CARE AND FEEDING OF LABORATORY FISH 349 



2. Animal material - 



Artemia - the brine shrimp eggs can be purchased (Brine Shrimp Sales Co. , 

 1655 West Winton Ave. , Haywood, Calif. ) in large numbers and raised in salt 

 solutions. Day old brine shrimp are excellent food for fish fry. (See Demp- 

 ster 1953) 



Daphnia - and other small Crustacea are very good. Can be sifted out so that 

 smaller specimens are given to fry of 3 weeks or older. Carapace of older 

 specimens may be harmful to young fish. (See U. S. Fish & Wildlife Serv. 

 FL #331) 



Drosophila - the common fruit fly used in Genetics courses, a natural food 

 which can be raised easily in the laboratory. Vestigial mutant is preferred. 



Earthw orms - generally too large but may be cut or chopped up. 



Euchytrea - white worms, excellent, even good for fry when finely chopped. 

 These may be cultured in damp humus, in a cool and dark environment by 

 feeding them on milk-soaked bread once each week. Cover the humus with a 

 glass plate to reduce evaporation and, if possible, pass cold running water 

 through glass tubing submerged in the humus, to keep the culture moist and 

 cool. Allow one month for the culture to get started after inoculation. 



Infusoria - (Protozoa) inadequate for adult fish but excellent for carrying fry 

 through critical first 3 weeks after hatching. Raise on hay infusions and add 

 in small amounts to fry tank. 



Mealworms - particularly good for fish when chopped fine. 



Mosquito larvae - a natural food, excellent. 



Tubifex - the red worm used most commonly. This is a sewage worm and can 

 be handled by adult fish but should not be a steady diet. Should be kept in 

 running cold water to reduce incidence of transmitting parasites to fish. 

 (See "Culture Methods for Invertebrate animals. " Dover Pub. , 180 Varick, N. Y. C. ) 



Prepared Foods: 

 Ant eggs 



Baby fish food, powdered for fry 

 Beef, shredded 



Cereals - fine grained varieties 

 Clams, chopped finely 

 Daphnia, dried 

 Dried flies 



Egg, hard boiled yolk 

 Lacto-Peop (see Tricker) 

 Lettuce, wilted 

 Lobster; canned and shredded 

 Oysters, chopped finely 

 Potato, boiled or baked white 

 Salmon, dried and dried eggs 

 Shrimp; canned, shredded or dried 

 Spinach, partially cooked 



Oatmeal, cooked with or without dried shrimp 

 (And a large variety of powdered foods in any 10 cent store or pet shop). 



It is even possible to make up a home-made mixture which contains all of the necessary 

 ingredients. Take one can each of dog food, shrimp, and salmon; add a can of meat 

 scraps and grind all together with 1 lb. of partially cooked spinach through a fine meat 

 chopper. Spread the mixture out thinly on heavy brown paper and place in the direct sun- 

 light until thoroughly dry. Regrind when dried, through finest coffee grinder. The sun 

 will kill any parasites and may add some vitamin value, or a small amount of cod liver 

 meal may be added to the above for vitamins. This mixture should be stored in stoppered 

 bottles in the refrigerator. It should be made fresh every two weeks. 



