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The starry smooth-houndMustelus asteriasis a near-threatened coastal shark in Europe, whose parasitofauna is largely unknown. We studied metazoan parasites of 20 immature sharks (13 males and seven females) from the English Channel and we examined their relationships with host condition and their use as host bioindicators. All the sharks were parasitized by one to six metazoan taxa among the twelve recorded in the whole sampling (one trematode, six cestodes and two nematodes trophically-transmitted; one monogenean, one copepod and one myxosporean on gills), with a mean abundance of 30.5 ± 21.4 parasites per fish (myxosporeans not included). The three major taxa were in decreasing order: the nematodeAcanthocheilus rotundatus(prevalence: 75%, Confidence Interval 53–89%), the cestodeEutetrarhynchussp. (70%, CI 48–85%), and the monogeneanErpocotyle laevis(60%, CI 39–78%). The gill copepodKroyeria lineataand the gut nematodeProleptus obtususwere identified as significant pathogens. Parasite community differed between males and females despite their immature stage, suggesting early spatial sex-segregation, withE. laevis,Eutetrarhynchussp. andAnthobothriumsp. proposed as tags. We discuss results in terms of host fitness loss and information given by parasites on diet ecology and stock discrimination. We recommend incorporating parasitology in further research to improve shark conservation and management.

This review describes analytical methods developed for the separation, identification and quantitation of trans-isomers of unsaturated fatty acids. Although these methods are applicable to a wide variety of food matrices, we have particularly emph a- sised the analysis of trans unsaturated fatty acids in milk fat. Various methods are described such as infrared spectroscopy, direct gas chromatography, gas chromatography in combination with either thin-layer chromatography or liquid chromatography both impregnated with silver nitrate and gas chromatography coupled with mass spectrometry. The field of application, the advantages and the drawbacks of each method are evaluated and discussed.