How is summer pig farm best for heatstroke prevention?
1.1 reasonable site selection
No matter whether it is a large-scale pig farm or a local pig breeding base in China, the site must be located in a place with high terrain, dryness, good ventilation and sufficient water, and it is forbidden to choose a place with leeward and nest wind.
1.2 building layout
besides epidemic prevention and lighting, ventilation should also be considered in the layout of pig farms and the spacing between pig houses. The layout should be reasonable and the spacing should not be too small, generally not less than 1m.
1.3 pigsty span
The pigsty span also affects the ventilation effect. The pigsty with small span has short and straight ventilation route and smooth airflow. If the span exceeds 1m, if necessary measures are not taken, the ventilation effect will be poor and it will be difficult to form a draught.
1.4 pigsty orientation
pigsty orientation has certain influence on ventilation and cooling. In hot areas, besides reducing solar radiation and preventing storms, the main wind direction in summer must be considered at the same time, which is beneficial to ventilation and cooling and reducing energy consumption.
1.5 internal structure of piggery
In order to be more conducive to ventilation, it is not advisable to set a partition wall in the piggery, and the partition walls of each circle, especially the partition wall between the piggery and the passage, can be replaced by iron fences.
2 thermal insulation of piggery
2.1 building methods and materials
The strong solar radiation roof in summer is easy to transfer the radiation heat into the piggery. In order to improve the thermal insulation performance of the roof, ventilation roof can be adopted, that is, the roof is built into two floors, so that the air between the floors is lightened and discharged from the exhaust port, and cold air flows in from the air inlet, thus reducing the heat transmitted to the bottom of the roof; You can also use materials such as white foam board with a thickness of more than 5cm under the roof of the pigsty as a thermal insulation layer to prevent thermal radiation; The new energy-saving and environment-friendly pigsty wall panels and roof panels produced by Qingdao Pairu Environmental Technology Co., Ltd. are made of special color steel polystyrene composite panels, with a thickness of .5mm, a thickness of 1mm on the wall and a thickness of 15mm on the roof, and a density of more than 12kg/m3 (other thermal insulation panels can meet the thermal insulation effect). The pigsty thus built has good sealing performance, and can be warm in winter and cool in summer with certain environmental control system, so that it is not necessary to burn coal for heating in winter.
2.2 sun-shading facilities
If the structure of the pigsty cannot be changed in essence, sun-shading facilities can be installed, and certain facilities can be used to block solar radiation. For example, a water plate can be added to the window to block the sunlight from the upper part of the window, and a sunshade net and a sunshade awning are installed outside the pigsty to prevent the sunlight from directly shining on the pigs or inside the pigsty; White cement or white heat insulation paint for building should be used to whitewash the walls of piggery with long sunlight to reduce heat radiation.
3 heatstroke prevention and cooling
3.1 greening
Pig farm greening is one of the fundamental and effective measures to improve the environment and create favorable pig production and life. Greening not only has the functions of purifying the air, improving the microclimate and beautifying the environment, but also has the functions of alleviating solar radiation and lowering the environmental temperature. Fu Shilun's research on the effect of greening and shading shows that greening and shading has a significant effect on improving the microenvironment of pig farms. In summer, we should reduce solar radiation heat as much as possible by greening and shading. When the external environment temperature is higher than that in the shed, the surrounding buildings can also be radiated to raise the temperature in the shed, and air can bring heat into the shed through doors, windows and ventilation holes. Planting trees and greening is helpful to reduce the ambient temperature around the pigsty. The area of leaves is 75 times of forest planting area, and the area of grass leaves is 25 ~ 35 times of grassland area. These leaves, which are dozens of times larger than the green area, absorb a lot of solar radiation heat through transpiration and photosynthesis, which can significantly reduce the air temperature. Therefore, more trees and grass should be planted in and around the pig farm to reduce the environmental temperature. However, we should pay attention to the fact that tall trees should not be diversified, which will affect ventilation and attract wild birds, which is unfavorable to epidemic prevention.
3.2 Strengthen ventilation
In summer, when the temperature inside the piggery is higher than that outside, ventilation can take the heat out of the piggery, increase the air flow speed inside the piggery, take away the heat when passing through the pig, and promote the evaporation and heat dissipation of the pig. Natural and mechanical ventilation can be used to increase the air flow in the pigsty and increase the heat dissipation speed of the pig body surface. Ceiling fans, industrial fans or blowers can be selected to increase the air flow in the pigsty and achieve the purpose of cooling the pig body. If properly combined with ground sprinkling, the effect will be better.