tailieunhanh - Báo cáo sinh học: "The nature, scope and impact of genomic prediction in beef cattle in the United States"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học quốc tế đề tài: The nature, scope and impact of genomic prediction in beef cattle in the United States | Garrick Genetics Selection Evolution 2011 43 17 http content 43 1 17 Ge n et i cs Selection Evolution REVIEW Open Access The nature scope and impact of genomic prediction in beef cattle in the United States Dorian J Garrick1 2 Abstract Artificial selection has proven to be effective at altering the performance of animal production systems. Nevertheless selection based on assessment of the genetic superiority of candidates is suboptimal as a result of errors in the prediction of genetic merit. Conventional breeding programs may extend phenotypic measurements on selection candidates to include correlated indicator traits or delay selection decisions well beyond puberty so that phenotypic performance can be observed on progeny or other relatives. Extending the generation interval to increase the accuracy of selection reduces annual rates of gain compared to accurate selection and use of parents of the next generation at the immediate time they reach breeding age. Genomic prediction aims at reducing prediction errors at breeding age by exploiting information on the transmission of chromosome fragments from parents to selection candidates in conjunction with knowledge on the value of every chromosome fragment. For genomic prediction to influence beef cattle breeding programs and the rate or cost of genetic gains training analyses must be undertaken and genomic prediction tools made available for breeders and other industry stakeholders. This paper reviews the nature or kind of studies currently underway the scope or extent of some of those studies and comments on the likely predictive value of genomic information for beef cattle improvement. Background Genetic improvement results from selection of aboveaverage candidates as parents of the next generation. In a competitive market above-average candidates would be those that improve consumer satisfaction influencing immediate eating quality purchase cost long-term health implications of consumption care