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Sten I. Siikavuopio - One of the best experts on this subject based on the ideXlab platform.
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Effects of body weight and temperature on feed intake, gonad growth and oxygen consumption in Green Sea urchin, Strongylocentrotus droebachiensis
Aquaculture, 2008Co-Authors: Sten I. Siikavuopio, Atle Mortensen, Jørgen S. ChristiansenAbstract:Abstract The current study describes the metabolic performance of adult Green Sea urchin Strongylocentrotus droebachiensis in terms of oxygen consumption, feed intake and gonad growth in relation to body weight and temperature. The experiments were conducted at six constant temperatures (4, 6, 8, 10, 12 and 14 °C), and with three body size groups, i.e. small (S, 40 g), medium (M, 65 g), and large (L, 100 g). Results show that 10–12 °C is the optimum temperature for gonad growth for 40–100-g Green Sea urchin during summer/autumn, and that there is an inverse relationship between optimum temperature and size. Contrary to gonad growth, both feed intake and oxygen consumption continued to increase throughout the entire temperature range (4–14 °C). The Q10 values for oxygen consumption of fed animals were in the normal range (1.72–3.01), while the corresponding values for starved animals were low (1.17–1.36), indicating negligible effects of temperature on aerobic metabolism during starvation. The energetic analyses indicate a poorly developed regulation of energy intake in relation to energy expenditure. The oxygen consumption data from this study can, together with a still missing description of the relationship between oxygen saturation and somatic and gonad growth, be used to evaluate the water requirement of Green Sea urchin in aquaculture.
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Effects of carbon dioxide exposure on feed intake and gonad growth in Green Sea urchin, Strongylocentrotus droebachiensis
Aquaculture, 2007Co-Authors: Sten I. Siikavuopio, Trine Dale, Atle Mortensen, Atle FossAbstract:Abstract The effects of carbon dioxide (CO 2(aq) ) on gonad growth and feed intake in Green Sea urchin, Strongylocentrotus droebachiensis , were examined. Adult Sea urchins with a mean (S.D.) live weight of 50.0 (11.2) g were exposed to two levels of carbon dioxide (CO 2(aq) ), (1.1 (control) and 18.1 mg l − 1 ), for 56 days at 6.0 °C and 33‰. Gonad growth was significantly reduced in the high CO 2 concentration group compared to the control group. In the high carbon dioxide treatment, gonad growth was 67% less than the control treatment. Weekly feed intake and total feed consumption were significantly reduced in the high concentration group. The reduction in gonad growth was attributed to a decrease in feed intake and impaired feed conversion efficiency. The present study demonstrates that adult Green Sea urchins show low tolerance to increased carbon dioxide levels, and are unable to maintain high gonad growth facing such conditions.
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Effects of hypoxia on feed intake and gonad growth in the Green Sea urchin, Strongylocentrotus droebachiensis
Aquaculture, 2007Co-Authors: Sten I. Siikavuopio, Trine Dale, Atle Mortensen, Atle FossAbstract:Abstract The effects of oxygen content on gonad growth and feed intake in “Green Sea urchin”, Strongylocentrotus droebachiensis, were examined. Adult Sea urchins with a mean (S.D.) live weight of 51.0 (12.2) g were reared at oxygen levels of 4.0, 6.0 (hypoxia) and 9.5 mg l− 1 (normoxia), for 54 days at 8.0 °C and 33‰. Gonad growth and total food consumption were significantly higher in the control group (normoxia) compared with the hypoxic groups at the end of the experiment. Weekly feed intake and total feed consumption were significantly reduced in the two hypoxic groups. The reduction in gonad growth was attributed to a decrease in feed intake and impaired food conversion efficiency. Overall, our findings suggest that adult Green Sea urchins show low tolerance to hypoxia, and are unable to maintain high gonad growth facing such conditions.
