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by Professor Pietro Croce, MD

First published in Italy in 1981
Republished in English (and updated and expanded) in 1991
Copyright © 1991 by Hans Ruesch Foundation

Published by
POB 152
via Motta 51
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Translated from the Italian by Henry Turtle in collaboration with the Author.

Prof. Pietro Croce, MD is a luminary of medical science. Born in Dalmatia in 1920, he graduated at the famed University of Pisa, Italy. His curriculum includes: Fulbright Scholarship, Research Department of the National Jewish Hospital of Colorado University in Denver, Research Department of Toledo, Ohio. Research Departmente of Barcelona, Spain. From 1952 and 1982, head of the laboratory of microbiological-pathological anatomy and chemo-clinical analyses at the research Hospital L. Sacco of Milan, Italy. A member of the College of American Pathologists, he is also a prolific author of medical books, scientific papers and press articles. He now lives in Vicenza Italy, with his Swiss wife and their teenage son.




On the Road to Damascus

I used to experiment on animals for many years. I had been obeying a stale positivistic logic which had been imposed on me during my university studies and which for a long time conditioned me in the following years.

"Scientific positivism, the only possible logic in medical and biological research."

But to assert that the human mind can have "only one possible logic" means admitting that it is unable to look in more than one direction.

With my head filled with notions handed down by the professors, from books, practice in hospitals in Italy and abroad, I tried to put my thoughts in order and forced myself to arrange my convictions in logical sequence. But it was like trying to assemble a jig-saw puzzle which had left the factory in defective condition; the pieces did not fit together, producing distorted images, separated by spaces which could not be filled and forming a mosaic which at the least jolt fell apart, scattering in chaotic disorder.

I said to myself: there must be something wrong with medical thinking and practice. The factor must be both fundamental and elementary, capable of undermining its entire basis and vitiating everything built upon it: a methodological error.

Vivisectionist thinking arises from empirical science which reached its peak in the last century and which postulates the choice and the construction of "experimental models" with which to reproduce ad libitum (freely) those phenomena to be researched.

As an example, two condensors charged positively and negatively with electricity placed near together produce a spark. This is the experimental model of a natural phenomenon which is lightning. But for the study of man, what is the appropriate model for his functions and his malfunctions of his illnesses?

The solution seems obvious, but just for this reason it contains that deception which threatens all those things that, at first sight, seem to be "even too obvious". The proposition is made: "Let us take the animal as the experimental model for the human being." But here at once comes the first objection: "Which animal?" There are millions of species of animal on the earth. So, which should we use? The mouse? The dog? And why not the rhinoceros or the warthog?

In the physical and mechanical sciences the researcher projects and constructs his experimental model with characteristics appropriate to the aim he sets for himself each time.

In contrast, the researcher in biological sciences, assuming "the animal" to be the model, is obliged to accept something offered to him "prefabricated" by Nature. And it would indeed be a strange and improbable coincidence if such characteristics were right for the ends in view.

Even the choice between different species of animal is illusory: actually one is not even speaking of there being a choice at all, but of a kind of fishing blindly among different possibilities in a haphazard way or, worse, according to opportunistic criteria in deciding which animal is more or less convenient: the mouse, the rabbit, the guinea pig are "convenient" because they are easy to keep; cats and dogs because they are easily and cheaply obtainable: everything except the one element which ought to be the deciding factor: an animal having morphological, physiological and biochemical characteristics applicable to man. However, such an animal can only be man himself, or a chimera.

An experimental model of the human being does not exist. Every species, all the varieties of animals and even individuals of the same species are different from each other. No experimentation carried out on one species can be extrapolated to any other, including man. To suppose that such extrapolation could be legitimate is the main reason for the failure and sometimes for the catastrophes which are inflicted upon us by modern medicine, especially in the area of drugs. Too little is spoken or written about certain facts, partly in deference to a science which purports to be the "saviour of mankind", but more usually to avoid provoking the huge economic and political interests which prop up this benefactor. For example, in August 1978 only Japanese newspapers reported the appearance in Tokyo of 30,000 people paralysed and blinded by Clioquinol. The trial and sentencing of the firm which produced the drug was necessary for us to be able to know about the matter indirectly.

Another example: some publications like "Il Bollettino d'Informazione sui farmaci" (Drug Information Bulletin) of the Ministry of Health are not widely read. The issue of no. 8 of August 1983 tells us that:

"From 1972 to June 1983 the registration of 22,621 medicinal preparations has been revoked" (i.e. the sale prohibited). Clearly, all those preparations had passed with flying colours the animal experiments imposed by law.

But how many years must pass before it is realised that a medicine is dangerous and how many have fallen victim to it in the meantime?

This question is answered by Professor Hoff, (Congress of Clinical Medicine, Wiesbaden, 1976) "...6% of fatal illnesses and 25% of all illnesses are due to medicines".

Prof. Dr. Remmer of Tuebingen, at a meeting of German insurance companies, said " the Federal Republic of Germany about 30,000 deaths a year are due to medicines".

Our demand for the abolition of animal experiments is not based on a love of animals but a concern for the health of our fellow human beings.

Anti-vivisectionist thinking is much more scientific than the boasting of the vivisectors who do not realise that they live and function in a medieval climate of thought; besides, they are too lazy or too greedy to break loose from a comfortable conformity and apply themselves to scientifically correct methods, i.e. those methods which are wrongly called "alternative" and are today largely obsolete, having been overwhelmed by a misleading methodology.

There are many "alternative" methods; about 450 have been counted. However, their number is theoretically unlimited as every research endeavour presupposes devising a method specific to that research, able to guarantee a credible result, in harmony with scientific logic, repeatable ad libitum and capable of satisfying the "criterion of falsification"* - all qualities missing from the vivisectionist method.

Scientific progress is achieved only by small steps. We would prefer them to be "tiny" steps, but sure ones. The vivisectors like to present animal experimentation as a short cut to biological science without, however, having noticed that such a short cut leads them in the wrong direction. The claim that medicine must progress by "trial and error" is unacceptable. In medicine, error means the sacrifice of one person or thousands of people. We say deliberately "one or thousands" because for us "one" is of as much value as "thousands". The vivisector says: "But we work for the benefit of the majority". NO. You have no right to sacrifice anybody, not even one person, for the hypothetical and entirely uncertain benefit of an indefinite number of "others" at some unspecified time in the future.

