The quality assurance of proficiency testing programs for animal disease diagnostic laboratories.

Laboratory data credibility has 3 major components: 1) valid methods, 2) proficiency testing (PT) to verify that the analyst can conduct the method and to compare results of other laboratories using the same method, and 3) third-party accreditation to verify that the laboratory is competent to conduct testing and that the method validation has been done within the environment and requirements of an effective quality-management system. Participation in external PT programs by a laboratory is strongly recommended in International Organization for Standardization/International Electrotechnical Commission International Standard 17025. Most laboratory accreditation bodies using this standard require that laboratories participate in such programs to be accredited. Internal PT is also recommended for each analyst. Benchmarking, or comparison between laboratories using PT or reference materials, is also recommended as part of the validation and evaluation of test methods. These requirements emphasize the need for proficiency test providers to demonstrate their competence. Requirements for competence are documented in national and international standards and guidelines, and accreditation is available for providers. This article discusses the activities and the components that are necessary and recommended for PT projects and programs for animal disease diagnostic testing. These are based on the requirements of the national and international standards, which address this subject, and on the experience of the author. The accreditation of external PT programs is also discussed. Organizations that accredit PT providers or that provide PT programs are listed. Existing references, guidelines, and standards that are relevant to PT in veterinary diagnostic laboratories are discussed.     

Internal restriction sites: quality assurance aids in genotyping.

Improvements to restriction fragment length polymorphism (RFLP)-based genotyping assays currently used for detection of mutations responsible for bovine ferrochelatase and myophosphorylase deficiencies, and equine hyperkalemic periodic paralysis (HYPP) are described. Reports of sporadic inhibition of restriction enzyme activity suggest a critical factor in RFLP-based genotyping assays should be assurance that restriction enzymes perform to specification with every sample. The RFLP genotyping assays that use either a mismatched recognition sequence in one or both of the oligonucleotides, or incorporate a second native site within the PCR amplicon, provide the mechanism by which efficiency of restriction enzymes can be assessed with every sample. The outcome is confirmation of the activity of the discriminating enzyme regardless of genotype.     

饲料企业中QA的作用与职责

<正>饲料企业是原料依赖型企业。作为饲料企业,饲料原料占生产成本的70%￣90%,饲料原料的质量变异占产品质量变异的40%￣70%,饲料原料质量是保证产品质量的关键因素和重要前提,营养品质和安全指标中,过去被忽视的影响因素或质量"细节",可能     

全价饲料品质保证技术

1饲料产品安全性保证技术饲料产品的安全性是评判饲料产品质量的一个重要指标。要保证饲料安全,就是要保证饲料产品(包括饲料和饲料添加剂)一般的卫生指标(铅、砷、氟、黄曲霉素B1等)在国标范围内,不含有对饲养动物健康造成实际危害,在动物体内的残留造成整个食物链的安全隐患,     

Epidemiology and quality assurance application to food safety

The conditions for the food industry, in general, are changing. Especially in industrialized countries, the safety and quality of food is increasingly becoming an issue of concern to the consumer. This paper describes the impact of the farm-to-table concept and the implementation of HACCP plans throughout the food production chain on animal production and veterinary profession, using the example of the pork production chain.     

Progress in national control and assurance programs for ovine Johne's disease in Australia

Since the detection of ovine Johne's disease in Australia in 1980, 578 flocks have been diagnosed as infected, with 442 of these still infected. The disease was initially believed to be confined to the central tablelands area of NSW, but has subsequently been shown to be more widely distributed. Sheep strains of M. paratuberculosis are known to infect sheep and goats in south-eastern Australia. Although sheep strains have recently been identified in some cattle in Australia, epidemiological evidence to date supports the distinction between ovine Johne's disease, caused by sheep strains in sheep and goats, and bovine Johne's disease, caused by cattle strains in cattle, goats and alpaca, as a basis for control and eradication strategies. Four national initiatives to control and better understand OJD are outlined. The Australian Johne's Disease Market Assurance Program for sheep was launched in May 1997. By December 1998, 548 flocks had achieved an assessed negative status. Three flocks assigned a flock status have subsequently been found to be infected. National standards for State control of Johne's disease through zoning, movement controls and procedures in infected and suspect flocks have also been developed. In addition, a $40.1 m National Ovine Johne's Disease Control and Evaluation Program was agreed to in August 1998, and is currently being implemented. It is jointly funded by National and State industries, and Commonwealth and State governments. Its objectives are to deliver, through research and surveillance, a solid basis for a future decision on the most appropriate course for dealing with OJD and to maintain control of OJD nationally.     

