![]() | Experimental evaluation of co-culture of juvenile sea cucumbers, Holothuria scabra (Jaeger), with juvenile blue shrimp, Litopenaeus stylirostris (Stimpson) Auteur(s) : Purcell, S Patrois, Jacques Fraisse, N Éditeur(s) : Blackwell science Résumé : The co-culture of juvenile sea cucumber Holothuria scabra (Jaeger), or 'sandfish', with juvenile blue shrimp Litopenaeus stylirostris (Stimpson) was tested by growing groups in co-culture and monoculture for 3 weeks in tanks with enriched sand substratum. Feed was supplied on trays, accessible only to shrimp. Survival of shrimp and sandfish was high in all treatments (73-100%). Growth of shrimp did not differ between monoculture and co-culture, but sandfish grew significantly slower in co-culture (P=0.03), although their sand burying and surface foraging were apparently unaffected by shrimp (P=0.76). However, shrimp increased the levels of total ammonia-N in tanks, which related inversely with sandfish growth (P=0.04). Conversely, sandfish did not appear to lower the water quality for shrimp culture. While sandfish bioturbate sediments and eat organic deposits, the juveniles did not significantly reduce the organic content of sand in tanks. Co-culturing juveniles of the two species in earthen ponds appears feasible, with no detriment to shrimp production, presenting a cost-effective method for growing sandfish to larger sizes for restocking. These findings underpin further studies to test the viability of commercial co-culture of sandfish with blue shrimp at later stages in the production cycle of shrimp. Aquaculture Research (1355-557X) (Blackwell science), 2006-03 , Vol. 37 , N. 5 , P. 515-522 Droits : 2006 Blackwell Publishing, Inc. http://archimer.ifremer.fr/doc/2006/publication-1356.pdf DOI:10.1111/j.1365-2109.2006.01458.x http://archimer.ifremer.fr/doc/00000/1356/ | Partager |
![]() | Experimental assessment of oyster transfers as a vector for macroalgal introductions Auteur(s) : Mineur, Frederic Belsher, Thomas Johnson, Mark P. Maggs, Christine A. Verlaque, Marc Éditeur(s) : Elsevier Résumé : Introduction of non-indigenous species can alter marine communities and ecosystems. In shellfish farming, transfer of livestock, especially oysters, is a common practice and potentially constitutes a pathway for non-indigenous introductions. Many species of seaweeds are believed to have been accidentally introduced in association with these transfers, but there is little direct evidence. We experimentally simulated the transfer of oysters from the Thau Lagoon (France). These transfers involved increasing periods of aerial emersion and additional brine and hot water treatments. The brine and hot water treatments were evaluated as a means of reducing the probability of algal introductions with oyster transfers. Shells were cultured for 40 days in experimental tanks to identify the macroalgae likely to be introduced with any oyster transfer. A total of 57 macroalgal taxa, including 16 taxa not indigenous to the Thau Lagoon, were recorded across all treatments and experiments. The abundance of some species increased in several cases following aerial emersion. Elimination treatments (immersion in brine or hot water) significantly reduced algal diversity, with hot water treatments resulting in no species or only tubular Ulva spp. present. The results support the hypothesis that oyster transfers are effective as primary and secondary vectors of macroalgal introductions. Relatively simple changes to the transfer practice (particularly hot water treatments) are suggested as a means of reducing the risk of non-indigenous algal introductions. Biological Conservation (0006-3207) (Elsevier), 2007-06 , Vol. 137 , N. 2 , P. 237-247 Droits : 2007 Elsevier Ltd All rights reserved. http://archimer.ifremer.fr/doc/2007/publication-2779.pdf DOI:10.1016/j.biocon.2007.02.001 http://archimer.ifremer.fr/doc/00000/2779/ | Partager Voir aussi Elimination treatments Transport Marine macrophytes Thau Lagoon Shells Crassostrea gigas Biological invasions Télécharger |
![]() | Sound production in Sciaenops ocellatus: Preliminary study for the development of acoustic cues in aquaculture Auteur(s) : Parmentier, Eric Tock, Jeremy Falguiere, Jean-claude Beauchaud, Marilyn Éditeur(s) : Elsevier Science Bv Résumé : The red drum Sciaenops ocellatus is an estuarine-dependent sciaenid that has supported important recreational and commercial fisheries for many years. Since the 1980s, this species has been farmed in different regions of the world and studies have been conducted to find natural ways to improve its culture. Sciaenops ocellatus is well known for making calls but studies on this characteristic have been mainly restricted to passive acoustics. The aim of this study was to provide acoustic-related information that could be useful in rearing practices. We have studied in detail fish calling characteristics, described their sound-producing mechanism and tested the recordings in different kinds of confinements (floating cages, concrete and fibreglass tanks). Contrary to previous studies, calls were recorded mainly in the morning, between 06:00 and 09:00. Sounds are made only by males; females do not have sound-producing apparatus. The anatomy, muscle ultrastructure data and calling characteristics show conclusively that calls result from the contraction of high speed muscles which are characterized by the very small diameter (7 μm) of the muscle cells. Preliminary results suggest sound characteristics can give information on the fish physiology but further studies are needed. The effects of resonance of fibreglass tanks are experimentally highlighted, showing unequivocally that all the characteristics of fish calls are completely distorted, even in big tanks (13 m3). These findings should be taken into account when using pre-recorded sounds in the rearing of this species because it can affect communication during courtship activity. Aquaculture (0044-8486) (Elsevier Science Bv), 2014-08 , Vol. 432 , P. 204-211 Droits : 2014 Elsevier B.V. All rights reserved http://archimer.ifremer.fr/doc/00190/30127/28589.pdf DOI:10.1016/j.aquaculture.2014.05.017 http://archimer.ifremer.fr/doc/00190/30127/ | Partager |