A few minutes ago (it is 5.25 p.m. on 16 November 1984) the radio announced that Baby Fae** had died.

* The "criterion of falsification" expounded by Karl Popper (the Austrian philosopher) asserts that a proposition is not scientific if it cannot also be proven wrong. For example, the proposition "In a thousand years the sun will be extinguished" is not scientific because nobody is in a position to demonstrate that the event announced will not happen.
** Baby Fae is the nickname given to a baby girl born in California on 14 October 1984, with a heart malformation which meant that she could not survive for long. On the 26th October 1984 at the University Medical Centre of Loma Linda, Dr. Leonard Bailey transplanted a baboon's heart into her. A procession of people marched past the hospital in protest. The little victim died 21 days after the operation due to rejection of the new heart.
Baby Fae was the guinea-pig in an experiment of vivisection. The primary object (presumably) of the experiment was to establish whether rejection would take place even when the immune system is incomplete. It is an interesting scientific fact that rejection occurred, even though it was easily predictable. But, apart from that scientific fact, human and medical ethics must be taken into account. No scientific advance can be justified by torture.
But that is not all. A footnote makes this dreadful story quite incredible even at an elementary technical level (I deliberately avoid the term "scientific level"): Prof. Bailey himself tells us that rejection did not take place due to the incompatibility of the baboon's heart with the baby's tissues, but because - and this is absolutely inconceivable - his team did not bother to do what is done every day in any "AVIS" (Associazione Volontaria Italiana del Sangue - Italian Blood Transfusion Service) in Italy and around the world. His team did not check the blood group of the donor (the baboon) and the recipient (the baby girl). It turned out later that Baby Fae was of Blood Group "O" while the baboon was of Blood Group "AB".
Prof. Bailey commented: "The mixing of the blood groups was fatal. We were more afraid of the difference between the species than about the blood. We made a mistake". (from "La Repubblica", May 13, 1987). One can only hope that Prof. Bailey will learn from his blunder. And in fact Prof. Bailey "promised" to try again at the first opportunity. All the best, Prof. Leonard Bailey.

THEY HAD NO RIGHT TO DO IT. As a scientist, I recognise the great scientific interest of the experiment, but as a human being I maintain that the baby girl has been used as a guinea-pig and the offender should be punished by law. Otherwise one shares in that perverse way of thinking that "the ends justify the means", a catastrophic maxim that has cast a blight upon mankind for thousands of years.

Let us return to the "trial and error" concept. I prefer to call "scientific" those methods that others call "alternative". They are scientific because they are the most reliable, permitting a minimum of error, that is, of human suffering and death. There are three basic scientific methods - epidemiological research, mathematical models and cell and tissue culture in vitro. These methods do not allow us to promise sensationally rapid progress but, they are short, safe steps on a straight path.

It is often asked: "Why, then, are they so little used?" One reason is that universities, in their arrogant and musty academicism, continue to instruct the new generations of students by means of animal experiments. They are unable or willing to free themselves from a way of thinking and acting in which they plod blindly round in a dead-end street. It is easier to keep to old habits than to innovate, and for this reason a certain cultural climate still prevails. But even the mightiest empires collapse, and the greater their power, the noisier the crash when it comes.

Some vivisectionists, perhaps those gifted with a more critical cast of mind, begin to have doubts and look for a way to reconcile them. They admit that animal experimentation is uncertain, but it gives an indication that one is on the right track, which makes it worthwhile continuing in the same direction. "Indication" means "incomplete, guiding information". Incomplete information can indeed be useful under one condition - that it is correct.

We recall the story of the traveller who stopped a passer-by to ask: "Excuse me, where is the Church of St. Giobbe". The one asked makes a vague gesture with his hand in the eastward direction. This is an "indication", that is, a bit of information which, however incomplete, may help if the direction indicated is right. But if the passer-by, instead of giving an indication towards the EAST (where the church really is) indicates the WEST, or the SOUTH, or the NORTH, then his indication is not only incomplete, but also wrong and misleading.

The same is true of the vivisectionist method of research. If it gives incomplete, but correct indications, the method might be of some use. On the contrary, it is not only useless, but even misleading, because it provides only accidentally indications which coincide with the right direction, without the researcher having any way of foreseeing whether a fortunate coincidence can be verified or not.

What do the terms "by chance" or "by coincidence" mean? We have no difficulty in admitting that, for example, a substance poisonous for the dog can be so also for man; but that may be a pure coincidence obeying the law of probability, and, in accepting it, we commit an error which could claim victims before we become aware of it. There are, in fact, plenty of victims of modern medicine, so many, that learned papers are written about iatrogenic illnesses, that is, illnesses caused by doctors who seem to have forgotten the basic Hippocratic precept: Primum non nocere (First, don't cause harm).

The notion of vivisectionist experimentation on man is not a macabre fantasy. It is reckoned today to occur on a large scale. The vivisectors themselves are clearly beginning to realise that to experiment on one species of animal in order to extrapolate the results to another species (inter species experimentation) is a methodological error. They are therefore turning to intra speciem experimentation which means experimenting on the dog to learn things about the dog, on the cat to learn things about the cat... and on human beings to learn things about humans. But this sophisticated variation of vivisection, despite its allure, does not guarantee any more reliable results than those obtained by experimentation inter species (between species).

"No animal species can be an experimental model for any other species"; only superficial judgement can be content with morphological similarities like saying "the dog too, like man, has a head, two eyes... a liver, a heart, etc". Just as crude and misleading is it to have recourse to certain behavioural analogies as: "if I crush the foot of a dog, it howls, if I crush the foot of a man, he cries out, if I take the new-born infant away from a female monkey, she mourns, if I take the new-born baby away from a human mother, she mourns."*

* This truth should be reconsidered from its very roots: see the chapter about human mothers selling their children for vivisection.

