What’s all the Squawking About?

Bird Use in Research and Testing

By Penny Hawkins

The use of any species in research and testing presents its own particular ethical and welfare concerns, but bird use is an especially emotive issue for many people. This article presents some factual information on bird experiments, sets out the key concerns, and discusses some future issues. Note that there are no available statistics on bird use in the U.S., as birds bred for research are currently excluded from coverage by the Animal Welfare Act. European figures have been used as an alternative, with additional information from the United Kingdom (UK) statistics wherever these include more detail.

How many birds are used?

Rodents, dogs, and primates are often thought of as ‘typical’ laboratory animals, but birds are also used in relatively large numbers. For example, in the UK in 2004, birds were the third most commonly used animals after rodents and fish,^[1] and a total of 535,000 birds (quail and “others”) were used within the European Union (EU)∗ in 2002.^[2] Assuming that relative species use is broadly similar among different countries, we can estimate that over 240,000 birds are probably used in the U.S. each year.

The UK statistics provide some more detail on the species of birds used. The most recent report (2004) shows that most birds used in research and testing are domestic fowl (89.5 %), 1.5 % are turkeys, 0.5 percent are quail and 8.5 percent are “other” birds. This covers a range of species including pigeons, starlings, finches, and waterfowl, but these are not listed separately.

What kind of procedures are carried out on birds?

Data are available on the broad purposes of bird use within the EU (Figure 1). In 2002 (the most recent year for which statistics have been published), most birds were used in the research and development, production, quality control, or safety testing of human and veterinary medical products. Of these, 82 percent were used in studies relating to animal diseases and 18 percent for human diseases. In the UK, three quarters of domestic fowl are used in applied studies relating to veterinary medicine, particularly parasitology.

Much of this research relates to diseases of farmed fowl, especially coccidiosis and respiratory diseases such as those caused by mycoplasmas and E. coli. These cause significant distress and suffering for farmed and laboratory birds alike. Fowl are adapted to conceal signs of suffering, so it can be very difficult to ensure that the birds used in these tests are euthanased before they begin to suffer substantially. Fowl are also used to develop vaccines against infectious organisms, including Salmonella and Campylobacter, to protect the human food chain.

The largest single category of procedures in which birds were used in the EU in 2002 was fundamental research, for example in physiology studies that aimed to discover how animals function. In the UK, about one fifth of domestic fowl and almost 90 percent of “other” birds are used for this purpose.

Fundamental research using birds often involves surgery (e.g. to implant telemetry devices, trace nerves, or manipulate areas of the brain). Trapping birds from the wild for research is extremely stressful, especially if they are transported to the laboratory for experimental use. Birds used in migration experiments are often confined in funnels for long periods to see which way they orient themselves, which is likely to cause distress if they should be migrating. Birds are also used to study the mechanisms of song. They have been operated on to find out how air flows through their respiratory system when they sing, and what happens if they are deafened or operated on so that they are vocally distorted. These areas of bird research are perhaps the most controversial of all.

In the EU in 2002, almost 19,000 birds were used in toxicology and safety testing, and to evaluate human medical and veterinary products (40 percent), agricultural substances (42 percent), industrial substances (8 percent) and additives for animal feeds (10 percent). Of these tests, 14 percent were Lethal Dose 50 (LD50) tests (whose endpoint occurs when half the test subjects die) or other lethal tests, and 25 percent were acute or subacute tests, which involve giving high doses of the test substance. These are highly likely to cause significant suffering and distress. Birds are also subject to speciesism in vaccine batch safety tests, since 10 are required for each batch of avian vaccine, yet only 2 dogs or pigs are required for vaccines for those species. There is no clear reason for this.

Almost all birds are killed following experiments; there is little potential to rehome or release them apart from some minimally invasive, short-term fundamental experiments using wild birds.

Purposes of bird use in the EU

Figure 1. Purpose of bird use in the European Union, 2002

How are laboratory birds housed?

