Precautions for ventilation management in pigsty

The ventilation of pig houses is very important because of the hot summer. Manzhouli agricultural technology extension personnel came to pig farmers in the area on July 18, 2016 to publicize the matters needing attention in pig house ventilation. At present, the ventilation methods used in most small and medium-sized pig farms can be divided into roof ventilation, transverse ventilation and longitudinal ventilation.

Ventilation on the roof. Roof ventilation means that the air in the pigsty flows up and down by means of the density difference between different gases without mechanical equipment, so that the waste gas in the pigsty can be discharged from the roof in time. Roof ventilation can greatly reduce the concentration of exhaust gas in the pigsty, ensure fresh air in the pigsty, and reduce the incidence of respiratory diseases; for the pigsty with foot ventilation windows and leaking fecal floor, roof ventilation makes the fresh and cool air blow directly to the pig body from the foot ventilation window of the pig house, taking away the heat emitted by the pig and the exhaust gas, which can play a significant cooling role, especially after flushing the pigsty in summer. Roof ventilation can choose to open windows on the roof, install roof unpowered fans or roof fans and so on.

Lateral ventilation. Lateral ventilation is generally natural ventilation or the installation of fans on the walls, which is mainly used for the ventilation of open and semi-open pig houses. In order to ensure the smooth ventilation of the pig house, full consideration must be given to the site selection, the layout and direction of the pig house, and the design of the pig house. It is best to make the pig house perpendicular to the local main wind, so as to maximize the use of lateral ventilation. The air inlet of transverse ventilation is generally composed of glass windows and shutters. When installing shutters, the curtains should overlap with the sidewall about 8 cm, so as to prevent thieves from entering; at the same time, fly-proof nets should be installed on the inside of the curtains to prevent flies and rats from entering to ensure biosafety; the shutter had better be opened from top to bottom, allowing exhaust gas to be discharged from the top of the shutter to balance ventilation and heat preservation.

Longitudinal ventilation. Longitudinal ventilation usually adopts mechanical ventilation, which can be divided into positive pressure longitudinal ventilation and negative pressure longitudinal ventilation. Generally speaking, positive pressure longitudinal ventilation is mainly used for pig houses with poor tightness, while negative pressure longitudinal ventilation is used for pig houses with good tightness, which forcibly draws the air out of the house through the fan to form negative pressure, so that the air outside the house enters the house through the air intake under the action of atmospheric pressure.

The harmful components in the air of pig house are mainly ammonia, hydrogen sulfide, carbon dioxide and dust, among which ammonia and hydrogen sulfide have the greatest influence on the production performance and health of pigs. in order to ensure the normal growth performance of animals, it is necessary to control the concentration of these harmful gases through reasonable ventilation, so that the air hygiene quality of pig houses can meet the requirements.