These analogies exist and it would be foolish to deny them, but why do they exist? Having a common root they are attributes of that unfathomable and indivisible entity we call LIFE, an entity pervading the universe and possessing the quality of immanence, manifesting itself in every being, be it a plant, a worm or a man*.

However, turning to the material components of the tissues of countless animal species one needs to pause for a moment to consider the following: can two species of animal be considered analogous when it is known that the tissues of each species are made up of thousands of proteins (about ten thousand) of which not one belonging to one of two species is identical to a corresponding protein of the other species, and whose DNA (dioxyribonucleic acid) molecules which transmit hereditary characteristics, are all unlike each other in different species?**

DNA molecules differ from each other in different animal species, by the length of the chain of their double helix, by the number and arrangement of the nucleotids of which they are made up. The combinations which one can hypothesize from mathematical calculation are billions of billions, that is, as many combinations as are possible bearing in mind that there are about three billion nucleotids in human DNA.

A fundamental rule, to be strictly observed in each scientific experiment, is that each experiment must be capable of being repeated. An experiment is repeatable when it is carried out anywhere, at any time and by any researcher, and always produces an identical result. If that does not happen it means that there is something wrong. Either the hypothesis is wrong*** or it is not demonstrable or the method used to demonstrate it is flawed. Now, the question is this: does the experimentation on animals (including the human being) have the intrinsic characteristic of being repeatable anywhere, at any time and by any researcher?

* That certain types of behaviour should have a common root seems clear when we pause to consider, without scientific bias, any living being: the search for food, flight from danger, the reproductive urge and other kinds of behaviour which we might for the sake of convenience term "instinct". These fundamental attributes of the phenomenon LIFE.
** Diversity between proteins and between other components (mainly polysaccharides) of different species (animals and plants) is basic to all phenomena in immunology, from allergies to organ rejection.
*** A false proposition is of this type: "Man can fly by waving his arms". This proposition, however, contains within itself Popper's criterion of falsification, because anyone can demonstrate its falseness. On the other hand, a proposition of which nobody could ever demonstrate the falsity is the following: "In a thousand years the sun will be extinguished".

The reply comes from research carried out at the University of Bremen, in a paper entitled "Die Problematik der Wirkungsschwelle in Pharmakologie und Toxikologie" ("Problems of activity threshold in pharmacology and toxicology"):*

  1. In ionizing radiation young animals react differently from older ones.
  2. Tranquillisers - there are big differences in their effects between young animals and old animals.
  3. LD-50%: in the experiments carried out in the evening almost all the rats died; in those carried out in the morning all of them survived. In the tests carried out in winter, survival rates were doubled in contrast to those carried out in summer. In tests carried out with poisonous substances on mice crowded together in cages, nearly all of them died, while in those carried out on mice living in normal conditions, all the mice survived.

The authors of this research concluded that "if such trifling environmental conditions bring about such widely differing and unforeseeable results, this means that animal experimentation cannot be relied upon in assessing a chemical substance and it is all the more absurd to extrapolate to problems of human health results which are intrinsically wrong."

Finally, the following should be noted. The above observations are made, not by anti-vivisectionists, but by vivisectors, who have had the merit of defining the limits of a methodology in which, hitherto, they have certainly believed.

* The data indicated with an asterisk on this and on part of the next page were supplied by the medical doctor and surgeon Dr. Werner Hartinger of Waldshut-Tiengen.

Alternative Methods: Alternative to What?

Are there alternatives to vivisection? Of course not.

Then what is the point of this book? And why is there widespread disgust at vivisectors? Why do researchers in increasing numbers refuse to experiment on animals? And what about the lawsuits brought against vivisectors and the court sentences handed down to them?

This subject, too, like all expressions of thought, requires semantic definition.

There are no alternatives to vivisection, because any method intended to replace it should have the same qualities; but it is hard to find anything in biomedical research that is, and always was, more deceptive and misleading than vivisection. So the methods we propose for medical research should be called "scientific methods", rather than "alternative methods".

The vivisectors ask us: "What would you offer us instead of vivisection in scientific research?" Instead of vivisection: nothing. Vivisection is a suppurating sore making science ill, bringing it into disrepute, even with the general public. The vivisectors should not ask: "What are you offering to science?" but more honestly: "What are you offering to us?"

They would, of course, have to give up an easy way of acquiring academic titles, having papers published, advancing their careers and making money. They would also have to relinquish the chance of ingratiating themselves with the powers-that-be by supporting one thesis one day or, as smoothly, its opposite the next, by means of "irrefutable" experiments.

There are many ways of producing "irrefutable" facts in support of any argument, using different kinds of animals: one just has to choose the right one. For example:

Do we want to show that Amanita phalloides is an excellent edible toadstool? Then we have only to feed it to the rabbit.

Do we wish to ruin the trade of citrus fruit growers? Let us poison the cat with lemon juice which we add as a flavouring to our food.

Do we want to make someone fall asleep? Then let us give the person morphine. Do we want to send the cat into a frenzy of excitement? Let us give it morphine. But morphine has the same effect on the rat as on a human being: it sends it to sleep.

If we wish to demonstrate that prussic acid (whose fumes can kill a man) is an excellent aperitif, let us give it to toads, sheep and hedgehogs.

Do we want to discourage people from eating parsley? Let us give it to the parrot which will probably be found lying stone-dead under its perch the next morning.

Should we wish to rule out penicillin as a therapeutic drug, we have only to give it to the guinea-pig which will be dead in a couple of days.*

The insipid pumpkin makes the horse frisky.

The amount of opium that can be eaten without discomfort by the hedgehog would keep the most hardened addict happy for a fortnight.

If we wish to convince the consumers of tinned food that botulin poison is harmless let us give it to the cat and it will lick its lips. Let us give it instead to the cat's traditional prey, the mouse, and it will die as if struck by lightning.

Illicit producers of alcoholic drinks have caused blindness in thousands of people by adding methyl alcohol to their products. But methyl alcohol does not damage the eyes of the most commonly used laboratory animals.

