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Wijgerde T, van Ballegooijen M, Nijland R, van der Loos L, Kwadijk C, Osinga R, Murk A, Slijkerman D. Adding insult to injury: Effects of chronic oxybenzone exposure and elevated temperature on two reef-building corals. Sci Total Environ 2020; 733:139030. [PMID: 32446051 DOI: 10.1016/j.scitotenv.2020.139030] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/21/2020] [Accepted: 04/25/2020] [Indexed: 05/20/2023]
Abstract
Coral bleaching due to global warming currently is the largest threat to coral reefs, which may be exacerbated by altered water quality. Elevated levels of the UV filter oxybenzone in coastal waters as a result of sunscreen use have recently been demonstrated. We studied the effect of chronic oxybenzone exposure and elevated water temperature on coral health. Microcolonies of Stylophora pistillata and Acropora tenuis were cultured in 20 flow-through aquaria, of which 10 were exposed to oxybenzone at a field-relevant concentration of ~0.06 μg L-1 at 26 °C. After two weeks, half of the corals experienced a heat wave culminating at 33 °C. All S. pistillata colonies survived the heat wave, although heat reduced growth and zooxanthellae density, irrespective of oxybenzone. Acropora tenuis survival decreased to 0% at 32 °C, and oxybenzone accelerated mortality. Oxybenzone and heat significantly impacted photosynthetic yield in both species, causing a 5% and 22-33% decrease, respectively. In addition, combined oxybenzone and temperature stress altered the abundance of five bacterial families in the microbiome of S. pistillata. Our results suggest that oxybenzone adds insult to injury by further weakening corals in the face of global warming.
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Affiliation(s)
- Tim Wijgerde
- Wageningen University and Research, Marine Animal Ecology, P.O. Box 338, 6700 AH Wageningen, the Netherlands
| | - Mike van Ballegooijen
- Wageningen University and Research, Marine Animal Ecology, P.O. Box 338, 6700 AH Wageningen, the Netherlands
| | - Reindert Nijland
- Wageningen University and Research, Marine Animal Ecology, P.O. Box 338, 6700 AH Wageningen, the Netherlands
| | - Luna van der Loos
- Wageningen University and Research, Marine Animal Ecology, P.O. Box 338, 6700 AH Wageningen, the Netherlands
| | - Christiaan Kwadijk
- Wageningen University and Research, Wageningen Marine Research, P.O. Box 68, 1970 AB IJmuiden, the Netherlands
| | - Ronald Osinga
- Wageningen University and Research, Marine Animal Ecology, P.O. Box 338, 6700 AH Wageningen, the Netherlands
| | - Albertinka Murk
- Wageningen University and Research, Marine Animal Ecology, P.O. Box 338, 6700 AH Wageningen, the Netherlands
| | - Diana Slijkerman
- Wageningen University and Research, Wageningen Marine Research, P.O. Box 57, 1780 AB Den Helder, the Netherlands.
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Gökalp M, Kooistra T, Rocha MS, Silva TH, Osinga R, Murk AJ, Wijgerde T. The Effect of Depth on the Morphology, Bacterial Clearance, and Respiration of the Mediterranean Sponge Chondrosia reniformis (Nardo, 1847). Mar Drugs 2020; 18:E358. [PMID: 32664196 PMCID: PMC7401281 DOI: 10.3390/md18070358] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/01/2020] [Accepted: 07/03/2020] [Indexed: 11/16/2022] Open
Abstract
To support the successful application of sponges for water purification and collagen production, we evaluated the effect of depth on sponge morphology, growth, physiology, and functioning. Specimens of Eastern Mediterranean populations of the sponge Chondrosia reniformis (Nardo, 1847) (Demospongiae, Chondrosiida, Chondrosiidae) were reciprocally transplanted between 5 and 20 m depth within the Kaş-Kekova Marine Reserve Area. Control sponges at 5 m had fewer but larger oscula than their conspecifics at 20 m, and a significant inverse relationship between the osculum density and size was found in C. reniformis specimens growing along a natural depth gradient. Sponges transplanted from 20 to 5 m altered their morphology to match the 5 m control sponges, producing fewer but larger oscula, whereas explants transplanted from 5 to 20 m did not show a reciprocal morphological plasticity. Despite the changes in morphology, the clearance, respiration, and growth rates were comparable among all the experimental groups. This indicates that depth-induced morphological changes do not affect the overall performance of the sponges. Hence, the potential for the growth and bioremediation of C. reniformis in mariculture is not likely to change with varying culture depth. The collagen content, however, was higher in shallow water C. reniformis compared to deeper-growing sponges, which requires further study to optimize collagen production.
