14. NUTRITION AND GROWTH OF 

 AMPHIBIAN LARVAE 



PURPOSE: To determine the effect on the rate of growth and of differentiation of various 

 diets used with amphibian larvae. 



MATERIALS: 



Biological: Feeding larvae of Anura or Urodela. 



Technical : Foods 

 For the Anura : 



1. Spinach: fresh, green, washed, par-boiled. (Briggs & Davidson, 1942.) 



2. Lettuce: fresh, green, washed, par-boiled. (Hyman, 1941.) 



3. Cabbage: fresh, young green leaves, washed, par-boiled. (Borland, 

 1943.) 



4. Banana: very ripe. 



5. Liverwurst; or boiled, dried, and powdered beef liver. 



6. Egg yolk, bacto-beef extract mixed with whole wheat flour. 



7. Raw meat (fresh chopped hamburger). 



8. Wheat mixture: (Pratt, 1940) 



Ground yellow corn 46 parts 



Wheat bran 13 parts 



Wheat middlings 13 parts 



Alfalfa meal 5 parts 



Meat scrap 10 parts 



Dried skim milk 10 parts 



Salt 1 part 



Sardine oil 2 parts 



9. Wheat mixture free of vitamin-E (Pratt, 1940) 



Treat the above #8 mixture with 1% ferric chloride dissolved in ether, 

 soaking it for 12 hours. Distill off the ether and add another portion of 

 sardine oil to replace the vitamin A which is oxidized by the ferrous 

 salts. 



10. Synthetic vitamin E deficient diet: (Pratt, 1940) 



Casein 25% 



Corn starch 54% 



Lard 15% 



Salt mixture 4% 



Yeast 1.5% 



Cod liver oil 0. 5% 



11. Liver food (Briggs & Davidson, 1942) 



Liver, whole wheat, flour, milk. 



For the Urodela : 



1. Daphnia, small and large depending upon stage of larvae. Protozoa. 



2. Enchytrea (white worms); small and large, depending upon size of larvae. 



3. Tubifex (red worm). Generally not very clean. 



4. Frog tadpoles, various sizes. 



5. Meal flies, meal worms, wax moths (Galleria), fruit flies (Drosophila), 

 plant lice, small ants. 



6. Raw meat (liver strips). 



7. Earthworms (after metamorphosis of the Urodele larvae). 



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