* It seems that the lethal action of penicillin on the guinea-pig is indirect, that is, due to a change in the intestinal floral bacteria. However, this does not alter the value of the observation that the same thing does not occur in other animals, including man.

It is well known to writers of crime fiction that arsenic is poisonous, whereas the sheep demonstrate that it is not because it can consume it in large quantities.

Antimony, a metal, when added to the feed of pigs fattens them, but "kills monks", that is, people.*

If we need to show that Vitamin C is useless we withhold it from the diet of the most readily available animals: the dog, the rat, the mouse, the hamster... they will continue to thrive because their bodies produce Vitamin C of their own accord. But let us not eliminate it from the diet of guinea-pigs, primates, or humans or they will die of scurvy.

A hundred milligrams of scopolamine is harmless to dogs and cats.** But five milligrams would kill a man.

Strychnine, like arsenic a favourite weapon of murderers in crime novels, is harmless to guinea-pigs, chickens and monkeys in amounts capable of causing convulsions in an entire human family. Hemlock, well-known through the death of Socrates and deceptively similar in appearance to parsley, is eaten with relish by goats, sheep, horses and mice.

Amyl nitrate raises the internal pressure in the eye of dogs to dangerous levels, but reduces the pressure in the human eye.

Chloroform, used successfully for decades in human surgery, is poisonous for dogs.

Insulin causes malformations in chickens, rabbits and mice, but nothing similar has been found in human beings.

Cortisone causes malformations in mice and rabbits, but not in man so far as is known.

Digitalis was considered dangerous because, tried out on dogs, it raised their blood pressure. Thus the use of this drug, so useful in treating some cardiopathies, was delayed at least a decade.***

* The name antimony (symbol Sb from the Latin "stibium") derives from the French term "antimoine", that is, "anti-monk". In the Middle Ages a Benedictine monk, Basilius Valentin (born in Erfurt, Thuringia), alchemist in a French monastery, noticed that antimony added to the mash for pigs, fattened them. So, he added it to the soup of his brother monks, and he caused a slaughter.
** In judging the toxicity of a drug one must always refer to the relationship between the dose of the drug and the body mass (weight) of the animal. Thus, for example, as the cat (average weight 4 kilos) will tolerate without evident ill effect 100 milligrams of "scopolamine", given that it weighs about 18 times less than a human being (average weight 70 kilos), that is as if it could tolerate about 1800 milligrams, that is a dose 360 times greater than that tolerated by a human being.
*** Dr. James Burnett: "We used to believe, as a result of experiments on animals, that digitalis raised blood pressure. Now we know that this is sheer nonsense. Digitalis is a very useful drug in certain cases in which the blood pressure is very high." (Medical World, July 3, 1942, p. 388).

Metamizol is used as an anaesthetic for man but drives cats into a frenzy and causes excessive salivation, similar to that found in an animal supposed to be suffering from rabies.

Cicloserine, useful in the treatment of tuberculosis in humans is inactive against experimental tuberculosis of guinea-pigs and mice.

Phenylbutazone (an anti-inflammation drug) can be given to dogs (and other animals) in strong, frequent doses, as it is rapidly rendered inactive. But if given to a human being, it would soon cause cumulative poisoning, as in man the drug becomes active 100-150 times more slowly.

Chloramphenicol damages, sometimes badly, the haematopoietic (blood-producing) bone marrow in man, but in no other animal.

Orotic acid has a beneficial effect on the human liver, but causes fatty degeneration in the liver of the rat.

Chlorpromazine damages the liver in man, but not that of laboratory animals.

Ergotinine is tolerated by the rabbit but is poisonous to dogs and human beings.

Atropine is not poisonous to rats, pigeons, goats* and many strains of rabbit (those possessing the enzyme atropinesterase), but it is toxic for other strains. It is especially poisonous for man, for whom it can be used only in extremely small doses (0.25 - 0.5 milligrams). Moreover, it has a slight effect on horses, donkeys and - on monkeys, nowadays popular laboratory animals because they "so much resemble the human being"!

Methyl fluoracetate is poisonous for mammals. However, the mouse can tolerate doses 40 times stronger than those which kill a dog. And man? Does the human being react like the mouse or the dog?

Compounds based on organic phosphate (like the disinfectants Mipaphox, Trichlorphon, Dipterex) seriously damage the nervous systems of man and other animals. But the mouse can tolerate without apparent harm enormous doses (up to 1500 mg/Kg of its body weight) of the commonest of these compounds, ToCP (Tri-orto-Cresyl-Phosphate).

To sum up, one has only to know how to choose the proper animal species to obtain the desired results - black or white, beautiful or ugly, high or low. This is a kind of science which one can knead like dough. The trouble comes in believing that with dough one can produce health for human beings.

It should not be difficult even for the layperson to draw from the preceding examples a fundamental conclusion. If animals differ so much from man in their reactions, how can one test on them drugs intended for man?

* Goats can graze without damage on the plant "Atropa belladonna", a common plant of the Solanaceae family.
The leaves and roots contain hyoscyamine which under certain conditions become the isomere atropine.

The truth is that all living organisms, animals and plants, are at the same time marvellously like and marvellously unlike each other. There is no contradiction here provided that one considers the matter from different points of view.

All living organisms are marvellously alike, because all of them, from the bacterium to man, have certain chemical compounds in common. It is obvious that this should be so as everything that lives on the earth is derived from the earth and cannot have more than the 92 elements that are to be found in the world.

All living organisms are marvellously different from each other. The diversity is not only between plants and animals, or between different species, but individuals of the same species or race are different from one another. Differences between individuals of the same species have arisen due to the existence of many "enzymatic variations"* corresponding to differences in behaviour caused by certain stimuli.

Some examples are:

About 10% of individuals of Caucasian type, reaching the age of 20-25 start to be unable to tolerate milk sugar, (lactose). They are not ill, they are just a bit different from the others. About 65% of people find Phenil-Thiourea bitter. The rest find it insipid. Why? Because there is some difference between them, but we do not know whether it lies in the taste buds or elsewhere in the chain that carries the stimulus from the peripheral receptor organ to the brain to be consciously evaluated.