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Affiliation(s)
- Mert Gökalp
- Marine Animal Ecology Group, Wageningen University and Research, P.O. Box 338, 6700 AH Wageningen, The Netherlands; (T.K.); (R.O.); (A.J.M.); (T.W.)
| | - Tjitske Kooistra
- Marine Animal Ecology Group, Wageningen University and Research, P.O. Box 338, 6700 AH Wageningen, The Netherlands; (T.K.); (R.O.); (A.J.M.); (T.W.)
| | - Miguel Soares Rocha
- 3B’s Research Group, I3Bs–Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, Parque de Ciência e Tecnologia, Zona Industrial da Gandra, 4805-017 Barco, Guimarães, Portugal; (M.S.R.); (T.H.S.)
- ICVS/3B’s–PT Government Associate Laboratory, 4806-909 Braga/Guimarães, Portugal
| | - Tiago H. Silva
- 3B’s Research Group, I3Bs–Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, Parque de Ciência e Tecnologia, Zona Industrial da Gandra, 4805-017 Barco, Guimarães, Portugal; (M.S.R.); (T.H.S.)
- ICVS/3B’s–PT Government Associate Laboratory, 4806-909 Braga/Guimarães, Portugal
| | - Ronald Osinga
- Marine Animal Ecology Group, Wageningen University and Research, P.O. Box 338, 6700 AH Wageningen, The Netherlands; (T.K.); (R.O.); (A.J.M.); (T.W.)
| | - AlberTinka J. Murk
- Marine Animal Ecology Group, Wageningen University and Research, P.O. Box 338, 6700 AH Wageningen, The Netherlands; (T.K.); (R.O.); (A.J.M.); (T.W.)
| | - Tim Wijgerde
- Marine Animal Ecology Group, Wageningen University and Research, P.O. Box 338, 6700 AH Wageningen, The Netherlands; (T.K.); (R.O.); (A.J.M.); (T.W.)
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Tilstra A, Wijgerde T, Dini-Andreote F, Eriksson BK, Salles JF, Pen I, Osinga R, Wild C. Light induced intraspecific variability in response to thermal stress in the hard coral Stylophora pistillata. PeerJ 2017; 5:e3802. [PMID: 29038747 PMCID: PMC5640979 DOI: 10.7717/peerj.3802] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 08/23/2017] [Indexed: 11/20/2022] Open
Abstract
Recent research suggests that prior exposure of several months to elevated irradiance induces enhanced thermal tolerance in scleractinian corals. While this tolerance has been reported at the species level, individual coral colonies may react differently due to individual variability in thermal tolerance. As thermal anomalies are predicted to become common in the upcoming future, intraspecific variation may be key to the survival of coral populations. In order to study light-history based thermal stress responses on individual colonies, we developed a preliminary microcosm experiment where three randomly chosen, aquacultured colonies of the model coral Stylophora pistillata were exposed to two irradiance treatments (200 and 400 μmol photons m-2 s-1) for 31 days, followed by artificially induced heat stress (∼33.4 °C). We found different responses to occur at both the intraspecific and the intracolonial levels, as indicated by either equal, less severe, delayed, and/or even non-necrotic responses of corals previously exposed to the irradiance of 400 compared to 200 μmol photons m-2 s-1. In addition, all individual colonies revealed light-enhanced calcification. Finally, elevated irradiance resulted in a lower chlorophyll a concentration in one colony compared to the control treatment, and the same colony displayed more rapid bleaching compared to the other ones. Taken together, this study highlights the potential importance of intra-individual variability in physiological responses of scleractinian corals and provides recommendations for improving methodological designs for future studies.
