|
|
|
| Registros recuperados: 16 | |
|
| |
|
| |
|
| |
|
|
| Stott, Alistair W.; Vosough Ahmadi, Bouda; Morgan-Davies, Claire; Dwyer, Cathy M.; Goddard, Pete; Phillips, Kate; Milne, Catherine E.; Kupiec-Teahan, Beata; Ringrose, Sian; Waterhouse, Tony. |
| Data from each of 5 commercial, extensive sheep farms in Cumbria, UK were used as parameters in a linear program (LP) representing labour and grazing management in such farming systems. The LP maximised ewe enterprise gross margin subject to constraints dictated by the labour availability and land types on each farm. Under the assumptions used, labour availability and price restricted ewe numbers well below those observed in practice on 2 farms i.e. land resources were adequate for the farming system practiced. On two other farms stocking levels and hence returns were limited by the availability of forage and hence feed input prices relative to output. On one farm, greater grassland productivity was the key determinant of system performance. It was... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Livestock Production/Industries; Extensive; Sheep; Economics; LP. |
| Ano: 2009 |
URL: http://purl.umn.edu/61123 |
| |
|
|
| Stott, Alistair W.; Milne, Catherine E.; Gunn, George J.. |
| An epidemiological model is described that closely mimicked results of a published serological study of natural transmission of Maedi-Visna virus in a low ground flock of sheep. We adjusted parameters in the model from this baseline to explore the possible implications for the control of Maedi-Visna virus in typical British flocks. On closed hill farms, low probability of effective contact was most critical for control. In open low ground flocks, purchasing accredited replacements eliminated disease spread, otherwise flock size was the most important factor governing flock prevalence. Results highlighted the need for more epidemiological information about Maedi-Visna, particularly whether hill farms act as a hidden reservoir of virus or reduce the impact... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Livestock Production/Industries; Maedi-Visna; Model; Markov Chain; Sheep; Control. |
| Ano: 2009 |
URL: http://purl.umn.edu/61102 |
| |
|
|
| Vosough Ahmadi, Bouda; Dwyer, Cathy M.; Erhard, H.W.; Morgan-Davies, Claire; Waterhouse, A.; Milne, Catherine E.; Kupiec-Teahan, Beata; Ringrose, Sian; Goddard, Pete; Phillips, Kate; Stott, Alistair W.. |
| This study quantified interactions between animal welfare and farm profitability in British extensive sheep farming systems. Qualitative welfare assessment methodology was used to assess welfare from the animal's perspective in 20 commercial extensive sheep farms and to estimate labour demand for welfare, based on the assessed welfare scores using data collected from farm inventories. The estimated labour demand was then used as a coefficient in a linear program based model to establish the gross margin maximising farm management strategy for given farm situations, subject to constraints that reflected current resource limitations including labour supply. Regression analysis showed a significant relationship between the qualitative welfare assessment... |
| Tipo: Conference Paper or Presentation |
Palavras-chave: Sheep; Labour; Animal Welfare; Linear Programme; Livestock Production/Industries; C6; Q10; Q19; Q57. |
| Ano: 2010 |
URL: http://purl.umn.edu/91803 |
| |
|
| |
|
|
| Stott, Alistair W.; Gunn, George J.; Varo Barbudo, Antonio. |
| A survey of the management of reproduction on 66 Scottish suckler herds calving in spring 2003 was analysed using multiple regression. The predicted mean value of suckled calves produced was £237/cow (SE 1.8). The regression coefficients of the predictors was 0.74 (0.05), 15 (3.9) and 248 (16.5) for date of first calving, average number of 21-day calving periods (calving spread) and proportion of cows barren respectively. Improving each predictor by 1 SD had the combined potential to improve predicted calf value by £64/cow, over 80% of the current typical gross margin for this type of enterprise. Bull care had a significant influence on calving spread and number of biosecurity measures taken had a positive influence on the proportion of cows barren.... |
| Tipo: Conference Paper or Presentation |
Palavras-chave: Beef cow; Fertility; Economics; Management; Livestock Production/Industries. |
| Ano: 2008 |
URL: http://purl.umn.edu/36871 |
| |
|
|
| Rat-Aspert, Olivier; Weldegebriel, Habtu T.; Stott, Alistair W.; Fourichon, C.. |
| The paper analyses the problem of information in the cattle market, particularly as it relates to the status of animal health, and discusses ways to limit it with the view to improving social surplus. Against this background, it aims to achieve three major objectives. Firstly, it describes the ways of improving the level of information through such schemes as Conventional Warranties and Third Party Certification and the different choices made by sellers and buyers in the presence of these schemes. Secondly, it studies the various ways by which these schemes make an impact on equilibria in different markets (i.e., the pooling market and the premium market), and, consequently, on the social surplus. Thirdly, it identifies the necessary conditions for a third... |
| Tipo: Conference Paper or Presentation |
Palavras-chave: Asymmetric information; Third-Party certification; Disease Externalities; Livestock Production/Industries. |
| Ano: 2008 |
URL: http://purl.umn.edu/44064 |
| |
|
|
| Stott, Alistair W.; Brulisauer, Franz; Fraser, Fiona; Gunn, George J.. |