Progress in national control and assurance programs for bovine Johne's disease in Australia

Cattle strains of Mycobacterium paratuberculosis are known to infect cattle, goats and alpaca in southeastern Australia, where there are also significant numbers of farmed deer. Although sheep strains have recently been identified in some cattle in Australia, epidemiological evidence to date supports the distinction (between bovine Johne's disease (JD), caused by cattle strains in cattle, goats and alpaca, and ovine JD, caused by sheep strains in sheep and goats) for the purposes of control and assurance programs. The National Johne's Disease Control Program is coordinated by the Australian Animal Health Council, working with the livestock industries and with the Commonwealth, state and territory governments. The council also brokers industry and government funding for the program. The National Johne's Disease Market Assurance Program for Cattle was launched in 1996 as the first of a suite of voluntary national market assurance programs (MAPs) to assess and certify herds as negative for JD. By December 1998, over 550 herds had achieved an assessed negative status. A MAP was also launched for alpaca in 1998 and a program for goats should be finalized in early 1999. National standards for state control of JD through zoning, movement controls and procedures in infected and suspect herds have also been developed. The paper covers factors affecting development and implementation, uptake of and improvements to national control and assurance programs for bovine JD in Australia.     

Epidemiology and quality assurance: applications at farm level

Animal production is relevant with respect to farm income and the position of the sector in the market, but also with respect to the quality and safety of products of animal origin, related to public health. Animal production is part of a chain of food production. Therefore, producers have to take consumer expectations and demands in the domains of animal health, welfare and environment into account. A different attitude for production has to be adopted; this attitude can be visualized in good farming practice, GFP, codes. Farmers who focused on quality in its broadest sense need a system supporting them in their management and control of quality risks. Generally speaking, there are three systems for that purpose: GFP, ISO and HACCP. When the hypothesis followed relates to animal health being a feature of quality, or else welfare and environmental issues, then animal health care can be executed following quality control principles. The HACCP concept is well suited for quality control at farm level, involving risk identification and risk management. The on-farm monitoring and surveillance system of critical control points in the animal production process is the most important tool in this procedure. Principles for HACCP application as well as certification fitness of HACCP are elaborated upon. They are illustrated by using salmonellosis in meat-pig farms as objective for an HACCP approach. It is further discussed that, in addition to animal health and quality, animal welfare and environmental issues could also be covered by an HACCP-like system in an integrated manner. Ultimately, the HACCP modules could end up in an overall ISO certification.     

Methodologic aspects of quality assurance in veterinary epidemiological studies]

In planning and conducting epidemiological studies the quality of the investigation should be sufficient to take care that all possible conclusions are correct. In this paper we deal with these parts of epidemiological studies which are related to quality and therefore have to be under control. This is done in the view of veterinary medicine.     

The need for implementation of International Commission on Trichinellosis recommendations, quality assurance standards, and proficiency sample programs in meat inspection for trichinellosis in Serbia

Implementation of methods to control inspection for Trichinella in meat recommended by International Commission on Trichinellosis (ICT), particularly the introduction of the quality assurance standards and proficiency panels for certified analysts is extremely important in Serbia and other countries where Trichinellosis is endemic. In spite of existing regulations, including the inspection of 0.5 g samples of diaphragm by the compression method or by artificial digestion of 1g samples, in Serbia 280 people were diagnosed with clinical trichinellosis after consumption of inspected meat during the period 2001--2002. These outbreaks, which occurred in the municipalities of Kumane, Surcin and Bogatic, were a consequence of inadequate application of inspection methods and insufficient education of some veterinary inspectors. The problem of inadequate veterinary inspection in Serbia can be overcome by strict application of the ICT recommendations for the control of Trichinella with specific emphasis on implementing the quality assurance system (QAS) and proficiency sampling (PS/--PP/panel).     

Vaccines against hemoparasitic diseases in Israel with special reference to quality assurance

Tropical Animal Health and Production - Four vaccines against hemoparasitic diseases (anaplasmosis, babesiosis and theileriosis) and a vaccine against besnoitiosis are currently used in Israel....     

Milk quality assurance for paratuberculosis: simulation of within-herd infection dynamics and economics

A bulk milk quality assurance programme for Mycobacterium avium subsp. paratuberculosis (Map) in dairy herds was simulated with a stochastic simulation model (JohneSSim). The aim of this study was to evaluate the epidemiological and economic effects of preventive management measures and various test schemes in a simulated population of closed Dutch dairy herds over a 20-year period. Herds were certified as ;low-Map bulk milk' if, with a certain probability, the concentration of Map in bulk milk did not exceed a maximum acceptable concentration of 10(3) Map organisms per litre (based on pasteurisation studies). The programme started with an initial assessment; test-negative herds entered a surveillance procedure and test-positive herds a control procedure. The simulations showed that herd examinations by ELISA for the initial assessment, surveillance and control procedures effectively ensure the quality of ;low-Map bulk milk': > 75% of simulated herds were certified and > 96% of certified herds produced bulk milk with < 10(3) Map/L if the initial herd-level prevalence was 30%. Preventive management measures only had a minor effect on bulk milk quality of certified herds. Culling based on biennial faecal culture was more effective than culling based on annual ELISA. Average total discounted costs for 20-year participation in a programme consisting of initial assessment by ELISA, surveillance by biennial ELISA and control by biennial faecal culture were 16 Euro x 10(3) per herd. In conclusion, this study shows that a bulk milk quality assurance programme for closed Dutch dairy herds is feasible and provides information on the cost-effectiveness of different programmes. The concepts of this study equally apply to other countries because mechanisms of paratuberculosis infection, disease, and testing are comparable in other dairy cattle populations.