B C Coull | PubMed Health

PubMed1997

An efficient DNA extraction method for small metazoans.

The isolation of total nucleic acids from small metazoan taxa is difficult and often leads to an unacceptably large percentage of unsuccessful polymerase chain reaction (PCR) amplifications. Our work with the evolutionary genetics of harpacticoid copepods was an incentive to refine techniques such that consistent amplifications from minute marine organisms were feasible. We describe these modifications and demonstrate their utility for the amplification of multiple loci from single harpacticoid copepods.

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PubMed1992

Reproductive output of a meiobenthic copepod exposed to sediment-associated fenvalerate.

The benthic harpacticoid copepod, Amphiascus tenuiremis, was cultured through one generation at four concentrations (600, 300, 150, and 0 micrograms/kg) of sediment-associated fenvalerate, a synthetic pyrethroid insecticide, to assess effects on reproductive output and age structure. Two static renewal experiments with four replicates of each treatment were conducted. At the end of 21 days, surviving copepods were sorted and counted into adult males, adult females, copepodites, and nauplii. Fenvalerate was extracted from the sediment and measured by GC-MS. The number of individuals in each life-history stage in fenvalerate treatments was not significantly different from controls, except for increased adult females in fenvalerate in the second experiment. The overall lack of a fenvalerate toxic effect on A. tenuiremis was most likely because fenvalerate tightly binds to sediments and was probably not bioavailable to the copepods. Sediment-associated pesticides with large octanol:water partitioning coefficients (K(ow)'s) such as fenvalerate appear to be less toxic to infaunal copepods than those exhibiting smaller K(ow)'s.

Animals↗