Search This Blog

Wednesday, April 30, 2025

Animal welfare

From Wikipedia, the free encyclopedia
Animal welfare
A four-week-old puppy, found alongside a road after flooding in West Virginia, United States, is fed at an Emergency Animal Rescue Service shelter in the Twin Falls State Park.

Animal welfare is the well-being of non-human animals. Formal standards of animal welfare vary between contexts, but are debated mostly by animal welfare groups, legislators, and academics. Animal welfare science uses measures such as longevity, disease, immunosuppression, behavior, physiology, and reproduction, although there is debate about which of these best indicate animal welfare.

Respect for animal welfare is often based on the belief that nonhuman animals are sentient and that consideration should be given to their well-being or suffering, especially when they are under the care of humans. These concerns can include how animals are slaughtered for food, how they are used in scientific research, how they are kept (as pets, in zoos, farms, circuses, etc.), and how human activities affect the welfare and survival of wild species.

There are two forms of criticism of the concept of animal welfare, coming from diametrically opposite positions. One view, held by some thinkers in history, holds that humans have no duties of any kind to animals. The other view is based on the animal rights position that animals should not be regarded as property and any use of animals by humans is unacceptable. Accordingly, some animal rights proponents argue that the perception of better animal welfare facilitates continued and increased exploitation of animals. Some authorities therefore treat animal welfare and animal rights as two opposing positions Others see animal welfare gains as incremental steps towards animal rights.

The predominant view of modern neuroscientists, notwithstanding philosophical problems with the definition of consciousness even in humans, is that consciousness exists in nonhuman animals;however, some still maintain that consciousness is a philosophical question that may never be scientifically resolved. A new study has devised a unique way to dissociate conscious from nonconscious perception in animals. The researchers built experiments predicting opposite behavioral outcomes to consciously vs. non-consciously perceived stimuli. The monkeys' behaviors displayed these exact opposite signatures, just like aware and unaware humans tested in the study.

History, principles, and practice

Animal protection laws were enacted as early as the 1st millennium BCE in India. Several Indian kings built hospitals for animals, and emperor Ashoka (304–232 BCE) issued orders against hunting and animal slaughter, in line with ahimsa, the doctrine of non-violence. In the 13th century CE, Genghis Khan protected wildlife in Mongolia during the breeding season (March to October).

Early legislation in the Western world on behalf of animals includes the Ireland Parliament (Thomas Wentworth) "An Act against Plowing by the Tayle, and pulling the Wooll off living Sheep", 1635, and the Massachusetts Colony (Nathaniel Ward) "Off the Bruite Creatures" Liberty 92 and 93 in the "Massachusetts Body of Liberties" of 1641. In the Edo period of Japan, Tokugawa Tsunayoshi (1646 - 1709) instituted several laws relating to animal welfare, particularly towards dogs, earning him the nickname of "the dog Shogun".

In 1776, English clergyman Humphrey Primatt authored A Dissertation on the Duty of Mercy and Sin of Cruelty to Brute Animals, one of the first books published in support of animal welfare. Marc Bekoff said that "Primatt was largely responsible for bringing animal welfare to the attention of the general public."

Since 1822, when Irish MP Richard Martin brought the "Cruel Treatment of Cattle Act 1822" through Parliament offering protection from cruelty to cattle, horses, and sheep, an animal welfare movement has been active in England. Martin was among the founders of the world's first animal welfare organization, the Society for the Prevention of Cruelty to Animals, or SPCA, in 1824. In 1840, Queen Victoria gave the society her blessing, and it became the RSPCA. The society used members' donations to employ a growing network of inspectors, whose job was to identify abusers, gather evidence, and report them to the authorities.

In 1837, the German minister Albert Knapp founded the first German animal welfare society.

One of the first national laws to protect animals was the UK Cruelty to Animals Act 1835 followed by the Protection of Animals Act 1911. In the US it was many years until there was a national law to protect animals—the Animal Welfare Act of 1966—although there were a number of states that passed anti-cruelty laws between 1828 and 1898. In India, animals are protected by the "Prevention of Cruelty to Animals Act, 1960".

Significant progress in animal welfare did not take place until the late 20th century. In 1965, the UK government commissioned an investigation—led by professor Roger Brambell—into the welfare of intensively farmed animals, partly in response to concerns raised in Ruth Harrison's 1964 book, Animal Machines. On the basis of Brambell's report, the UK government set up the Farm Animal Welfare Advisory Committee in 1967, which became the Farm Animal Welfare Council in 1979. The committee's first guidelines recommended that animals require the freedom to "stand up, lie down, turn around, groom themselves and stretch their limbs." The guidelines have since been elaborated upon to become known as the Five Freedoms.

In the UK, the Animal Welfare Act 2006 (c. 45) consolidated many different forms of animal welfare legislation.

A number of animal welfare organisations are campaigning to achieve a Universal Declaration on Animal Welfare (UDAW) at the United Nations. In principle, the Universal Declaration would call on the United Nations to recognise animals as sentient beings, capable of experiencing pain and suffering, and to recognise that animal welfare is an issue of importance as part of the social development of nations worldwide. The campaign to achieve the UDAW is being coordinated by World Animal Protection, with a core working group including Compassion in World Farming, the RSPCA, and the Humane Society International (the international branch of HSUS).

The 2019 UN Global Sustainable Development Report identified animal welfare as one of several key missing issues in the 2030 Agenda for Sustainable Development.

Animal welfare science

Animal welfare science is an emerging field that seeks to answer questions raised by the keeping and use of animals, such as whether hens are frustrated when confined in cages, whether the psychological well-being of animals in laboratories can be maintained, and whether zoo animals are stressed by the transport required for international conservation. Ireland leads research into farm animal welfare with the recently published Research Report on Farm Animal Welfare Archived 8 May 2019 at the Wayback Machine.

Animal welfare issues

Farmed animals

The welfare of egg laying hens in battery cages (top) can be compared with the welfare of free range hens (middle and bottom) which are given access to the outdoors. However, animal welfare groups argue that the vast majority of free-range hens are still intensively confined (bottom) and are rarely able to go outdoors.