Much laboratory bird housing is woefully inadequate, both from an animal welfare and a scientific perspective. In the case of the pigeon, the minimum area per bird in the Institute for Laboratory Animal Research Guide is just 0.8 ft², or 11 by 11 inches.^[3] This is not even sufficient room for these highly active and intelligent birds to stretch their wings, let alone perform a range of natural behaviours. Domestic fowl fare no better. For example, the Guide allows fowl up to 1 kg to be housed with 1 ft² of space per bird, while the relevant Council of Europe (CE) Convention permits 1 kg fowl to be group housed with just 0.5 ft² each.^[4]

These very small minimum space allowances clearly do not allow environmental enrichment such as dustbaths and perches to be provided, nor do they allow birds to exercise, forage, or interact socially with one another in an appropriate way. Besides the obvious welfare issues involved, birds kept in such inadequate housing are likely to be highly stressed. This has serious implications for scientific validity, since the stress response affects many different organ systems and physiological parameters.

The CE Convention is currently under revision, and the new proposals for bird husbandry encourage better housing and care that respects birds’ needs more and allow them more opportunities to express a range of natural, species-specific behaviours. Housing in stable, compatible groups is encouraged (for social birds), with environmental enrichment and minimum enclosure sizes of 21.5 ft² for most adult birds, including domestic fowl, smaller turkeys, pigeons, and waterfowl.^[5] The new proposals are better but still represent a compromise position. The RSPCA encourages bird users to recognise that minimum standards are not “good practice” and to adopt good practice guidelines such as those set out by the Joint Working Group on Refinement (JWGR).^[6]

What does the future hold?

The potential to replace birds varies with the different purposes for which they are used. In the case of vaccines, there is unfortunately very limited scope for replacement at the development stage, since so many different organ systems are involved. There are more opportunities to replace animals in vaccine batch testing, and some efforts are being made in this area.

Recent concerns about avian influenza will inevitably lead to more bird experiments. Birds will be used in vaccine development and diagnostic tests, and vaccines against the virus are likely to be grown in eggs. The birds used to produce the eggs will be housed in Specific Pathogen Free conditions, which are often barren and boring in practice (although they do not need to be).

Within toxicity testing, the use of birds in LD50 and acute tests for agricultural substances has been criticised because of species differences, since so many different wild birds are affected. There have been moves towards other tests such as limit tests, which unfortunately do not replace birds but do reduce the numbers and suffering involved.

In the case of fundamental research such as that aiming to discover the physiology of flight and song, the most obvious replacement is not to conduct the research at all; however, this approach is likely to be resisted by the scientists concerned. It is thus very important to ensure that ethics committees and Institutional Animal Care and Use Committees include members with a broad range of interests, including those who can act as advocates for the animals and question the ‘justification’ for and ‘necessity’ of each project.

Of course, in an ideal world, birds (and all other animals) would not be used in experiments at all; but in the meantime, good housing and care can make a huge, positive impact on their welfare and quality of life. The RSPCA hopes that the proposals for the European Convention will be accepted and used to encourage even better practice and that the forthcoming revision of the ILAR Guide will also represent real improvements for birds for as long as their use continues.

Resources

[1] Home Office (2005). Statistics of Scientific Procedures on Living Animals: Great Britain 2004. London: HMSO.
[2] Commission of the European Communities (2005). Fourth Report on the Statistics on the Number of Animals used for Experimental and Other Scientific Purposes in the Member States of the European Union. Brussels: EC.
[3] ILAR (1996). Guide for the Care and Use of Laboratory Animals. Washington. DC: National Academy Press.
[4] Council of Europe (1986). European Convention for the Protection of Vertebrate Animals Used for Experimental and Other Scientific Purposes. ETS123. Strasbourg: Council of Europe.
[5] Council of Europe Working Group on Birds (2003). Species-specific Provisions for Birds: Background Information for the Proposals Presented by the Group of Experts on Birds. Strasbourg: Council of Europe.
[6] Hawkins P. et al. (2001). Laboratory birds: Refinements in husbandry and procedures. Laboratory Animals 35 (Suppl 1): 1-163.

Hawkins, Penny. (Spring 2006). AV Magazine. Pages 24-26.

Print View

Web ViewText Size: