Inbreeding depression causes reduced fecundity in Golden Retrievers

Abstract

Inbreeding depression has been demonstrated to impact vital rates, productivity, and performance in many domestic species. Many in the field have demonstrated the value of genomic measures of inbreeding compared to pedigree-based estimates of inbreeding; further, standardized, high-quality phenotype data on all individuals is invaluable for longitudinal analyses of a study cohort. We compared measures of reproductive fitness in a small cohort of Golden Retrievers enrolled in the Golden Retriever Lifetime Study (GRLS) to a genomic measurement of inbreeding, FROH. We demonstrate a statistically significant negative correlation between fecundity and FROH.This work sets the stage for larger scale analyses to investigate genomic regions associated with fecundity and other measures of fitness.

High retention of genomic variation and fitness-related traits in the effective population of reintroduced wolves in Yellowstone National Park

“…Similar patterns of reproductive consequences were found with maternal inbreeding levels in red deer ( Cervus elaphus ) being correlated with reduced offspring survival, further suggesting that depression of fitness traits in adult individuals is likely to be more accurately estimated from marker-based data (Huisman et al 2016). Chu and colleagues (2019) reported a negative correlation between fecundity and autozygosity in a longitudinal study of domestic dogs, which also supported pedigree-based assessments of such (LeRoy et al 2015).…”

The effect of inbreeding, body size and morphology on health in dog breeds

“…A demonstration of direct negative effects of inbreeding within breeds has been limited, likely due to the need to use molecular tools to determine actual historic inbreeding, the absence of dogs with low inbreeding (< 0.1) or no inbreeding and the challenges of phenotyping for individual animals. Inbreeding (range 0.2-0.48) based on runs of homozygosity was associated with smaller litters in Golden retrievers [49]. Inbreeding in dams (0.32-0.45) was associated with fertility in the Entlebucher Mountain dog [50].…”

Canine fertility: The consequences of selection for special traits

“…Estimation of inbreeding can be really effective and accurate using genomic tools like SNPs and whole genome sequencing (WGS). The genomic inbreeding based on runs of homozygosity ( F ROH ), a direct measurement of continuous homozygous segments of DNA sequence, is a very effective tool because it evaluates the fraction of the genome represented by homozygous DNA stretches identical by descent (Chu et al, ). Genomic inbreeding has been recently considered in a paper about inbreeding depression in Golden Retrievers: a negative correlation between F ROH and fecundity has been described (Chu et al, ).…”

“…Companion animals’ registries are very often influenced by the so‐called ‘popular sire’ effect which create an artificial bottleneck in the breed population strongly affecting genetic variability in the next generations. FCI (Federation Cinologique International) and AKC (American Kennel Club), the most important kennel clubs in the world as number of purebred puppies entered per year, already defined the monitoring and control protocols for inbreeding levels in the different registered breeds (Chu et al, ). The genetic control level of a trait is described by the heritability ( h 2 ) which defines the proportion of the genetic variance on the total observed phenotypic variance.…”