Availability of online educational content concerning topics of animal welfare.

Animal welfare is an important area of study for professionals in fields of animal care and use, and many turn to self-learning resources to gain a better understanding of topics in this area. We assessed the state of these self-learning resources by evaluating open access, freely available resources on the internet with respect to their content and the reliability of their information. We categorized content using a modified list of the topics described in the American College of Animal Welfare's Role Delineation Document, and we identified subject areas that are underrepresented among freely available resources. We identified that the field needs more content describing practical information on subtopics of animal transportation, humane education and economic issues in animal welfare. We also suggest a targeted approach to improve and increase particular aspects of content that concerns the impacts of human, animal and environment interactions on animal welfare. We recommend that veterinary societies place more emphasis on welfare policies in their websites. Additionally, the field of animal welfare would benefit from more available and authoritative information on certain species and uses of animals that are presently underrepresented.

A global initiative to refine acute inhalation studies through the use of 'evident toxicity' as an endpoint: Towards adoption of the fixed concentration procedure.

Acute inhalation studies are conducted in animals as part of chemical hazard identification and characterisation, including for classification and labelling purposes. Current accepted methods use death as an endpoint (OECD TG403 and TG436), whereas the fixed concentration procedure (FCP) (draft OECD TG433) uses fewer animals and replaces lethality as an endpoint with 'evident toxicity.' Evident toxicity is defined as clear signs of toxicity that predict exposure to the next highest concentration will cause severe toxicity or death in most animals. A global initiative including 20 organisations, led by the National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) has shared data on the clinical signs recorded during acute inhalation studies for 172 substances (primarily dusts or mists) with the aim of making evident toxicity more objective and transferable between laboratories. Pairs of studies (5 male or 5 female rats) with at least a two-fold change in concentration were analysed to determine if there are any signs at the lower dose that could have predicted severe toxicity or death at the higher concentration. The results show that signs such as body weight loss (>10% pre-dosing weight), irregular respiration, tremors and hypoactivity, seen at least once in at least one animal after the day of dosing are highly predictive (positive predictive value > 90%) of severe toxicity or death at the next highest concentration. The working group has used these data to propose changes to TG433 that incorporate a clear indication of the clinical signs that define evident toxicity.

Performance standards and alternative assays: practical insights from skin sensitization.

To encourage the development and validation of alternative toxicity test methods, the effort required for validation of test methods proposed for regulatory purposes should be minimized. Performance standards (PS) facilitate efficient validation by requiring limited testing. Based on the validated method, PS define accuracy and reliability values that must be met by the new similar test method. The OECD adopted internationally harmonized PS for evaluating new endpoint versions of the local lymph node assay (LLNA). However, in the process of evaluating a lymph node cell count alternative (LNCC), simultaneous conduct of the regulatory LLNA showed that this standard test may not always perform in perfect accord with its own PS. The LNCC results were similar to the concurrent LLNA. Discrepancies between PS, LLNA and LNCC were largely associated with "borderline" substances and the variability of both endpoints. Two key lessons were learned: firstly, the understandable focus on substances close to the hazard classification borderline are more likely to emphasise issues of biological variability, which should be taken into account during the evaluation of results; secondly, variability in the results for the standard assay should be considered when selecting reference chemicals for PS.

Using fewer animals to identify chemical eye hazards: revised criteria necessary to maintain equivalent hazard classification.

U.S. Federal Hazardous Substances Act (FHSA) regulations specify eye safety testing procedures and hazard classification criteria for substances regulated by the U.S. Consumer Product Safety Commission (CPSC). Current regulations require up to three sequential 6-animal tests. Testing consistent with the Organisation for Economic Co-operation and Development (OECD) test guideline for eye irritation/corrosion, which specifies 3 animals, can also be submitted to US agencies. However, current FHSA regulations do not provide criteria to classify results from 3-animal tests. An analysis was conducted to determine criteria using results from 3-animal tests that would provide equivalent labeling to FHSA regulations. The frequency that FHSA requirements identify substances as ocular irritants was compared with the frequency that a criterion of either ≥ 1/3 or ≥ 2/3 positive animals would identify these substances. A database of rabbit eye tests was also used to estimate over- and underprediction rates for each criterion. In each instance, a criterion of ≥ 1/3 positive animals more closely matched the expected outcome based on FHSA requirements, while a criterion of ≥ 2/3 positive animals identified far fewer irritants. Using a classification criterion of ≥ 1/3 positive animals provided equivalent or greater eye hazard labeling as current FHSA requirements, while using 50-83% fewer animals.

Safety assessment of allergic contact dermatitis hazards: an analysis supporting reduced animal use for the murine local lymph node assay.