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Affiliation(s)
- Arjen Tilstra
- Department of Marine Benthic Ecology & Evolution, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
- Marine Ecology Group, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
| | | | - Francisco Dini-Andreote
- Microbial Ecology cluster, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
| | - Britas Klemens Eriksson
- Department of Marine Benthic Ecology & Evolution, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
| | - Joana Falcão Salles
- Microbial Ecology cluster, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
| | - Ido Pen
- Theoretical Research in Evolutionary Life Sciences, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
| | - Ronald Osinga
- Marine Animal Ecology Group, Wageningen University & Research, Wageningen, The Netherlands
| | - Christian Wild
- Marine Ecology Group, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
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Osinga R, Derksen-Hooijberg M, Wijgerde T, Verreth JAJ. Interactive effects of oxygen, carbon dioxide and flow on photosynthesis and respiration in the scleractinian coral Galaxea fascicularis. J Exp Biol 2017; 220:2236-2242. [DOI: 10.1242/jeb.140509] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 04/02/2017] [Indexed: 11/20/2022]
Abstract
Rates of dark respiration and net photosynthesis were measured on six replicate clonal fragments of the stony coral Galaxea fascicularis (Linnaeus 1767), which were incubated under twelve different combinations of dissolved oxygen (20%, 100% and 150% saturation), dissolved carbon dioxide (9.5 and 19.1 μmol L−1) and water flow (1-1.6 cm s−1 versus 4-13 cm s−1) in a repeated measures design. Dark respiration was enhanced by increased flow and increased oxygen saturation in an interactive way, which relates to improved oxygen influx into the coral tissue. Oxygen saturation did not influence net photosynthesis: neither hypoxia nor hyperoxia affected net photosynthesis, irrespective of flow and pH, which suggests that hyperoxia does not induce high rates of photorespiration in this coral. Flow and pH had a synergistic effect on net photosynthesis: at high flow, a decrease in pH stimulated net photosynthesis by 14%. These results indicate that for this individual of G. fascicularis, increased uptake of carbon dioxide rather than increased efflux of oxygen explains the beneficial effect of water flow on photosynthesis. Rates of net photosynthesis measured in this study are among the highest ever recorded for scleractinian corals and confirm a strong scope for growth.
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Affiliation(s)
- Ronald Osinga
- Wageningen University, Aquaculture & Fisheries, PO Box 338, 6700 AH Wageningen, The Netherlands
| | - Marlous Derksen-Hooijberg
- Wageningen University, Aquaculture & Fisheries, PO Box 338, 6700 AH Wageningen, The Netherlands
- Radboud University Nijmegen, Aquatic Ecology & Environmental Biology, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Tim Wijgerde
- Wageningen University, Aquaculture & Fisheries, PO Box 338, 6700 AH Wageningen, The Netherlands
- Coralpublications, Livingstonelaan 1120, 3526 JS Utrecht, The Netherlands
| | - Johan A. J. Verreth
- Wageningen University, Aquaculture & Fisheries, PO Box 338, 6700 AH Wageningen, The Netherlands
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Wijgerde T, Silva CIF, Scherders V, van Bleijswijk J, Osinga R. Coral calcification under daily oxygen saturation and pH dynamics reveals the important role of oxygen. Biol Open 2014; 3:489-93. [PMID: 24857847 PMCID: PMC4058083 DOI: 10.1242/bio.20147922] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Coral reefs are essential to many nations, and are currently in global decline. Although climate models predict decreases in seawater pH (∼0.3 units) and oxygen saturation (∼5 percentage points), these are exceeded by the current daily pH and oxygen fluctuations on many reefs (pH 7.8-8.7 and 27-241% O2 saturation). We investigated the effect of oxygen and pH fluctuations on coral calcification in the laboratory using the model species Acropora millepora. Light calcification rates were greatly enhanced (+178%) by increased seawater pH, but only at normoxia; hyperoxia completely negated this positive effect. Dark calcification rates were significantly inhibited (51-75%) at hypoxia, whereas pH had no effect. Our preliminary results suggest that within the current oxygen and pH range, oxygen has substantial control over coral growth, whereas the role of pH is limited. This has implications for reef formation in this era of rapid climate change, which is accompanied by a decrease in seawater oxygen saturation owing to higher water temperatures and coastal eutrophication.