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effects of temperature and Season on gonad growth and feed intake in the Green Sea urchin strongylocentrotus droebachiensis
Aquaculture, 2006Co-Authors: Sten I. Siikavuopio, J S Christianse, Trine DaleAbstract:Abstract The effects of water temperature and Season on feed intake and gonad growth of Green Sea urchin Strongylocentrotus droebachiensis were evaluated. Animals were tested at six temperatures (4, 6, 8, 10, 12, and 14 °C) in summer (July–September) and in winter (November–January). Sea urchins (64.5 ± 3.4 g mean wet body weight ± S.D.) were held individually in square chambers and fed ad libitum a formulated moist feed. Gonad index (GI), feed intake (FI), and feed conversion ratios (FCR) were measured. There was a significant increase in GI for all treatments during the summer trial, and Sea urchins held at 6 °C had a significantly larger GI compared to those held at 4 °C ( P There was a significant and linear increase in FI with increasing temperature both during summer and winter. Thus, FI in the summer (S) and winter (W) trials increased from initial 0.34 (S) and 0.26 (W) (g/urchin per day) at 4 °C, to 0.71 (S) and 0.93 (W) (g/urchin per day) at 14 °C. In summer, Sea urchins held at 12 °C had a significantly lower FCR (3.3) compared to animals held at 8 °C (FCR = 4.0). The situation was reversed in winter, where Sea urchins displayed the lower FCR (3.7) at 8 °C than those held at 12 °C (FCR = 6.0). Overall, our findings suggest that optimum gonad growth of adult Green Sea urchins is achieved at higher temperatures in summer than in winter.
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Effects of temperature and Season on gonad growth and feed intake in the Green Sea urchin (Strongylocentrotus droebachiensis)
Aquaculture, 2006Co-Authors: Sten I. Siikavuopio, Jørgen S. Christiansen, Trine DaleAbstract:Papers number 1, 2, 3, 5, 6, 7, 8, 9 and 10 of the thesis are not available in Munin due to publishers' restrictions: 1. Siikavuopio, S. I., Mortensen. A., Christiansen, J. S.: "Effects of body weight and temperature on feeding, gonad growth and oxygen consumption in Green Sea urchin, Strongylocentrotus droebachiensis." Aquaculture 2008; 281, 77-82 (Elsevier). Available at http://dx.doi.org/http://dx.doi.org/10.1016j.aquaculture.2008.05.033>2. Siikavuopio, S. I., Christiansen, J.S., Dale, T.: "Effects of temperature and Season on gonad growth and feed intake in the Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2006; 255, 389-394 (Elsevier). Available at http://dx.doi.org/http://dx.doi.org10.1016j.aquaculture.2005.12.0213. Siikavuopio, S. I., Christiansen, J. S., Sæther, B-S., Dale, T.: "Seasonal variation in feed intake under constant temperature and natural photoperiod in the Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2006; 272, 328-334 (Elsevier). Available at http://dx.doi.org/http://dx.doi.org/10.1016/j.aquaculture.2007.09.0035. Siikavuopio, S. I., Dale, T., Foss, A., Mortensen, A.: "Effects of chronic ammonia exposure on gonad growth and survival in Green Sea urchin, Strongylocentrotus droebachiensis." Aquaculture 2004; 242, 313-320 (Elsevier). Available at http://dx.doi.org/10.1016j.aquaculture.2004.08.0426. Siikavuopio, S. I., Dale, T., Christiansen, J. S., Nevermo, I.: " Effects of chronic nitrite exposure on gonad growth in Green Sea urchin, Strongylocentrotus droebachiensis." Aquaculture 2004; 242, 357-363 (Elsevier). Available at http://dx.doi.org/10.1016/j.aquaculture.2004.09.0077. Siikavuopio, S. I., Dale, T., Mortensen, A., Foss, A.: " Effects of hypoxia on feed intake and gonad growth in the Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2007; 266, 112-116 (Elsevier). Available at http://dx.doi.org/10.1016j.aquaculture.2007.02.0288. Siikavuopio, S. I., Mortensen, A., Dale, T., Foss, A.: " Effects of carbon dioxide exposure on feed intake and gonad growth in Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2007; 266, 97-101 (Elsevier).Available at http://dx.doi.org/10.1016/j.aquaculture.2007.02.0449. Siikavuopio, S. I., Dale, T., Mortensen, A.: " The effects of stocking density on gonad growth, survival and feed intake of adult Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2007; 262, 78-85 (Elsevier). Available at http://dx.doi.org/10.1016/j.aquaculture.2006.09.04510. Christiansen, J. S., Siikavuopio, S. I.: "The relationship between feed intake and gonad growth of single and stocked Green Sea urchin (Strongylocentrotus droebachiensis) in a raceway culture." Aquaculture 2007; 262, 163-167 (Elsevier). Available at http://dx.doi.org/10.1016/j.aquaculture.2006.09.043Ved hjelp av eksperimentelle studier har en undersøkt effekten av ulike miljøfaktorer på gonadevekst hos Drøbak-kråkebolle i oppdrett. Dette inkluderer effekten av temperatur, størrelse, sesong, individtetthet og forskjellige vannkvalitetsparametre (O2, CO2, nitritt, ammoniakk) og håndtering på overlevelse, gonadevekst, fôrinntak og fôrutnyttelse. Optimal temperatur for gonadevekst hos voksne kråkeboller ligger mellom 10 og 12 ºC om sommeren og ca 8 ºC om vinteren. Temperaturer over 12 ºC gir redusert vekst og fôrutnyttelse. Studiene viser at Drøbak-kråkebollen har lav toleranse for CO2, nitritt og ammoniakk sammenliknet med laksefisk. Forhøyede nivåer av disse stoffene medfører redusert gonadevekst, mens fôrinntaket blir lite påvirket. Dette resulterer i svært dårlig fôrutnyttelse. Kråkebollene har lavt oksygenforbruk, men er likevel svært følsomme for reduksjoner i vannets oksygeninnhold. Disse forholdene tilsier at kråkeboller i oppdrett krever stor vannutskifting for å opprettholde maksimal gonadevekst. For høy individtetthet i oppdrett medfører også nedsatt gonadevekst. Arbeidet omfatter en kartlegging av akseptabel tetthet for kråkebolle i oppdrett
Trine Dale - One of the best experts on this subject based on the ideXlab platform.
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Effects of carbon dioxide exposure on feed intake and gonad growth in Green Sea urchin, Strongylocentrotus droebachiensis
Aquaculture, 2007Co-Authors: Sten I. Siikavuopio, Trine Dale, Atle Mortensen, Atle FossAbstract:Abstract The effects of carbon dioxide (CO 2(aq) ) on gonad growth and feed intake in Green Sea urchin, Strongylocentrotus droebachiensis , were examined. Adult Sea urchins with a mean (S.D.) live weight of 50.0 (11.2) g were exposed to two levels of carbon dioxide (CO 2(aq) ), (1.1 (control) and 18.1 mg l − 1 ), for 56 days at 6.0 °C and 33‰. Gonad growth was significantly reduced in the high CO 2 concentration group compared to the control group. In the high carbon dioxide treatment, gonad growth was 67% less than the control treatment. Weekly feed intake and total feed consumption were significantly reduced in the high concentration group. The reduction in gonad growth was attributed to a decrease in feed intake and impaired feed conversion efficiency. The present study demonstrates that adult Green Sea urchins show low tolerance to increased carbon dioxide levels, and are unable to maintain high gonad growth facing such conditions.
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Effects of hypoxia on feed intake and gonad growth in the Green Sea urchin, Strongylocentrotus droebachiensis
Aquaculture, 2007Co-Authors: Sten I. Siikavuopio, Trine Dale, Atle Mortensen, Atle FossAbstract:Abstract The effects of oxygen content on gonad growth and feed intake in “Green Sea urchin”, Strongylocentrotus droebachiensis, were examined. Adult Sea urchins with a mean (S.D.) live weight of 51.0 (12.2) g were reared at oxygen levels of 4.0, 6.0 (hypoxia) and 9.5 mg l− 1 (normoxia), for 54 days at 8.0 °C and 33‰. Gonad growth and total food consumption were significantly higher in the control group (normoxia) compared with the hypoxic groups at the end of the experiment. Weekly feed intake and total feed consumption were significantly reduced in the two hypoxic groups. The reduction in gonad growth was attributed to a decrease in feed intake and impaired food conversion efficiency. Overall, our findings suggest that adult Green Sea urchins show low tolerance to hypoxia, and are unable to maintain high gonad growth facing such conditions.