A major concern for the welfare of farmed animals is factory farming in which large numbers of animals are reared in confinement at high stocking densities. Issues include the limited opportunities for natural behaviors, for example, in battery cages, veal and gestation crates, instead producing abnormal behaviors such as tail-biting, cannibalism, and feather pecking, and routine invasive procedures such as beak trimming, castration, and ear notching.More extensive methods of farming, e.g. free range, can also raise welfare concerns such as the mulesing of sheep and predation of stock by wild animals. Biosecurity is also a risk with free range farming, as it allows for more contact between livestock and wild animal populations, which may carry zoonoses.

Farmed animals are artificially selected for production parameters which sometimes impinge on the animals' welfare. For example, broiler chickens are bred to be very large to produce the greatest quantity of meat per animal. Broilers bred for fast growth have a high incidence of leg deformities because the large breast muscles cause distortions of the developing legs and pelvis, and the birds cannot support their increased body weight. As a consequence, they frequently become lame or suffer from broken legs. The increased body weight also puts a strain on their hearts and lungs, and ascites often develop. In the UK alone, up to 20 million broilers each year die from the stress of catching and transporting before reaching the slaughterhouse.This stress can be measured by the high level of heart rate and its cortisol levels, but it can also be seen in their behavior or physical changes. In situations where they are threatened, alone, or can't interact with others, these results are common. Animal welfare violations have been observed more in intensively bred chicken, pig and cattle species, respectively, and studies and laws have been enacted in this regard. However, animal welfare in semi-intensive species such as sheep and goats is nowadays being scrutinised and gaining importance.

Another concern about the welfare of farmed animals is the method of slaughter, especially ritual slaughter. While the killing of animals need not necessarily involve suffering, the general public considers that killing an animal reduces its welfare. This leads to further concerns about premature slaughtering such as chick culling by the laying hen industry, in which males are slaughtered immediately after hatching because they are superfluous; this policy occurs in other farmed animal industries such as the production of goat and cattle milk, raising the same concerns.

A 2023 report by the Animal Welfare Institute found that animal welfare claims by companies selling meat and poultry products lack adequate substantiation in roughly 85% of analyzed cases.

Cetaceans

Captive cetaceans are kept for display, research and naval operations. To enhance their welfare, humans feed them fish that are dead but are disease-free, protect them from predators and injury, monitor their health, and provide activities for behavioral enrichment. Some are kept in lagoons with natural soil and vegetated sides. Most are in concrete tanks which are easy to clean but echo their natural sounds back to them. They cannot develop their own social groups, and related cetaceans are typically separated for display and breeding. Military dolphins used in naval operations swim free during operations and training and return to pens otherwise. Captive cetaceans are trained to present themselves for blood samples, health exams, and noninvasive breath samples above their blow holes. Staff can monitor the captives afterward for signs of infection from the procedure.

Research on wild cetaceans leaves them free to roam and make sounds in their natural habitat, eat live fish, face predators and injury, and form social groups voluntarily. However, boat engines of researchers, whale watchers and others add substantial noise to their natural environment, reducing their ability to echolocate and communicate. Electric engines are far quieter, but are not widely used for either research or whale watching, even for maintaining position, which does not require much power. Vancouver Port offers discounts for ships with quiet propeller and hull designs. Other areas have reduced speeds. Boat engines also have unshielded propellers, which cause serious injuries to cetaceans who come close to the propeller. The US Coast Guard has proposed rules on propeller guards to protect human swimmers, but has not adopted any rules. The US Navy uses propeller guards to protect manatees in Georgia. Ducted propellers provide more efficient drive at speeds up to 10 knots, and protect animals beneath and beside them, but need grilles to prevent injuries to animals drawn into the duct. Attaching satellite trackers and obtaining biopsies to measure pollution loads and DNA involve either capture and release, or shooting the cetaceans from a distance with dart guns. A cetacean was killed by a fungal infection after being darted, due to either an incompletely sterilized dart or an infection from the ocean entering the wound caused by the dart.[59] Researchers on wild cetaceans have not yet been able to use drones to capture noninvasive breath samples.

Other harms to wild cetaceans include commercial whaling, aboriginal whaling, drift netting, ship collisions, water pollution, noise from sonar and reflection seismology, predators, loss of prey, and disease. Efforts to enhance the life of wild cetaceans, besides reducing those harms, include offering human music. Canadian rules do not forbid playing quiet music, though they forbid "noise that may resemble whale songs or calls, underwater".

Wild animal welfare

In addition to cetaceans, the welfare of other wild animals has also been studied, though to a lesser extent than that of animals in farms. Research in wild animal welfare has two focuses: the welfare of wild animals kept in captivity and the welfare of animals living in the wild. The former has addressed the situation of animals kept both for human use, as in zoos or circuses, or in rehabilitation centers. The latter has examined how the welfare of non-domesticated animals living in wild or urban areas are affected by humans or natural factors causing wild animal suffering.

Some of the proponents of these views have advocated carrying out conservation efforts in ways that respect the welfare of wild animals, within the framework of the disciplines of compassionate conservation and conservation welfare, while others have argued in favor of improving the welfare of wild animals for the sake of the animals, regardless of whether there are any conservation issues involved at all. The welfare economist Yew-Kwang Ng, in his 1995 "Towards welfare biology: Evolutionary economics of animal consciousness and suffering", proposed welfare biology as a research field to study "living things and their environment with respect to their welfare (defined as net happiness, or enjoyment minus suffering)."

Legislation

European Union

The European Commission's activities in this area start with the recognition that animals are sentient beings. The general aim is to ensure that animals do not endure avoidable pain or suffering, and obliges the owner/keeper of animals to respect minimum welfare requirements. European Union legislation regarding farm animal welfare is regularly re-drafted according to science-based evidence and cultural views. For example, in 2009, legislation was passed which aimed to reduce animal suffering during slaughter and on 1 January 2012, the European Union Council Directive 1999/74/EC came into act, which means that conventional battery cages for laying hens are now banned across the Union.

United Kingdom

The Animal Welfare Act 2006 makes owners and keepers responsible for ensuring that the welfare needs of their animals are met. These include the need: for a suitable environment (place to live), for a suitable diet, to exhibit normal behavior patterns, to be housed with, or apart from, other animals (if applicable), and to be protected from pain, injury, suffering and disease. Anyone who is cruel to an animal, or does not provide for its welfare needs, may be banned from owning animals, fined up to £20,000 and/or sent to prison for a maximum of six months.

