Effects of killing, fixing and mounting methods on taxonomic characters of parthenogenetic adult female Caenorhabditis elegans (Nematoda : Rhabditidae)
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چکیده
A comparative study of several commonly-used killing, f i i g and mounting techniques was made to identify the optimum procedure for preparation of parthenogenetic adult female Caenorhabditis elegans for taxonomic examination. Nematodes were either 9 killed in hot water (95 OC) and fixed in cold fixative (22 "C) or iz) killed and fiied in hot fixative by Seinhorst's (1966) technique. Both the qualitative and quantitative effects of five fixatives (FA 4:l; FP 4:l; TAF; FG and FAA) on each of twenty body characteristics were studied in temporary mounts of specimens killed by each method. Although al1 the fiiatives caused significant shrinkage and/or distortion, killing and fiing in hot TAF (95 OC) produced the least-affected specimens. Subsequent processing of hot TAF-killed and -fiied specimens to lactophenol or glycerol caused further significant shrinkage and/or distortion. Of the four techniques studied, processing of nematodes to glycerol by the slow method affected fewest parameters and produced the most acceptable specimens.
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