Organic dairy cows: milk yield and lactation characteristics in thirteen established herds and development of a herd simulation model for organic milk production

As a consequence of organic standards and principles, organic dairy producers are frequently faced with a different set of management considerations than those found in conventional dairy systems. The broad objective of this study was to examine in detail the production characteristics of 13 well-established organic dairy herds, and to relate these to the specific conditions that exist within organic dairy farming. Monthly milk records for 13 organic herds for three years were collected and converted into a Microsoft Access database, using InterHerd™ (Agrisoft Plc., UK) herd management software. The data were sorted and analysed using the InterHerd-herd management, Excel for Windows™ and Statistix for Windows software programmes. Estimated parameters were used to examine the importance of two important indicators: lifetime yield/lactation length and economic efficiency. To assess the first, a spreadsheet model based on the Wood's lactation curve was developed. With regard to the latter, a model calculator was used. Five herds were chosen for case studies, that examined the farm performance by using InterHerd™-generated data and by interviewing the producer retrospectively and asking him to comment on the data. Results Milk yield and lactation characteristics The 13 established, organic herds were characterised with relatively low yields, but herd variation was great: from a total lactation yield of 5,100 kg to 7,000 kg. Milk fat and protein content, lactation length and individual cow SCC means were similar to those reported in conventional, milk recorded herds. Lactation yields increased up to the third lactation, whereas persistency of lactations decreased up to the third lactation. This pattern followed similar patterns reported in conventionally managed herds. Similarly, somatic cell counts increased with parity, mimicking similar phenomenon reported in conventionally managed dairy cows. Length of lactation and lactation persistency were associated with month of calving, with autumn calving cows tending to have shorter lactations with better persistency. This phenomenon was, however, confounded with parity. Fertility It is concluded that fertility performance in terms of culling for fertility and mean calving intervals were better in the organic survey herds when compared with existing data from conventionally managed UK dairy herds. Good fertility performance even in the highest yielding organically managed cows suggests that early lactation energy deficit may not be a major problem in these herds. It is also suggested that financial impact of high number of services per conception, as observed in majority of the survey herds, may be insignificant as the main losses caused by poor fertility are attributable to culling and prolonged calving intervals. Herd models Herd productivity indices were generated, using an existing model based on a measure of feed conversion efficiency at the herd level. The advantage of using this approach in the estimation of productivity is that it takes full account of the entire feed input to the system, including forage. The production index was closely and independently associated with yield and calving rate. Culling was not independently associated with the production index but once calving rate and lactation yield are taken into account, culling rate also becomes a significant factor. Case studies Case studies demonstrated the usefulness of recorded data analysis, using herd management software and observation of seasonally adjusted lactation curves to examine feeding management. In all five herds, apparent and reoccurring seasonal feeding and grazing management shortcomings were detected. Recommendations Further research would need to be carried out to establish financial consequences of poor fertility in organic systems with different milk pricing and cow values. Similarly, further research is needed to establish causes for high numbers of services per conception in these herds and to establish whether this phenomenon exists in other organically managed herds. The herd productivity calculator model (LPEC) showed to be a good and robust measure of productivity. Next logical step in this analysis would be to gain data on purchased feeds, so that the productivity index can be expressed in terms of a gross margin per unit of forage input. This would allow the full importance of forage to organic dairy systems to be expressed, and would also allow productivity to be evaluated in terms economic margin per unit of input produced on-farm. The LPEC generated indices could also be utilised to examine the potential impact of changes to systems before an intervention is implemented, by including costs of intervention and assumed values of production post-intervention. Sensitivity analyses may be conducted to identify the relative importance of individual production parameters to overall herd productivity. Careful assessment of lactation characteristics in a herd is needed to predict the overall impact of extended calving intervals. It is likely that in most organic herds feeding management would need to be adjusted in order to produce lactations with low late lactation decline to avoid financial losses caused by longer calving intervals. Analysis of seasonally adjusted lactation curves as a monitoring and decision support system for feeding management is likely to be a useful for organic herds, particularly during conversion period when new feeding systems need to be introduced in a herd

Animal Health Plans for Organic Livestock Farms

The new UKROFS Standards require organic farmers to prepare an animal or livestock health plan. This should aim to be prevent disease by means of suitable breeds, good husbandry, quality feed, regular exercise and access to pasture and appropriate stocking densities. This article gives an introduction to the process and explains the help that is available

Vaccine use in organic cattle and sheep systems: Development of a decision support tool based on risk assessment