In the UK, the welfare of research animals being used for "regulated procedures" was historically protected by the Animals (Scientific Procedures) Act 1986 (ASPA) which is administrated by the Home Office. The Act defines "regulated procedures" as animal experiments that could potentially cause "pain, suffering, distress or lasting harm" to "protected animals". Initially, "protected animals" encompassed all living vertebrates other than humans, but, in 1993, an amendment added a single invertebrate species, the common octopus.

Primates, cats, dogs, and horses have additional protection over other vertebrates under the Act. Revised legislation came into force in January 2013. This has been expanded to protect "...all living vertebrates, other than man, and any living cephalopod. Fish and amphibia are protected once they can feed independently and cephalopods at the point when they hatch. Embryonic and foetal forms of mammals, birds and reptiles are protected during the last third of their gestation or incubation period." The definition of regulated procedures was also expanded: "A procedure is regulated if it is carried out on a protected animal and may cause that animal a level of pain, suffering, distress or lasting harm equivalent to, or higher than, that caused by inserting a hypodermic needle according to good veterinary practice." It also includes modifying the genes of a protected animal if this causes the animal pain, suffering, distress, or lasting harm. The ASPA also considers other issues such as animal sources, housing conditions, identification methods, and the humane killing of animals.

Those applying for a license must explain why such research cannot be done through non-animal methods. The project must also pass an ethical review panel which aims to decide if the potential benefits outweigh any suffering for the animals involved.

United States

In the United States, a federal law called the Humane Slaughter Act was designed to decrease suffering of livestock during slaughter.

The Georgia Animal Protection Act of 1986 was a state law enacted in response to the inhumane treatment of companion animals by a pet store chain in Atlanta. The Act provided for the licensing and regulation of pet shops, stables, kennels, and animal shelters, and established, for the first time, minimum standards of care. Additional provisions, called the Humane Euthanasia Act, were added in 1990, and then further expanded and strengthened with the Animal Protection Act of 2000.

In 2002, voters passed (by a margin of 55% for and 45% against) Amendment 10 to the Florida Constitution banning the confinement of pregnant pigs in gestation crates. In 2006, Arizona voters passed Proposition 204 with 62% support; the legislation prohibits the confinement of calves in veal crates and breeding sows in gestation crates. In 2007, the Governor of Oregon signed legislation prohibiting the confinement of pigs in gestation crates and in 2008, the Governor of Colorado signed legislation that phased out both gestation crates and veal crates. Also during 2008, California passed Proposition 2, known as the "Prevention of Farm Animal Cruelty Act", which orders new space requirements for farm animals starting in 2015.

The use of animals in laboratories remains controversial. Animal welfare advocates push for enforced standards to ensure the health and safety of those animals used for tests.

In the US, every institution that uses vertebrate animals for federally funded laboratory research must have an Institutional Animal Care and Use Committee (IACUC). Each local IACUC reviews research protocols and conducts evaluations of the institution's animal care and use which includes the results of inspections of facilities that are required by law. The IACUC committee must assess the steps taken to "enhance animal well-being" before research can take place. This includes research on farm animals.

According to the National Institutes of Health Office of Laboratory Animal Welfare, researchers must try to minimize distress in animals whenever possible: "Animals used in research and testing may experience pain from induced diseases, procedures, and toxicity. The Public Health Service (PHS) Policy and Animal Welfare Regulations (AWRs) state that procedures that cause more than momentary or slight pain or distress should be performed with appropriate sedation, analgesia, or anesthesia.

However, research and testing studies sometimes involve pain that cannot be relieved with such agents because they would interfere with the scientific objectives of the study. Accordingly, federal regulations require that IACUCs determine that discomfort to animals will be limited to that which is unavoidable for the conduct of scientifically valuable research, and that unrelieved pain and distress will only continue for the duration necessary to accomplish the scientific objectives. The PHS Policy and AWRs further state that animals that would otherwise suffer severe or chronic pain and distress that cannot be relieved should be painlessly killed at the end of the procedure, or if appropriate, during the procedure."

The National Research Council's Guide for the Care and Use of Laboratory Animals also serves as a guide to improve welfare for animals used in research in the US. The Federation of Animal Science Societies' Guide for the Care and Use of Agricultural Animals in Research and Teaching is a resource addressing welfare concerns in farm animal research.

Laboratory animals in the US are also protected under the Animal Welfare Act. The United States Department of Agriculture Animal and Plant Health Inspection Service (APHIS) enforces the Animal Welfare Act. APHIS and USDA help the animal welfare act by creating and updating new rules in the AWA regulations, licensing and checking in facilities, doing investigations for potential violations, and making sure everyone stays in line with the law.APHIS inspects animal research facilities regularly and reports are published online.

According to the U.S. Department of Agriculture (USDA), the total number of animals used in the U.S. in 2005 was almost 1.2 million, but this does not include rats, mice, and birds which are not covered by welfare legislation but make up approximately 90% of research animals.

Approaches and definitions

There are many different approaches to describing and defining animal welfare.

Positive conditions – Providing good animal welfare is sometimes defined by a list of positive conditions which should be provided to the animal. This approach is taken by the Five Freedoms and the three principles of professor John Webster.

The Five Freedoms are:

  • Freedom from thirst and hunger – by ready access to fresh water and a diet to maintain full health and vigour
  • Freedom from discomfort – by providing an appropriate environment including shelter and a comfortable resting area
  • Freedom from pain, injury, and disease – by prevention or rapid diagnosis and treatment
  • Freedom to express most normal behavior – by providing sufficient space, proper facilities, and company of the animal's own kind
  • Freedom from fear and distress – by ensuring conditions and treatment which avoid mental suffering

John Webster defines animal welfare by advocating three positive conditions: Living a natural life, being fit and healthy, and being happy.

High production – In the past, many have seen farm animal welfare chiefly in terms of whether the animal is producing well. The argument is that an animal in poor welfare would not be producing well, however, many farmed animals will remain highly productive despite being in conditions where good welfare is almost certainly compromised, e.g., layer hens in battery cages.

Emotion in animals – Others in the field, such as professor Ian Duncan and professor Marian Dawkins, focus more on the feelings of the animal. This approach indicates the belief that animals should be considered as sentient beings. Duncan wrote, "Animal welfare is to do with the feelings experienced by animals: the absence of strong negative feelings, usually called suffering, and (probably) the presence of positive feelings, usually called pleasure. In any assessment of welfare, it is these feelings that should be assessed." Dawkins wrote, "Let us not mince words: Animal welfare involves the subjective feelings of animals."