| A methodology is described to establish the relative financial benefit of farm animal disease prevention (biosecurity). This methodology is demonstrated using the example of bovine viral diarrhoea virus (BVDV) incursion on beef suckler farms in Scotland. A random sample of 276 herds was taken and a proportion of young stock on each farm tested for previous exposure to BVDV. There was evidence that 0.4 of herds had been exposed over one year prior to sampling. All herds completed a questionnaire about their biosecurity practices. The influence of these practices on relative risk of BVDV was subjected to a Chi squared test and practices ranked accordingly. Most important risk factors were animal buying in strategy, farm size and a single farm boundary. The... |
| Tipo: Conference Paper or Presentation |
Palavras-chave: Livestock Production/Industries; Biosecurity; BVD; Economic Impact. |
| Ano: 2009 |
URL: http://purl.umn.edu/51077 |
| |
|
| |
|
|
| Stott, Alistair W.. |
| Endemic disease of animals is an economic problem as it deprives humans of scarce resources that might otherwise satisfy human wants. Optimisation methods identify the strategies that minimise this economic problem. Given the potentially vast extent of the deprivation, not only in terms of lost wealth but also in terms of animal welfare, human health and environmental damage, this subject offers great benefits to decision-makers from the individual farm to the global level. This paper uses examples to illustrate the basic economic principles concerned. It shows how these principles may be extended to deal with current limitations in theory and practice. Lack of data is a common problem that may be dealt with by using computer simulation, theoretical... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Economics; Decision analysis; Optimisation; Modelling; Endemic disease; Knowledge transfer; Health Economics and Policy. |
| Ano: 2006 |
URL: http://purl.umn.edu/46000 |
| |
|
|
| Stott, Alistair W.; Vosough Ahmadi, Bouda; Milne, Catherine E.; Morgan-Davies, Claire; Dwyer, Cathy M.; Kupiec-Teahan, Beata; Ringrose, Sian; Phillips, Kate; Waterhouse, A.. |
| A bio-economic linear program based on data from 20 commercial extensive sheep farms was used to predict the effects on aspects of farm management of response to CAP reform in Great Britain. The objective function of the LP was to maximise gross margin while meeting ewe energy requirements from farm grown or purchased feeds on a monthly basis throughout the farming year. Three farms were constrained by availability of home-grown grass and thus contracted under a subsidy free scenario. Just one farm justified expansion using extra labour purchased at £5/hour. The other farms remained at current flock sizes using existing unpaid labour. However, all farms adjusted their grazing regime according to the balance of land types available. These adjustments varied... |
| Tipo: Conference Paper or Presentation |
Palavras-chave: Productivity Analysis. |
| Ano: 2010 |
URL: http://purl.umn.edu/91826 |
| |
|
|
| Vosough Ahmadi, Bouda; Morgan, Colin A.; Stott, Alistair W.. |
| Since decoupling of the CAP, many Scottish suckler cow farms are facing financial difficulties. In response, many farmers are out-wintering extensively managed suckler cows to minimise production costs. These systems are of animal welfare concern. A range of trade-offs between animal welfare indicators and between animal welfare and farm profitability can be identified. A Dynamic Programming (DP) model was developed to study these trade-offs. Two herds were modelled assuming their feeding regimes were either low (LHERD) or high (HHERD). The objective of the DP was to maximise the expected net margin from a current cow and its successors over an infinite time horizon. Preliminary results showed that the rate of voluntary culling was higher in HHERD than in... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Livestock Production/Industries; Beef cow; Economics; Dynamic programming; Animal welfare. |
| Ano: 2009 |
URL: http://purl.umn.edu/61122 |
| |
|
|
| Vosough Ahmadi, Bouda; Morgan, Colin A.; Stott, Alistair W.. |
| Since decoupling of the CAP, many Scottish suckler cow farms are facing financial difficulties. In response, many farmers are out-wintering extensively managed suckler cows to minimise production costs. These systems are of animal welfare concern. A range of trade-offs between animal welfare indicators and between animal welfare and farm profitability can be identified. A Dynamic Programming (DP) model was developed to study these trade-offs. Two herds were modelled assuming their feeding regimes were either low (LHERD) or high (HHERD). The objective of the DP was to maximise the expected net margin from a current cow and its successors over an infinite time horizon. Preliminary results showed that the rate of voluntary culling was higher in HHERD than in... |
| Tipo: Conference Paper or Presentation |
Palavras-chave: Beef cow; Economics; Dynamic programming; Animal welfare; Livestock Production/Industries. |
| Ano: 2009 |
URL: http://purl.umn.edu/51078 |
| |
|
|
| Weldegebriel, Habtu T.; Gunn, George J.; Stott, Alistair W.. |
| In this paper, we evaluated the welfare effects of a hypothetical programme of Johne's disease eradication from the Scottish dairy herd on different stakeholders in the domestic milk market. We undertook the evaluation using a Markov-Chain simulation and applying an economic welfare analysis which takes into consideration the effects of an eradication programme on product price, on output quantity, on cost and on milk yield for given levels of supply and demand elasticities. We found that, following the eradication of the disease, milk yield per cow increased for all herd sizes in Scotland whereas price and unit cost of milk production fell. Consequently, milk consumers gained around £14.3 million in discounted economic surplus and producers with infected... |
| Tipo: Conference Paper or Presentation |
Palavras-chave: Johne's; Eradication programme; Economic welfare effects; Economic surplus; I180. |
| Ano: 2008 |
URL: http://purl.umn.edu/36872 |
| |
| Registros recuperados: 16 | |
|
|
|