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effects of temperature and Season on gonad growth and feed intake in the Green Sea urchin strongylocentrotus droebachiensis
Aquaculture, 2006Co-Authors: Sten I. Siikavuopio, J S Christianse, Trine DaleAbstract:Abstract The effects of water temperature and Season on feed intake and gonad growth of Green Sea urchin Strongylocentrotus droebachiensis were evaluated. Animals were tested at six temperatures (4, 6, 8, 10, 12, and 14 °C) in summer (July–September) and in winter (November–January). Sea urchins (64.5 ± 3.4 g mean wet body weight ± S.D.) were held individually in square chambers and fed ad libitum a formulated moist feed. Gonad index (GI), feed intake (FI), and feed conversion ratios (FCR) were measured. There was a significant increase in GI for all treatments during the summer trial, and Sea urchins held at 6 °C had a significantly larger GI compared to those held at 4 °C ( P There was a significant and linear increase in FI with increasing temperature both during summer and winter. Thus, FI in the summer (S) and winter (W) trials increased from initial 0.34 (S) and 0.26 (W) (g/urchin per day) at 4 °C, to 0.71 (S) and 0.93 (W) (g/urchin per day) at 14 °C. In summer, Sea urchins held at 12 °C had a significantly lower FCR (3.3) compared to animals held at 8 °C (FCR = 4.0). The situation was reversed in winter, where Sea urchins displayed the lower FCR (3.7) at 8 °C than those held at 12 °C (FCR = 6.0). Overall, our findings suggest that optimum gonad growth of adult Green Sea urchins is achieved at higher temperatures in summer than in winter.
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Effects of temperature and Season on gonad growth and feed intake in the Green Sea urchin (Strongylocentrotus droebachiensis)
Aquaculture, 2006Co-Authors: Sten I. Siikavuopio, Jørgen S. Christiansen, Trine DaleAbstract:Papers number 1, 2, 3, 5, 6, 7, 8, 9 and 10 of the thesis are not available in Munin due to publishers' restrictions: 1. Siikavuopio, S. I., Mortensen. A., Christiansen, J. S.: "Effects of body weight and temperature on feeding, gonad growth and oxygen consumption in Green Sea urchin, Strongylocentrotus droebachiensis." Aquaculture 2008; 281, 77-82 (Elsevier). Available at http://dx.doi.org/http://dx.doi.org/10.1016j.aquaculture.2008.05.033>2. Siikavuopio, S. I., Christiansen, J.S., Dale, T.: "Effects of temperature and Season on gonad growth and feed intake in the Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2006; 255, 389-394 (Elsevier). Available at http://dx.doi.org/http://dx.doi.org10.1016j.aquaculture.2005.12.0213. Siikavuopio, S. I., Christiansen, J. S., Sæther, B-S., Dale, T.: "Seasonal variation in feed intake under constant temperature and natural photoperiod in the Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2006; 272, 328-334 (Elsevier). Available at http://dx.doi.org/http://dx.doi.org/10.1016/j.aquaculture.2007.09.0035. Siikavuopio, S. I., Dale, T., Foss, A., Mortensen, A.: "Effects of chronic ammonia exposure on gonad growth and survival in Green Sea urchin, Strongylocentrotus droebachiensis." Aquaculture 2004; 242, 313-320 (Elsevier). Available at http://dx.doi.org/10.1016j.aquaculture.2004.08.0426. Siikavuopio, S. I., Dale, T., Christiansen, J. S., Nevermo, I.: " Effects of chronic nitrite exposure on gonad growth in Green Sea urchin, Strongylocentrotus droebachiensis." Aquaculture 2004; 242, 357-363 (Elsevier). Available at http://dx.doi.org/10.1016/j.aquaculture.2004.09.0077. Siikavuopio, S. I., Dale, T., Mortensen, A., Foss, A.: " Effects of hypoxia on feed intake and gonad growth in the Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2007; 266, 112-116 (Elsevier). Available at http://dx.doi.org/10.1016j.aquaculture.2007.02.0288. Siikavuopio, S. I., Mortensen, A., Dale, T., Foss, A.: " Effects of carbon dioxide exposure on feed intake and gonad growth in Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2007; 266, 97-101 (Elsevier).Available at http://dx.doi.org/10.1016/j.aquaculture.2007.02.0449. Siikavuopio, S. I., Dale, T., Mortensen, A.: " The effects of stocking density on gonad growth, survival and feed intake of adult Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2007; 262, 78-85 (Elsevier). Available at http://dx.doi.org/10.1016/j.aquaculture.2006.09.04510. Christiansen, J. S., Siikavuopio, S. I.: "The relationship between feed intake and gonad growth of single and stocked Green Sea urchin (Strongylocentrotus droebachiensis) in a raceway culture." Aquaculture 2007; 262, 163-167 (Elsevier). Available at http://dx.doi.org/10.1016/j.aquaculture.2006.09.043Ved hjelp av eksperimentelle studier har en undersøkt effekten av ulike miljøfaktorer på gonadevekst hos Drøbak-kråkebolle i oppdrett. Dette inkluderer effekten av temperatur, størrelse, sesong, individtetthet og forskjellige vannkvalitetsparametre (O2, CO2, nitritt, ammoniakk) og håndtering på overlevelse, gonadevekst, fôrinntak og fôrutnyttelse. Optimal temperatur for gonadevekst hos voksne kråkeboller ligger mellom 10 og 12 ºC om sommeren og ca 8 ºC om vinteren. Temperaturer over 12 ºC gir redusert vekst og fôrutnyttelse. Studiene viser at Drøbak-kråkebollen har lav toleranse for CO2, nitritt og ammoniakk sammenliknet med laksefisk. Forhøyede nivåer av disse stoffene medfører redusert gonadevekst, mens fôrinntaket blir lite påvirket. Dette resulterer i svært dårlig fôrutnyttelse. Kråkebollene har lavt oksygenforbruk, men er likevel svært følsomme for reduksjoner i vannets oksygeninnhold. Disse forholdene tilsier at kråkeboller i oppdrett krever stor vannutskifting for å opprettholde maksimal gonadevekst. For høy individtetthet i oppdrett medfører også nedsatt gonadevekst. Arbeidet omfatter en kartlegging av akseptabel tetthet for kråkebolle i oppdrett
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Effects of chronic ammonia exposure on gonad growth and survival in Green Sea urchin Strongylocentrotus droebachiensis
Aquaculture, 2004Co-Authors: Sten I. Siikavuopio, Trine Dale, Atle Foss, Atle MortensenAbstract:Abstract The effects of chronic unionised ammonia (UIA) exposure on mortality, gonad growth and feed intake (FC) in Green Sea urchin Strongylocentrotus droebachiensis were examined. Sea urchins with a mean (S.D.) initial weight of 58.2 (15.2) g were reared in shallow raceways (initial stocking density of 1.9 kg m −2 ) and exposed to four concentrations of UIA [0.0001 (control), 0.016 (low), 0.032 (medium) and 0.068 (high) mg l −1 ] for 42 days at 7.3 °C, salinity 33‰ and pH 8.04. Sea urchin mortality was influenced by UIA concentrations and increased with increasing levels of UIA. The mortality in the high-concentration group increased throughout the experimental period, and, ultimately, only 24% of the Sea urchins survived. Compared to the control, gonad growth was significantly reduced at UIA concentrations above 0.016 mg l −1 . Sea urchins from the exposed groups did not display a significant reduction in feed intake compared to the control, which suggests that the gonad growth reduction could not be attributed to a decreased feed intake. The present study demonstrates that adult Green Sea urchins show low tolerance to ambient unionised ammonia and are unable to maintain high gonad growth facing such conditions.
Jane Budd - One of the best experts on this subject based on the ideXlab platform.
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Marine debris ingestion of Green Sea turtles, Chelonia mydas, (Linnaeus, 1758) from the eastern coast of the United Arab Emirates
Marine Pollution Bulletin, 2018Co-Authors: Fadi Yaghmour, Marwa Al Bousi, Brendan Whittington-jones, John Pereira, Soledad García-nuñez, Jane BuddAbstract:Abstract The deleterious effects of marine debris ingestion on marine turtles are well documented in literature globally. In this study, the qualitative and quantitative aspects of marine debris ingested by 14 stranded Green Sea turtles Chelonia mydas, (Linnaeus, 1758) along the eastern coast of the United Arab Emirates were investigated. The numeric and gravimetric proportions of debris in the esophagus, stomach and intestines were documented following classification of color, presumed sources and Marine Strategy Framework Directive categories and sub-categories. The results show that 85.7% of the specimens examined consumed marine debris. On average, specimens consumed 61.9 ± 17.2 items of 1.0 ± 0.3 g mass. Plastics, particularly white, and transparent thread-like and sheet-like plastics, were the predominant debris ingested. The results reflect a potentially high level of interaction between Green Sea turtles and anthropogenic marine debris along the Gulf of Oman coast of the UAE.
Atle Mortensen - One of the best experts on this subject based on the ideXlab platform.