Welfare biologyYew-Kwang Ng defines animal welfare in terms of welfare economics: "Welfare biology is the study of living things and their environment with respect to their welfare (defined as net happiness, or enjoyment minus suffering). Despite difficulties of ascertaining and measuring welfare and relevancy to normative issues, welfare biology is a positive science."

Dictionary definition – In the Saunders Comprehensive Veterinary Dictionary, animal welfare is defined as "the avoidance of abuse and exploitation of animals by humans by maintaining appropriate standards of accommodation, feeding and general care, the prevention and treatment of disease and the assurance of freedom from harassment, and unnecessary discomfort and pain."

American Veterinary Medical Association (AVMA) has defined animal welfare as: "An animal is in a good state of welfare if (as indicated by scientific evidence) it is healthy, comfortable, well nourished, safe, able to express innate behavior, and if it is not suffering from unpleasant states such as pain, fear, and distress." They have offered the following eight principles for developing and evaluating animal welfare policies.

  • The responsible use of animals for human purposes, such as companionship, food, fiber, recreation, work, education, exhibition, and research conducted for the benefit of both humans and animals, is consistent with the Veterinarian's Oath.
  • Decisions regarding animal care, use, and welfare shall be made by balancing scientific knowledge and professional judgment with consideration of ethical and societal values.
  • Animals must be provided water, food, proper handling, health care, and an environment appropriate to their care and use, with thoughtful consideration for their species-typical biology and behavior.
  • Animals should be cared for in ways that minimize fear, pain, stress, and suffering.
  • Procedures related to animal housing, management, care, and use should be continuously evaluated, and when indicated, refined or replaced.
  • Conservation and management of animal populations should be humane, socially responsible, and scientifically prudent.
  • Animals shall be treated with respect and dignity throughout their lives and, when necessary, provided a humane death.
  • The veterinary profession shall continually strive to improve animal health and welfare through scientific research, education, collaboration, advocacy, and the development of legislation and regulations.

Terrestrial Animal Health Code of World Organisation for Animal Health defines animal welfare as "how an animal is coping with the conditions in which it lives. An animal is in a good state of welfare if (as indicated by scientific evidence) it is healthy, comfortable, well nourished, safe, able to express innate behaviour, and if it is not suffering from unpleasant states such as pain, fear, and distress. Good animal welfare requires disease prevention and veterinary treatment, appropriate shelter, management, nutrition, humane handling and humane slaughter/killing. Animal welfare refers to the state of the animal; the treatment that an animal receives is covered by other terms such as animal care, animal husbandry, and humane treatment."

Coping – Professor Donald Broom defines the welfare of an animal as "Its state as regards its attempts to cope with its environment. This state includes how much it is having to do to cope, the extent to which it is succeeding in or failing to cope, and its associated feelings." He states that "welfare will vary over a continuum from very good to very poor and studies of welfare will be most effective if a wide range of measures is used." John Webster criticized this definition for making "no attempt to say what constitutes good or bad welfare."

Attitudes

Animal welfare often refers to a utilitarian attitude towards the well-being of nonhuman animals. It believes the animals can be exploited if the animal suffering and the costs of use is less than the benefits to humans. This attitude is also known simply as welfarism.

An example of welfarist thought is Hugh Fearnley-Whittingstall's meat manifesto. Point three of eight is:

Think about the animals that the meat you eat comes from. Are you at all concerned about how they have been treated? Have they lived well? Have they been fed on safe, appropriate foods? Have they been cared for by someone who respects them and enjoys contact with them? Would you like to be sure of that? Perhaps it's time to find out a bit more about where the meat you eat comes from. Or to buy from a source that reassures you about these points.

Robert Garner describes the welfarist position as the most widely held in modern society. He states that one of the best attempts to clarify this position is given by philosopher Robert Nozick:

Consider the following (too minimal) position about the treatment of animals. So that we can easily refer to it, let us label this position "utilitarianism for animals, Kantianism for people." It says: (1) maximize the total happiness of all living beings; (2) place stringent side constraints on what one may do to human beings. Human beings may not be used or sacrificed for the benefit of others; animals may be used or sacrificed for the benefit of other people or animals only if those benefits are greater than the loss inflicted.

Welfarism is often contrasted with the animal rights and animal liberation positions, which hold that animals should not be used by humans and should not be regarded as human property.However, it has been argued that both welfarism and animal liberation only make sense if it is assumed that animals have "subjective welfare".

New welfarism

New welfarism was coined by Gary L. Francione in 1996. It is a view that the best way to prevent animal suffering is to abolish the causes of animal suffering, but advancing animal welfare is a goal to pursue in the short term. Thus, for instance, new welfarists want to phase out fur farms and animal experiments but in the short-term they try to improve conditions for the animals in these systems, so they lobby to make cages less constrictive and to reduce the numbers of animals used in laboratories.

Within the context of animal research, many scientific organisations believe that improved animal welfare will provide improved scientific outcomes. If an animal in a laboratory is suffering stress or pain it could negatively affect the results of the research.If a researcher wants to conduct an experiment, they must meet up with the 3R’s (replacement, reduction, and refinement). They must show how they’re going to put their plan into action. The ethics committee are to review the plan and check if all principles are being followed and ensure the benefits justify the harm of these animals. The 3R’s are meant to lessen the use of animals in research and lessen any suffering.

Increased affluence in many regions for the past few decades afforded consumers the disposable income to purchase products from high welfare systems. The adaptation of more economically efficient farming systems in these regions were at the expense of animal welfare and to the financial benefit of consumers, both of which were factors in driving the demand for higher welfare for farm animals. A 2006 survey concluded that a majority (63%) of EU citizens "show some willingness to change their usual place of shopping in order to be able to purchase more animal welfare-friendly products."

The volume of scientific research on animal welfare has also increased significantly in some countries.

Criticisms

Denial of duties to animals

Some individuals in history have, at least in principle, rejected the view that humans have duties of any kind to animals.

Augustine of Hippo seemed to take such a position in his writings against those he saw as heretics: "For we see and hear by their cries that animals die with pain, although man disregards this in a beast, with which, as not having a rational soul, we have no community of rights."

