Accurately estimating inbreeding is important because inbreeding reduces fitness and production traits in populations. We analyzed information from pedigrees and from microsatellite markers to estimate inbreeding in a line of Japanese quail derived from a randombred line (QO) and maintained for 17 generations by pedigreed matings of brothers to groups of sisters. Pedigree data were used to calc...

Stressful environments are often said to increase the expression of inbreeding depression. Alternatively, Crow's "opportunity for selection" (the squared phenotypic coefficient of variation) sets a limit to how much selection can occur, constraining the magnitude of inbreeding depression. To test these hypotheses, we planted self- and cross-fertilized seeds of Brassica rapa into a factorial exp...

We studied three closely related species of endangered gazelles (Gazella dorcas, Gazella dama and Gazella cuvieri) with different levels of inbreeding in order to determine at which intensities inbreeding influences ejaculate traits. We also examined whether fluctuating asymmetry (FA) is a reliable indicator of genetic as well as reproductive stress. Our results show that, within each populatio...

Inbreeding is the mating of relatives that produce progeny having more homozygous alleles than non-inbred animals. Inbreeding increases numbers of recessive alleles, which is often associated with decreased performance known as inbreeding depression. The magnitude of inbreeding depression depends on the level of inbreeding in the animal. Level of inbreeding is expressed by the inbreeding coeffi...

effects of inbreeding coefficient on estimates of genetic parameters, breeding values and genetic trends for production traits (milk, fat and protein yields), reproduction traits (age at the first calving, interval between first insemination to conception, calving interval, interval between calving to first insemination, and calving ease) as well as longevity of holstein cattle in iran were stu...

OBJECTIVE To examine mechanisms by which consanguinity might increase the risk of type 2 diabetes (T2D) in a Saudi population. METHODOLOGY 362 adult male participants were recruited, 179 were T2D patients and 183 healthy siblings. T2D severity was assessed in patients by recording age at diagnosis. In healthy subjects, diabetes risk was studied by measuring the body mass index, fasting blood ...

Some of the methods of estimation of allele frequencies and inbreeding coefficients in a K-allele model are examined. A result that has long been assumed to be true is proved. That is, in the presence of inbreeding, the maximum likelihood estimators of the allele frequencies and of the inbreeding coefficient f do not in general equal their observed (or sample) values (except when K 1⁄4 2). A le...

Effects of inbreeding on individual fitness are of long-standing interest in evolutionary biology and conservation studies. Since estimation of the inbreeding coefficient of a given individual is often impossible in wild populations, some authors have attempted to demonstrate inbreeding depression in such populations by correlating the multi-locus marker heterozygosity of individuals with a tra...

The difficulty of obtaining pedigrees for wild populations has hampered the possibility of demonstrating inbreeding depression in nature. In a small, naturally restored, wild population of grey wolves in Scandinavia, founded in 1983, we constructed a pedigree for 24 of the 28 breeding pairs established in the period 1983-2002. Ancestry for the breeding animals was determined through a combinati...

Self-fertilization and crossing were combined to produce a large number of levels of inbreeding and of degrees of kinship. The inbreeding effect increases with the complexity of the character and with its supposed relationship with fitness. A certain amount of heterozygosity appears to be necessary for the expression of variability. With crossing of unrelated noninbred plants, genetic variance ...