1m×0.6m).
③ Farrowing pens. Pregnant sows enter the farrowing pens one week before farrowing. The farrowing pens are cleaned and disinfected 3 weeks before farrowing and 1 week after farrowing, for a total of 5 weeks. Number of farrowing pens=number of farrowing sows per week×5=2.256×5=11.3 pens, take 11 pens, each with an area of 4.07m2 (2.2m×1.85m).
④ Nursery pens. Newborn piglets enter the nursery pens, 2 litters are combined into 1 litter, the nursery period is 6 weeks, with 1 week for cleaning and disinfection, for a total of 7 weeks. Number of nursery pens=number of farrowing sows per week÷2×7=2.256÷2×7=7.896 pens, take 8 pens, each with an area of 8.1m2 (3m×2.7m).
⑤ Growing and finishing pens. Growing pens and finishing pens usually hold 2 litters per pen. The growing period is 6 weeks (1 week for cleaning), and the finishing period is 11 weeks. Number of nursery pens=number of farrowing sows per week÷2×6=2.256÷2×6=6.768 pens, each with an area of 16.2m2 (5m×2.2563m). Number of finishing pens=number of farrowing sows per week÷2×11=2.256÷2×11=12.4 pens, take 13 pens, each with an area of 24m2 (5m×4.8m).
4. Floor plan design of various pig houses
According to the number of pig pens, the floor plan design of the pig houses can be carried out. The main principles of pig house floor plan design are:
① The width of the pig house should mainly consider summer ventilation and cooling, so pig houses are generally designed in 2 rows, with a house width of 7.5-11m.
② The length of the pig house mainly considers convenient waste discharge. The lengths of various pig houses should not differ too much, which is conducive to making full use of the land. Generally, the length of a pig house is 60-100m. According to the above principles, the various pig houses of a 1000-head pig farm are: 1 house for replacement breeding boars (15m×7.5m), 1 house for breeding boars (15m×7.5m), 1 house for replacement breeding sows (25m×7.5m), 1 house for open sows (10m×7.5m), 2 houses for pregnant sows (25m×7.5m), 2 farrowing houses (25m×10.5m), 2 nursing and growing houses (25m×7.5m), 1 growing house (25m×11m), and 2 finishing houses (15m×11m).
The floor plan design of pig houses should note the following points: First, all pig houses should preferably be arranged in 2 rows according to the process flow, which is convenient for management and epidemic prevention; second, pig houses should face south, as sufficient sunlight can play a role in sterilization and disinfection and in lighting and heating in winter. If limited by terrain, the orientation can vary between 5° south by west and 15° south by east; third, from the perspective of ventilation and epidemic prevention, the spacing between pig houses should be 2-2.5 times the height of the pig houses, generally no less than 9m.
5. Planning and design of other buildings in the production area
Other buildings in the production area mainly include pig loading platforms, manure loading platforms, biogas digesters, feed rooms, veterinary rooms, personnel disinfection rooms, vehicle disinfection rooms and roads. Their planning and design should mainly note the following points:
① The production area should preferably have only one entrance and exit, with personnel disinfection, vehicle disinfection and a duty room.
② The pig loading platform and manure collection tank should be placed outside the enclosure wall, so that external pig and manure transport vehicles can operate without entering the production area.
③ External vehicles transport feed to the feed room, and then vehicles within the production area transport the feed to each pig house.
④ For the road setting in the production area, roads within the area can be roughly divided by use into pedestrian paths, feed roads, and pig and manure transport roads.
⑤ Isolation pig houses should be far away from production pig houses and be in the perennial downwind or crosswind direction.
⑥ Water sources and power sources should be close to each pig house for convenient use and reduced waste. At the same time, practical protection measures should be taken for water sources to avoid contamination, and safe electricity use should be ensured for power sources.
⑦ Manure and sewage treatment should be planned in a unified way and fully utilized in accordance with actual conditions. Attention should also be paid to separating sewage and rainwater to reduce the amount of sewage treatment.
6. Building planning of the office and living area
The office and living area should be designed far away from the production area and placed in a superior location. The planning of the office area should facilitate management, especially the disinfection management of external personnel and vehicles.