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Location: Virtual Showground
Joined: Aug 2006
Posts: 9,518
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Originally Posted by
Hewey
A neonatal puppy, after just 9 weeks gestation has an incomplete nervous system yet to develop from the spine through to the tail which is not yet required to move and so evolution has not made a priority. Not really comparable.
You are incorrect, and it is comparable.
The evidence is available and has been for years.
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INCORRECT MYTHS ABOUT PAIN.
Several myths about pain have been propagated for years and form the basis on which cosmetic tail docking
has been justified and allowed to be perpetuated.
MYTH 1 - Animals don't feel pain like humans. This is illogical. Anatomically and physiologically mammals
(and possibly all vertebrates) have the same neural transmitters, receptors, pathways and higher brain centres.
Whilst it is true that animals may show different signs of pain, we cannot deny that they feel pain in the same
way humans do (Fleeman 1995). Because of the physiological similarity between mammals, it is valid to use
animals, including dogs, as models for human medical research. The converse applies in that man can be used
as a model for advancing veterinary knowledge. Similarity between the human and canine nervous systems
means that we can assume that anything causing pain in man will cause a painful sensation of similar intensity
in the dog.
The pain threshold has been determined to be approximately equal in humans and animals
(Fleeman 1995).
MYTH 2 - Lack of myelination is an index of immaturity in the neonatal nervous system and therefore
neonates are not capable of pain perception. We know this is no longer correct, in fact the contrary occurs.
Anatomical studies have shown that the density of cutaneous nociceptive nerve endings in the late foetus and
newborn animal may equal or exceed that of adult skin (Anand and Cart 1989). Nociceptive impulses are
conducted via unmyelinated and thinly myelinated fibres. The slower conduction velocity in neonatal nerves
resulting from incomplete myelination is offset by the shorter interneuronal and neuromuscular distances that
the impulse has to travel.
It has been shown, using quantitative neuroanatomical methods, that nerve tracts
associated with nociception in the spinal cord and brain stem are completely myelinated up to the thalamus
during gestation (Anand and Cart 1989). Further development of the pain pathways occurs during puppyhood
when there is a high degree of 'brain plasticity.'The development of descending inhibitory pain pathways in the
dorsal horn of the spinal cord and the sensory brain stem nuclei also occurs during this period, therefore painful
and other experiences during this period may determine the final architecture of the adult pain system.
THE PAIN OF TAIL DOCKING.
Tail docking involves the removal of all or part of the tail using cutting or crushing instruments. Muscles, tendons,
4 to 7 pairs of nerves and sometimes bone or cartilage are severed.
The initial pain from the direct injury to the
nervous system would be intense and at a level that would not be permitted to be inflicted on humans. The
subsequent tissue injury and inflammation, especially if the tail is left to heal as an open wound will produce
the algogenic substances, the 'sensitising soup' and the 'dorsal horn wind up' required for peripheral and central
sensitisation and the development of ongoing pathological pain.
Puppies are usually subjected to this pain and
trauma at 2 to 5 days of age when the level of pain would he much greater than an adult would experience
because the afferent stimuli reaching the dorsal horn from a greater density of sensitised cutaneous nociceptors
will exceed that of the adult and the strength and frequency of painful stimuli reaching the brain will he greater
because inhibitory pain pathways will not be developed.
*
The whimpering and the 'escape response' (continual movements) exhibited by most puppies
following tail docking, are evidence that they are feeling substantial pain. Animals tend to be
more stoic than humans due to an inherent preservation instinct.
*
Because some puppies do not show signs of intense suffering, it does not mean that the pain
inflicted on them has not registered in their central nervous system.
http://www.anti-dockingalliance.co.uk/page_4.htm
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