Many brachycephalic dog breeds have great difficulty giving birth due to their physical characteristics. British, French and pug bulldogs are deliberately selected for having a large head, broad shoulders and a narrow pelvis, which means that the puppy's head and shoulders are too large to pass through the mother's pelvic canal. This has resulted in short legs, a compact body and narrow hips, making it impossible for French Bulldogs to reproduce on their own. Dogs have respiratory, skeletal and skin problems, and what's worse, many are unable to mate or give birth naturally.
To ensure that high-risk breeds, such as the English bulldog, do not continue to suffer unnecessarily, it is necessary to review breed regulations and take fully into account other approaches, such as external crossing. In addition, the researchers found a worrying lack of diversity in the region of the genome that regulates dogs' immune systems. The breed is also known for the lack of maternal instincts around its puppies (which may be because they don't take into account the natural birth process). If you want to become a breeder of French Bulldogs, the process is actually much more complex than locking them together in a room and letting nature take its course.
For Adam Boyko, a geneticist at the School of Veterinary Medicine at Cornell University, the new research shows a classic story about dog breeding. The researchers collected and analyzed the DNA of 139 bulldogs, including a control group of healthy puppies living in North America, Europe and Argentina and another group of dogs admitted to the veterinary hospital of the University of California at Davis for various ailments. Breeding for flat faces has caused an extreme form of brachycephaly, a shortening of the skull that is now the leading cause of death for bulldogs. It is a matter of great concern that many of these dogs cannot give birth without surgery and have to endure the anguish and suffering that this entails.
Dogs that undergo C-sections are more likely to have problems giving birth naturally when they have later layers. Bulldogs seem relaxed and sweet when you meet them in passing. However, they can't regulate their temperature by panting as well as other dogs do, and even normal activities in intense heat conditions can cause heat stroke. In a healthy and diverse population, each individual would be expected to have a very different genomic structure, but in the case of bulldogs, large regions of the genome were the same in all the individuals sampled.
This lack of genes represents an enormous challenge for breeders who want to naturally reintroduce healthier traits into the population.