the purpose of this study was to investigate the effect of maternal inbreeding on incidence of twinning,dystocia and stillbirth in holstein cows of iran. calving records from march 2000 to april 2009 comprisingof 365,021 calvings on 153,802 cows from 86 dairy herds were used. the mean level of inbreeding was0.7%, less than 37% of all animals were inbred, and a small proportion (3.45%) of inbree...

Many linkage studies are performed in inbred populations, either small isolated populations or large populations with a long tradition of marriages between relatives. In such populations, there exist very complex genealogies with unknown loops. Therefore, the true inbreeding coefficient of an individual is often unknown. Good estimators of the inbreeding coefficient (f) are important, since it ...

Genetic and Phenotypic Effects Inbreeding can have dramatic effects on a herd. These effects are the result of individuals receiving identical genes from each parent. If the parents are related, it is more likely that they have genes that are identical. An individual receiving identical genes from each parent is said to be homozygous for that pair of genes. This would be desirable if the gene t...

Synergistic epistasis for fitness is often assumed in models of how selection acts on the frequency and distribution of deleterious mutations. Evidence for synergistic epistasis would exist if the logarithm of fitness declines more quickly with number of deleterious mutations, than predicted by a linear decline. This can be studied indirectly by quantifying the effect of different levels of inb...

Consanguinity is an important problem in medical genetics because it significantly influences morbidity risks for recessive disorders. Genetic counsellors manage this problem in very simple terms according to Mendelian rules but without considering the theory of inbreeding in full. Consequently, the severity of specific recessive genetic risks is not accurately estimated. The purpose of this pa...

background: although numerous studies have found deleterious effects of inbreeding on childhood and pre-reproductive mortality, one question remains inadequately addressed: dose inbreeding lead to increased childhood mortality rates in countries with high level of consanguinity? methods: to evaluate the public health impact of inbreeding on offspring mortality, the association between mean of i...

Sexually selected traits are expected to evolve to a point where their positive effect on reproductive success is counterbalanced by their negative effect on survival. At the genetic level, such a trade-off implies antagonistic pleiotropy between survival and the expression of sexually selected traits. Yet, the consequences of such a genetic architecture have been largely overlooked in studies ...

Additive, dominance, and additive by additive components of genetic variance and inbreeding depression were estimated for production traits from a group of daughters of young sires from the Canadian Holstein population. First lactations of 92,838 cows were analyzed. Three sire and dam models (additive, additive plus dominance, additive plus dominance plus additive by additive genetic effects), ...

This study aimed to examine the effects of inbreeding on 12 quantitative phenotypes like body weight, height, sitting height, head circumference, head length, head breadth, chest circumference, verbal, performance and full scale intelligence quotients, systolic and diastolic blood pressures among North Indian Children. The sample consisted of 3,253 subjects (1,683 males and 1,570 females) inclu...

The extent to which inbreeding depression affects longevity and patterns of survivorship is an important issue from several research perspectives, including evolutionary biology, conservation biology, and the genetic analysis of quantitative traits. However, few previous inbreeding depression studies have considered longevity as a focal life-history trait. We maintained laboratory populations o...