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Effects of body weight and temperature on feed intake, gonad growth and oxygen consumption in Green Sea urchin, Strongylocentrotus droebachiensis
Aquaculture, 2008Co-Authors: Sten I. Siikavuopio, Atle Mortensen, Jørgen S. ChristiansenAbstract:Abstract The current study describes the metabolic performance of adult Green Sea urchin Strongylocentrotus droebachiensis in terms of oxygen consumption, feed intake and gonad growth in relation to body weight and temperature. The experiments were conducted at six constant temperatures (4, 6, 8, 10, 12 and 14 °C), and with three body size groups, i.e. small (S, 40 g), medium (M, 65 g), and large (L, 100 g). Results show that 10–12 °C is the optimum temperature for gonad growth for 40–100-g Green Sea urchin during summer/autumn, and that there is an inverse relationship between optimum temperature and size. Contrary to gonad growth, both feed intake and oxygen consumption continued to increase throughout the entire temperature range (4–14 °C). The Q10 values for oxygen consumption of fed animals were in the normal range (1.72–3.01), while the corresponding values for starved animals were low (1.17–1.36), indicating negligible effects of temperature on aerobic metabolism during starvation. The energetic analyses indicate a poorly developed regulation of energy intake in relation to energy expenditure. The oxygen consumption data from this study can, together with a still missing description of the relationship between oxygen saturation and somatic and gonad growth, be used to evaluate the water requirement of Green Sea urchin in aquaculture.
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Effects of carbon dioxide exposure on feed intake and gonad growth in Green Sea urchin, Strongylocentrotus droebachiensis
Aquaculture, 2007Co-Authors: Sten I. Siikavuopio, Trine Dale, Atle Mortensen, Atle FossAbstract:Abstract The effects of carbon dioxide (CO 2(aq) ) on gonad growth and feed intake in Green Sea urchin, Strongylocentrotus droebachiensis , were examined. Adult Sea urchins with a mean (S.D.) live weight of 50.0 (11.2) g were exposed to two levels of carbon dioxide (CO 2(aq) ), (1.1 (control) and 18.1 mg l − 1 ), for 56 days at 6.0 °C and 33‰. Gonad growth was significantly reduced in the high CO 2 concentration group compared to the control group. In the high carbon dioxide treatment, gonad growth was 67% less than the control treatment. Weekly feed intake and total feed consumption were significantly reduced in the high concentration group. The reduction in gonad growth was attributed to a decrease in feed intake and impaired feed conversion efficiency. The present study demonstrates that adult Green Sea urchins show low tolerance to increased carbon dioxide levels, and are unable to maintain high gonad growth facing such conditions.
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Effects of hypoxia on feed intake and gonad growth in the Green Sea urchin, Strongylocentrotus droebachiensis
Aquaculture, 2007Co-Authors: Sten I. Siikavuopio, Trine Dale, Atle Mortensen, Atle FossAbstract:Abstract The effects of oxygen content on gonad growth and feed intake in “Green Sea urchin”, Strongylocentrotus droebachiensis, were examined. Adult Sea urchins with a mean (S.D.) live weight of 51.0 (12.2) g were reared at oxygen levels of 4.0, 6.0 (hypoxia) and 9.5 mg l− 1 (normoxia), for 54 days at 8.0 °C and 33‰. Gonad growth and total food consumption were significantly higher in the control group (normoxia) compared with the hypoxic groups at the end of the experiment. Weekly feed intake and total feed consumption were significantly reduced in the two hypoxic groups. The reduction in gonad growth was attributed to a decrease in feed intake and impaired food conversion efficiency. Overall, our findings suggest that adult Green Sea urchins show low tolerance to hypoxia, and are unable to maintain high gonad growth facing such conditions.