Animal rights

American philosopher Tom Regan has criticized the animal welfare movement for not going far enough to protect animals' interests.

Animal rights advocates, such as Gary L. Francione and Tom Regan, argue that the animal welfare position (advocating for the betterment of the condition of animals, but without abolishing animal use) is inconsistent in logic and ethically unacceptable. Philosopher Steven Best suggests that an emphasis on "welfarism" has the effect of legitimizing "any human use of animals" so long as humans aren't "cruel" to them and do whatever is necessary to avoid inflicting "unnecessary harm". Sociologist David Nibert writes that animal welfare reforms, usually implemented by wealthier countries, are often "modest" and "mostly localized," and are vastly surpassed by the ongoing expansion of the capitalist–driven animal–industrial complex, with the number of concentrated animal feeding operations and the animals to fill them dramatically increasing, along with growing numbers of humans consuming animal products.[128][129] However, there are some animal right groups, such as PETA, which support animal welfare measures in the short term to alleviate animal suffering until all animal use is ended.

According to PETA's Ingrid Newkirk in an interview with Wikinews, there are two issues in animal welfare and animal rights. "If I only could have one thing, it would be to end suffering", said Newkirk. "If you could take things from animals and kill animals all day long without causing them suffering, then I would take it... Everybody should be able to agree that animals should not suffer if you kill them or steal from them by taking the fur off their backs or take their eggs, whatever. But you shouldn't put them through torture to do that."

Abolitionism holds that focusing on animal welfare not only fails to challenge animal suffering, but may actually prolong it by making the exercise of property rights over animals appear less unattractive. The abolitionists' objective is to secure a moral and legal paradigm shift, whereby animals are no longer regarded as property. In recent years documentaries such as watchdominion.com have been produced, exposing the suffering occurring in animal agriculture facilities that are marketed as having high welfare standards.

Animal welfare organizations

Global

World Animal Protection was founded in 1981 to protect animals around the globe.

World Organisation for Animal Health (OIE): The intergovernmental organisation responsible for improving animal health worldwide. The OIE has been established "for the purpose of projects of international public utility relating to the control of animal diseases, including those affecting humans and the promotion of animal welfare and animal production food safety."

World Animal Protection: Protects animals across the globe. World Animal Protection's objectives include helping people understand the critical importance of good animal welfare, encouraging nations to commit to animal-friendly practices, and building the scientific case for the better treatment of animals. They are global in a sense that they have consultative status at the Council of Europe and collaborate with national governments, the United Nations, the Food and Agriculture Organization and the World Organization for Animal Health.

Non-government organizations

Animal Welfare Institute (AWI): An American non-profit charitable organization founded by Christine Stevens in 1951 with the goal of reducing suffering inflicted on animals by humans. It is one of the oldest animal welfare organizations in the US.

Canadian Council on Animal Care: The national organization responsible for overseeing the care and use of animals involved in Canadian Science.

Canadian Federation of Humane Societies (CFHS): The only national organization representing humane societies and SPCAs in Canada. They provide leadership on animal welfare issues and spread the message across Canada.

The Canadian Veterinary Medical Association: Brings in veterinary involvement to animal welfare. Their objective is to share this concern of animals with all members of the profession, with the general public, with government at all levels, and with other organizations such as the CFHS, which have similar concerns.

Compassion in World Farming: Founded over 40 years ago in 1967 by a British farmer who became horrified by the development of modern, intensive factory farming. "Today we campaign peacefully to end all cruel factory farming practices. We believe that the biggest cause of cruelty on the planet deserves a focused, specialised approach – so we only work on farm animal welfare."

FarmKind: Raises funds for animal welfare organizations working to reform or end factory farming (specifically, The Humane League, The Good Food Institute, Sinergia Animal, Dansk Vegetarisk Forening, Fish Welfare Initiative and Shrimp Welfare Project - all of which have been recommended by Animal Charity Evaluators. They function as a donation guide for those seeking to help animals as much as possible with their donations.

The Movement for Compassionate Living: Exists to- "Promote simple vegan living and self-reliance as a remedy against the exploitation of humans, animals and the Earth. Promote the use of trees and vegan-organic farming to meet the needs of society for food and natural resources. Promote a land-based society where as much of our food and resources as possible are produced locally."

National Animal Interest Alliance: An animal welfare organization in the United States founded in 1991 promotes the welfare of animals, strengthens the human-animal bond, and safeguards the rights of responsible animal owners, enthusiasts and professionals through research, public information and sound public policy. They host an online library of information about various animal-related subjects serving as a resource for groups and individuals dedicated to responsible animal care and well-being.

National Farm Animal Care Council: Their objectives are to facilitate collaboration among members with respect to farm animal care issues in Canada, to facilitate information sharing and communication, and to monitor trends and initiatives in both the domestic and international market place.

National Office of Animal Health: A British organisation that represents its members drawn from the animal medicines industry.

Ontario Society for the Prevention of Cruelty to Animals: A registered charity comprising over 50 communities.

Royal Society for the Prevention of Cruelty to Animals: A well-known animal welfare charity in England and Wales, founded in 1824.

Universities Federation for Animal Welfare: A UK registered charity, established in 1926, that works to develop and promote improvements in the welfare of all animals through scientific and educational activity worldwide.

Blindsight

From Wikipedia, the free encyclopedia

Blindsight is the ability of people who are cortically blind to respond to visual stimuli that they do not consciously see due to lesions in the primary visual cortex, also known as the striate cortex or Brodmann Area 17.[1] The term was coined by Lawrence Weiskrantz and his colleagues in a paper published in a 1974 issue of Brain.[2] A previous paper studying the discriminatory capacity of a cortically blind patient was published in Nature in 1973.[3] The assumed existence of blindsight is controversial, with some arguing that it is merely degraded conscious vision.[4][5][6]

Type classification

The majority of studies on blindsight are conducted on patients who are hemianopic, i.e. blind in one-half of their visual field. Following the destruction of the left or right striate cortex, patients are asked to detect, localize, and discriminate amongst visual stimuli that are presented to their blind side, often in a forced-response or guessing situation, even though they may not consciously recognize the visual stimulus. Research shows that such blind patients may achieve a higher accuracy than would be expected from chance alone.