![]() | Feasibility of polyculture of blue shrimp Litopenaeus stylirostris and goldlined rabbitfish Siganus lineatus in a mesocosm system Auteur(s) : Luong, Trung Cong Hochard, Sebastien Royer, Florence Lemonnier, Hugues Letourneur, Yves Éditeur(s) : Elsevier Science Bv Résumé : The study was conducted to (1) estimate the effects of polyculture of blue shrimp Litopenaeus stylirostris with goldlined rabbitfish Siganus lineatus on production, environmental quality and water and sediment metabolism and (2) to determine if blue shrimp and goldlined rabbitfish polyculture is possible. The experiment was carried out for 12 weeks in a mesocosm system that consisted of 12 circular outdoor mesocosm fiberglass tanks (1.7 m2, 1275 L water volume). Shrimp (2.9 g) were randomly stocked at density of 15 shrimp.m− 2 without rabbitfish (control), with rabbitfish (25.5 g) at low density (1.2 fish.m− 2) (LDRB) and high density (2.4 fish.m− 2) (HDRB). Results indicated that goldlined rabbitfish S. lineatus did not affect shrimp growth performance. At the end of the experiment, the combined shrimp and rabbitfish yields in the LDRB (213 g.m− 2) treatment and the HDRB (295 g.m− 2) treatment were significantly greater (P < 0.05) than the shrimp yield in the control (143 g.m− 2). Most of the water and sediment parameters were similar among treatments. There was no significant difference (P > 0.05) in gross primary productivity and respiration between the HDRB treatment and the control. It was concluded that the polyculture of blue shrimp with goldlined rabbitfish is technically possible without degradation of the environment in the culture system. Aquaculture (0044-8486) (Elsevier Science Bv), 2014-09 , Vol. 433 , P. 340-347 Droits : 2014 Elsevier B.V. All rights reserved. http://archimer.ifremer.fr/doc/00198/30968/29344.pdf DOI:10.1016/j.aquaculture.2014.06.014 http://archimer.ifremer.fr/doc/00198/30968/ | Partager |
![]() | Vibriosis induced by experimental cohabitation in Crassostrea gigas: Evidence of early infection and down-expression of immune-related genes Auteur(s) : De Decker, Sophie Saulnier, Denis Éditeur(s) : Academic Press Ltd- Elsevier Science Ltd Résumé : The understanding of reciprocal interactions between Crassostrea gigas and Vibrio sp., whether these be virulent or avirulent, is vital for the development of methods to improve the health status of cultured oysters. We describe an original non-invasive experimental infection technique using cohabitation, designed to explore these interactions. Using real-time PCR techniques we examined the dynamics of virulent and avirulent Vibrio sp. in oyster hemolymph and tank seawater, and made a parallel study of the expression of four genes involved in oyster immune defense: Cg-BPI, Cg-EcSOD, Cg-IκB, Cg-TIMP. No mortality occurred in control animals, but oysters put in cohabitation for 2–48 h with animals previously infected by two Vibrio pathogens suffered mortalities from 2 to 16 days post-cohabitation. Our results show that virulent Vibrio infect healthy individuals after only 2 h of cohabitation, with values ranging from 4.5×102 to 2×104 cells ml−1 hemolymph. Simultaneously, an approximate ten-fold increase of the total Vibrio population was observed in control animals, with a 6.6–78.5-fold up-expression of targeted genes. In contrast, oysters exposed to harmful bacteria had mean expression levels strongly down-regulated by a factor of 9.2–29 (depending on the gene) compared with control animals. Although oysters were still found to be infected by virulent Vibrio after 6–48 h of cohabitation, no significant differences were noted when comparing levels of each transcript in control and infected oysters at the same sampling times during this period: the important differences were noted before 6 h cohabitation. Taken together, our data support (1) the hypothesis that virulent Vibrio disturbs the immune response of this invertebrate host both rapidly and significantly, although this occurs specifically during an early and transient period during the first 6 h of cohabitation challenge, and that (2) expression of targeted genes is not correlated with vibriosis resistance. Fish & Shellfish Immunology (1050-4648) (Academic Press Ltd- Elsevier Science Ltd), 2011-02 , Vol. 30 , N. 2 , P. 691-699 Droits : 2011 Elsevier Ltd All rights reserved. http://archimer.ifremer.fr/doc/00025/13604/10681.pdf DOI:10.1016/j.fsi.2010.12.017 http://archimer.ifremer.fr/doc/00025/13604/ | Partager Voir aussi Oyster-Vibrio interactions Pathogenesis Immune response Non-invasive experimental challenge Real-time PCR Télécharger |
![]() | Snook (Centropomidae) and grouper (Serranidae) mariculture in the Gulf of Mexico and Caribbean Basin Auteur(s) : Roberts Jr, D Éditeur(s) : Actes de colloques Ifremer, Tahiti, French Polynesia, 20 Feb - 4 Mar 1989, n°9, chap. 44, pp.485 Résumé : Centropomidae and Serranidae, sometimes collectively misnamed "sea basses", are suitable for aquaculture in pens, ponds, and raceways around the tropical and subtropical latitudes of the world. Western Atlantic Ocean species were recently considered for farming. South Florida, Mexico, Central and South America and the Antilles areas of the Caribbean Basin have extensive areas suitable for farming groupers and snook. Principal species of interest are the common snook (Centropomus undecimalis ), the fat snook (C. parallelus ), the Nassau grouper (Epinephelus striatus ), Black seabass (Centropristis striatus ), Gag (Mycteroperca microlepis ), and jewfish (E. itajara ). Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/1989/acte-1477.pdf http://archimer.ifremer.fr/doc/00000/1477/ | Partager |