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Affiliation(s)
- Tim Wijgerde
- Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University, Wageningen University and Research Centre, 6709 PG Wageningen, The Netherlands
| | - Catarina I F Silva
- Biological Oceanography, Royal Netherlands Institute for Sea Research, 1797 SZ 't Horntje, The Netherlands
| | - Vera Scherders
- Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University, Wageningen University and Research Centre, 6709 PG Wageningen, The Netherlands
| | - Judith van Bleijswijk
- Biological Oceanography, Royal Netherlands Institute for Sea Research, 1797 SZ 't Horntje, The Netherlands
| | - Ronald Osinga
- Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University, Wageningen University and Research Centre, 6709 PG Wageningen, The Netherlands
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Wijgerde T, van Melis A, Silva CIF, Leal MC, Vogels L, Mutter C, Osinga R. Red light represses the photophysiology of the scleractinian coral Stylophora pistillata. PLoS One 2014; 9:e92781. [PMID: 24658108 PMCID: PMC3962463 DOI: 10.1371/journal.pone.0092781] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 02/26/2014] [Indexed: 11/19/2022] Open
Abstract
Light spectrum plays a key role in the biology of symbiotic corals, with blue light resulting in higher coral growth, zooxanthellae density, chlorophyll a content and photosynthesis rates as compared to red light. However, it is still unclear whether these physiological processes are blue-enhanced or red-repressed. This study investigated the individual and combined effects of blue and red light on the health, zooxanthellae density, photophysiology and colouration of the scleractinian coral Stylophora pistillata over 6 weeks. Coral fragments were exposed to blue, red, and combined 50/50% blue red light, at two irradiance levels (128 and 256 μmol m−2 s−1). Light spectrum affected the health/survival, zooxanthellae density, and NDVI (a proxy for chlorophyll a content) of S. pistillata. Blue light resulted in highest survival rates, whereas red light resulted in low survival at 256 μmol m−2 s−1. Blue light also resulted in higher zooxanthellae densities compared to red light at 256 μmol m−2 s−1, and a higher NDVI compared to red and combined blue red light. Overall, our results suggest that red light negatively affects the health, survival, symbiont density and NDVI of S. pistillata, with a dominance of red over blue light for NDVI.
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Affiliation(s)
- Tim Wijgerde
- Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University and Research centre, Wageningen, The Netherlands
- * E-mail:
| | - Anne van Melis
- Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University and Research centre, Wageningen, The Netherlands
| | - Catarina I. F. Silva
- Biological Oceanography, Royal Netherlands Institute for Sea Research, 't Horntje, The Netherlands
| | - Miguel C. Leal
- Departamento de Biologia & CESAM, Universidade de Aveiro, Aveiro, Portugal
- Skidaway Institute of Oceanography, University of Georgia, Savannah, Georgia, United States of America
| | - Luc Vogels
- Philips Lighting, BG Light Sources & Electronics LED Platform Development, Eindhoven, The Netherlands
| | - Claudia Mutter
- Philips Lighting, BG Light Sources & Electronics LED Platform Development, Eindhoven, The Netherlands
| | - Ronald Osinga
- Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University and Research centre, Wageningen, The Netherlands
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Wijgerde T, Jurriaans S, Hoofd M, Verreth JAJ, Osinga R. Oxygen and heterotrophy affect calcification of the scleractinian coral Galaxea fascicularis. PLoS One 2012; 7:e52702. [PMID: 23285159 PMCID: PMC3528703 DOI: 10.1371/journal.pone.0052702] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 11/20/2012] [Indexed: 11/18/2022] Open
Abstract
Heterotrophy is known to stimulate calcification of scleractinian corals, possibly through enhanced organic matrix synthesis and photosynthesis, and increased supply of metabolic DIC. In contrast to the positive long-term effects of heterotrophy, inhibition of calcification has been observed during feeding, which may be explained by a temporal oxygen limitation in coral tissue. To test this hypothesis, we measured the short-term effects of zooplankton feeding on light and dark calcification rates of the scleractinian coral Galaxea fascicularis (n = 4) at oxygen saturation levels ranging from 13 to 280%. Significant main and interactive effects of oxygen, heterotrophy and light on calcification rates were found (three-way factorial repeated measures ANOVA, p<0.05). Light and dark calcification rates of unfed corals were severely affected by hypoxia and hyperoxia, with optimal rates at 110% saturation. Light calcification rates of fed corals exhibited a similar trend, with highest rates at 150% saturation. In contrast, dark calcification rates of fed corals were close to zero under all oxygen saturations. We conclude that oxygen exerts a strong control over light and dark calcification rates of corals, and propose that in situ calcification rates are highly dynamic. Nevertheless, the inhibitory effect of heterotrophy on dark calcification appears to be oxygen-independent. We hypothesize that dark calcification is impaired during zooplankton feeding by a temporal decrease of the pH and aragonite saturation state of the calcifying medium, caused by increased respiration rates. This may invoke a transient reallocation of metabolic energy to soft tissue growth and organic matrix synthesis. These insights enhance our understanding of how oxygen and heterotrophy affect coral calcification, both in situ as well as in aquaculture.