Type 1 blindsight is the term given to this ability to guess—at levels significantly above chance—aspects of a visual stimulus (such as location or type of movement) without any conscious awareness of any stimuli. Type 2 blindsight occurs when patients claim to have a feeling that there has been a change within their blind area—e.g. movement—but that it was not a visual percept. The re-classification of blindsight into Type 1 and Type 2 was made after it was shown that the most celebrated blindsight patient, "GY", was usually conscious of stimuli presented to his blind field if the stimuli had certain specific characteristics, namely being of high contrast and moving fast (at speeds in excess of 20 degrees per second).

In the aftermath of the First World War, a neurologist, George Riddoch, had described patients who had been blinded by gunshot wounds to V1, who could not see stationary objects but who were, as he reported, "conscious" of seeing moving objects in their blind field. It is for this reason that the phenomenon has more recently also been called the Riddoch syndrome.

Since then it has become apparent that such subjects can also become aware of visual stimuli belonging to other visual domains, such as color and luminance, when presented to their blind fields. The ability of such hemianopic subjects to become consciously aware of stimuli presented to their blind field is also commonly referred to as "residual" or "degraded" vision.

As originally defined, blindsight challenged the common belief that perceptions must enter consciousness to affect our behavior, by showing that our behavior can be guided by sensory information of which we have no conscious awareness. Since the demonstration that blind patients can experience some visual stimuli consciously, and the consequent redefinition of blindsight into Type 1 and Type 2, a more nuanced view of the phenomenon has developed. Blindsight may be thought of as a converse of the form of anosognosia known as Anton syndrome, in which there is full cortical blindness along with the confabulation of visual experience.

History

Much of our current understanding of blindsight can be attributed to early experiments on monkeys. One monkey, named Helen, could be considered the "star monkey in visual research" because she was the original blindsight subject. Helen was a macaque monkey that had been decorticated; specifically, her primary visual cortex (V1) was completely removed, blinding her. Nevertheless, under certain specific situations, Helen exhibited sighted behavior. Her pupils would dilate and she would blink at stimuli that threatened her eyes. Furthermore, under certain experimental conditions, she could detect a variety of visual stimuli, such as the presence and location of objects, as well as shape, pattern, orientation, motion, and color. In many cases, she was able to navigate her environment and interact with objects as if she were sighted.

A similar phenomenon was also discovered in humans. Subjects who had suffered damage to their visual cortices due to accidents or strokes reported partial or total blindness. Despite this, when prompted they could "guess" the presence and details of objects with above-average accuracy and, much like animal subjects, could catch objects tossed at them. The subjects never developed any kind of confidence in their abilities. Even when told of their successes, they would not begin to spontaneously make "guesses" about objects, but instead still required prompting. Furthermore, blindsight subjects rarely express the amazement about their abilities that sighted people would expect them to express.

Describing blindsight

Patients with blindsight have damage to the system that produces visual perception (the visual cortex of the brain and some of the nerve fibers that bring information to it from the eyes) rather than to the underlying brain system controlling eye movements. The phenomenon was originally thought to show how, after the more complex perception system is damaged, people can use the underlying control system to guide hand movements towards an object even though they cannot see what they are reaching for. Hence, visual information can control behavior without producing a conscious sensation. This ability of those with blindsight to act as if able to see objects that they are unconscious of suggested that consciousness is not a general property of all parts of the brain, but is produced by specialized parts of it.

Blindsight patients show awareness of single visual features, such as edges and motion, but cannot gain a holistic visual percept. This suggests that perceptual awareness is modular and that—in sighted individuals—there is a "binding process that unifies all information into a whole percept", which is interrupted in patients with such conditions as blindsight and visual agnosia. Therefore, object identification and object recognition are thought to be separate processes and occur in different areas of the brain, working independently from one another. The modular theory of object perception and integration would account for the "hidden perception" experienced in blindsight patients. Research has shown that visual stimuli with the single visual features of sharp borders, sharp onset/offset times, motion and low spatial frequency contribute to, but are not strictly necessary for, an object's salience in blindsight.

Cause

There are multiple theories about what causes blindsight. The first states that after damage to area V1, other branches of the optic nerve deliver visual information to the superior colliculus, pulvinar and several other areas, including parts of the cerebral cortex. In turn, these areas might then control the blindsight responses.

Another explanation for the phenomenon of blindsight is that even though the majority of a person's visual cortex may be damaged, tiny islands of functioning tissue remain. These islands are not large enough to provide conscious perception, but nevertheless enough for some unconscious visual perception.

A third theory is that the information required to determine the distance to and velocity of an object in object space is determined by the lateral geniculate nucleus (LGN) before the information is projected to the visual cortex. In a normal subject, these signals are used to merge the information from the eyes into a three-dimensional representation (which includes the position and velocity of individual objects relative to the organism), extract a vergence signal to benefit the precision (previously auxiliary) optical system, and extract a focus control signal for the lenses of the eyes. The stereoscopic information is attached to the object information passed to the visual cortex.

More recently, with the demonstration of a direct input from the LGN to area V5 (MT), which delivers signals from fast moving stimuli at latencies of about 30 ms, another explanation has emerged. This one proposes that the delivery of these signals is sufficient to arouse a conscious experience of fast visual motion, without implying that it is V5 alone that is responsible, since once signals reach V5, they may be propagated to other areas of the brain. The latter account would seem to exclude the possibility that signals are "pre-processed" by V1 or "post-processed" by it (through return connections from V5 back to V1), as has been suggested. The pulvinar nucleus of the thalamus also sends direct, V1 by-passing, signals to V5 but their precise role in generating a conscious visual experience of motion has not yet been determined.

Evidence of blindsight can be indirectly observed in children as young as two months, although there is difficulty in determining the type in a patient who is not old enough to answer questions.

Evidence in animals

In a 1995 experiment, researchers attempted to show that monkeys with lesions in or even wholly removed striate cortexes also experienced blindsight. To study this, they had the monkeys complete tasks similar to those commonly used for human subjects. The monkeys were placed in front of a monitor and taught to indicate whether a stationary object or nothing was present in their visual field when a tone was played. Then the monkeys performed the same task except the stationary objects were presented outside of their visual field. The monkeys performed very similar to human participants and were unable to perceive the presence of stationary objects outside of their visual field.

