Fabio Brambilla - Academia.edu (original) (raw)

Papers by Fabio Brambilla

Italian Journal of Animal Science, 2010

Fundamentally, in land based mediterranean aquaculture, two techniques are applied to supply wate... more Fundamentally, in land based mediterranean aquaculture, two techniques are applied to supply water with oxygen: paddling water aeration and application of pure oxygen. The two oxygenation techniques result in quite different PO2 regimens and, consequently, different fish growth performance and gill morphology.

Ecological Indicators, 2011

The impact of an off-shore fish farm in Alghero Bay (northwest Sardinia, Italy) on the benthic ec... more The impact of an off-shore fish farm in Alghero Bay (northwest Sardinia, Italy) on the benthic ecosystem was investigated in 2007 and 2008. In addition to studying the chemical and physical characteristics of the area (i.e., currents and sediment analyses), some biological analyses were also performed. The AZTI's Marine Biotic Index (AMBI) and the multivariate AMBI (M-AMBI) were calculated, which are being used in assessing the ecological status of benthic communities within the European Water Framework Directive (WFD). Clear impact gradients were detected according to both methods; they are related to farm production, prevailing currents, and characteristics of the area (i.e., water depth and distance to the cages). The site affected most was detected within 84 m from the cages; the area that no longer showed effects was over 907 m from the cages. The gradient is shown by decreasing AMBI values and percentage of opportunistic species and increasing richness, diversity, and the presence of sensitive species. This study highlights the importance of setting reference conditions for different areas when calculating M-AMBI. These reference conditions correspond to those in undisturbed sites in the opposite direction of the prevailing currents within the area.

Italian Journal of Animal Science, 2010

Marine fish farming generates particulate wastes which are dispersed in the sea environment. To d... more Marine fish farming generates particulate wastes which are dispersed in the sea environment. To deal with this problem, particulate waste dispersion models have been developed to predict the effects of fish cage culture. In this study, we evaluated the seabed deposition of a fish farming facility located in the central western Mediterranean by using the Meramod ® model. The objectives where first to assess the actual scenario, and second to forecast the possible impact due to the forthcoming enlargement of the farming area with the addition of new fish cages. By computing the hydrodynamic measurements and the daily amount of feed recorded between July and December 2006, the impact seabed surfaces forecasted by the model increased from 5.6ha in the actual scenario, up to 7.3ha in the future. The model estimated a maximum level of total solid flux deposition of 3,800g/m 2 bed/year and a maximum level of total carbon flux deposition of 1,350g/m 2 bed/year for both scenarios. Furthermore, the model predicted that the installation of 4 new fish cages (with an hypothetical mean daily amount of feed of 50kg/cage) will produce a total solid and carbon flux deposition levels ranging 0-400 and 0-150g/m 2 bed/year respectively, under the new fish cages location.

Aquaculture Research, 2007

Coastal water bodies are a particularly heterogeneous resource, typified by high spatial and temp... more Coastal water bodies are a particularly heterogeneous resource, typified by high spatial and temporal variability that could influence the aquaculture in coastal zones. However, the development of coastal aquaculture may produce negative impacts on the coastal area by the potential release of nutrients and organic matter that can be a source of pollution in receiving waters. The aim of this paper was to evaluate the performance of constructed wetland in controlling the dynamics of deoxygenating matter (organic matter and ammonia) and eutrophicating matter [organic matter and soluble reactive phosphorus (SRP)] in the waters entering (inflow) and flowing out (outflow) from a coastal aquaculture fish farm. We observed that constructed wetland systems are effective in removing fractions of total suspended solids, COD, total ammonia nitrogen and SRP contained in the inflow water with higher efficiency in the spring period (60.37%, 14.89%, 65.38% and 17.6% respectively) than in the summer period (45.10%, 8.06%, 32.43% and 8.00% respectively). Similar pattern was recorded for the treatment of the outflow waters, showing that the wetland system reduced most of the deoxygenating and eutrophicating matter produced as a consequence of feeding and fish metabolic activity. During the summer season, high algae mortality can reduce the performance of the wetland system in the outflow water control; this lower efficiency could be improved by controlling the biomass of algae by vegetation harvesting.

