I have always taken the firm position that you should only breed cats once per year. I am still very much a firm believer of this, but recently I have had to really think about this. There are several reasons that I have felt this way, these are my views and in no way make someone else's breeding practices wrong (each breeder knows their cats best and they along with their vet will make the best choice for each particular cat).
It is my opinion that queens (female cats) should have time to get back into condition after a 2 month pregnancy followed by 8-12 weeks of nursing. The queens body needs to lose the "baby weight" and get back to their normal weight and muscle condition. They should be back to their normal daily routine of sleeping and playing. They should enjoy several months of being a spoiled pet before we ask their bodies to create babies again.
Now the reasons against waiting 1 year for breeding. The biggest concern is a medical issue called pyometra which is a uterine infection. There are 2 forms of a pyo-open and closed. Really what it comes down to is both forms are life threatening (the closed form more so). With each heat cycle you increase the risks. Many breeders feel that risk drastically increases if you let the queen have more than 4 heat cycles. The other concern is cystic ovaries which can cause a queen to become sterile. Of the two conditions a pyometra is scary and something no owner or breeder every wants to deal with. The 3rd concern is females who are coming in and out of heat lose weight and this can be a very drastic weight change.
Now the reason why I am righting this. I have stated here on this website and on the Emmers Facebook page that we will only breed our girls once per year but now we find ourselves in a pickle. Lilly had a litter of kittens on March 18, 2016 and if you haven't seen them check out our previous kittens gallery. Lilly came back from her pregnancy and nursing really fast. Unfortunately Mother Nature has had other plans and Lilly has had more heats than she usually does so we decided it would be healthier and in her best interest to breed her again.
Over the next couple weeks we will write blog posts about what is happening during the developmental stages of the kittens.