Another 1995 study by the same group sought to prove that monkeys could also be conscious of movement in their deficit visual field despite not being consciously aware of the presence of an object there. To do this, researchers used another standard test for humans which was similar to the previous study except moving objects were presented in the deficit visual field. Starting from the center of the deficit visual field, the object would either move up, down, or to the right. The monkeys performed identically to humans on the test, getting them right almost every time. This showed that the monkey's ability to detect movement is separate from their ability to consciously detect an object in their deficit visual field, and gave further evidence for the claim that damage to the striate cortex plays a large role in causing the disorder.

Several years later, another study compared and contrasted the data collected from monkeys and that of a specific human patient with blindsight, GY. GY's striate cortical region was damaged through trauma at the age of eight, though for the most part he retained full functionality, GY was not consciously aware of anything in his right visual field. In the monkeys, the striate cortex of the left hemisphere was surgically removed. By comparing the test results of both GY and the monkeys, the researchers concluded that similar patterns of responses to stimuli in the "blind" visual field can be found in both species.

Research

Lawrence Weiskrantz and colleagues showed in the early 1970s that if forced to guess about whether a stimulus is present in their blind field, some observers do better than chance. This ability to detect stimuli that the observer is not conscious of can extend to discrimination of the type of stimulus (for example, whether an 'X' or 'O' has been presented in the blind field).

Electrophysiological evidence from the late 1970s has shown that there is no direct retinal input from S-cones to the superior colliculus, implying that the perception of color information should be impaired. However, more recent evidence point to a pathway from S-cones to the superior colliculus, opposing previous research and supporting the idea that some chromatic processing mechanisms are intact in blindsight.

Patients shown images on their blind side of people expressing emotions correctly guessed the emotion most of the time. The movement of facial muscles used in smiling and frowning were measured and reacted in ways that matched the kind of emotion in the unseen image. Therefore, the emotions were recognized without involving conscious sight.

A 2011 study found that a young woman with a unilateral lesion of area V1 could scale her grasping movement as she reached out to pick up objects of different sizes placed in her blind field, even though she could not report the sizes of the objects. Similarly, another patient with unilateral lesion of area V1 could avoid obstacles placed in his blind field when he reached toward a target that was visible in his intact visual field. Even though he avoided the obstacles, he never reported seeing them.

A study reported in 2008 asked patient GY to misstate where in his visual field a distinctive stimulus was presented. If the stimulus was in the upper part of his visual field, he was to say it was in the lower part, and vice versa. He was able to misstate, as requested, in his left visual field (with normal conscious vision); but he tended to fail in the task—to state the location correctly—when the stimulus was in his blindsight (right) visual field. This failure rate worsened when the stimulus was clearer, indicating that failure was not simply due to unreliability of blindsight.

Case studies

"DB"

Researchers applied the same type of tests that were used to study blindsight in animals to a patient referred to as "DB". The normal techniques used to assess visual acuity in humans involved asking them to verbally describe some visually recognizable aspect of an object or objects. DB was given forced-choice tasks to complete instead. The results of DB's guesses showed that DB was able to determine shape and detect movement at some unconscious level, despite not being visually aware of this. DB himself chalked up the accuracy of his guesses to be merely coincidental.

The discovery of the condition known as blindsight raised questions about how different types of visual information, even unconscious information, may be affected and sometimes even unaffected by damage to different areas of the visual cortex. Previous studies had already demonstrated that even without conscious awareness of visual stimuli, humans could still determine certain visual features such as presence in the visual field, shape, orientation and movement. But, in a newer study evidence showed that if damage to the visual cortex occurs in areas above the primary visual cortex, the conscious awareness of visual stimuli itself is not damaged. Blindsight shows that even when the primary visual cortex is damaged or removed a person can still perform actions guided by unconscious visual information. Despite damage occurring in the area necessary for conscious awareness of visual information, other functions of the processing of these visual percepts are still available to the individual. The same also goes for damage to other areas of the visual cortex. If an area of the cortex that is responsible for a certain function is damaged, it will only result in the loss of that particular function or aspect, functions that other parts of the visual cortex are responsible for remain intact.

Alexander and Cowey

Alexander and Cowey investigated how contrasting stimuli brightness affects blindsight patients' ability to discern movement. Prior studies have already shown that blindsight patients are able to detect motion even though they claim they do not see any visual percepts in their blind fields. The study subjects were two patients who suffered from hemianopsia—blindness in more than half of their visual field. Both subjects had displayed the ability to accurately determine the presence of visual stimuli in their blind hemifields without acknowledging an actual visual percept previously.

To test the effect of brightness on the subject's ability to determine motion they used a white background with a series of colored dots. The contrast of the brightness of the dots compared to the white background was altered in each trial to determine if the participants performed better or worse when there was a larger discrepancy in brightness or not. The subjects focused on the display for two equal length time intervals and were asked whether they thought the dots were moving during the first or the second time interval.

When the contrast in brightness between the background and the dots was higher, both of the subjects could discern motion more accurately than they would have statistically through guesswork. However, one subject was not able to accurately determine whether or not blue dots were moving regardless of the brightness contrast, but he/she was able to do so with every other color dot. When the contrast was highest, subjects were able to tell whether or not the dots were moving with very high rates of accuracy. Even when the dots were white, but still of a different brightness from the background, subjects could still determine whether they were moving. But, regardless of the dots' color, subjects could not tell when they were in motion when the white background and the dots were of similar brightness.

Kentridge, Heywood, and Weiskrantz

Kentridge, Heywood, and Weiskrantz used the phenomenon of blindsight to investigate the connection between visual attention and visual awareness. They wanted to see if their subject—who exhibited blindsight in other studies—could react more quickly when their attention was cued without the ability to be visually aware of it. The researchers aimed to show that being conscious of a stimulus and paying attention to it was not the same thing.

To test the relationship between attention and awareness, they had the participant try to determine where a target was and whether it was oriented horizontally or vertically on a computer screen. The target line would appear at one of two different locations and would be oriented in one of two directions. Before the target would appear an arrow would become visible on the screen, sometimes pointing to the correct position of the target line and less frequently not. This arrow was the cue for the subject. The participant would press a key to indicate whether the line was horizontal or vertical, and could then also indicate to an observer whether or not he/she actually had a feeling that any object was there or not—even if they couldn't see anything. The participant was able to accurately determine the orientation of the line when the target was cued by an arrow before the appearance of the target, even though these visual stimuli did not equal awareness in the subject who had no vision in that area of his/her visual field. The study showed that even without the ability to be visually aware of a stimulus the participant could still focus his/her attention on this object.

