The estrus cycle is a series of hormonal and physical changes that a female hog undergoes in preparation for breeding. The estrus cycle in hogs is typically 18-21 days long, with an average of 20 days.
Stages of the Estrus Cycle
The estrus cycle is divided into four stages:
Proestrus: This stage is characterized by increased estrogen production from the ovaries. The sow’s vulva will be swollen and red, and she may show signs of excitement, such as rubbing against objects and making vocalizations. Opens in a new window www.mdpi.com Proestrus stage of estrus cycle in hogs
Estrus: This is the stage when the sow is receptive to breeding. She will stand still when a boar mounts her. Opens in a new window porkgateway.org Estrus stage of estrus cycle in hogs.
Diestrus: This stage is characterized by decreased estrogen production and increased progesterone production. The sow’s vulva will be smaller and less red, and she will no longer be receptive to breeding. Opens in a new window www.researchgate.net Diestrus stage of estrus cycle in hogs
Metestrus: This stage is characterized by regression of the corpus luteum, the structure that produces progesterone. The sow’s vulva will be small and pale, and she will not be receptive to breeding. Opens in a new window www.thepigsite.com Metestrus stage of estrus cycle in hogs
Signs of Estrus in Hogs
The following are some of the signs of estrus in hogs:
- Swollen and red vulva
- Increased vocalization
- Rubbing against objects
- Standing still when a boar mounts her
- Mounting other sows
Breeding Hogs
The best time to breed a sow is 12-24 hours after she first shows signs of estrus. This is because ovulation, the release of an egg from the ovary, typically occurs 24-36 hours after the onset of estrus.
The sow should be introduced to the boar in a breeding pen. The boar and sow should be left together for 20-30 minutes. If the sow is receptive to breeding, the boar will mount her.
Pregnancy and Farrowing
The gestation period for hogs is 114-115 days. After farrowing, the sow will nurse her piglets for 4-6 weeks.
Managing the Estrus Cycle
There are a number of things that can be done to manage the estrus cycle in hogs. These include:
- Monitoring the sow’s vulva for signs of estrus
- Using heat detection boars
- Using boar pheromones
- Using artificial insemination
By managing the estrus cycle, you can improve the breeding efficiency of your hog operation.
I hope this guide has been helpful. If you have any questions, please feel free to ask.
