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Many thousands of rats, mice, kittens, eels, guinea-pigs, opossums, rabbits, sheep, cattle, pigs, frogs and toads are used in universities every year. Thousands of Queensland toads are imported for routine dissection purposes. These are killed by "pithing", a process involving pushing a probe into the brain and moving it about to ensure the entire brain is destroyed. "The toad doesn't feel anything" assures Dr John Miller, physiologist of Victoria University animal ethics committee... (more of those ethics!)
"Thus use your frog:
... Put your hook through his mouth and out his gills, and then with a fine needle and silk sew the upper part of his leg, with only one stitch, to the arming wire of your hook; or tie the frog's leg, above the upper joint, to the armed-wire; and in so-doing
Use him as though you loved him."
- Izaac Walton
Swammerdam, a generous user of frogs as subjects for the study of nerve and muscle action wrote before abandoning the frog for other fields:
"As to myself, I candidly confess, that I have not brought every subject which I have advanced, to the greatest possible perfection: For, in order to attain this, I should have spent my whole life discovering one thing, and this of course is not agreeable to me: For I am thoroughly persuaded that, if I came to the utmost extremity, I should at last discover nothing but my own ignorance.
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Rats are also "pithed".
From Animal Experiments in Pharmacological Analysis, by FR Domer 1971 we read:
"Male rats weighing between 150 and 300gm were anesthetized with sodium amobarbital and atropine sulfate. The trachea, femoral vein and carotid artery were all cannulated. The vagi were then cut and the jugular vein and the carotid arteries were tied. With the animal lying on its back and its hind legs pinned to the operating board the animal was ready to be pithed. The pithing rod was made from a coat hanger and was 2.2 mm in diameter and about 25cm long, with one end bluntly pointed. By holding the animal's head taut and in line with the vertebrae with the thumb in the angle of the mandible and the forefinger around the top of the skull, the point of the pithing rod was inserted obliquely into and through the eye socket at an angle of about 45 degrees to the long axis of the rat. After the skull had been entered the rat was realigned with the vertebral column and the pithing rod was passed through the cranium and down the whole length of the spinal cord . The rod was left in place on the assumption that it would afford mechanical compression of the blood vessels torn in the process of pithing. The blood pressure was then recorded and artificial respiration was about 50 to 60 cycles per minute."
This pithing technique is used to advantage in causing a complete simulation of the sympathic outflow from the spinal cord of the rat...
says Gillespie and Muir (1976)...
(Continued next page)
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