Genetic and economic benefits of selection based on performance recording and genotyping in lower tiers of multi-tiered sheep breeding schemes

Open nucleus systems (ONS) have been used in sheep breeding for a number of years, usually in group breeding schemes. In the simplest form the population is divided into two tiers, the nucleus flock composed of elite individuals, while the base, which forms the majority of the population, is usually sub-divided into a number of individual flocks. Animals born in the nucleus may be selected as replacements in the base, while superior animals born in the base may become part of the breeding population of the nucleus. The optimum structure and genetic benefits of using an ONS under Australasian conditions have been extensively studied using deterministic predictions (James, 1977; Mueller and James, 1983). However, subsequent advances in genetic evaluation (e.g. the application of Best Linear Unbiased Prediction (BLUP)) and the smaller flock sizes typical in Europe, are likely to impact on the outcome and optimum structure of such systems.

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Opportunities for breeding for disease resistance in British sheep

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200009601 ◽

2005 ◽

Vol 2005 ◽

pp. 49-49

Author(s):

G.J. Nieuwhof ◽

S.C. Bishop

Keyword(s):

Disease Resistance ◽

Disease Incidence ◽

Selection Index ◽

Economic Values ◽

Sheep Breeding ◽

Sheep Scab ◽

Internal Parasites ◽

Breeding Schemes

Recently, the costs of eight sheep diseases were calculated by Bennett and IJpelaar (2003). The highest annual costs were estimated for enzootic abortions in ewes (EAE) £20 M and toxoplasmosis £12M. In a survey among its members, the Moredun Foundation (1997) identified internal parasites (GI parasites), sheep scab and footrot as the most important sheep diseases, but these three diseases were not analysed by Bennett and IJpelaar (2003). The aim of this study is to estimate the benefits of reductions in the incidence or severity of these diseases, using the methodology of Bennett et al. (1999), and the benefits of reductions in disease incidence or severity. From this, marginal economic values for resistance are calculated and applied in selection index scenarios that mimic current sheep breeding schemes.

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Improving lamb performance from Welsh Mountain Sheep breeding groups

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200006050 ◽

2001 ◽

Vol 2001 ◽

pp. 223-223

Author(s):

B M L McLean ◽

O D Davies ◽

D E Evans

Keyword(s):

Performance Testing ◽

Cooperative Groups ◽

Sheep Breeding ◽

Local Type ◽

Group Breeding ◽

Working Together ◽

Breeding Schemes ◽

Carcass Conformation ◽

Breeding Groups ◽

Genetic Pool

Sheep group breeding schemes have gained in popularity in recent years. The objectives of group breeding schemes are to improve desirable traits such as carcass conformation, weight and maternal ability whilst maintaining local type. However, if group breeding schemes were to work together then a larger genetic pool of performance recorded animals would be available to facilitate improvements. The objectives of this project were therefore twofold, 1.) was to improve traits such as weight and carcass conformation and 2.) to demonstrate the benefits of cooperative groups working together. In this project, group breeding schemes from North and Mid Wales have been working together with ram performance testing groups from North, South and Mid Wales to improve results from Welsh Mountain breeding schemes.

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The Economic Benefits of the GED: A Research Synthesis: A NCSALL Research Brief

PsycEXTRA Dataset ◽

10.1037/e370742004-001 ◽

2013 ◽

Author(s):

John H. Tyler

Keyword(s):

Research Synthesis ◽

Economic Benefits

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Issues in college success: The economic benefits of academic and career preparation

PsycEXTRA Dataset ◽

10.1037/e424702008-001 ◽

2008 ◽

Keyword(s):

College Success ◽

Economic Benefits ◽

Career Preparation

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MARS — Its Tenth Anniversary of Operation and its Future

Methods of Information in Medicine ◽

10.1055/s-0038-1635276 ◽

1980 ◽

Vol 19 (03) ◽

pp. 125-132

Author(s):

G. S. Lodwick ◽

C. R. Wickizer ◽

E. Dickhaus

Keyword(s):

Conceptual Development ◽

Administrative Support ◽

Final Section ◽

Economic Benefits ◽

Hospital Environment ◽

Computer Scientist ◽

University Of Missouri ◽

Complete Bibliography ◽

The University ◽

Economic Considerations

The Missouri Automated Radiology System recently passed its tenth year of clinical operation at the University of Missouri. This article presents the views of a radiologist who has been instrumental in the conceptual development and administrative support of MARS for most of this period, an economist who evaluated MARS from 1972 to 1974 as part of her doctoral dissertation, and a computer scientist who has worked for two years in the development of a Standard MUMPS version of MARS. The first section provides a historical perspective. The second deals with economic considerations of the present MARS system, and suggests those improvements which offer the greatest economic benefits. The final section discusses the new approaches employed in the latest version of MARS, as well as areas for further application in the overall radiology and hospital environment. A complete bibliography on MARS is provided for further reading.

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Screening for the FV: Q506 Mutation – Evaluation of Thirteen Plasma-based Methods for their Diagnostic Efficacy in Comparison with DNA Analysis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1655984 ◽

1997 ◽

Vol 77 (03) ◽

pp. 436-439 ◽

Cited By ~ 39

Author(s):

Armando Tripodi ◽

Barbara Negri ◽

Rogier M Bertina ◽

Pier Mannuccio Mannucci

Keyword(s):

Venous Thrombosis ◽

Large Scale ◽

Dna Analysis ◽

Genetic Defect ◽

Laboratory Diagnosis ◽

Economic Benefits ◽

Factor V ◽

Factor X ◽

Diagnostic Efficacy ◽

Dna Test

SummaryThe factor V (FV) mutation Q506 that causes resistance to activated protein C (APC) is the genetic defect associated most frequently with venous thrombosis. The laboratory diagnosis can be made by DNA analysis or by clotting tests that measure the degree of prolongation of plasma clotting time upon addition of APC. Home-made and commercial methods are available but no comparative evaluation of their diagnostic efficacy has so far been reported. Eighty frozen coded plasma samples from carriers and non-carriers of the FV: Q506 mutation, diagnosed by DNA analysis, were sent to 8 experienced laboratories that were asked to analyze these samples in blind with their own APC resistance tests. The APTT methods were highly variable in their capacity to discriminate between carriers and non-carriers but this capacity increased dramatically when samples were diluted with FV-deficient plasma before analysis, bringing the sensitivity and specificity of these tests to 100%. The best discrimination was obtained with methods in which fibrin formation is triggered by the addition of activated factor X or Russell viper venom. In conclusion, this study provides evidence that some coagulation tests are able to distinguish carriers of the FV: Q506 mutation from non-carriers as well as the DNA test. They are inexpensive and easy to perform. Their use in large-scale clinical trials should be of help to determine the medical and economic benefits of screening healthy individuals for the mutation before they are exposed to such risk factors for venous thrombosis as surgery, pregnancy and oral contraceptives.

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