Breeding father-daughter dogs has seen a rise in infertility. This is because these inbred dogs lack gene variation, which is the difference in the DNA sequence in their genomes.
Since the mother and father share the same genes, reports indicate that male inbred puppies have lower fertility rates than purebreds.
The females also suffer from dystocia, a condition where they undergo difficult or abnormal labor. Dystocia in inbred females takes place when the litter has congenital disabilities or is larger than regular-sized uterine puppies. This condition complicates dog pregnancy, and these females often deliver via C-section.
Limits the gene pool
A gene pool is the genetic diversity found in a population at a given time. Animals with a large gene pool have extensive genetic diversity. They can withstand the challenges and stresses posed by their environmental conditions. The large gene pool creates room for growth and variety throughout the generations.
Inbred dogs, however, do not enjoy this. On the contrary, they have a small gene pool, which makes the species prone to extinction when faced with environmental stresses. Close inbreeding damages the potential for the gene pool to expand and makes the generational lines more susceptible to genetic disorders.
Congenital disabilities are functional or structural anomalies that develop during intrauterine life. Breeding a father dog to a daughter may pass on undesirable and abnormal genes to the litter. How?
With inbreeding, it is more likely that the recessive genes will be more prevalent in the offspring. This is because both the father and mother share a similar set of alleles in their genes.
For this reason, it is not uncommon to see inbred puppies with eye disorders, abnormal bodies and faces, cancer, systemic disorders, and skeletal deformities.
Unfortunately, some congenital disabilities are visible after birth. Some owners report raising a healthy dog until it becomes severely sick later, only to realize they have an existing congenital disability.
To better understand how inbreeding causes health problems, take the Cavalier King Charles as an example. This breed is prone to heart problems. In fact, most Cavalier King Charles dogs die from mitral valve disease (MVD).
So, assume you inbreed this type of dog. Both the father and the mother are susceptible to MVD, and this condition will be heightened in their offspring. The results? A sickly litter with a high mortality rate.
In addition, inbred dogs tend to display abnormal behavioral issues. For instance, they lack affection, are more anxious and impulsive and have higher aggression and irritation levels. They may also be fearful compared to purebred dogs and be less intelligent.