The original Organisation for Economic Co-operation and Development Test Guideline 429 (OECD TG 429) for the murine local lymph node assay (LLNA) required five mice/group if mice were processed individually. We used data from 83 LLNA tests (275 treated groups) to determine the impact on the LLNA outcome of reducing the group size from five to four. From DPM measurements, we formed all possible four- and five-mice combinations for the treated and control groups. Stimulation index (SI) values from each four-mice combination were compared with those from five-mice combinations, and agreement (both SI<3 or both SI ≥ 3) determined. Average agreement between group sizes was 97.5% for the 275 treated groups. Compared test-by-test, 90% (75/83) of the tests had 100% agreement; agreement was 83% for the remaining eight tests. Disagreement was due primarily to variability in animal responses and closeness of the SI to three (positive response threshold) rather than to group size reduction. We conclude that using four rather than five mice per group would reduce animal use by 20% without adversely impacting LLNA performance. This analysis supported the recent update to OECD TG 429 allowing a minimum of four mice/group when each mouse is processed individually.

Non-animal replacement methods for veterinary vaccine potency testing: state of the science and future directions.

NICEATM and ICCVAM convened an international workshop to review the state of the science of human and veterinary vaccine potency and safety testing methods and to identify opportunities to advance new and improved methods that can further reduce, refine, and replace animal use. Six topics were addressed in detail by speakers and workshop participants and are reported in a series of six reports. This workshop report, the second in the series, provides recommendations for current and future use of non-animal methods and strategies for veterinary vaccine potency testing. Workshop participants recommended that future efforts to replace animal use give priority to vaccines (1) that use large numbers of animals per test and for which many serials are produced annually, (2) that involve significant animal pain and distress during procedures, (3) for which the functional protective antigen has been identified, (4) that involve foreign animal/zoonotic organisms that are dangerous to humans, and (5) that involve pathogens that can be easily spread to wildlife populations. Vaccines identified as the highest priorities were those for rabies, Leptospira spp., Clostridium spp., Erysipelas, foreign animal diseases (FAD), poultry diseases, and fish diseases. Further research on the identification, purification, and characterization of vaccine protective antigens in veterinary vaccines was also identified as a priority. Workshop participants recommended priority research, development, and validation activities to address critical knowledge and data gaps, including opportunities to apply new science and technology. Recommendations included (1) investigations into the relative impact of various adjuvants on antigen quantification assays, (2) investigations into extraction methods that could be used for vaccines containing adjuvants that can interfere with antigen assays, and (3) review of the current status of rabies and tetanus human vaccine in vitro potency methods for their potential application to the corresponding veterinary vaccines. Workshop participants recommended enhanced international harmonization and cooperation and closer collaborations between human and veterinary researchers to expedite progress. Implementation of the workshop recommendations is expected to advance alternative in vitro methods for veterinary vaccine potency testing that will benefit animal welfare and replace animal use while ensuring continued protection of human and animal health.

Best practices for the use of animals in toxicological research and testing.

Animal models serve an important role in assessing preclinical safety and efficacy of new medicines and vaccines; however, such assessments can involve significant pain and distress and large numbers of animals. Best practice approaches seek to enhance animal well-being, minimize or avoid pain and distress, and use fewer animals. Advances in science and technology are providing opportunities for improved mechanism-based models and integrated safety assessments that will support improved animal welfare and reduce animal use.

Validation of innovative technologies and strategies for regulatory safety assessment methods: challenges and opportunities.

Advances in science and innovative technologies are providing new opportunities to develop test methods and strategies that may improve safety assessments and reduce animal use for safety testing. These include high throughput screening and other approaches that can rapidly measure or predict various molecular, genetic, and cellular perturbations caused by test substances. Integrated testing and decision strategies that consider multiple types of information and data are also being developed. Prior to their use for regulatory decision-making, new methods and strategies must undergo appropriate validation studies to determine the extent that their use can provide equivalent or improved protection compared to existing methods and to determine the extent that reproducible results can be obtained in different laboratories. Comprehensive and optimal validation study designs are expected to expedite the validation and regulatory acceptance of new test methods and strategies that will support improved safety assessments and reduced animal use for regulatory testing.

Neutral red uptake cytotoxicity tests for estimating starting doses for acute oral toxicity tests.

In vitro cytotoxicity assays can be used as alternative toxicity tests to reduce the total number of animals needed for acute oral toxicity tests. This unit describes two methods for determining the in vitro cytotoxicity of test substances using neutral red uptake (NRU) and using the in vitro data to determine starting doses for in vivo acute oral systemic toxicity tests, e.g., the up-and-down procedure or the acute toxic class method. The use of the NRU methods to determine starting doses for acute oral toxicity tests may reduce the number of animals required, and for relatively toxic substances, this approach may also reduce the number of animals that die or require humane euthanasia due to severe toxicity. An interlaboratory validation study has demonstrated that the methods are useful and reproducible for these purposes. Two standardized protocols provide details for performing NRU tests with rodent and human cells.

Mobilizing mobile medical units for hurricane relief: the United States Public Health Service and Broward County Health Department response to hurricane Wilma, Broward County, Florida.

OBJECTIVES: To describe the outcomes of a collaborative response of federal, state, county, and local agencies in conducting syndromic surveillance and delivering medical care to persons affected by the storm through the use of mobile medical units. METHODS: Nine mobile medical vans were staffed with medical personnel to deliver care in communities affected by the storm. Individual patient encounter information was collected. RESULTS: A total of 14,033 housing units were approached and checked for occupants. Of residents with whom contact was made, approximately 10 percent required medical assessment in their homes; 3,218 clients were medically evaluated on the mobile medical vans. Sixty-two percent of clients were female. The most common presenting complaints included normal health maintenance (59%), upper respiratory tract illness (10%), and other illness (10%). Injuries occurred in 9 percent. A total of 1,531 doses of medications were dispensed from the mobile medical units during the response. CONCLUSION: Mobile medical units provided an efficient means to conduct syndromic surveillance and to reach populations in need of medical care who were unable to access fixed local medical facilities.

Selecting appropriate animal models and experimental designs for endocrine disruptor research and testing studies.

Evidence that chemicals in the environment may cause developmental and reproductive abnormalities in fish and wildlife by disrupting normal endocrine functions has increased concern about potential adverse human health effects from such chemicals. US laws have now been enacted that require the US Environmental Protection Agency (EPA) to develop and validate a screening program to identify chemicals in food and water with potential endocrine-disrupting activity. EPA subsequently proposed an Endocrine Disruptor Screening Program that uses in vitro and in vivo test systems to identify chemicals that may adversely affect humans and ecologically important animal species. However, the endocrine system can be readily modulated by many experimental factors, including diet and the genetic background of the selected animal strain or stock. It is therefore desirable to minimize or avoid factors that cause or contribute to experimental variation in endocrine disruptor research and testing studies. Standard laboratory animal diets contain high and variable levels of phytoestrogens, which can modulate physiologic and behavioral responses similar to both endogenous estrogen as well as exogenous estrogenic chemicals. Other studies have determined that some commonly used outbred mice and rats are less responsive to estrogenic substances than certain inbred mouse and rat strains for various estrogen-sensitive endpoints. It is therefore critical to select appropriate biological models and diets for endocrine disruptor studies that provide optimal sensitivity and specificity to accomplish the research or testing objectives. An introduction is provided to 11 other papers in this issue that review these and other important laboratory animal experimental design considerations in greater detail, and that review laboratory animal and in vitro models currently being used or evaluated for endocrine disruptor research and testing. Selection of appropriate animal models and experimental design parameters for endocrine disruptor research and testing will minimize confounding experimental variables, increase the likelihood of replicable experimental results, and contribute to more reliable and relevant test systems.

The FDA's regulatory role in the ICCVAM process.

The Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM), a permanent body set forth in the ICCVAM Authorization Act of 2000 (Public Law 106-545), is charged with establishing criteria and processes for the validation and regulatory acceptance of toxicological test methods of interest to Federal agencies, including alternative methods that reduce, refine, or replace the use of animals for research and testing purposes. In response to that mandate, 15 Federal regulatory and research agencies and programmes that would consider utilising such methods or the results derived from them, now participate in cross-agency efforts directed toward the identification, standardisation, validation, acceptance, regulatory implementation and international harmonisation and adoption of such test methods. As an integral member of ICCVAM since its inception, the US Food and Drug Administration (FDA) has established processes for responding to ICCVAM issues and recommendations. The participating FDA units include all FDA research and product-based centres and oversight offices. FDA product centres respond to distinct regulatory mandates and regulate different products. Upon completion of a validation effort, ICCVAM forwards its recommendations to member Government agencies regarding the validity and technical acceptability of a method. The FDA's response consists of the conclusions reached by each of its regulatory components and addresses such factors as their concurrence with ICCVAM's conclusions, the practical applicability of the method to the products they regulate and the feasibility of implementation of an accepted method to supplement or supplant those currently used. Each centre/office independently determines which of the ICCVAM-recommended tests are appropriate for implementation to satisfy its regulatory obligations to ensure product safety and to protect human health. The adoption of a method triggers a notification process to announce the availability and utility of a method, encourage its use, and inform, educate and train end-users and regulatory review staff.

The ICLAS/CCAC International Symposium on Regulatory Testing and Animal Welfare.

