Besides Valentine's day, on the homestead, love is in the air. February is breeding time for many animals in order to have spring babies. It is a great month for breeding pigs in MN because their litter will be due (3 months, 3 weeks, 3 days) from estrous, or from the day of her heat cycle. Pigs typically cycle every 18-21 days. Gilts being closer to 18 days and sows on day 21. I currently have 5 females: 3 Mangalitsas, 1 Berkshire, and 1 Tamworth. The Berkshire and two mangalitsas are gilts (one year old never been bred).
Since the time I started homesteading, I have planned to AI, artificial inseminate my pigs. Cuts down on cost to feed a boar, the time to separate him from the group, and to selectively breed with other breeds and pedigrees. Often boars can become aggressive and since I have little farmers in training, I don't have time for that non-sense.
I had figured my Tamworth would be in heat Monday February 16 so I overnighted Tamworth boar semen from International Boar Semen out of Iowa. They put a seven day extender in the semen in hopes you catch them on one of those days and includes time for shipping. The cost to overnight is $67 and $30 a tube of Tamworth semen, but worth it so I didn't have to wait another 21 days. I bought 2 tubes of semen because your chances are best to breed before and after estrous. If she was bred on Feb 16, the she would have her litter aprox on June 10th. Next year, I will be breeding end of January to ensure May litters so I can get at least two breedings out of the sows, hopefully three. 
My husband fed the pigs in the morning, so I could check them for standing heat after they were done with that distraction. Standing heat means they will stand VERY still to be bred when pushing on their backs which is one of the main signs she is ready for a boar. Boars know females are ready by scent/pheromones. I however am not a boar so need to read her several signs differently - pushing on their backs, looking for affection or aggression, watching them to see if they mount other pigs etc. A Minnesota February is typically quite cold and sometimes this is difficult to read with pigs in such weather. Tammy, the Tamworth should have been ready given my documenting but when I looked at her Monday morning, she did not appear to be. She looked more relaxed than ever. In the past, when she is full blown heat cycle, she's a little scary. She's about 450 lbs, red and wants her some affection! This was not the case this morning. Frustrated that I must have missed her cycle by a day or two, I noticed the Berkshire gilt to have a red and swollen vulva- another tell tale sign of a gilt being in heat. The gilts are about 50/50 with the standing heat trick. They have no idea what they are supposed to do and don't have any idea about a boar yet so they often will just walk around being affectionate to other pigs and trying to nibble or bite. In a quick decision to use the viable Tamworth semen, I decided to AI my Berkshire instead. Otherwise it would be a waste if I didn't get the heat cycle dead on with the Tamworth. I am certain she was not ready given the apparent signs in the past. Olivia is the Berkshire, and normally she's a bit of a head case, VERY noisy, jumps all over the place and annoys the crazy out of you when I'm working in the pen. She was not at all this morning. Very calm, not skidderish at all. She was ready. 
I had read last year that Berkshire Tamworth crosses produce some of the best bacon and pork available and are very hard to find as feeder pigs. Both have very long bodies but Tamworth's are taller than Berks so it is probable for the mix to produce more meat. Plus with bodies that long, imagine the BACON! 
It's going to be very exciting to see if I get litters out of my sows/gilts. Birth in general is exciting, but piglets are super fun!
This is me, artificially inseminating my Berkshire, Olivia. Hopefully we get spring piglets!!!