Computation of inbreeding rate (DeltaF) must consider that inbreeding is delayed with one generation with respect to the idealized population when addressed using individual inbreeding coefficients. The expression relating inbreeding in generation t with inbreeding rate F(t) = 1 - (1-DeltaF)(t) should be more correctly written in real animal populations as F(t) = 1 - (1-DeltaF)(t-1), as changes...

The objective of this study was to quantify the effect of inbreeding on carcass quality, growth rate, live conformation measures, and calving performance in purebred populations of Charolais, Limousin, Simmental, Hereford, and Angus beef cattle using data from Irish commercial and pedigree herds. Variables analyzed are reflective of commercial farming practices. Inbreeding was included in a lin...

Inbreeding is usually defined as the mating between relatives and the progeny that result of a consanguineous mating between two related individuals is said to be inbred (CavalliSforza & Bodmer, 1971; Hedrick, 2005; Vogel & Motulsky, 1997). As a result of inheriting the same chromosomal segment through both parents, who inherited it from a common ancestor, the individuals born of consanguineous...

Continuous inbreeding exposes deleterious recessive alleles to selection and can thereby lead to partial purging of the genetic load and reduced inbreeding depression. Purging has been well documented in experimental laboratory populations, but evidence of reduced inbreeding depression due to purging in wild populations is largely lacking. This study examines the inbreeding load associated with...

Inbreeding is known to have adverse effects on fitness-related traits in a range of insect species. A series of theoretical and experimental studies have suggested that polyandrous insects could avoid the cost of inbreeding via pre-copulatory mate choice and/or post-copulatory mechanisms. We looked for evidence of pre-copulatory inbreeding avoidance using female mate preference trials, in which...

Attempts to conserve threatened species by establishing new populations via reintroduction are controversial. Theory predicts that genetic bottlenecks result in increased mating between relatives and inbreeding depression. However, few studies of wild sourced reintroductions have carefully examined these genetic consequences. Our study assesses inbreeding and inbreeding depression in a free-liv...

Background: Interactions between inbreeding and maternal effects have received little attention, and the effect of maternal age on inbreeding depression in offspring has been almost entirely neglected. Maternal age affects allocation of resources and other materials to offspring, which can affect the fitness consequences of inbreeding. An interaction between inbreeding and maternal age thus has...

The widespread consensus among biologists is that, with a few exceptions, inbreeding leads to a loss of biological fitness. Animals in an inbred lineage are less likely to survive and less likely to reproduce than animals in more outbred lineages. This has been demonstrated many times in well-studied, naturally outbreeding species. Inbreeding can result in reduced fertility both in litter size ...

Relationships between pedigree coefficients of inbreeding and molecular metrics are generally weak, suggesting that measures of heterozygosity estimated using microsatellites may be poor surrogates of genome-wide inbreeding. We compare three endangered species of gazelles (Gazella) with different degrees of threat in their natural habitats, for which captive breeding programmes exist. For G. do...

Inbreeding is defined as half of the genetic relationship between an animal’s parents. For example, the offspring from a mating of animals A and B, which have the same father, will have 12.5 percent inbreeding, because the genetic relationship between A and B is 25 percent. Statistical methods to select the best sires of each generation have been developed, making it feasible to achieve any pos...