Researchers quickly realized that genetic factors created variation among animals making it difficult to test the hypotheses. For many experimental circumstances, it is critical in research to have as much uniformity as feasible. Inbreeding has a significant impact on a population's genetic makeup, and under the right circumstances, it may result in the development of inbred strains in which all individuals are genetically similar at nearly all loci. Inbreeding splits a population into subpopulation and responsible for unwanted genetic drift. The response to inbreeding depression varies between traits, wherein traits that involve fitness, such as litter size or lactation in mammals are the ones critically affected. Outcross usually changes the mean and increases the genetic variance of the resulting population. Combinations of inbreeding and selection systems give geneticists a wide variety of methods for controlling the inherited characteristics of research. Hybrid animals are genetically identical to each other; however, they carry alleles from each parent and are heterozygous for any gene where the parents differ. The direct approach for calculating inbreeding coefficient requires accurate pedigree information extending back at least three to four generations. Such detailed long-term observations are available for only a handful of populations in a few species. As a result, heterozygosity at a panel of neutral genetic markers might theoretically be used to determine ‘F'. In fact, if a large number of genetic markers are available, heterozygosity may offer a more accurate approximation of real inbreeding than pedigree data spanning only a few generations. The book entitled “Genetic Characterization of Fitness Traits” authored by “Shweta Sachan” has been designed to meet the needs of the research scholars, teachers, and scientists associated with Animal Genetics and Breeding. The work described in this book is the research work of Ph.D. dissertation entitled “Genetic Characterization and Expression Profiling of Genes Related to Fitness Traits in Inbred and Outbred Swiss Albino Mice”. The content in the book represents an attempt to summarize and consolidate a considerable amount of information related to the genetic characterization and expression of genes related to fitness traits.
Shweta Sachan Animal Genetics and Breeding ICAR-Indian VeterinaryResearch Institute Izatnagar-243 122 (U.P.), India
1. Introduction........................................................................................ 1
2. Review of Literature ......................................................................... 7
3. Materials and Methods................................................................... 49
4. Results ................................................................................................ 71
5. Discussion .......................................................................................127
6. Summary and Conclusions .........................................................149
References .......................................................................................161
