Good breeding practice is based on
selectively breeding into reputable bloodlines
which are, as far as possible, free from disease and defects.
In-breeding is not desirable, or necessary these days, as there is a wide gene-pool to choose from, but in the early days in-breeding was practiced as there were so few pedigree cavaliers available. If this practise had not been carried out, the development of the Cavalier would have taken much longer.
Old wives tales like “having a litter will cure False pregnancies” and “a litter is good for the bitch and prevents pyrometra” are totally false. As responsible breeders, we only breed once each year, from the bitch’s second or third season, up to 5 years old, and then our bitches are spayed. Spaying is the only reliable way of stopping false pregnancies and curing pyrometra.