"TN"

A potential weak point of case studies like the ones above is that the participants were not completely blind, and therefore it is not out of the question that their existing vision could have assisted them in some way. So a particularly noteworthy patient is a man known as “TN”, who suffered two strokes at age 52 that resulted in the destruction of the primary visual cortex (V1) in both hemispheres of the brain, and hence complete loss of (conscious) sight. In one famous case, researchers persuaded TN to walk down an obstacle-filled hallway, without his cane or any prior knowledge of the layout. He was able to navigate the full length of the hallway without hitting a single object, at one point even hugging the wall to get past a trashcan.

TN has taken part in a number of other experiments looking at blindsight. In one early study, he was shown images of expressive faces. While he could not guess the gender or shape accurately, he correctly guessed what emotion was shown at an above chance level. Brain imaging showed significant activity in the right amygdala, particularly in response to fearful faces, suggesting that the brain can unconsciously process expressions of emotion.

Similarly, another experiment investigated the brain’s sensitivity to looming stimuli, which often indicate an incoming collision. This sensitivity can involve heightened attention capture, but is also thought to operate on a subconscious level, and has been observed in monkeys and infants. In the experiment, both TN and a group of control participants were shown a series of moving red dots, some of which made looming motions. An fMRI scan of the control group showed that the movement of the dots produced normal activation in the middle temporal visual area (V5), known for its role in motion processing. In TN, activation was found in response to both general motion and to looming in particular; notably, however, this occurred primarily in areas of the brain not associated with motion processing in healthy individuals. Given that the specific V5 areas activated in the control participants were mostly lesioned in TN, this unusual activation seems to be a result of cortical plasticity.

Other cases

Other cases refer to SL, GY and GR.

Brain regions involved

Visual processing in the brain goes through a series of stages. Destruction of the primary visual cortex leads to blindness in the part of the visual field that corresponds to the damaged cortical representation. The area of blindness – known as a scotoma – is in the visual field opposite the damaged hemisphere and can vary from a small area up to the entire hemifield. Visual processing occurs in the brain in a hierarchical series of stages (with much crosstalk and feedback between areas). The route from the retina through V1 is not the only visual pathway into the cortex, though it is by far the largest; it is commonly thought that the residual performance of people exhibiting blindsight is due to preserved pathways into the extrastriate cortex that bypass V1. However both physiological evidence in monkeys and behavioral and imaging evidence in humans[ shows that activity in these extrastriate areas, and especially in V5, is apparently sufficient to support visual awareness in the absence of V1.

To put it in a more complex way, recent physiological findings suggest that visual processing takes place along several independent, parallel pathways. One system processes information about shape, one about color, and one about movement, location and spatial organization. This information moves through an area of the brain called the lateral geniculate nucleus, located in the thalamus, and on to be processed in the primary visual cortex, area V1 (also known as the striate cortex because of its striped appearance). People with damage to V1 report no conscious vision, no visual imagery, and no visual images in their dreams. However, some of these people still experience the blindsight phenomenon,[26] though this too is controversial, with some studies showing a limited amount of consciousness without V1 or projections relating to it.

The superior colliculus and prefrontal cortex also have a major role in awareness of a visual stimulus.

Lateral geniculate nucleus

Mosby's Dictionary of Medicine, Nursing & Health Professions defines the LGN as "one of two elevations of the lateral posterior thalamus receiving visual impulses from the retina via the optic nerves and tracts and relaying the impulses to the calcarine (visual) cortex".

What is seen in the left and right visual field is taken in by each eye and brought back to the optic disc via the nerve fibres of the retina. From the optic disc, visual information travels through the optic nerve and into the optic chiasm. Visual information then enters the optic tract and travels to four different areas of the brain including the superior colliculus, pretectum of the mid brain, the suprachiasmatic nucleus of the hypothalamus, and the lateral geniculate nucleus (LGN). Most axons from the LGN will then travel to the primary visual cortex.

Injury to the primary visual cortex, including lesions and other trauma, leads to the loss of visual experience. However, the residual vision that is left cannot be attributed to V1. According to Schmid et al., "thalamic lateral geniculate nucleus has a causal role in V1-independent processing of visual information". This information was found through experiments using fMRI during activation and inactivation of the LGN and the contribution the LGN has on visual experience in monkeys with a V1 lesion. These researchers concluded that the magnocellular system of the LGN is less affected by the removal of V1, which suggests that it is because of this system in the LGN that blindsight occurs. Furthermore, once the LGN was inactivated, virtually all of the extrastriate areas of the brain no longer showed a response on the fMRI. The information leads to a qualitative assessment that included "scotoma stimulation, with the LGN intact had fMRI activation of ~20% of that under normal conditions". This finding agrees with the information obtained from, and fMRI images of, patients with blindsight. The same study also supported the conclusion that the LGN plays a substantial role in blindsight. Specifically, while injury to V1 does create a loss of vision, the LGN is less affected and may result in the residual vision that remains, causing the "sight" in blindsight.

Functional magnetic resonance imaging has launched has also been employed to conduct brain scans in normal, healthy human volunteers to attempt to demonstrate that visual motion can bypass V1, through a connection from the LGN to the human middle temporal complex. Their findings concluded that there was an indeed a connection of visual motion information that went directly from the LGN to the V5/hMT+ bypassing V1 completely. Evidence also suggests that, following a traumatic injury to V1, there is still a direct pathway from the retina through the LGN to the extrastriate visual areas. The extrastriate visual areas include parts of the occipital lobe that surround V1. In non-human primates, these often include V2, V3, and V4.

In a study conducted in primates, after partial ablation of area V1, areas V2 and V3 were still excited by visual stimulus. Other evidence suggests that "the LGN projections that survive V1 removal are relatively sparse in density, but are nevertheless widespread and probably encompass all extrastriate visual areas," including V2, V4, V5 and the inferotemporal cortex region.

Controversy

The results of some experiments suggest that blindsighted people may be preserving some kind of conscious experience and thus they are not fully blind. The criteria for blindsight has repeatedly changed based on findings that challenge the original definition, which has led some scientists to cast doubt on the existence of blindsight.

Much Ado About Nothing

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Much_Ado_A...