Comparative Biochemistry and Physiology B-biochemistry & Molecular Biology, 2009

Concern over the use of dietary antibiotics in aquaculture has encouraged the industry to search ... more Concern over the use of dietary antibiotics in aquaculture has encouraged the industry to search for alternatives that both enhance performance and afford protection from disease. Bio-Mos ® , derived from the outer cell wall of a specific strain of yeast Saccharomyces cerevisiae (Alltech Inc, USA) is a product that fits these criteria. Here, we present data on the impact of a Bio-Mos ® supplemented diet on the mRNA copy number of the antimicrobial peptide dicentracin, whose transcript regulation has not yet been explored in fish. We analyzed Bio-Mos ® -induced changes in the expression of sea bass (Dicentrarchus labrax) dicentracin, using a one-tube two-temperature real-time RT-PCR with which the gene expression can be absolutely quantified using the standard curve method. Our results revealed that 30 days of feeding fish with diets containing Bio-Mos ® supplemented at either 3‰ or 5‰ significantly increased the dicentracin mRNA copy number in the head kidney. Furthermore, the mRNA copy number in fish fed at 3‰ was significantly higher than that of the group fed at 5‰ for the same period of feeding Bio-Mos ® . A longer feeding period (60 days) did not further increase the dicentracin transcript levels as compared to the values recorded after 30 days of feeding either in the group fed at 3‰ or in the one fed at 5‰ diet. However, the transcript levels in fish fed at 3‰ proved to be significantly higher than those of the controls after 60 days of feeding. These findings offer new information about the response of antimicrobial peptides at the transcriptional level to diets supplemented with immune response modulators, and support a role of Bio-Mos ® in promoting sea bass nonspecific immune system.

Comparative Biochemistry and Physiology B-biochemistry & Molecular Biology, 2009

The expression and regulation of sodium-independent glucose transporter (GLUT)-2, in relation to ... more The expression and regulation of sodium-independent glucose transporter (GLUT)-2, in relation to hypoxia has not yet been explored in fish or other vertebrates. In this study, the complete open-reading frame for sea bass GLUT2 was isolated and deposited in the GenBank. The predicted 12 transmembrane domains of the protein (508 amino acids) are presented. A phylogenetic tree was constructed on GLUT2 sequences of sea bass and those of other teleost, amphibian, avian, and mammalian species. We also analyzed acute and chronic hypoxia-induced changes in the expression of hepatic GLUT2 mRNA, using one-tube, two-temperature, real-time RT-PCR with which gene expression can be absolutely quantified by the standard curve method. The number of GLUT2 mRNA copies was significantly increased in response to both acute (1.9 mg/L, dissolved oxygen for 4 h) and chronic (4.3 mg/L, DO for 15 days) hypoxia conditions. The hypoxia-related changes in GLUT2 mRNA copy number support the view that GLUT2 is involved in the adaptation response to hypoxia in sea bass, a marine hypoxia-sensitive species. We realize that the GLUT2 mRNA levels in our study do not measure the physiological effects produced by the protein. Thus, we can only speculate that, under hypoxic conditions, GLUT2 probably functions to allow the glucose produced from liver glycogen to leave the hepatocytes.

Aquacultural Engineering, 2008

Journal of Experimental Marine Biology and Ecology, 2009

Hypercapnia (increased blood CO2 pressure), due to an increasing of aquatic PCO2, is a common eve... more Hypercapnia (increased blood CO2 pressure), due to an increasing of aquatic PCO2, is a common event under conditions of intensive aquaculture and in fish a complex set of physiological and biochemical alterations are employed to cope with this environmental stress. Many of these adjustments depend to a large extent on changes in the expression of genes that encode for physiologically

Techniques in Knee Surgery, 2007

Italian Journal of Animal Science, 2010

Fundamentally, in land based mediterranean aquaculture, two techniques are applied to supply wate... more Fundamentally, in land based mediterranean aquaculture, two techniques are applied to supply water with oxygen: paddling water aeration and application of pure oxygen. The two oxygenation techniques result in quite different PO2 regimens and, consequently, different fish growth performance and gill morphology.

