How many days is it best for sows to be weaned in estrus and mating next time?

First, the concept of sow estrus cycle

1. Pre-estrus, estrus, post-estrus, bisexual period (estrus);

2. Generally 2 1 day (18-23 days);

3. Estrus lasts about 2-3 days, luteal phase is about 13- 14 days, and follicular phase is about 3-5 days.

Second, the duration of sow ovulation.

The average duration of sow ovulation is 4 or 5 hours, and the longest is 10- 12 hours. The duration of sow ovulation is 6 hours at the shortest and 20 hours at the longest.

Third, the ovulation start time of sows

Ovulation period is mostly after the start of standing estrus 16-48 hours. Generally, it is 24-36 hours after estrus, and 4-7 days after weaning is exactly 24-36 hours after estrus. The earliest ovulation start time of sows is 14 hour after estrus, and the latest is 4 1 hour after estrus.

Fourthly, the survival time of sperm in sow reproductive tract.

Because sperm can survive for up to 42 hours in the reproductive tract of sows, the time for sperm to have fertilization ability is only 25-30 hours. The survival time of sperm in sow reproductive tract is 20 hours.

Five, the egg has the ability of fertilization time.

The fertilization time of an egg is 8 ~ 10 hour, and the longest time is 15 hour. Generally, the time for an egg to be fertile is 8 hours.

Sixth, the best breeding time.

The first statement:

Before ovulation, especially a few hours before ovulation peak, that is, 2-3 hours before ovulation; In other words, mating begins at 12 ~ 24 hours after estrus begins (the time when estrus begins refers to the time when mating wants to accept climbing), and mating is repeated every 8 hours.

The second statement:

Weaning in 3 or 4 days-breeding begins 24 hours after standing for reaction.

After weaning at the age of 5 or 6 days-standing for reaction 12 hours, mating began.

Weaning on the 7th, 8th and 9th days-forced matching after standing, and matching immediately.

Estrus occurs 3 days after weaning, and the best mating time is about 1 1 hour before ovulation.