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Affiliation(s)
- Tim Wijgerde
- Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University, Wageningen University and Research Centre, Wageningen, The Netherlands.
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Wijgerde T, Schots P, Van Onselen E, Janse M, Karruppannan E, Verreth JAJ, Osinga R. Epizoic acoelomorph flatworms impair zooplankton feeding by the scleractinian coral Galaxea fascicularis. Biol Open 2012; 2:10-7. [PMID: 23336072 PMCID: PMC3545264 DOI: 10.1242/bio.20122741] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Accepted: 09/17/2012] [Indexed: 11/20/2022] Open
Abstract
Many scleractinian coral species host epizoic acoelomorph flatworms, both in aquaculture and in situ. These symbiotic flatworms may impair coral growth and health through light-shading, mucus removal and disruption of heterotrophic feeding. To quantify the effect of epizoic flatworms on zooplankton feeding, we conducted video analyses of single polyps of Galaxea fascicularis (Linnaeus 1767) grazing on Artemia nauplii in the presence and absence of symbiotic flatworms. 18S DNA analysis revealed that flatworms inhabiting G. fascicularis belonged to the genus Waminoa (Convolutidae), which were hosted at a density of 3.6±0.4 individuals polyp−1. Polyps hosting flatworms exhibited prey capture rates of 2.2±2.5, 3.4±4.5 and 2.7±3.4 nauplii polyp−1 30 min−1 at prey concentrations of 250, 500 and 1,000 nauplii L−1, respectively. Polyps that had their flatworms removed displayed prey capture rates of 2.7±1.6, 4.8±4.1 and 16.9±10.3 nauplii polyp−1 30 min−1. Significant main and interactive effects of flatworm presence and ambient prey concentration were found, reflected by the fact that flatworms significantly impaired host feeding rates at the highest prey density of 1,000 nauplii L−1. In addition, flatworms displayed kleptoparasitism, removing between 0.1±0.3 and 0.6±1.1 nauplii 30 min−1 from the oral disc of their host, or 5.3±3.3 to 50.0±2.1% of prey acquired by the coral. We suggest classifying the coral-associated Waminoa sp. as an epizoic parasite, as its presence may negatively affect growth and health of the host.
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Affiliation(s)
- Tim Wijgerde
- Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University and Research Centre , 6709 PG Wageningen , The Netherlands
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Haugen T, Almeida FFL, Andersson E, Bogerd J, Male R, Skaar KS, Schulz RW, Sørhus E, Wijgerde T, Taranger GL. Sex differentiation in Atlantic cod (Gadus morhua L.): morphological and gene expression studies. Reprod Biol Endocrinol 2012; 10:47. [PMID: 22709434 PMCID: PMC3433390 DOI: 10.1186/1477-7827-10-47] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 06/18/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In differentiated gonochoristic species, a bipotential gonad develops into an ovary or testis during sex differentiation. Knowledge about this process is necessary to improve methods for masculinizing genetically female Atlantic cod for the subsequent purpose of producing all-female populations. METHODS Gonads were examined histologically in juveniles from 14 to 39 mm total body length (TL). Number and size of germ cells were determined in a subset of the samples. Relevant genes were cloned, and mRNA levels determined by qPCR of amh, cyp19a1a; dax1 (nr0b2); shp (nr0b2a) and sox9b in a mixed-sex and an all-female population ranging from 12-49 mm TL. RESULTS Individuals between 14-20 mm TL could be separated in two subgroups based on gonad size and germ cell number. Ovarian cavity formation was observed in some individuals from 18-20 mm TL. The mixed sex population displayed bimodal expression patterns as regards cyp19a1a (starting at 12 mm TL) and amh (starting at 20 mm TL) mRNA levels. After approximately 30 mm TL, cyp19a1a and amh displayed a gradual increase in both sexes. No apparent, sex-dependent expression patterns were found for dax1, shp or sox9b transcripts. However, shp levels were high until the larvae reached around 35 mm TL and then dropped to low levels, while dax1 remained low until 35 mm TL, and then increased sharply. CONCLUSIONS The morphological sex differentiation in females commenced between 14-20 mm TL, and ovarian cavities were evident by 18-20 mm TL. Testis development occurred later, and was morphologically evident after 30 mm TL. This pattern was corroborated with sexually dimorphic expression patterns of cyp19a1a from 12-13 mm TL, and a male-specific increase in amh from 20 mm TL.