Italian Journal of Animal Science, 2010

Eurasian perch (P. fluviatilis) is a very important fish species in Varese lake (N-W Italy). Sinc... more Eurasian perch (P. fluviatilis) is a very important fish species in Varese lake (N-W Italy). Since the second half of 20 th century, perch catches in the lake have steadily decreased and by the end of the '80s the species resulted clearly endangered. The purpose of this study was to investigate growth, mortality and feeding conditions of perch postlarvae, reared in illuminated floating cage in Varese lake, to obtain fingerlings for a restocking program. In June 2006 and 2007, groups of 280 and 300 pre-weaned post-larvae (average body weight 0.64±0.09 g and 0.25±0.08 g respectively P<0.01) were held in an illuminated net cage for 90 days. The cage was illuminated inside from 20:30 p.m. to 6:30 a.m. During the trial, the nightly zooplankton accumulation inside the cage was assessed weekly. At night time the zooplankton biomass, which resulted dominated by Cladocera family, was higher inside the cage than in the lake. In 2006, 322±36 zooplankters L -1 were observed, compared to 945±600 observed in 2007 (P<0.05). In the lake, the number of zooplankters per litre was similar in both years, resulting in 63.3±50.30 and 61.10±45 zooplankters L -1 , respectively on 2006 and 2007. In order to assess perch growth performances, 25 fishes were sampled from the cage every 15-20 days and length (cm) and weight (g) were assessed for each sample. At the end of September, specific growth rate (SGR) and survival rate were assessed. In 2006 the final mean body weight of the perch fry was 4.65±1.47 g and that results significantly lower (P<0.05) than of 2007 (6.3±1.69 g). The SGR was 2.04% and 3.42%, respectively. The higher growth rate observed in 2007 was influenced by a higher zooplankton accumulation in the cage due to an improved cage management. In order to assess the cage efficiency, in September 2006 and 2007, the weight of young-of-year perch (n=50) captured in the lake were compared to those of reared fish. Wild fry showed a mean body weight significantly higher (P<0.05) than reared ones 15.90±4.25 g and 17.86±4.47 g in 2006 and 2007, respectively). The survival percentages resulted 50.7% in 2006 and 60.7% in 2007. The results demonstrate that the rearing of perch in illuminated floating cages enables the possibility to produce fry for restocking programs in Varese lake. This work is licensed under a Creative Commons Attribution 3.0 License (by-nc 3.0). ©Copyright P.

Italian Journal of Animal Science, 2010

Aquatic hypoxia is a frequent event and in fish a complex set of physiological and biochemical al... more Aquatic hypoxia is a frequent event and in fish a complex set of physiological and biochemical alterations are employed to cope with this environmental stress. Many of these adjustments depend to a large extent on changes in the expression of genes that encode for physiologically relevant proteins. Genes that are induced by hypoxia appear to share a common mode of transcriptional regulation. This induction depends upon activation of a transcription factor, the hypoxia inducible factor-1 (HIF-1), which is a heterodimer composed of two subunits: α ‧ and β. In this study we report first on the molecular cloning and characterization of HIF-1α ‧ in sea bass (Dicentrarchus labrax). The full-length sea bass cD�A for HIF-1α was isolated and deposited in the GenBank with accession no. DQ171936. It consists of 3317 base pairs (bp) carrying a single open-reading frame that encompasses 2265 bp of the coding region and 1052 bp of the 3' UTR.

Italian Journal of Animal Science, 2010

Astaxanthin is one of the major carotenoids in aquatic animals including salmonid fishes and is t... more Astaxanthin is one of the major carotenoids in aquatic animals including salmonid fishes and is the preferred pigments added to salmon feed. It's also a powerful antioxidant compared to other carotenoids and that may confer numerous health benefits. The aim of the present experiment was to investigate the effect of Astaxanthin deposition on the lipids peroxidation by studying the Malondialdeide (MDA) level in muscle of rainbow trout (Oncorhynchus mykiss). The Astaxanthin concentrations in fish fed with a commercial sources as Lucantin ® Pink (BASF Ludwigshafen, Germany) reached values to 5.76±0.18x10 -3 mg/g after 50 days feeding, while the MDA concentration decreased from 1.56x10 3 to 0.45x10 3 ng/g. The correlation between MDA and Astaxanthin concentrations decreased linearly and confirmed the antioxidant properties of the pigment by reducing the lipids peroxidation.

Fisheries Science, 2011

No data have previously been reported on Eurasian perch Perca fluviatilis L. in Lake Varese. In t... more No data have previously been reported on Eurasian perch Perca fluviatilis L. in Lake Varese. In this study, the growth, diet, and reproductive biology of the Eurasian perch population were investigated with the aim of providing information that may serve as a basis for efficient resource management. A total of 240 specimens were caught during the monthly sampling campaign from November 2006 through October 2008. The length-to-weight relationships were W t = 8.4 × 10−3 L t3.10 (males) and W t = 4.1 × 10−3 L t3.36 (females). The parameters for the von Bertalanffy growth function for pooled sexes were L ∞ = 33.17 cm, k = 0.20 year−1, and t 0 = −1.34 year. Perch in Lake Varese spawn from April through May. Sexual maturity is reached when males are 2 years old, in females mostly when they are 3 years old. Relative fecundity (F rel) and absolute fecundity (F abs) were assessed for females. Fecundity values were similar to data reported for other European populations: females of age 2+ F rel = 102,457 ± 12,275, age 3+ F rel = 131,767 ± 5,891, and age 4+ F rel = 131,252 ± 15,555. Perch diet spectrum was wide and somewhat characterized by season. Perch in Lake Varese feed on macroinvertebrates, mainly Chironomidae and Chaoborus, zooplankton, and juvenile rudd Scardinius erythrophthalmus.