Based on blood groups, the population is divided into groups A, B, AB, O. Why should there be this diversity? The Jehovah's Witnesses would say that it is to prevent blood transfusions.

Most people do not eliminate beta-amino-isobutyric acid in their urine, but about 8% of them do. Why?

* The enzymes are catalysts of organic reactions. They act in extremely small amounts and while not taking part in the reactions bring about reactions which would otherwise only occur very slowly or by the use of large amounts of energy.
For example, a common reaction in all animal cells is the oxidation of glucose. To oxidise the glucose outside the organism a raised temperature or the use of energising oxidants is required, whereas in the cell, thanks to the enzymes, the oxidisation of glucose takes place at a low temperature (in mammals at about 37ºC, in cold-blooded animals, even at 4-5ºC).
The enzymes are proteins and become inactive at a temperature of about 60ºC.
All organic reactions are controlled, guided, accelerated or retarded and coordinated by enzymes.

The red blood corpuscles contain acid phosphatase, an enzyme that is to be found almost everywhere in the organism. But acid phosphatase is not the same in all individuals who, due to this diversity, are divided into five groups: A, BA, B, CA and CB.

The red blood corpuscles contain two kinds of carbonic anhydrase, designated by the symbols CA-Ia and CA-II. But some people have another type, CA-Ib, and others have still another type, CA-Ic.

Blood contains at least 17 kinds of transferrin (the protein which carries iron) but the proportions vary in different individuals.

Albumin comprises 52% of the serum proteins. But some individuals have two kinds (distinguishable by their different electro-phoretic mobility): albumin A and albumin A2.

The haptoglobins are proteins which bind haemoglobin released from haemolysis, thus avoiding elimination in urine. There are six normal haptoglobins present in different proportions in different individuals. However, "abnormal" haptoglobins also exist which increase enormously the number of individual variants.

The Cholinesterases are enzymes which hydrolyse the esters of choline.

Some people have less than the "normal" amount of them. They can be seriously damaged by certain drugs like suxamethonium, a relaxant.

Hydrazide of isonicotinic acid (INH), introduced into a tuberculous subject, "kills" mycobacteria, after which it is inactivated and eliminated. But its inactivation does not occur at the same rate in everyone; in "slow inactivators" the drug accumulates in the organism until it poisons it.

The pharmaceutical company Bayer has prospered by selling tons of aspirin for decades.*

Does this prove the efficacy and harmlessness of aspirin?

Its efficacy is debatable. As for its harmlessness... Aspirin can literally destroy the stomach of some subjects. Even as suppositories.

If one were to go on writing about individual tolerance to drugs, even to list them all would require a whole book. A general idea must suffice here.

In every case of drug intolerance something is not working properly in the organism, or it works in a different way.

* Aspirin was first sold commercially in 1888. In the USA alone about 20,000 tons are consumed annually (from Illich), equal to about 225 tablets per inhabitant. This gives us an idea of the enormous profits of the pharmaceutical industry. Another example of huge sales is that of tranquillisers and anti-depressants; still in the USA, 10,000 tons of them are consumed each year. (From an article by Giovanni Russo in "Corriere della Sera" of June 7, 1987, p. 3).
See also Dunlop, D.M., "The use and abuse of Psychotropic Drugs" - Proceedings of the Royal Society of Medicine; 63: 1279 (1970).
To get an idea of the profits take as an example Diazepam which is sold under the name of Valium at a price 140 times higher than the original cost. (Burach R.: Official names, prices and sources for patient and doctor. Pantheon Edit., New York (1970).)

But even if one were to content oneself with those few differences given above, how many variations could there be in their combination?

A statistician could do the calculations. It suffices for us to say that possible variations could be numbered in several billions. This is like saying that probably among the four or five billion people who live on the earth no two of them are identical. Just like saying which runs: "There are no two leaves that rustle in the same way." People are like leaves. All are sons of God. But are they all equal? No, they are not.

At this point the vivisector enters the scene. He does not wish to know of differences. He does not wish to know of differences between individuals and he does not wish to know of differences between species. Let us experiment on one species and we will know what will happen on another.

Obviously the vivisector does not express these things so explicitly. He does not even believe them. However, he acts as if he believed them. Indeed, he too knows that the results of experimentation on animals cannot be extrapolated to man and also, strictly speaking, not even can the results of experimentation on one group of humans be applied to all other groups.

The attitude of the vivisector towards animals is clearly contradictory.*

The vivisector claims that:

  1. animals are fundamentally similar to man.
  2. animals are fundamentally different from man.

According to what he finds convenient for his thesis:

  1. animals are similar to man when it is convenient to claim that from animals one can obtain knowledge for man.
  2. animals are different from man when it is convenient to believe that animals do not suffer, are unaware, do not think, and therefore one can do anything with them. Morality simply does not come into the matter.

A question naturally arises here. Are the differences between animal species and individuals of the same species, even at the bio-chemical level, as great as at the macroscopic level? Not at all: to produce conspicuous effects, minimal bio-chemical differences are enough.

Let us take as an example sickle cell disease** (drenpanocytosis).

* The contradiction which forms a convenient screen for the vivisectors has been denounced also by Prof. R. Ryder, the English physiologist, in these words: "On the scientific level experimentation is founded on the similarity between animals and man; on the moral plane it is justified on the basis of the differences between them and by claiming that animals do not feel pain".
** Drepanocytosis: from (Greek) 'threpanon' = sickle. (In English "sickle cell disease"). Drepanocytosis is a hereditary blood disease, mostly occurring in sub-tropical Africa, but also in Greece, Italy, Turkey, India and the Arabian peninsula. In the American continent about 9% of the population of African origin are affected.

The bio-chemical anomaly which causes sickle cell disease is small and concerns haemoglobin. In drepanocytosis (sickle cell disease) of the 572 aminoacids which make up the haemoglobin molecules, only one, glutamic acid, is absent, its place being taken by another (rather similar) aminoacid, valine.*

At first sight this may not seem very significant. Nevertheless.....let us see what such an "insignificant" molecular variation can cause:

1. Some of the red blood corpuscles in these patients do not have the normal discoid shape, but have a sickle shape (see fig. 1 [not repr.]).