The first International Symposium on Regulatory Testing and Animal Welfare (ISRTAW), held 21-23 June 2001, in Quebec City, Canada, brought together 160 experts from 22 countries from North and South America, Europe and Asia. The experts included representatives from national research and regulatory agencies, universities, and industry involved in chemicals, pesticides and drug safety testing. Representatives from European, Canadian and US animal welfare groups also participated in the discussions. The Symposium was organised by the International Council for Laboratory Animal Science (ICLAS) and the Canadian Council on Animal Care (CCAC), with the support and assistance of many sponsors and advisors. ICLAS is a worldwide organisation whose purpose is to foster the international harmonisation of animal care and use practices. CCAC is the national agency responsible for overseeing the ethical use of animals in Canadian science. Both organisations are committed to fostering an environment in which global efforts to harmonise testing procedures using animals in a more-humane manner can be realised.

Humane endpoints for laboratory animals used in regulatory testing.

Laboratory animals are used for regulatory testing to assess the safety, efficacy, and/or potential adverse health effects of new chemicals and products such as vaccines, medicines, food additives, pesticides, and industrial chemicals. Testing results are used for risk assessment decisions intended to safeguard human and animal health. However, chemical toxicity and vaccine testing can cause injury, disease, and mortality involving significant pain and distress. Alleviation of pain and distress in animals during testing is problematic because regulations allow treatment only if the treatment does not interfere with the study. One approach to this problem has been to identify criteria that can serve as the basis for ending a test procedure sooner in an effort to terminate or avoid pain and distress while still allowing attainment of study objectives. These criteria are referred to as humane endpoints because they reduce the severity and/or duration of pain and distress experienced by an animal. New and revised test methods and approaches that incorporate humane endpoints are being considered and adopted by national and international regulatory testing authorities. The prerequisite for adoption of these methods is a determination that the methods have been adequately validated and that they provide equivalent or better information for risk assessment. Further progress in reducing animal pain and distress resulting from regulatory testing is expected as scientific and technological advances are incorporated into testing procedures and strategies.

The Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM): a review of the ICCVAM test method evaluation process and current international collaborations with the European Centre for the Validation of Alternative Methods (ECVAM).

Over the last decade, national authorities in the USA and Europe have launched initiatives to validate new and improved toxicological test methods. In the USA, the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) and its supporting National Toxicology Program Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM) were established by the Federal Government to work with test developers and Federal agencies to facilitate the validation, review, and adoption of new scientifically sound test methods, including alternatives that can refine, reduce, and replace animal use. In Europe, the European Centre for the Validation of Alternative Methods (ECVAM) was established to conduct validation studies on alternative test methods. Despite differences in organisational structure and processes, both organisations seek to achieve the adoption and use of alternative test methods. Accordingly, both have adopted similar validation and regulatory acceptance criteria. Collaborations and processes have also evolved to facilitate the international adoption of new test methods recommended by ECVAM and ICCVAM. These collaborations involve the sharing of expertise and data for test-method workshops and independent scientific peer reviews, and the adoption of processes to expedite the consideration of test methods already reviewed by the other organisation. More recently, NICEATM and ECVAM initiated a joint international validation study on in vitro methods for assessing acute systemic toxicity. These collaborations are expected to contribute to accelerated international adoption of harmonised new test methods that will support improved public health and provide for reduced and more-humane use of laboratory animals.

ECVAM-ICCVAM: prospects for future collaboration.

The level and complexity of testing for hazard and risk assessment of marketed products and environmental agents has increased substantially over time, resulting in the use of greater numbers of both animals and humans for testing. Today, industry and regulatory bodies worldwide face increasing pressures to demonstrate responsible utilisation of laboratory animals, to limit their use, and to employ alternative non-animal tests. Institutions have also been established to identify, encourage development of, conduct research on, and validate new, improved, and surrogate test methods that will reduce and replace animal use. Two such organisations are ECVAM and the Interagency Coordinating Committee for the Validation of Alternative Methods (ICCVAM). As the evolutionary changes occurring in the field of toxicology result in an unprecedented increase in the introduction of alternative methodologies, these will strain the capacities of such alternative methods institutions. That realisation is causing a shift in thinking and creating an impetus to seek approaches by which to collaborate and develop more-efficient operational procedures for the validation and regulatory acceptance of alternative methods. Similarities in objectives, functions, scientific standards, and commitment to the principles of validation and animal welfare support the value of a cooperative arrangement between ECVAM and ICCVAM, to minimise duplication of effort, maximise productivity, and influence the international adoption of alternative tests. Opportunities for ECVAM-ICCVAM collaboration are discussed, which illustrate the feasibility and potential benefits of such a partnership.