Vivarium

VIVARIUM (from Latin vivus - living), a facility for various animals where they are kept in more or less natural conditions. In laboratory practice, various species of both warm-blooded and cold-blooded animals are used as laboratory or experimental animals. The necessity of having experimental animals in sufficient quantity for daily work and of corresponding quality (breed, sex, age, weight and size) forces laboratories to have their own V., since animals purchased from outside do not always satisfy these requirements, usually cost more, and there is no guarantee that they have not been previously experimented upon. Proper and cost-effective operation of any V. requires the presence of healthy breeding stock in the facility, rationally designed premises, sufficient equipment and quality feed, as well as an adequate staff of trained personnel. As for the animals themselves, for experimental purposes, those whose maintenance does not require large expenditures and special care, which further reproduce relatively quickly, are not too large, and have a calm disposition are usually used. Therefore, most common use in our laboratories is found: among cold-blooded animals - frogs, and among warm-blooded - dogs, cats, birds, and mainly rabbits, guinea pigs, white rats and white mice; finally, only for special purposes are horses, donkeys, large and small cattle, monkeys, snakes, turtles, etc. used. The main conditions that a rationally designed facility for small laboratory animals must satisfy are as follows. Cages for housing animals must be sufficiently spacious (for rabbits - 70:45:52 cm, for guinea pigs - 50:32:34 cm), well-lit, have good drainage for urine, be convenient for cleaning, fully protected from drafts and dampness, not too bulky and sufficiently inexpensive. The premises itself with cages must be light (windows facing south), warm, dry, well-ventilated, fully protected from various enemies of small animals (rats, cats, dogs, etc.) and convenient for cleaning and disinfection (asphalt floor, walls covered with oil paint). Proper care, frequent cage cleaning, adequate nutrition, periodic renewal of breeding stock by purchasing them from outside, careful observation of pregnant and nursing females with young, timely isolation of sick animals and quarantine housing of animals newly arriving in the facility from outside, sufficiently protect the V. from those devastating epizootics that are often observed in animal facilities. In this respect, particular caution is recommended in the spring and autumn periods, when climatic conditions and changes in diet themselves have a sharp effect on the animal organism. Thus, V., besides the premises for cages with animals, must have a small isolation room, a room for storing feed, and a sheltered from rain area where cages with animals can be taken out on warm summer days, or even a small area in a garden where at least the young could enjoy relative freedom on sunny days. The equipment of the V., besides cages, must include convenient feeders, scales for weighing animals and feed, devices for marking individual animals (paint, stamps, special marks, etc.), thermometers for measuring temperature in experimental animals, a supply of disinfectants, a small first-aid kit, devices for cleaning cages; a root cutter for chopping root vegetables and a stove for burning dead animals and bedding are not superfluous. Finally, a journal for recording animals is necessary, for example, with the following columns: Origin, Sex, Age, Weight, When and Where Sent Out, Notes. Journals must also be kept for breeding animals, as well as statements (monthly, annual) of income and expenditure of live inventory of the V. Regarding feed, the following must be taken into account: quantity must be quite sufficient, but not excessive, spoiled feed products must not be fed to experimental animals, some variety in feed is necessary, animals should be fed sufficiently 2-3 times a day, nursing females and young - at least three times; feed is placed in cages in special feeders and troughs; transition to feeding fresh grass and back should be done gradually; water is given only with exceptionally dry feed (when absent, for example, in the daily portion of root vegetables), as well as to females before giving birth. For rodents, it is not superfluous to place branches or small pieces of wood in cages, which is especially necessary during the period of tooth growth. Rabbits suitable for experiments are of simple breeds, as they are less demanding and resistant to unfavorable life conditions. They are little sensitive to cold, but tolerate dampness poorly. Daily feed portions should consist of hay (or grass), root vegetables and grain products (best is barley). The age of the female put to breeding should be not less than 6-8 months, the male - somewhat older. One male should be kept in the facility for 10-15 females, and for mating the female should be placed in the male's cage, but not vice versa. Duration of pregnancy is 4 weeks, number of young - from 3 to 12 per litter, the period of nursing young by rabbits lasts about 6 weeks, then, after a short rest, the female can be put to the male again. Most common diseases: catarrh of upper respiratory tract, coccidiosis, pseudotuberculosis, mange. Guinea pigs (more correctly, foreign) are sensitive to cold, dampness and sudden temperature changes. Feeding - as for rabbits. Poor reproduction often depends on unsatisfactory nutrition, which is sometimes also the cause of scurvy-like diseases. 10-12 females can be kept together in one cage with one male, but bedding (hay, straw, peat) in this case should be more than, for example, in rabbit cages. Duration of pregnancy is about 10 weeks, nursing period 2-3 weeks, sexual maturity at age 4-6 months, 1-6 young per litter. Mice for experiments are used exclusively white, since gray (domestic), as well as field mice, do not live well in captivity. Feed consists of grain products and bread, but nursing females and young need bread previously soaked in milk. In each cage (box with mesh lid, large jar, etc.) there should be only 1 male for 20 females, but, to avoid mixing of blood, from time to time it is necessary to change the population of different boxes. Pregnancy lasts about 2 weeks, 4-6 young per litter. Rats are kept similarly to mice, but they should be given the opportunity to climb and gnaw in cages. Feed - as for mice, but it is recommended to add raw meat. The tendency to devour their own young is strongly developed in these animals (especially if water is not given in time). Monkeys (mainly various species of macaques) require careful care, are kept in very warm, light and dry premises; cages must be spacious, convenient for catching extremely agile, nimble and strong animals, and have devices for the amusement of monkeys (hanging trapeze, metal mirror, etc.). Feed is very varied, main types: boiled rice, white bread with milk, vegetables and fruits; occasionally give pieces of chalk and onion. Feed thoroughly 2 times a day, but in between frequent small portions of feed are necessary. They are very susceptible to diseases of the respiratory organs and helminthiasis. In laboratory work they are not always safe; special handling techniques are required. Frogs are kept in pools with running (or in vessels with frequently changed) water, into which it is necessary to place bricks or wooden ladders to provide frogs with the opportunity to get out of the water. It is excessive to give food to these animals if the pool where they live has sufficient flora and fauna. Reserves for winter should be made in the warm season of the year. Fish and other aquatic animals are kept in pools with water or in aquariums. The latter should not be too small (best is at least 6 buckets capacity), water in them should be frequently renewed, the ground should be washed and changed not less than once every two months, water should not be poured too cold, vegetation should be in sufficient quantity, dead fish should be removed immediately, feed (bread crumbs, ant eggs, dried meat powder, insect larvae) often, but in small portions. Snakes, turtles, etc. are kept in terrariums (for example, 1 m length, 1/2 m width, 1/2 m height). Many animals can be kept together: grass snakes, salamanders, toads, lizards, turtles. Feed with earth and mealworms, snails, raw scraped meat, flies, cockroaches; snakes need frogs. Birds are kept in cages separately or, better, in common volaries (predators separately); immediately isolate birds that appear sick. Feed: cereals, hemp seed, insects, worms, ant eggs, bread crumbs, etc.; predators should be given raw meat; drinking water is necessary (see also Laboratory animals).