2. If the partial pressure of oxygen** is reduced in the blood the number of sickle-shaped red blood corpuscles (drenpanocytes) increases greatly.

3. The presence of drepanocytes in large numbers increases the viscosity of the blood and in consequence the circulation of the blood slows down, resulting in a tendency to acidosis (lowering of the pH). The acidosis favours the destruction of the sickle-shaped red blood corpuscles.

4. The increased viscosity increases the resistance to the blood flow in the vessels. This puts a greater strain on the heart. Moreover, the increased viscosity favours thromboses (especially "microthromboses").

* The resemblance between glutamic acid and valine is evident from their respective formulae:
             COOH                           CH3
              |                              |
             CH2                            CH-CH3
              |                              |
             CH2                            CH-NH2
              |                              |
             CH-NH2                         COOH
             glutamic                       valine
** Partial pressure (or "tension") in the arterial blood is about 100 mm Hg; in venous blood it is about 40 mm Hg. The tendency to assume a sickle shape ("sickle-isation") of the red blood cells occurs in patients with drepanocytic anaemia when the partial pressure of oxygen in the blood is reduced to about 45 mm Hg.
Therefore, under normal circumstances, already in the venous blood.
The partial pressure of oxygen in the blood can be lowered as a result of respiration in a rarified atmosphere (as in high mountains), as a result of violent and prolonged physical exertion, or as a result of lung diseases which depress the oxygenating function of respiration.

5. The sickle-shaped red blood corpuscles are more delicate than normal red blood corpuscles. As a result, intervascular haemolysis (destruction of red blood corpuscles) occurs, and this phenomenon is favoured by acidosis. Haemoglobin, when released, passes into the urine (haemoglobinuria).

6. Due to their fragility the sickle-shaped red blood corpuscles can be destroyed in great numbers by the spleen and other reticulum-endothelial organs (liver, lymph nodes, intestinal wall). Extravascular haemolysis therefore occurs in addition to the intravascular haemolysis already mentioned. The spleen, subjected to more work, becomes enlarged (splenomegaly) and in due course becomes fibrous (due to repeated "micro-thromboses" caused by the increased viscosity of the blood).

7. The micro-thromboses which for the same reason occur in the liver, cause hepatomegaly and, in time, hepatic fibrosis.

8. Similar effects occur in the kidneys resulting in a diminished capacity to concentrate urea. Blood is frequently found in the urine. Haematuria is frequent.

9. The heart suffers as much from micro-thromboses as from the increased work required to keep pumping the hyper-viscous blood. The strain is shown by widening of all four chambers of the heart and this can result in a relative insufficiency of the valves.

10. Similar changes, in the central nervous system, result in cephalea (violent headaches), mental confusion, hemiplegia (paralysis of one side of the body), aphasia (loss of speech), temporary or permanent blindness, paraesthesias of the limbs.

11. Chronic destruction of the red blood corpuscles causes anaemia.

12. Anaemia, chronic and present from birth, slows down body development.

13. Chronic lack of haemoglobin and the resulting hypoxia causes the skin of the legs to ulcerate (due to slowed blood flow). This can result in phlebitis or generalised infections (septicaemia).

14. For the same reasons there is often a characteristic swelling of hands and feet with the possibility of distrophy (undernourishment) and of ulceration of the skin.

15. The blood-producing marrow, having to provide an increased production of blood cells, hypertrophies. This happens at the expense of the bone tissue containing the marrow. The bone becomes abnormally spongy and loses minerals. The outer part becomes thin and liable to fracture. The vertebrae tend to become flattened or biconcave (due to the pressure of the nucleus polposus). Pain can occur in the vertebral column and in all the bones.

We have had fun compiling the incredible list of consequences which can result from the simple substitution, in one single protein, of a molecule of glutamic acid with a molecule of valine.

A mouse has given birth to a mountain. So now let us consider the following: the various animal species are distinguished from one another (and from man) not by only one difference in a single protein: all (or nearly all) proteins of one animal species differ from those of another species. Thus there are millions of proteins. And when one speaks of "protein" the same applies also to "enzymes". And vivisectionists claim that animals all behave alike in response to the same stimulus!

Drug testing uses the greatest number of animals, many millions in a year and of many different species. And this experimentation is handsomely rewarded, not only with honours and titles but also with cash.

Drug testing is carried out principally:

  1. to demonstrate that a particular drug is not toxic.
  2. to demonstrate that the drug works.


That a drug may do no good matters little, at the most it could be considered fraudulent. Almost always, moreover, it has a certain efficacy all the same, as it pleases a lot of people hysterically anxious to consume medicines.

What one should worry about is that it should not be harmful, that is, not poisonous.*

For this reason toxicity tests are carried out on animals, but differences between species, as those indicated in the preceding pages, are not taken into account.

Still less is another factor taken into account:

toxicity tests are almost always carried out on healthy animals whereas the medicine is given to a sick person. But the illness by itself modifies the metabolism of drugs. For instance, fever renders many drugs more toxic: diseases of the liver diminish the capacity of the liver to neutralise dangerous substances; many kidney diseases slow down the elimination of foreign substances like medicines and the products of their degradation.

Immunopathies depress reaction to allergens. A congenital dismetabolism, recognised or hidden, can render toxic a substance which normally is harmless. All these conditions do not exist in the experimental animal or they exist under different aspects and with different consequences.


The majority of human diseases do not afflict any of the most known animals. Then how can one demonstrate in the animal the efficacy of a drug intended for a particular human illness?

If the illness does not normally afflict the animal we have to produce it artificially.

That is relatively easy in the case of infectious diseases, but it is only apparently easy because there are many pitfalls.

