NUTRITION AND GROWTH OF AMPHIBIAN LARVAE 



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

 diets used with amphitian larvae. 



MATERIAIS : 



Biological: Feeding larvae of Anura or Urodela. 



Technical : Foods 

 For the Anura : 



1. Spinach: fresh, green, washed, par-hoiled. { Briggs & Davidson, 19't-2.) 



2. Lettuce: fresh, green, washed, par-boiled. (%iiian, 19'+1.) 



5. Cabbage: fresh, young green leaves, washed, par-boiled. (Borland, 19'+3 . ) 

 k. Banana: very ripe. 



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



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



7. Baw meat (fresh chopped hamburger). 



8. Wheat mixture: (Pratt, 19^+0) 



Ground yellow com ^+6 parts 



Wheat bran 15 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 vltamin-E (Pratt, 19^+0) 



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, I9U0) 



Casein 25^ 



Com starch ^k^o 



Lard 15^ 



Salt mixture h'^ 



Yeast 1.5^ 



Cod liver oil 0,5^ 



11. Liver food (Briggs & Davidson, I9I+2) 



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. Tublfex (red worm). Generally not very clean. 

 h. Frog tadpoles, various sizes. 



5. Meal flies, meal worms, wax moths (Gallerla), fruit flies (Drosophlla), plant 

 lice, small ants. 



6. Baw meat (liver strips). 



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



8. Semi -synthetic diet (Patch, 1941)* 



Purified casein lt-5^ 



Powdered whole milk 57^ 



Cooked cornstarch 



Cod-liver oil 



Baker's yeast 



(* Note: This diet produced cataracts In h(yf> of A. trigrlnum larvae living 2 months, 

 but this effect was counteracted by adding 1.25^ of the total protein of 

 cystine. ) 



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