caa a22 4500 445340266 CHVBK 20180317142810.0 cr unu---uuuuu 170323e20110901xx s 000 0 eng 10.1007/s00436-011-2319-2 doi (NATIONALLICENCE)springer-10.1007/s00436-011-2319-2 Variation of parasite load and immune parameters in two species of New Zealand shore crabs [Elektronische Daten] [Jessica Dittmer, Anson Koehler, Freddie-Jeanne Richard, Robert Poulin, Mathieu Sicard] While parasites are likely to encounter several potential intermediate hosts in natural communities, a parasite's actual range of compatible hosts is limited by numerous biological factors ranging from behaviour to immunology. In crustaceans, two major components of immunity are haemocytes and the prophenoloxidase system involved in the melanisation of foreign particles. Here, we analysed metazoan parasite prevalence and loads in the two sympatric crab species Hemigrapsus crenulatus and Macrophthalmus hirtipes at two sites. In parallel, we analysed the variation in haemocyte concentration and amount of circulating phenoloxidase (PO) in the haemolymph of the same individuals in an attempt to (a) explain differences in parasite prevalence and loads in the two species at two sites and (b) assess the impact of parasites on these immune parameters. M. hirtipes harboured more parasites but also exhibited higher haemocyte concentrations than H. crenulatus independent of the study site. Thus, higher investment in haemocyte production for M. hirtipes does not seem to result in higher resistance to parasites. Analyses of variation in immune parameters for the two crab species between the two sites that differed in parasite prevalence showed common trends. (a) In general, haemocyte concentrations were higher at the site experiencing higher parasitic pressure while circulating PO activity was lower and (b) haemocyte concentrations were influenced by microphallid trematode metacercariae in individuals from the site with higher parasitic pressure. We suggest that the higher haemocyte concentrations observed in both crab species exposed to higher parasitic pressure may represent an adaptive response to the impact of parasites on this immune parameter. Springer-Verlag, 2011 Dittmer Jessica Laboratoire Ecologie, Evolution, Symbiose, UMR CNRS 6556, Université de Poitiers, 40 avenue du Recteur Pineau, 86022, Poitiers, France aut Koehler Anson Department of Zoology, University of Otago, P.O. Box56, 9054, Dunedin, New Zealand aut Richard Freddie-Jeanne Laboratoire Ecologie, Evolution, Symbiose, UMR CNRS 6556, Université de Poitiers, 40 avenue du Recteur Pineau, 86022, Poitiers, France aut Poulin Robert Department of Zoology, University of Otago, P.O. Box56, 9054, Dunedin, New Zealand aut Sicard Mathieu Laboratoire Ecologie, Evolution, Symbiose, UMR CNRS 6556, Université de Poitiers, 40 avenue du Recteur Pineau, 86022, Poitiers, France aut Parasitology Research Springer-Verlag 109/3(2011-09-01), 759-767 0932-0113 109:3<759 2011 109 436 https://doi.org/10.1007/s00436-011-2319-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00436-011-2319-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Dittmer Jessica Laboratoire Ecologie, Evolution, Symbiose, UMR CNRS 6556, Université de Poitiers, 40 avenue du Recteur Pineau, 86022, Poitiers, France aut NATIONALLICENCE 700 1- Koehler Anson Department of Zoology, University of Otago, P.O. Box56, 9054, Dunedin, New Zealand aut NATIONALLICENCE 700 1- Richard Freddie-Jeanne Laboratoire Ecologie, Evolution, Symbiose, UMR CNRS 6556, Université de Poitiers, 40 avenue du Recteur Pineau, 86022, Poitiers, France aut NATIONALLICENCE 700 1- Poulin Robert Department of Zoology, University of Otago, P.O. Box56, 9054, Dunedin, New Zealand aut NATIONALLICENCE 700 1- Sicard Mathieu Laboratoire Ecologie, Evolution, Symbiose, UMR CNRS 6556, Université de Poitiers, 40 avenue du Recteur Pineau, 86022, Poitiers, France aut NATIONALLICENCE 773 0- Parasitology Research Springer-Verlag 109/3(2011-09-01), 759-767 0932-0113 109:3<759 2011 109 436 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer