When sows are mated, detailed records should be kept of the date of breeding and the species and number of the boars. Once it was concluded that the sow was pregnant, it was necessary to calculate the date of the expected date of production so that it would be easy to raise and manage and prepare for the production. The sow's gestation period is 110 to 120 days with an average of 114 days. The estimated sow's due date is based on 114 days and can be calculated as follows.
Three-three-three methods. In order to facilitate memory, the sow's pregnancy can be recorded as 3 months, 3 weeks and 3 days.
Matching month plus 3, mating day plus 20 method. That is, plus 3 months on the sow mating month and 20 days on the breeding day, the resulting date is the expected date of the sow. Examples include mating on March 1st, delivery on June 21st, breeding on March 20th, and delivery on July 10th.
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