This project’s aim was to support a consistent approach to decision making on vaccine use among organic dairy, beef and sheep farmers and their advisers, including their veterinarians, by developing a decision support tool on vaccine use in order: a) to help organic livestock producers and their veterinarians to assess an individual farm situation in relation to a specific disease risk, to implement specific risk management measures and to communicate the decision with adequate precision to the certification bodies; and b) to provide certification bodies with baseline information on risk factors and risk management measures and their significance, so that the could judge veterinary/farmer decisions on vaccine use adequately. The project focused on 10 cattle and 14 sheep diseases that are routinely vaccinated against in the UK. A web-based, interactive decision support tool (DestVAC, www.destvac.reading.ac.uk) was created using ASP.NET and SQL Server Database. The tool allows farm specific exploration of risk factors and risk management measures, access to additional information on vaccines, exposure and financial impact of disease at farm level. The tool also allows the user to produce reports on individual farm assessments or exploratory scenario building for submission to certification bodies as part of a health plan

Organic Livestock: Animal Health, Welfare and Husbandry Assessment of existing knowledge and production of an advisory resource compendium(OF0162)

1. A compendium of animal health and welfare information relevant to organic livestock production has been produced by the Organic Livestock Research Group (OLRG), Veterinary Epidemiology and Economics Research Unit (VEERU), Department of Agriculture, the University of Reading. The compendium is supported by full scientific abstracts taken from the CAB International information database. 2. The objective of the project was to: - Create a database and archive of information on animal health, welfare and husbandry relevant to livestock production under organic standards; - Assess the database and its relevance to organic livestock production; - Develop a series of compendia of advisory resource materials on CD-ROM and in printed format, in consultation with relevant sector bodies, the veterinary profession and organic livestock producers. 3. The compendium has been produced in a CD ROM format and is internet accessible (http://www.organic-vet.reading.ac.uk/). The compendium has been reviewed by specialist veterinarians, advisors and farmers. For copyright purposes, the internet accessible version has been produced without scientific abstracts 4. The aim of the compendia is to serve as a resource material for advisors, inspectors and veterinarians who work with organic or converting farmers in the UK. It is also envisaged that the compendia could be used as a training tool for advisors and veterinarians learning about the issues related to general and specific animal health and welfare aspects of organic livestock production. In addition, the material will provide a useful resource material for the sector bodies and policymakers in the development of organic livestock production standards and regulations. 5. Each compendium is divided into four sub-compendia: Cattle, Sheep, Pigs and Poultry. Each is further divided into two sections. An introductory section, Health and Welfare, outlines general health and welfare issues related to the specific organic production system. Emphasis is placed on the requirements of organic standards in the approach to health and welfare problems. A second section, accessible via the Disease Index, deals in detail with the specific conditions affecting the species in question. Each disease is indexed alphabetically, and by the veterinary and common terms normally applied. 6. The Disease Section describes a range of specific condition is divided further into sub-sections on causes, symptoms, treatment, control, prevention, welfare implications, good practice based on current knowledge and guidelines for the conversion period. The poultry compendium does not contain a sub-section on the conversion period as there is little technical information available to support this. 7. In total, the compendium covers 45 cattle, 44 sheep, 32 poultry and 27 pig diseases and conditions. 8. Each section is supported throughout by references to scientific literature and other publications. These references can be accessed directly from the text by using text links to scientific abstracts, scanned-in advisory materials and reference or reading lists. 9. The compendium has Help and Search facilities. 10. At the time of publication. the compendium contains over 1700 scientific references and more than 50 full advisory documents. It is intended that this particular feature of the compendia will prove useful when in-depth information is sought, or the compendia are used as a training tool. 11. It should be emphasised that the compendium is not intended as a diagnostic or self-help tool for animal health management on the farm. For this reason, diagnostics are not covered in any depth, and the treatment sections usually only suggest potential treatment categories and discuss the urgency and need for treatment from an animal welfare perspective. The authors wish it to be known that diagnosis should always be carried out by a veterinary surgeon, in response to problems seen on a farm. 12. The compendium have been reviewed by members of the advisory team at the Organic Advisory Service on Elm Farm Research Centre in Berkshire, by specialist veterinarians and by organic farmers. 13. In light of the rapid developments within organic farming and research, it is proposed that the information contained within the compendium will require frequent updating, probably on an annual basis. A proposal for the maintenance and expansion of the compendium has been included within the final proposal. The main component of this proposal is the development of a “stakeholder club” of interested parties, whose function would be to raise financial support, to supply technical information and to provide a practical link to the organic farming, advisory and administrative sectors