Ecological Indicators, 2011

The impact of an off-shore fish farm in Alghero Bay (northwest Sardinia, Italy) on the benthic ec... more The impact of an off-shore fish farm in Alghero Bay (northwest Sardinia, Italy) on the benthic ecosystem was investigated in 2007 and 2008. In addition to studying the chemical and physical characteristics of the area (i.e., currents and sediment analyses), some biological analyses were also performed. The AZTI's Marine Biotic Index (AMBI) and the multivariate AMBI (M-AMBI) were calculated, which are being used in assessing the ecological status of benthic communities within the European Water Framework Directive (WFD). Clear impact gradients were detected according to both methods; they are related to farm production, prevailing currents, and characteristics of the area (i.e., water depth and distance to the cages). The site affected most was detected within 84 m from the cages; the area that no longer showed effects was over 907 m from the cages. The gradient is shown by decreasing AMBI values and percentage of opportunistic species and increasing richness, diversity, and the presence of sensitive species. This study highlights the importance of setting reference conditions for different areas when calculating M-AMBI. These reference conditions correspond to those in undisturbed sites in the opposite direction of the prevailing currents within the area.

Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology, 2009

Concern over the use of dietary antibiotics in aquaculture has encouraged the industry to search ... more Concern over the use of dietary antibiotics in aquaculture has encouraged the industry to search for alternatives that both enhance performance and afford protection from disease. Bio-Mos ® , derived from the outer cell wall of a specific strain of yeast Saccharomyces cerevisiae (Alltech Inc, USA) is a product that fits these criteria. Here, we present data on the impact of a Bio-Mos ® supplemented diet on the mRNA copy number of the antimicrobial peptide dicentracin, whose transcript regulation has not yet been explored in fish. We analyzed Bio-Mos ® -induced changes in the expression of sea bass (Dicentrarchus labrax) dicentracin, using a one-tube two-temperature real-time RT-PCR with which the gene expression can be absolutely quantified using the standard curve method. Our results revealed that 30 days of feeding fish with diets containing Bio-Mos ® supplemented at either 3‰ or 5‰ significantly increased the dicentracin mRNA copy number in the head kidney. Furthermore, the mRNA copy number in fish fed at 3‰ was significantly higher than that of the group fed at 5‰ for the same period of feeding Bio-Mos ® . A longer feeding period (60 days) did not further increase the dicentracin transcript levels as compared to the values recorded after 30 days of feeding either in the group fed at 3‰ or in the one fed at 5‰ diet. However, the transcript levels in fish fed at 3‰ proved to be significantly higher than those of the controls after 60 days of feeding. These findings offer new information about the response of antimicrobial peptides at the transcriptional level to diets supplemented with immune response modulators, and support a role of Bio-Mos ® in promoting sea bass nonspecific immune system.

Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology, 2009

The expression and regulation of sodium-independent glucose transporter (GLUT)-2, in relation to ... more The expression and regulation of sodium-independent glucose transporter (GLUT)-2, in relation to hypoxia has not yet been explored in fish or other vertebrates. In this study, the complete open-reading frame for sea bass GLUT2 was isolated and deposited in the GenBank. The predicted 12 transmembrane domains of the protein (508 amino acids) are presented. A phylogenetic tree was constructed on GLUT2 sequences of sea bass and those of other teleost, amphibian, avian, and mammalian species. We also analyzed acute and chronic hypoxia-induced changes in the expression of hepatic GLUT2 mRNA, using one-tube, two-temperature, real-time RT-PCR with which gene expression can be absolutely quantified by the standard curve method. The number of GLUT2 mRNA copies was significantly increased in response to both acute (1.9 mg/L, dissolved oxygen for 4 h) and chronic (4.3 mg/L, DO for 15 days) hypoxia conditions. The hypoxia-related changes in GLUT2 mRNA copy number support the view that GLUT2 is involved in the adaptation response to hypoxia in sea bass, a marine hypoxia-sensitive species. We realize that the GLUT2 mRNA levels in our study do not measure the physiological effects produced by the protein. Thus, we can only speculate that, under hypoxic conditions, GLUT2 probably functions to allow the glucose produced from liver glycogen to leave the hepatocytes.