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Affiliation(s)
- Trine Haugen
- Institute of Marine Research, Nordnes, P.O. Box 1870, N-5817, Bergen, Norway
| | - Fernanda FL Almeida
- Utrecht University, Science Faculty, Department of Biology, Padualaan 8, NL-3584 CH, Utrecht, The Netherlands
- Embrapa Western Amazon, Rodovia AM-10, Km 29, PO Box 319, Manaus, AM-Brazil-69010-970, Brazil
| | - Eva Andersson
- Institute of Marine Research, Nordnes, P.O. Box 1870, N-5817, Bergen, Norway
| | - Jan Bogerd
- Utrecht University, Science Faculty, Department of Biology, Padualaan 8, NL-3584 CH, Utrecht, The Netherlands
| | - Rune Male
- University of Bergen, Department of Molecular Biology, HiB, Thormøllensgt. 55, N-5020, Bergen, Norway
| | - Katrine S Skaar
- University of Bergen, Department of Molecular Biology, HiB, Thormøllensgt. 55, N-5020, Bergen, Norway
| | - Rüdiger W Schulz
- Utrecht University, Science Faculty, Department of Biology, Padualaan 8, NL-3584 CH, Utrecht, The Netherlands
| | - Elin Sørhus
- Institute of Marine Research, Nordnes, P.O. Box 1870, N-5817, Bergen, Norway
| | - Tim Wijgerde
- Utrecht University, Science Faculty, Department of Biology, Padualaan 8, NL-3584 CH, Utrecht, The Netherlands
| | - Geir L Taranger
- Institute of Marine Research, Nordnes, P.O. Box 1870, N-5817, Bergen, Norway
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Wijgerde T, Diantari R, Lewaru MW, Verreth JAJ, Osinga R. Extracoelenteric zooplankton feeding is a key mechanism of nutrient acquisition for the scleractinian coral Galaxea fascicularis. J Exp Biol 2011; 214:3351-7. [DOI: 10.1242/jeb.058354] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Internal and external feeding on zooplankton may provide scleractinian corals with important nutrients. However, the latter process has never been properly quantified. To quantify the dynamics of zooplankton capture, digestion and release for a scleractinian coral, we performed detailed video analyses of Galaxea fascicularis feeding on Artemia nauplii. A highly dynamic process of prey capture, digestion and release was observed. A single G. fascicularis polyp (N=3) captured 558±67 and released 383±75 Artemia nauplii over a 6 h interval. On average, 98.6% of prey captured was not ingested. Instead, prey items were clustered into aggregates that were digested externally by mesenterial filaments. In addition, we employed carbon, nitrogen and phosphorus analysis of zooplankton before and after digestion by G. fascicularis colonies (N=6). For total organic carbon, 43.1% (0.298±0.148 μg Artemia–1) was lost after 6 h of digestion. For total organic nitrogen, total organic phosphorus and orthophosphate (PO43–), these values were 51.3% (0.059±0.028 μg Artemia–1), 50.9% (0.009±0.004 μg Artemia–1) and 84.6% (0.0019±0.0008 μg Artemia–1), respectively. For extracoelenteric zooplankton feeding alone, total estimated nutrient inputs for G. fascicularis colonies were 76.5±0.0 μg organic carbon, 15.2±0.0 μg organic nitrogen, 2.3±0.2 μg organic phosphorus and 0.5±0.8 μg inorganic phosphorus per cm2 coral tissue per day. These values exceed calculations based on intracoelenteric feeding by up to two orders of magnitude. Our results demonstrate that extracoelenteric zooplankton feeding is a key mechanism of nutrient acquisition for a scleractinian coral. These results are of importance to coral aquaculture and our understanding of benthic–pelagic coupling on coral reefs.
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Affiliation(s)
- Tim Wijgerde
- Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University, Wageningen University and Research centre, 6709 PG Wageningen, The Netherlands
| | - Rara Diantari
- Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University, Wageningen University and Research centre, 6709 PG Wageningen, The Netherlands
| | - Muhammad Wahyudin Lewaru
- Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University, Wageningen University and Research centre, 6709 PG Wageningen, The Netherlands
| | - Johan A. J. Verreth
- Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University, Wageningen University and Research centre, 6709 PG Wageningen, The Netherlands
| | - Ronald Osinga
- Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University, Wageningen University and Research centre, 6709 PG Wageningen, The Netherlands
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