This depends on the specific circumstances. In production practice, the ratio of male to female pigs is 1:20 to 30 in the case of natural mating. If the number of breeding sows in small-scale pig farms is small, and there are large-scale breeding farms or breeding boar stations nearby that provide sufficient semen, artificial insemination can be performed on the site. There is no need for specialized breeding of breeding boars. The trial boar can be. Of course, if it is difficult to obtain boar semen from other farms, a certain number of boars, at least one or more, should be kept on the farm, regardless of size, to prevent boars from using enough boars or individual boars when the sow concentrates on heat. Sudden illness caused special circumstances such as use without boars.
Greenhouse Film Manual Roll Up
The Greenhouse Film Electric Roll-Up Unit replacing traditional manual roll-up unit to reach high speed automation in revolving & releasing films and greenhouse environment, it is the new generation of greenhouse ventilation and temperature regulation facilities. Portability, output torque, output lock, wide range and precise adjustment, waterproof, dew-proof and power-saving are the key characteristics for Electric Roll-Up Unit, which is the best choice for modern daylight greenhouse applied in different climates.
Greenhouse Film Manual Roll Up,Greenhouse Manual Winch,Greenhouse Side Film Roll Up
JIANGSU SKYPLAN GREENHOUSE TECHNOLOGY CO.,LTD , https://www.skyplantgreenhouse.com