Feeding for health and welfare

Content: Feeding of livestock in organic production systems was discussed in four different groups: beef production, dairy production, pig production and poultry production. A. Beef production The general consensus was that most of these problems require solutions on management and systems level, rather than further nutritional research. Research and development needs are described. B. Dairy production The discussion on health and welfare related problems in dairy feeding focused on many issues. Some management solutions are given. Research and development needs are demonstrated. C. Pig production Research and development needs are demonstrated. D. Poultry production Potential solutions to these problems were suggested. Research and development needs are displayed

Comparative study of spanning cluster distributions in different dimensions

The probability distributions of the masses of the clusters spanning from top to bottom of a percolating lattice at the percolation threshold are obtained in all dimensions from two to five. The first two cumulants and the exponents for the universal scaling functions are shown to have simple power law variations with the dimensionality. The cases where multiple spanning clusters occur are discussed separately and compared.Comment: 8 pages, latex, 4 eps figures included, to appear in Int. Journal of Modern Physics

Animal health and welfare in organic livestock production in Europe– current state and future challenges

Existing data on animal health and welfare in organic livestock production systems in the European Community countries are reviewed in the light of the demands and challenges of the recently implemented EU regulation on organic livestock production. The main conclusions and recommendations of a three-year networking project on organic livestock production are summarised and the future challenges to organic livestock production in terms of welfare and health management are discussed. The authors conclude that, whilst the available data are limited and the implementation of the EC regulation is relatively recent, there is little evidence to suggest that organic livestock management causes major threats to animal health and welfare in comparison with conventional systems. There are, however, some well-identified areas, like parasite control and balanced ration formulation, where efforts are needed to find solutions that meet with organic standard requirements and guarantee high levels of health and welfare. It is suggested that, whilst organic standards offer an implicit framework for animal health and welfare management, there is a need to solve apparent conflicts between the organic farming objectives in regard to environment, public health, farmer income and animal health and welfare. The key challenges for the future of organic livestock production in Europe are related to the feasibility of implementing improved husbandry inputs and the development of evidence-based decision support systems for health and feeding management. (HOVI, M., A. SUNDRUM and S. M. THAMSBORG (2003): Animal health and welfare in organic livestock production in Europe – current state and future challenges. Livestock production science 80, 41-53.

Renegotiation Proofness and Climate Agreements: Some Experimental Evidence

The notion of renegotiation-proof equilibrium has become a cornerstone in non-cooperative models of international environmental agreements. Applying this solution concept to the infinitely repeated N-person Prisoners' Dilemma generates predictions that contradict intuition as well as conventional wisdom about public goods provision. This paper reports the results of an experiment designed to test two such predictions. The first is that the higher the cost of making a contribution, the more cooperation will materialize. The second is that the number of cooperators is independent of group size. Although the experiment was designed to replicate the assumptions of the model closely, our results lend very little support to the two predictions.

The productivity of organic dairy herds

This report was presented at the UK Organic Research 2002 Conference. Organically managed ruminant systems place particular emphasis on maximising production from forage. Therefore, it is important that efficiency measures take full account of forage inputs. The Livestock Production Efficiency Calculator (LPEC) calculates the total metabolisable energy (ME) required by livestock and estimates forage inputs as the difference between total requirement and that supplied by other measured feeds. Productivity is expressed in terms of output (£) minus other valued inputs (£) per unit of forage ME. Estimates of production parameters were used to produce productivity indices for thirteen organic dairy herds. The productivity of herds was compared, and sensitivity analyses were conducted to examine the potential impact of a number of economic and production scenario. The relationships between yield, fertility, culling and herd productivity were examined. The advantages of this productivity analysis of organic production systems is that full account is taken of the most important input i.e. grazed and conserved forage and that all of the determinants of productivity and their interactions are considered

Fertility and fertility management in thirteen well-established organic dairy herds in the UK

This report was presented at the UK Organic Research 2002 Conference of the Colloquium of Organic Researchers (COR). Milk production and breeding records from thirteen organic dairy herds were collected between January 1997 and December 1999. Mean lactation yields in the herds ranged from 5127 kg to 7031 kg. Whilst seasonality of calving varied widely between herds, a majority of them (6/13) were autumn calving. Mean calving to first service interval was 80 days (range 68 to 97), and mean calving interval was 385 days (range 370 to 413). The mean number of services per conception was 2.3 (range 1.6 to 3.1). Overall culling rates and culling rates for fertility related problems were at 15.8% and 5.4%, respectively. A preliminary study of selected breeding periods of cows that had a subsequent calving revealed no significant differences in calving interval between high or low yielding cows or between cows with different calving month or parit