Cycles and Heat Determination. Pigs life cycle from lust love and death. When the pig is pressed hard with the hands on either side of her back she will stand still, showing she is ready to accept the male. This can be used to help synchronize farrowing dates in small herds so that animals are farrowing around the same time, and can be weaned of piglets (and therefore bred for their next litter) at the same time. Lutalyse or Prostamate) to induce the female to abort the litter. This “male effect” works best when young females are kept separate from the boar then the boar is introduced when the femails are 160-175 days old. Photo by Kaytee Norris and Emily McConnell. she is pregnant or not because you have to wait and repeat the breeding again. The oestrus period can last one to three days with ovulation often occurring late on the second day of ‘standing heat’. Signs of heat. Ovulation generally occurs 23 to 48 hours after the initiation of estrus. The rebreeding period of sows can be shortened by high feeding levels (flushing) and lengthened by stress (eg fighting when put into groups). The female pig coming into heat is restless and may not eat. When at peak oestrus they show the “stance reflex” by arching their back, stand rigidly when pushed from behind, and allow you to sit on their backs. In the days prior to standing heat the female may or may not present physical signals that heat is coming. One Boar is enough to give those 20 in heat female pigs pregnant. 21 day heat cycle Number of days your female pigs starts to feel horny or what they call heat, but varies from 17 to 25 days before it begins to feel wanting a lover again (heat). But they can be mated at their second heat if intensive production is the objective. This periodic exposure assures that heat responses occur during manager observation and not when you are away from the pigs. Sniffing genital area and riding pen mates. The first sign of a sow or gilt coming into heat is a red, swollen vulva. Most gilts (young females) show their first oestrus between 170-220 days old, which is usually around 90kg liveweight. Swine estrous cycle The estrous cycle in the pig averages 21 days but can range from 17 to 25 days. And Imagine the sows right after 40 days they are again ready for another battle. The pork industry is in dire need of stockmanship skills that will enhance heat detection and mating in the breeding herd. Females cycle at intervals of about 21 days (range18-24). Old Age. A good commercial target is 1.5 litters/year. the Estrous Cycle is 21 days. Mucous discharge from vulva. However, a single mating at the correct time is better than multiple matings at the wrong time. Heat detection and breeding timing are very important. The sow will be in heat for 8 to 36 hours. Gilts after their first litter will return to heat a few days later than older sows that have had many litters. The Pennsylvania State University, 323 Agricultural Administration Building, University Park, PA 16802, Swine Production and Management Home Study Course. The first day of standing heat, when the female is receptive to the male and will stand to be mounted, is referred to as day 0. An average animal in heat today will be in heat again in three weeks. Having an active, mature boar to help with heat checking is the best way to determine standing heat, but is not possible at every farm, especially when Artificial Insemination (AI) is practiced. Fetal Pig Dissection Humans and fetal pigs share very similar anatomy as they are both mammals. Get all the latest news along with practical tips and expert advice.