1,328 research outputs found
Breeding for Resistance to Infectious Diseases in Small Ruminants
No full textLivestock Production/Industries,
Resistance to endoparasites in small ruminants: Genetic considerations
No full textThis paper focusses on within-breed genetic variation in resistance to endoparasites in the Australian Merino. It stresses possible differences in the Merino resistance, simply because of different history of management. The Australian Merino was introduced into Australia 200 years ago. It has almost entirely developed in that environment, i.e., it has been exposed to different methods of parasite control drenching, and there has been very little natural selection for resistance in this breed over recent years. However, the Australian Merino has been studied for over 20 years for genetic variation in parasite resistance. Genetic variation in resistance to endoparasites has been studied in five flocks in Armidale, and on flocks in New Zealand and Fiji. They were assessed using faecal egg count following artificial infection. The first flock includes lines of medium-wool peppins, and the others are based on fine and fine-medium Merinos. The work with these flocks showed that the heritability of resistance to endoparasites is measurable and that resistance is not genetically correlated with such production traits as fertility, body weight, fibre diameter and wool weight
Prospects of breeding small ruminants for resistance to internal parasites
No full textResistance to nematode parasites can be improved by selection, but efforts to include appropriate traits in commercial livestock breeding programs are only a recent development. Procedures for including resistance in breeding programs are similar to those involving other traits. The steps are described with special reference to sheep, and areas are highlighted where particular considerations exist. Three approaches are described and contrasted: breeding for resistance (reduced parasite numbers, as determined by faecal worm egg count); resilience (production during parasitism); or number of treatments required during parasitism. It is necessary, but difficult, to assess the economic benefits of improving resistance relative to other traits. Disease costs vary widely depending on the prevalence of the disease and on the availability, effectiveness and sustainability of alternative control measures. Costs of treatment and control are relatively simple to estimate for a given situation, but production losses are more difficult. Methods of dealing with this problem are discussed. Breeding for disease resistance usually requires that either selection candidates, or their relatives, are exposed to the pathogen so that resistance levels can be compared. Parasitic diseases generally create no special ethical problems in a breeding program unless natural challenge levels are insufficient to enable discrimination between hosts in their susceptibility. In the longer term, it is desirable that selection criteria for all major diseases be developed that will be informative in healthy animals. Molecular genetic markers offer promise, but simple genetic markers have so far been as elusive as physiological traits to predict resistance in undiseased animals. In the longer term, useful genetic markers will be found and techniques for combining these with phenotypic information need to be developed. Commercial breeding programes for sheep which include resistance to gastrointestinal roundworms are now operating in Australia and New Zealand, and issues related to breeding in the tropics are discussed
What is the Time Limit for Filing a Lawsuit? It Depends on What Your Definition of Arising Under Is! An Analysis of Jones v. R.R. Donnelley & Sons Co.
No full textThis article previews the Supreme Court case Jones et. al. v. R.R. Donnelly & Sons Co., 541 U.S. 369 (2004). The author predicted that the case would require the court to determine the appropriate statute of limitations to apply in a class action race-discrimination lawsuit filed under 42 U.S.C. § 1981
Dynamic synchromodal transport planning under uncertainty: A reinforcement learning approach
No full textAccepted Author ManuscriptTransport Engineering and Logistic
The Scope of Employer Liability for Employee Exposure to a Hazardous Substance: No Harm, No Foul? An Analysis of Metro-North Commuter R.R. Co. v. Buckley
No full textThis article previews the Supreme Court case Metro-North Commuter R.R. Co. v. Buckley, 521 U.S. 424 (1997). The author expected the Court to decide whether a railroad worker who is covered by the Federal Employer\u27s Liability Act who has been exposed to asbestos because of employer negligence but who has not developed an asbestos-related disease can recover damages for emotional distress caused by the exposure
Sheep Updates 2006 - part 2
No full textThis session covers six papers from different authors:
GENETICS
1. Novel selection traits - what are the possible side effects?, Darryl Smith, Kathryn Kemper, South Australian Research and Development Institute, David Rutley, University of Adelaide.
2. Genetic Changes in the Australian Merino since 1900, Sheep Genetics Australia Technical Committee, R.R. Woolaston Pullenvale, Queensland, D.J. Brown, Animal Genetics and Breeding Unit*, University of New England, K.D. Atkins, A.E. Casey, NSW Department of Primary Industries, A.J. Ball, Meat and Livestock Australia, University of New England
3. Influence of Sire Growth Estimated Breeding Value (EBV0 on Progeny Growth, David Hopkins, David Stanley, Leonie Martin, NSW Department Primary Industries, Centre for Sheep Meat Development, Arthur Gilmour, Remy van de Ven, NSW Department Primary Industries, Orange Agricultural Institute
FINISHING
4. Predicting Input Sensitivity on Lamb Feedlot Profitability by Using Feedlot Calculator, David Stanley, NSW Department Primary Industries, Centre for Sheep Meat Development, Geoff Duddy, NSW Department Primary Industries, Yanco Agricultural Institute, Steve Semple, NSW Department Primary Industries, Orange Agricultural Institute, David Hopkins, NSW Department Primary Industries, Centre for Sheep Meat Development
5. Annual ryegrass toxicity (ARGT) in WA - 2006, David Kessell, Meat & Livestock Australia ARGT Project, Northam, WA
6. Poor ewe nutrition during pregnancy increases fatness of their progeny, Andrew Thompson, Department of Primary Industries, Victori
Multi-agent model predictive control for transportation networks: Serial versus parallel schemes
No full textWe consider the control of large-scale transportation networks, like road traffic networks, power distribution networks, water distribution networks, etc. Control of these networks is often not possible from a single point by a single intelligent control agent; instead control has to be performed using multiple intelligent agents. We consider multi-agent control schemes in which each agent employs a model-based predictive control approach. Coordination between the agents is used to improve decision making. This coordination can be in the form of parallel or serial schemes. We propose a novel serial coordination scheme based on Lagrange theory and compare this with an existing parallel scheme. Experiments by means of simulations on a particular type of transportation network, viz., an electric power network, illustrate the performance of both schemes. It is shown that the serial scheme has preferable properties compared to the parallel scheme in terms of the convergence speed and the quality of the solution. If you want to cite this report, please use the following reference instead: R.R. Negenborn, B. De Schutter, and J. Hellendoorn, “Multi-agent model predictive control for transportation networks: Serial versus parallel schemes,” Engineering Applications of Artificial Intelligence, vol. 21, no. 3, pp. 353–366, Apr. 2008.Delft Center for Systems and ControlMechanical, Maritime and Materials Engineerin
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