AST and JONES (1919) and CASTLE (1930) reviewed the significant experiE ments with plants and laboratory animals that contributed to the formulation of the modern viewpoints concerning the effects of inbreeding. The phenomena associated with inbreeding: decline in vigor, increased uniformity within the inbred stock, increased prepotency in outside crosses, isolation of abnormal types, etc., wer...

Understanding the fitness consequences of inbreeding (inbreeding depression) is of importance to evolutionary and conservation biology. There is ample evidence for inbreeding depression in captivity, and data from wild populations are accumulating. However, we still lack a good quantitative understanding of inbreeding depression and what influences its magnitude in natural populations. Specific...

One key objective in evolutionary ecology is to understand the magnitude of inbreeding depression expressed across sex-specific components of fitness. One major component of male fitness is fertilization success, which depends on male gametic performance (sperm and pollen performance in animals and plants, respectively). Inbreeding depression in male gametic performance could create sex-specifi...

Inbreeding depression is assumed to be a central factor contributing to the stability of plant mating systems. Predicting the fitness consequence of inbreeding in natural populations is complicated, however, because it may be affected by the mating histories of populations generating variation in the amount of purging of deleterious alleles. Furthermore, the level of inbreeding depression may d...

Inbreeding coefficients are calculated routinely for all animals included in national genetic evaluations for yield traits. The base population for inbreeding is defined as animals born during 1960. Animals with unknown parents are assumed to have inbreeding coefficients that are equal to the mean of coefficients for animals with known parents born during the same year. Mean inbreeding coeffici...

Inbreeding depression is the reduction in fitness in offspring resulting from mating individuals that share at least one common ancestor. The objective was to compare the effect of genome-wide and location specific homozygosity on fertility and milk production traits in dairy cattle. Pedigree inbreeding was compared with genomic inbreeding which is the realised proportion of the genome that is ...

THE EFFECT OF INBREEDING ON SOCIALITY IS STUDIED THEORETICALLY FOR THE EVOLUTION OF INTERACTIONS BETWEEN SIBLINGS IN CERTAIN MIXED MATING SYSTEMS THAT GIVE RISE TO INBREEDING: sib with random mating and selfing with random mating. Two approaches are taken. First, specific models of altruism are studied for the various mating systems. In the case of the additive model, inbreeding facilitates the...

The objective of this research was to estimate the amount of inbreeding and effective population size of the Japanese Black breed using pedigree records from bulls and heifers registered between 1985 and 1997. Inbreeding was quantified by three F-statistics: actual inbreeding, inbreeding expected under random mating, and inbreeding due to population subdivision. During the period of 1985 to 199...

There is ample evidence for inbreeding depression manifested as a reduction in fitness or fitness-related traits in the focal individual. In many organisms, fitness is not only affected by genes carried by the individual, but also by genes carried by their parents, for example if receiving parental care. While maternal effects have been described in many systems, the extent to which inbreeding ...

It is often assumed that inbreeding reduces resistance to pathogens, yet there are few experimental tests of this idea in vertebrates, and no tests for the effects of moderate levels of inbreeding more commonly found in nature. We mated wild-derived mice with siblings or first cousins and compared the resistance of their offspring to Salmonella infection with outbred controls under laboratory a...