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Effects of chronic ammonia exposure on gonad growth and survival in Green Sea urchin Strongylocentrotus droebachiensis
Aquaculture, 2004Co-Authors: Sten I. Siikavuopio, Trine Dale, Atle Foss, Atle MortensenAbstract:Abstract The effects of chronic unionised ammonia (UIA) exposure on mortality, gonad growth and feed intake (FC) in Green Sea urchin Strongylocentrotus droebachiensis were examined. Sea urchins with a mean (S.D.) initial weight of 58.2 (15.2) g were reared in shallow raceways (initial stocking density of 1.9 kg m −2 ) and exposed to four concentrations of UIA [0.0001 (control), 0.016 (low), 0.032 (medium) and 0.068 (high) mg l −1 ] for 42 days at 7.3 °C, salinity 33‰ and pH 8.04. Sea urchin mortality was influenced by UIA concentrations and increased with increasing levels of UIA. The mortality in the high-concentration group increased throughout the experimental period, and, ultimately, only 24% of the Sea urchins survived. Compared to the control, gonad growth was significantly reduced at UIA concentrations above 0.016 mg l −1 . Sea urchins from the exposed groups did not display a significant reduction in feed intake compared to the control, which suggests that the gonad growth reduction could not be attributed to a decreased feed intake. The present study demonstrates that adult Green Sea urchins show low tolerance to ambient unionised ammonia and are unable to maintain high gonad growth facing such conditions.
Jørgen S. Christiansen - One of the best experts on this subject based on the ideXlab platform.
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Effects of body weight and temperature on feed intake, gonad growth and oxygen consumption in Green Sea urchin, Strongylocentrotus droebachiensis
Aquaculture, 2008Co-Authors: Sten I. Siikavuopio, Atle Mortensen, Jørgen S. ChristiansenAbstract:Abstract The current study describes the metabolic performance of adult Green Sea urchin Strongylocentrotus droebachiensis in terms of oxygen consumption, feed intake and gonad growth in relation to body weight and temperature. The experiments were conducted at six constant temperatures (4, 6, 8, 10, 12 and 14 °C), and with three body size groups, i.e. small (S, 40 g), medium (M, 65 g), and large (L, 100 g). Results show that 10–12 °C is the optimum temperature for gonad growth for 40–100-g Green Sea urchin during summer/autumn, and that there is an inverse relationship between optimum temperature and size. Contrary to gonad growth, both feed intake and oxygen consumption continued to increase throughout the entire temperature range (4–14 °C). The Q10 values for oxygen consumption of fed animals were in the normal range (1.72–3.01), while the corresponding values for starved animals were low (1.17–1.36), indicating negligible effects of temperature on aerobic metabolism during starvation. The energetic analyses indicate a poorly developed regulation of energy intake in relation to energy expenditure. The oxygen consumption data from this study can, together with a still missing description of the relationship between oxygen saturation and somatic and gonad growth, be used to evaluate the water requirement of Green Sea urchin in aquaculture.
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Effects of temperature and Season on gonad growth and feed intake in the Green Sea urchin (Strongylocentrotus droebachiensis)
Aquaculture, 2006Co-Authors: Sten I. Siikavuopio, Jørgen S. Christiansen, Trine DaleAbstract:Papers number 1, 2, 3, 5, 6, 7, 8, 9 and 10 of the thesis are not available in Munin due to publishers' restrictions: 1. Siikavuopio, S. I., Mortensen. A., Christiansen, J. S.: "Effects of body weight and temperature on feeding, gonad growth and oxygen consumption in Green Sea urchin, Strongylocentrotus droebachiensis." Aquaculture 2008; 281, 77-82 (Elsevier). Available at http://dx.doi.org/http://dx.doi.org/10.1016j.aquaculture.2008.05.033>2. Siikavuopio, S. I., Christiansen, J.S., Dale, T.: "Effects of temperature and Season on gonad growth and feed intake in the Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2006; 255, 389-394 (Elsevier). Available at http://dx.doi.org/http://dx.doi.org10.1016j.aquaculture.2005.12.0213. Siikavuopio, S. I., Christiansen, J. S., Sæther, B-S., Dale, T.: "Seasonal variation in feed intake under constant temperature and natural photoperiod in the Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2006; 272, 328-334 (Elsevier). Available at http://dx.doi.org/http://dx.doi.org/10.1016/j.aquaculture.2007.09.0035. Siikavuopio, S. I., Dale, T., Foss, A., Mortensen, A.: "Effects of chronic ammonia exposure on gonad growth and survival in Green Sea urchin, Strongylocentrotus droebachiensis." Aquaculture 2004; 242, 313-320 (Elsevier). Available at http://dx.doi.org/10.1016j.aquaculture.2004.08.0426. Siikavuopio, S. I., Dale, T., Christiansen, J. S., Nevermo, I.: " Effects of chronic nitrite exposure on gonad growth in Green Sea urchin, Strongylocentrotus droebachiensis." Aquaculture 2004; 242, 357-363 (Elsevier). Available at http://dx.doi.org/10.1016/j.aquaculture.2004.09.0077. Siikavuopio, S. I., Dale, T., Mortensen, A., Foss, A.: " Effects of hypoxia on feed intake and gonad growth in the Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2007; 266, 112-116 (Elsevier). Available at http://dx.doi.org/10.1016j.aquaculture.2007.02.0288. Siikavuopio, S. I., Mortensen, A., Dale, T., Foss, A.: " Effects of carbon dioxide exposure on feed intake and gonad growth in Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2007; 266, 97-101 (Elsevier).Available at http://dx.doi.org/10.1016/j.aquaculture.2007.02.0449. Siikavuopio, S. I., Dale, T., Mortensen, A.: " The effects of stocking density on gonad growth, survival and feed intake of adult Green Sea urchin (Strongylocentrotus droebachiensis)." Aquaculture 2007; 262, 78-85 (Elsevier). Available at http://dx.doi.org/10.1016/j.aquaculture.2006.09.04510. Christiansen, J. S., Siikavuopio, S. I.: "The relationship between feed intake and gonad growth of single and stocked Green Sea urchin (Strongylocentrotus droebachiensis) in a raceway culture." Aquaculture 2007; 262, 163-167 (Elsevier). Available at http://dx.doi.org/10.1016/j.aquaculture.2006.09.043Ved hjelp av eksperimentelle studier har en undersøkt effekten av ulike miljøfaktorer på gonadevekst hos Drøbak-kråkebolle i oppdrett. Dette inkluderer effekten av temperatur, størrelse, sesong, individtetthet og forskjellige vannkvalitetsparametre (O2, CO2, nitritt, ammoniakk) og håndtering på overlevelse, gonadevekst, fôrinntak og fôrutnyttelse. Optimal temperatur for gonadevekst hos voksne kråkeboller ligger mellom 10 og 12 ºC om sommeren og ca 8 ºC om vinteren. Temperaturer over 12 ºC gir redusert vekst og fôrutnyttelse. Studiene viser at Drøbak-kråkebollen har lav toleranse for CO2, nitritt og ammoniakk sammenliknet med laksefisk. Forhøyede nivåer av disse stoffene medfører redusert gonadevekst, mens fôrinntaket blir lite påvirket. Dette resulterer i svært dårlig fôrutnyttelse. Kråkebollene har lavt oksygenforbruk, men er likevel svært følsomme for reduksjoner i vannets oksygeninnhold. Disse forholdene tilsier at kråkeboller i oppdrett krever stor vannutskifting for å opprettholde maksimal gonadevekst. For høy individtetthet i oppdrett medfører også nedsatt gonadevekst. Arbeidet omfatter en kartlegging av akseptabel tetthet for kråkebolle i oppdrett
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Effects of chronic nitrite exposure on gonad growth in Green Sea urchin Strongylocentrotus droebachiensis
Aquaculture, 2004Co-Authors: Sten I. Siikavuopio, Jørgen S. Christiansen, Trine Dale, Ivar NevermoAbstract:Abstract The effects of nitrite concentration on gonad growth and feed intake in Green Sea urchin Strongylocentrotus droebachiensis were examined. In the first experiment, adult Sea urchins with a mean [standard deviation (S.D.)] live weight of 52.0 (17.2) g were exposed to four concentrations of nitrite [0, (control), 0.6 (low), 1.0 (medium) and 2.0 mg N–NO 2 l −1 (high)] for 21 days at 9.0 °C, salinity 33 ppt and pH 8.0. In the second experiment, adult Sea urchins with a mean (S.D.) live weight of 57.6 (16.2) g were exposed to four concentrations of nitrite [0, (control), 2.0 (low), 4.8 (medium) and 10.0 mg N–NO 2 l −1 (high)] for 42 days at 9.2 °C, 33 ppt and pH 8.0. No mortality occurred in any of the experimental groups throughout the study. Gonad growth was significantly reduced by increased nitrite concentrations, with reduced gonadal indices already being apparent at 0.5 mg N–NO 2 l −1 . No significant difference in feed intake was observed between treatment groups. The reduction in gonad growth was not attributed to a decrease in feed intake but rather to impaired food conversion efficiency. The present study demonstrates that adult Green Sea urchins show low tolerance to nitrite and are unable to maintain high gonad growth facing such conditions.
