Time filter

Source Type

Plouguerneau, France

van Wormhoudt A.,French Natural History Museum | Gaume B.,French Natural History Museum | Le Bras Y.,French Natural History Museum | Roussel V.,French Natural History Museum | Huchette S.,France Haliotis
Genetica | Year: 2011

Analysis of the 18S rDNA sequences of Haliotis tuberculata tuberculata and H. t. coccinea subtaxa identified two different types of 18S rDNA genes and ITS1 regions. These two different genes were also detected in H. marmorata, H. rugosa and H. diversicolor that are separated from H. tuberculata by 5-65 mya. The mean divergence value between type I and type II sequences ranged from 7. 25% for 18S to 80% for ITS1. ITS1 type II is homologous with the ITS1 consensus sequences published for many abalone species, whereas ITS1 type I presented only minor homology with a unique database entry for H. iris ITS1. A phylogenetic analysis makes a clear separation between type I and type II ITS1 sequences and supports grouping H. t. tuberculata, H. t. coccinea and H. marmorata together. The two subtaxa do not show any significant differences between the homologous 18S rDNA sequences. A general structure of the ITS1 transcript was proposed, with four major helices for the two types. The two genes were expressed and, for the first time, a putative differential expression of ITS1 type I was detected in the gills, digestive gland and gonads whereas ITS1 type II was expressed in all tissues. © 2011 Springer Science+Business Media B.V.

Van Wormhoudt A.,French Natural History Museum | Roussel V.,French Natural History Museum | Courtois G.,University of Las Palmas de Gran Canaria | Huchette S.,France Haliotis
Marine Biotechnology | Year: 2011

Two subspecies of the European abalone have been morphologically recognized: Haliotis tuberculata tuberculata, present in the North Atlantic, and Haliotis tuberculata coccinea, present in the Canary Islands. Among the different nuclear markers used to differentiate these two subspecies, the sperm lysin gene was the most reliable, leading to a 2.2% divergence. Concerning the subunit I of the mitochondrial cytochrome oxydase gene (COI), we observed a difference of 3.3% between the two subspecies. In the North Atlantic, an introgression of mitochondrial DNA from H. tuberculata coccinea to H. tuberculata tuberculata was evident in around 30% of individuals. Due to this difference, we were able to experimentally detect the transfer of paternal mitochondrial DNA (mtDNA) by specific quantitative polymerase chain reaction measurements. The presence of the two mtDNA signatures was also detected in 20% of individuals tested in the field. Moreover, one mt DNA hybrid sequence was identified. The sequencing of this mitochondrial DNA hybrid revealed a mosaic structure with many specific mutations. The origin of this hybrid sequence is discussed. © 2010 Springer Science+Business Media, LLC.

Jolivet A.,University of Western Brittany | Chauvaud L.,University of Western Brittany | Huchette S.,France Haliotis | Legoff C.,Telecom Bretagne | And 4 more authors.
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2015

This study aimed to investigate the environmental controls on the oxygen isotope composition of shells of the European abalone, Haliotis tuberculata. Seasonal δ18O profiles from the outer prismatic layer of four abalone shells, collected live in northwest Brittany (France) in 2002 and 2012, were compared to local temperatures and salinities. According to the findings herein, δ18O variations in abalone shells corresponded to seasonal variations, and thus, shell composition represented a reliable tool for aging and growth studies. Seawater temperatures estimated from the abalone collected in 2012 reflected the in situ measured temperatures, but the reconstructed temperatures from shells of the three specimens collected in 2002 deviated from measured temperatures by 2.5°C. This overestimation of temperatures corresponded to a "kinetic effect" related to very high annual abalone growth rates; thus, it could be corrected by applying +0.53% to the δ18Oshell. This methodology was then applied to a fossil (6000calyr BP) collected in the Bay of Biscay. Given the worldwide distribution of both live and fossilized abalones, the results of the present study showed that this genus represents a promising paleoclimatic tool. We analyzed δ18O composition of modern and fossil abalones. δ18O variations corresponded to seasonal temperature variations. Overestimation of temperatures was related to high growth rates. Paleo and actual seawater temperatures can be reconstructed from δ18O of abalones. © 2015 Elsevier B.V..

Roussel S.,French National Institute for Agricultural Research | Roussel S.,Agro ParisTech | Roussel S.,French National Center for Scientific Research | Huchette S.,France Haliotis | And 2 more authors.
Journal of Sea Research | Year: 2011

The ormer, Haliotis tuberculata is the only European abalone species commercially exploited. The determination of growth and age in the wild is an important tool for fisheries and aquaculture management. However, the ageing technique used in the past in the field is unreliable. The stable oxygen isotope composition (18O/16O) of the shell depends on the temperature and oxygen isotope composition of the ambient sea water. The stable oxygen isotope technique, developed to study paleoclimatological changes in shellfish, was applied to three H. tuberculata specimens collected in north-west Brittany. For the specimens collected, the oxygen isotope ratios of the shell reflected the seasonal cycle in the temperature. From winter-to-winter cycles, estimates of the age and the annual growth increment, ranging from 13 to 55mm per year were obtained. This study shows that stable oxygen isotopes can be a reliable tool for ageing and growth studies of this abalone species in the wild, and for validating other estimates. © 2010 Elsevier B.V.

Vicose G.C.D.,University of Las Palmas de Gran Canaria | Viera M.P.,University of Las Palmas de Gran Canaria | Huchette S.,France Haliotis | Izquierdo M.S.,University of Las Palmas de Gran Canaria
Journal of Shellfish Research | Year: 2012

Settlement of Haliotis tuberculata coccinea larvae was examined in the presence of crustose coralline algae (CCA), Ulvella lens, and Ulva rigida. Germlings of the 2 green macroalgae of different age, enrichment level, and in combination were tested as settlement cues, and CCA was tested as a positive control. Larval settlement was the highest on CCA (61 %) tailed by a 45-day-old mix of U. lens and U. rigida (52%) and 45-day-old U. rigida (46%). Settlement was the lowest (about 3%) on a mix of 4-day-old U. lens and U. rigida and 45-day-old enriched or unenriched U. lens. In all treatments, postlarvae were fed for 4 wk with a mix of diatoms (Amphora sp., Proschkinia sp., Nitzschia sp., and Navicula incerta); postlarval growth was the best on the 45-day-old mix of U. lens and U. rigida. This substrate was also the best of the green macroalgae germlings substrates tested for settlement induction and provided good survival rates. The substrate protein content correlated negatively with larval settlement and survival. The algal cues were differentiated by their fatty acid composition. Fatty acids such as 18:ln-7, 18:2n-6, 16:4n-3, arachidonic acid, and eicosapentaenoic acid were suggested to affect settlement and survival. The fatty acids correlated with settlement were different from the ones associated with survival rates, except eicosapentaenoic acid, which correlated with both. The results of this study show the high value of U. rigida for H. tuberculata postlarvae, and the influence of substrate age on the settlement success. Copyright © 2013 BioOne.

Discover hidden collaborations