Some articles and resources on genetic diversity and population genetics for those interested:

Canine fertility: The consequences of selection for special traits. January, 2020. (Pay for full text)

Inbreeding depression causes reduced fecundity in Golden Retrievers. 2019.

Boosting genetic diversity may save vanishing animal populations. But it may also backfire. 2019.

Pedigree data indicate rapid inbreeding and loss of genetic diversity within populations of native, traditional dog breeds of conservation concern. 2018.

Fine-Scale Resolution of Runs of Homozygosity Reveal Patterns of Inbreeding and Substantial Overlap with Recessive Disease Genotypes in Domestic Dogs. 2018.

Whole-genome sequence, SNP chips and pedigree structure: building demographic profiles in domestic dog breeds to optimize genetic-trait mapping. 2016.

Trends in genetic diversity for all Kennel Club registered pedigree dog breeds. 2015.

Population Structure and Inbreeding From Pedigree Analysis of Purebred Dogs. 2008.