* "Toxic" is anything that shortens life or impairs its quality. The concept of toxicity is, however, closely linked to quantity or "dose". Many drugs like digitalis, strophanthin, atropine, are not toxic, on the contrary are beneficial, if they are used in very small doses.
On the other hand, any substance, even the most necessary for life, is harmful in excessive doses. Oxygen, for example, when breathed in at a pressure of more than 20 atmospheres kills in a few minutes. Natural foods (proteins, carbohydrates, fats) consumed in too great amounts lead to obesity and so are "toxic". Obesity does, in fact, shorten life.
Apart from dosage, toxicity is linked to time. For example, hydrocyanic acid (prussic acid) kills in a few seconds; arsenic (according to dose) in a few hours or months; tobacco smoke in years.
Thus we distinguish between acute toxicity and chronic toxicity.

The main pitfall lies in the fact that each animal species reacts differently to the same infection. Here are some examples: monkeys are habitual carriers of the "simian B virus"* which can from time to time cause irritation of the mucus membranes similar to the harmless herpes labialis (cold sore) in man. But the same virus infecting man (from the bite of a monkey or by contamination of a wound by saliva) causes a serious, often fatal illness.

Smallpox virus and yellow fever virus do not affect any known animal.

The rabbit is more susceptible to bovine Mycobacterium tuberculosis than to human Mycobacterium tuberculosis; the guinea-pig reacts in the opposite way. But in neither the guinea-pig nor the rabbit has tuberculosis characteristics comparable with tuberculosis in man.

Mycobacterium leprae (or Hansen's bacillus) is unable to flourish, apart from in man, in only one other animal species, the armadillo, in which it does not, however, arise spontaneously.

The BCG strain of Mycobacterium Tuberculosis of the bovine variety is used, thanks to its relative harmlessness, as a vaccine against tuberculosis. Inoculated into golden hamsters (Microcetus auratus) it causes generalised tuberculosis, with death following in 10-14 months.

Treponema pallidum causes syphilis only in human beings. Inoculated into monkeys it brings about an acute illness which is quite different from that caused in man.

Actinomyces bovis causes a skin disease in cattle, and in human beings an often serious illness of the internal organs. In laboratory animals** it can be cultured only with difficulty and under particular conditions.

The majority of other mycoses (fungal infections) do not give rise to spontaneous diseases in the most common laboratory animals. In order that they should, they must first be inoculated into very sensitive organs like the peritoneum or hyporeactive ones like the central nervous system.

Nocardia, Blastomyces dermatitidis, Balstomyces braziliensis, Coccidioides immitis (very pathogenic for man), Histoplasma capsulatum, Criptococcus neoformans, Geotrichum candidum, Sporotrichum Schenkii, and the Mucorales behaves in this way.

No animal is known to be susceptible to Chromoblastomycosis which is due to various species of fungi, among them being Hormodendrum compactum and Phialifora verrucosa.

* Only in the baboon has the simian B virus never been found.
** The term "laboratory animal" is vague. Any animal can be a laboratory animal, but the choice is made according to practicality and cost rather than according to "scientific" criteria.
If we should find out that the animal with bio-chemical reactions most similar to those of man is, let us suppose, the rhinoceros, would the bulky pachiderm become the most common laboratory animal?
In reality laboratory animals serve ends quite other than scientific ones: they must be easily obtainable, cost little, be easily handled and, if possible, not bite.

Disturbing differences are found in the reaction of many mammals to parasitic metazoans. And what is one to make of the way in which these parasites choose a different host for each phase of their development?

The following is one example among many:

Dicrocoelium dendriticum*, the liver fluke, in its adult stage lives in the intestine of a herbivore (and occasionally of man).

The eggs pass out with excrement into water and are taken in by a snail in which, after two metamorphoses, they become larvae ("cercarie"). The cercarie are deposited on grass where they are eaten by an ant. In the ant they undergo further development to become metacercarie. The ant is eaten with grass by a herbivore (and occasionally by man). In the herbivore (or man) it becomes an adult animal and the cycle begins again.

As is seen, the liver fluke Dicrocoelium specialises in its adult form in living in certain kinds of hosts while its larve (cercarie, metacercarie) are adapted to living in other kinds.

So, Dicrocoelium provides us with a free lesson in the fact that one animal is not worth another, since each animal becomes the wet-nurse at only one stage of its development.

Even fleas are able to distinguish differences between animals. The human flea is Pulex irritans, but the cat flea is Ctenocephalides felis and the dog flea is Ctenocephalides canis. These two latter kinds of flea bite people only occasionally and by mistake.

Hitherto we have considered infectious and parasitic diseases. By inoculating pathogenic agents in animals, the researcher tries to obtain a model of human disease. Illusion or mystification? When we take the wrong road, we avoid looking back in order not to see the truth that could transform us into a statue of salt. And so, having created in an animal an infectious disease which is not the same as that of the human being, the experimenter starts trying out drugs which are supposed to cure it. At this point, the errors multiply in geometric progression, forming an inverted pyramid which cannot stand upright.

The error of studying an artificially created disease is compounded by treating it with a drug which, in all probability, in the animal will be metabolised in a different way than in man. Indeed, different to the point that the animal could die before the infection kills it, just as occurs with penicillin in guinea-pigs.** Besides, it is different because drugs used to combat the infection do not function alone but in synergy with the natural defences.

* Dicrocoelium dendriticum is common in Eastern Europe, in Russia, less so in Africa, in Asia, in North and South America. The adult worm is 5-15 millimetres long and 1.5-2.5 millimetres wide.
** Statement by Sir Howard Florey, (61) joint Nobel Prize winner with Fleming and Chain for the discovery of penicillin: "It was by good luck that in the initial toxicity tests we used mice because if we had used guinea-pigs we would have concluded that penicillin is toxic."

For example, the majority of antibiotics not only stop the multiplication of certain bacteria but also stimulate phagocytosis, that is, the capacity of certain cells (leucocytes, macrophages) to attack and destroy micro-organisms by "eating them up".

However, this capacity for natural defence varies according to different species. An indication of this is given by the different proportions in which different phagocytic cells are found in the blood and in the tissue liquids of different animals and the lack of certain cells in some species. For example, fish and other animals still lower down the evolutionary scale do not possess polymorphonucleate leucocytes and their defence against infection is undertaken by mononucleate cells analogous to monocytes and macrophages of mammals.

