måndag 1 april 2013

According to science fish are conscious and do feel pain

Quote from article claiming that fish don't feel pain:

" However, the new research, which reviewed a series of studies conducted over the years, discovered that only an extremely small number of “C fibres” - a type of nociceptor responsible for pain - can be found in trout and other fish."

Both A-delta and C fibres are noiceptors responsible for pain:
In higher vertebrates nociceptive nerves are either A–delta or C fibres with C fibres being the predominating fibre type. However, in the rainbow trout A–delta fibres were most common, and this offers insights into the evolution of nociceptive systems. Administration of noxious substances to the lips of the trout affected both the physiology and the behaviour of the animal and resulted in a significant increase in opercular beat rate and the time taken to resume feeding, as well as anomalous behaviours. This study provides significant evidence of nociception in teleost fishes and furthermore demonstrates that behaviour and physiology are affected over a prolonged period of time, suggesting discomfort. "
Quote: http://rspb.royalsocietypublishing.org/content/270/1520/1115

A-delta-fibres are associated with the first sensation of pain: Link [  Do fishes have nociceptors? Evidence for the evolution of a vertebrate sensory system L. U. Sneddon1,*, V. A. Braithwaite2 and M. J. Gentle1; Proceedings of the Royal Society ]

Another quote: "Professor James Rose from the University of Wyoming in the US, who led the study, also found that the fish brain does not contain the highly developed neocortex needed to feel pain, so do not experience it in any meaningful way like humans.
He concluded that fish are able to experience unconscious, basic instinctive responses, but that these did not lead to conscious feelings or pain."

Many other researchers now believe that animal consciousness does not require a neocortex, but can arise from homologous subcortical brain networks. See: The Cambridge Declaration on Consciousness 7 July 2012. Written by Philip Low and edited by Jaak Panksepp, Diana Reiss, David Edelman, Bruno Van Swinderen, Philip Low and Christof Koch. University of Cambridge.

Anyone who made it through Biology 101 knows that fish have nerves and brains that sense pain, just as all animals do. Dr. Donald Broom, a scientific advisor to the British government, explains, "The scientific literature is quite clear. Anatomically, physiologically and biologically, the pain system in fish is virtually the same as in birds and mammals."

Neurobiologists have long recognized that fish have nervous systems that comprehend and respond to pain. Scientists tell us that fish brains and nervous systems closely resemble our own. For example, fish (like "higher vertebrates") have neurotransmitters such as endorphins that relieve suffering; the only reason for their nervous systems to produce these painkillers is to relieve pain. Researchers have created a detailed map of pain receptors in fish's mouths and all over their bodies. A team at the University of Guelph in Canada recently surveyed the scientific literature on fish pain and intelligence. They concluded that fish feel pain and that "the welfare of fish requires consideration."

A two-year study by scientists at Edinburgh University and the Roslin Institute in the U.K. proved what many marine biologists have been saying for years: Fish feel pain, just as all animals do. Anglers may not like to think about it, but fish suffer when they are impaled in the mouth and pulled into an environment in which they cannot breathe. Said Dr. Lynne Sneddon, who headed the study,"Really, it's kind of a moral question. Is your angling more important than the pain to the fish?"

A study by scientists at Queen's University Belfast proved that fish learn to avoid pain, just like other animals. Rebecca Dunlop, one of the researchers, said, "This paper shows that pain avoidance in fish doesn't seem to be a reflex response, rather one that is learned, remembered and is changed according to different circumstances. Therefore, if fish can perceive pain, then angling cannot continue to be considered a noncruel sport."

Fish can also suffer from fear and anticipation of physical pain. Researchers from universities across America have published research showing that some fish use sound to communicate distress when nets are dipped into their tanks or they are otherwise threatened. In a separate study, researcher William Tavolga found that fish grunted when they received an electric shock. In addition, the fish began to grunt as soon as they saw the electrode in anticipation of the torment that Tavolga was inflicting on them.

According to Dr. Michael Fox, D.V.M., Ph.D., "Even though fish don't scream [audibly to humans] when they are in pain and anguish, their behavior should be evidence enough of their suffering when they are hooked or netted. They struggle, endeavoring to escape and, by so doing, demonstrate they have a will to survive."
[Quote: Cat Jones]
The bottom-line is that fish are conscious.
A sentient being is a being who is subjectively aware; a being who has interests; that is, a being who prefers, desires, or wants. Those interests do not have to be anything like human interests. If a being has some kind of mind that can experience frustration or satisfaction of whatever interests that being has, then the being is sentient.

We engage in speciesist thinking when we claim that a being must have a humanlike mind to count morally. That is, it is speciesist to claim that a being must have a reflective sense of self awareness, or conceptual thought, or the general ability to experience life in the way that humans do in order to have the moral right not to be used as a resource. As long as there is someone there who is subjectively aware and who, in that being’s own way, cares about what happens to him or to her, that is all that is necessary to have the moral right not to be used as a resource.

Quote: http://www.abolitionistapproach.com/sentience/#.UVmlZFev_gM

One of the main arguments that I make is that although almost everyone accepts that it is morally wrong to inflict “unnecessary” suffering and death on animals, 99% of the suffering and death that we inflict on animals can be justified only by our pleasure, amusement, or convenience. For example, the best justification that we have for killing the billions of nonhumans that we eat every year is that we enjoy the taste of animal flesh and animal products. This is not an acceptable justification if we take seriously, as we purport to, that it is wrong to inflict unnecessary suffering or death on animals, and it illustrates the confused thinking that I characterize as our “moral schizophrenia” when it comes to nonhumans.

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