CULTURINC OF AMPHIBIAN EMBRYOS 



Parasites are often brought in with living food. These include worms, flies, and mites. 

 However, these infected animals normally comprise the food of most amphibia so that 

 there is little or no danger for them. If Tubifex (red worm) is used as food, it is well to 

 keep them in running cold water for several days because they grow in sewage and are apt 

 to bring in an excess of bacteria. 



Oedema, or swelling of tissues with water, may be due to a malfunctioning of the embry- 

 onic kidneys although it is known to occur even before such organs are developed. Early 

 tadpoles often develop an apparent oedema, but the swelling is due to an accumulation of 

 dissolved gases in the digestive tract with some consequent bloating of the body. General- 

 ized oedema can sometimes be relieved by placing the embryos in slightly hypertonic 

 medium. If the oedema is localized, it can be relieved by puncturing with a needle to al- 

 low the escape of the excess fluid. 



REFERENCES 



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ANDERSON, P L. , 1943 - "The normal development of Triturus pyrrhogaster. " Anat. Rcc. 86:59. 



ARONSON, L. R , 1 944 - "Breeding Xenopus laevis. " Am. Nat. 78:131. 



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