Nutritional Studies on Screw-Worm Larvae with Chemically Defined Media
| Autor: | Richard E. Gingrich |
|---|---|
| Rok vydání: | 1964 |
| Předmět: | |
| Zdroj: | Annals of the Entomological Society of America. 57:351-360 |
| ISSN: | 1938-2901 0013-8746 |
| Popis: | For rearing larvae of the screw-worm, Cochliomyia hominivorax (Coquerel) (Diptera: Calliphoridae), a synthetic medium was developed that contained casein, yeast extract, cholesterol, inorganic salts, water, and agar. This medium was further defined by replacement of casein with a mixture of L-isomer amino acids, and of yeast extract with a mixture of vitamins and ribonucleic acid. Larval growth and development on the defined medium were nearly equal to those on media containing casein and yeast. Further studies on individual requirements showed that larvae absolutely required thiamine, riboflavin, pantothenate, niacin, and choline for growth; that biotin and folic acid stimulated growth and were necessary for maturation to the adult stage; and that pyridoxine (and its analogs pyridoxal and pyridoxamine), inositol, B12, and carnitine had no effect on growth. Niacinamide replaced niacin, but p -aminobenzoic acid had no effect on the folic acid requirement. Larvae failed to grow in the absence of arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, threonine, tryptophane, and valine. Cystine and glycine were required for normal growth. Ornithine or citrulline could not be substituted for arginine, homocystine or cysteine for methionine, nor hydroxy-proline for proline. The larva requirement for cholesterol could not be satisfied by dihydroxycholesterol, ergesterol, or β-sitosterol. Addition of corn, safflower, or cod liver oils inhibited growth, possibly by mechanical stresses. Choline was replaced by lecithin, but not by betaine, ethanolamine, or carnitine. Ribose, glucose, and maltose added to the diet inhibited growth, but glycogen and starch at ½% levels did not. The inhibition from saccharides of low molecular weight appeared to result from osmotic stresses. RNA was essential for larval growth, but could be replaced by a mixture of adenine, cytosine, and guanine. Uracil and uradylic acid inhibited growth. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|