4 



RAISING GUINEA PIGS. 



The cost of rearing a guinea i)ig to maturity (age 4 or 5 months) 

 at the department stations lias been estimated by those in charge at 

 from 50 to 60 cents. With their own hxbor, ])rivate breeders, especi- 

 ally farmers mth plenty of green food at command, could probably 

 reduce the cost by half. 



In medical research, especially in testing and standardizing anti- 

 toxins, inmiature animals, weighing 250 grams (nearly 9 ounces) are 

 required. This weight is attamed in about six weeks, and the cost 

 of feeding the animals until suitable for this purpose wiU be corre- 

 spondingly less. Guinea pigs sell at various prices, dependent on 

 supply and demand. The average price for several years has been 

 about 75 cents, but laboratories now report that suitable stock is 

 scarce and that they have been paying from SI to $1.50 for their 

 supply of young animals. Persons favorably situated near cities or 

 institutions requirmg large numbers of guinea pigs should be able to 

 establish a profitable business in supplying them, even at the average 

 price. Aside from laboratory uses there is at present little demand 

 for the animals. 



WILD CAVIES. 



The guinea pig belongs to a family of rodents known as the Cavidse. 

 They are characterized by stout bodies, short incisor teeth, uncleft 

 upper Up, nearly equal limbs, and short or rudimentary tails. The 

 front feet are four-toed, the hind ones three-toed. The family is 

 exclusively South American and includes, besides the true cavies 

 (genus Cavia) , two other living genera, the maras (Patagonian cavies) 

 and the capybara. All are rather closely allied in structure to the 

 rabbits, and in their native habitats are hunted as game. About 20 

 species and races of the genus Cavia have been described. Unlike 

 the domestic cavy, or guinea pig, they all have constant colors and 

 breed but once or twice a year. 



THE DOMESTIC CAVY. 



Of the origin of the domestic cavy little is known. When the 

 Spaniards first invaded the Andean region of South America the 

 animal was found domesticated and living in large numbers in the 

 houses of the Indians, by whom they were used for food. The cavy 

 was carried to Europe by Dutch traders during the sixteenth century. 

 Since then it has been kept in the Old World and in North America 

 chiefly as a pet, and until recently has been generally regarded as an 

 animal of little practical utility. The name '^pig" is readily sug- 

 gested by its form, but the origin of ''guinea'^ as applied to it is 

 unknown, unless the name is a corruption of "Guiana pig.'' 



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