Diets for Animal Experiments [antikvár]

In the course of their researches the physician, the biochemist, and the biologist are often in need of comparing the characteristic features, functions and constituents of the diseased organisms or organs and tissues with data obtained from normál organisms. Therefore, production of model diseases simulating spontaneous humán or animal diseases is more and more frequent today. Since the first experimentál reproduction of beri-beri (polyneuritis gallinarum) at the end of the last century, numerous other diseases have been induced experimentally. A great number of diseases due to vitamin deficiencies can be evoked by alimentary factors (scurvy, rickets, pellagra, achromotrichia, cheilosis, etc.), or by the administration of antimetabolites. Arteriosclerosis and infarctoid cardiopathy can be induced by specific diets. Hypertension can be influenced by nutrition, e.g., through mineral imbalance. Excess of potassium (K) was found to exert a depressing, whereas excess of sodium (Na) an increasing effect on blood pressure. Renal changes and functional disorders can be elicited experimentally by introducing nephrotoxic agents with the food, or by inducing deficiency (e.g., by isoleucine deficit). There are various diets for the experimentál induction of different forms of anaemia, hypoproteinaemia, pancreatic and hepatic lesions, etc., such as protein deficiency, methionine deficiency, various forms and degrees of starvation, administration of hepatotoxic and pancreatotoxic agents, etc. Even bronchiectasis can be evoked by appropriate diets. Different forms of dystrophy are likewise reproducible by dietary means. The digestive system shows a lively reaction to effects of the diet, e.g., the development of neurogenic gastric ulcer can be stimulated, inhibited or prevented by means of various diets. Similarly, by applying appropriate diets the formation of megacecum and megacolon, and even Kwashiorkor-like symptoms can be elicited. For the study of certain diseases of dentition we can induce dental caries and parodontosis in the experimentál animals. There are methods to produce diseases üke osteoporosis, osteo- and neurolathyrism, myelopathy, encephalomalacia, myelitis marginalis, etc. Pathological conditions due to hormonal disorders, such ashypo- andhyperthyroidism, haematological anomalies, lymphoid hyperplasia, etc., can be reproduced by specific alimentation. Animal dietetics, i.e., nutrition of experimentál animals is therefore an important branch of nutritional science. By adequate diets we can maintain the control animals in healthy condition or by other intentional diet we can produce certain pathologic states. Nutrition of experimentál animals was based on experiences gained with domestic animals. Attempts have been made to express the optimál level