In the struggle against infection antibodies are associated with leucocytes:
natural antibodies, which are inherited;
acquired antibodies, which are formed as a result of contact with micro-organisms or with aggressive substances called "antigens".

The presence of acquired antibodies is shown by a hyperactivity which serves to eliminate or neutralise the foreign substance. Beyond certain limits allergies arise in the form of genuine illnesses like bronchial asthma, hay fever, allergic rhinitis and conjunctivitis, nettle rash, erythema nodosum and eczemas.

In animals, too, contact with antigens causes, as in man, the development of antibodies.*

However, it is not possible, even with the most ingenious methods, to reproduce in animals allergies similar to those which afflict so many people.


Is not different behaviour always an expression of more profound biochemical, nervous and psychic differences?

From infections which do not attack animals or do so in a different way than in man, and from immunological phenomena which in animals are never similar to allergic illness found in man, we turn now to another area in which animals differ from man, the "collagenopathies".

The collagenopathies comprise a wide range of manifestations: from rare but fatal diseases like Lupus erythematosus sistemicus or Wegener's granuloma to the most varied diseases which affect the quality of life more than its length, like arteriosclerosis and osteoarthritis.

Old age itself is seen by some as a collagenose disease, because in elderly people collagenous tissue is always "altered" when compared to that of the young.

* It is even suspected that, in humans, allergies to certain drugs may in some cases be due to eating the meat of animals treated with those drugs. This would explain, for example, the allergic reaction to penicillin in certain individuals who claim never to have been treated with penicillin; (but couldn't they have forgotten about it?).

Collagenous tissue exists virtually everywhere in the organism. It is like, in a cloth, the weft, without which it would be impossible to weave the warp. When it changes, the functional capacity of all the organs and all the tissues is impaired.

If it were possible to avoid the ageing of collagen we would be able (so it is said) to prolong life.

So experimental models have to be found.

How can one build, for example, the model for "arteriosclerosis"?

With dogs, fed on a high cholesterol diet or on a diet deficient in cholesterol, or a high lipidic diet or a lipid-deficient diet, or overfed to the point of making the liver burst, or underfed to the point of starvation; dogs made into alcoholics or poisoned with tobacco, dogs overfed with vitamins or deprived of vitamins.

But what do they expect? An arteriosclerotic dog? Such dogs already exist: let it get old and it will get arteriosclerosis just like anyone else.

Those who believe they can understand arteriosclerosis in humans through animal experiments will feel rather annoyed, if not downright indignant, when they examine the bio-chemical characteristics of arteriosclerosis. They look for those dietary factors which cause or favour the development of the disease. They blame diet so obstinately that it makes one think of some hypochondriac seeking revenge on a gourmet.

Eat, eat, and soon you will regret it! Perhaps they are not entirely wrong. If, however, they try to disentangle the confusion analysing the animals, well, here is what they find.

The main culprit, cholesterin, in man is principally esterified by oleic and by stearic acid; in the rat, mainly by arachidonic acid, an essential fatty acid.

A diet containing few calories is good for man but worsens natural arteriosclerosis in rabbits.

The atheromes (degenerative fatty deposits on the walls of the arteries) in man contain high levels of cholesterol and other lipids. The naturally occurring atheromes in the cat and in the rat contain relatively low levels.

The foam-like cells (cells laden with lipids) of human atheromas are altered smooth muscle cells; the foam-like cells of the atheromas of the guinea-pig are monocytes (a third kind of white blood corpuscle with rounded cell nucleus) which have fagocytized lipids.

Compounds which attract particular attention in the study of arteriosclerosis are the lipoproteins, but in humans the VLDL* and the LDL** predominate, while in the majority of primates prevail the HDL.*** It is easy to understand how the above mentioned (and other) differences would frustrate anyone seeking the explanation for human arteriosclerosis in the arteries of animals.

* Very Low Density Lipoproteins
** Low Density Lipoproteins
*** High Density Lipoproteins

Animals also make fools of us when, by using certain drugs to treat arteriosclerosis, we seek to prolong our own life by shortening theirs.

One of these drugs is Clofibrate, which in some animals, apart from being completely harmless, reduces the amount of cholesterol in the blood by about 20%: a resounding success which enabled the drug to be sold by the ton. But how does it actually work in humans?

In humans it not only reduces very slightly the cholesterolemia, but also increases the incidence of heart attacks, damages the liver, the gall bladder and gall duct, sometimes with fatal results.* Truly a splendid success!

Then there are those suffering from osteoarthritis. Why do our joints become so grotesquely (and painfully) deformed?
Dogs, cats, sheep, pigs - let us attempt to mimic our lamenesses on these animals. How can we do it?

Joints beaten with hammer blows, injected with irritating liquids, subjected to ionizing radiation, brutally dislocated.**

What can't be done, when one wants to cause harm? One thing, however, is incomprehensible: that the vivisectors should have such a poor understanding of biology, such a crude conception of life, that they cannot realize that these tortures cause nothing more than fractures, haemorrhages, thromboses, contusions and inflammation. All but an acceptable model of human osteoarthrosis which is a local manifestation of a generalised illness of the collagen.

Nevertheless, the tortures continue. Why? Because the number of animals used in the study of arthrosis is in direct proportion to the amount of anti-arthritic drugs, and to the profits deriving from them.

* In Italy, drugs containing clofibrate were withdrawn from sale in 1979.
** In the Institute of Clinical Orthopedics and Traumatology of the University of Rome, during a lecture, Professor Giorgio Monticelli bent the backs of some dogs in front of the horrified students to illustrate how the vertebral column snaps when it passes a certain angle.
Our indignation is aroused less on account of the miserable victim of such dreadful sadism than on account of the students who were indeed "horrified" but did nothing to stop it.

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Copyright © 1991 by Hans Ruesch Foundation
Excerpted from Prof. Croce's book Vivisection or Science - A Choice to Make (CIVIS, 1991).
To purchase the book contact Hans Ruesch Foundation/CIVIS - POB 152, via Motta 51, CH-6900 Massagno/Lugano, Switzerland