Aquaculture Research, 2007

Coastal water bodies are a particularly heterogeneous resource, typi¢ed by high spatial and tempo... more Coastal water bodies are a particularly heterogeneous resource, typi¢ed by high spatial and temporal variability that could in£uence the aquaculture in coastal zones. However, the development of coastal aquaculture may produce negative impacts on the coastal area by the potential release of nutrients and organic matter that can be a source of pollution in receiving waters. The aim of this paper was to evaluate the performance of constructed wetland in controlling the dynamics of deoxygenating matter (organic matter and ammonia) and eutrophicating matter [organic matter and soluble reactive phosphorus (SRP)] in the waters entering (in£ow) and £owing out (out£ow) from a coastal aquaculture ¢sh farm. We observed that constructed wetland systems are e¡ective in removing fractions of total suspended solids, COD, total ammonia nitrogen and SRP contained in the in£ow water with higher e⁄ciency in the spring period (60.37%, 14.89%, 65.38% and 17.6% respectively) than in the summer period (45.10%, 8.06%, 32.43% and 8.00% respectively). Similar pattern was recorded for the treatment of the out£ow waters, showing that the wetland system reduced most of the deoxygenating and eutrophicating matter produced as a consequence of feeding and ¢sh metabolic activity. During the summer season, high algae mortality can reduce the performance of the wetland system in the out£ow water control; this lower e⁄ciency could be improved by controlling the biomass of algae by vegetation harvesting.

Aquacultural Engineering, 2008

Italian Journal of Animal Science, 2010

Fundamentally, in land based mediterranean aquaculture, two techniques are applied to supply wate... more Fundamentally, in land based mediterranean aquaculture, two techniques are applied to supply water with oxygen: paddling water aeration and application of pure oxygen. The two oxygenation techniques result in quite different PO2 regimens and, consequently, different fish growth performance and gill morphology.

Ecological Indicators, 2011

The impact of an off-shore fish farm in Alghero Bay (northwest Sardinia, Italy) on the benthic ec... more The impact of an off-shore fish farm in Alghero Bay (northwest Sardinia, Italy) on the benthic ecosystem was investigated in 2007 and 2008. In addition to studying the chemical and physical characteristics of the area (i.e., currents and sediment analyses), some biological analyses were also performed. The AZTI's Marine Biotic Index (AMBI) and the multivariate AMBI (M-AMBI) were calculated, which are being used in assessing the ecological status of benthic communities within the European Water Framework Directive (WFD). Clear impact gradients were detected according to both methods; they are related to farm production, prevailing currents, and characteristics of the area (i.e., water depth and distance to the cages). The site affected most was detected within 84 m from the cages; the area that no longer showed effects was over 907 m from the cages. The gradient is shown by decreasing AMBI values and percentage of opportunistic species and increasing richness, diversity, and the presence of sensitive species. This study highlights the importance of setting reference conditions for different areas when calculating M-AMBI. These reference conditions correspond to those in undisturbed sites in the opposite direction of the prevailing currents within the area.

Italian Journal of Animal Science, 2010

Marine fish farming generates particulate wastes which are dispersed in the sea environment. To d... more Marine fish farming generates particulate wastes which are dispersed in the sea environment. To deal with this problem, particulate waste dispersion models have been developed to predict the effects of fish cage culture. In this study, we evaluated the seabed deposition of a fish farming facility located in the central western Mediterranean by using the Meramod ® model. The objectives where first to assess the actual scenario, and second to forecast the possible impact due to the forthcoming enlargement of the farming area with the addition of new fish cages. By computing the hydrodynamic measurements and the daily amount of feed recorded between July and December 2006, the impact seabed surfaces forecasted by the model increased from 5.6ha in the actual scenario, up to 7.3ha in the future. The model estimated a maximum level of total solid flux deposition of 3,800g/m 2 bed/year and a maximum level of total carbon flux deposition of 1,350g/m 2 bed/year for both scenarios. Furthermore, the model predicted that the installation of 4 new fish cages (with an hypothetical mean daily amount of feed of 50kg/cage) will produce a total solid and carbon flux deposition levels ranging 0-400 and 0-150g/m 2 bed/year respectively, under the new fish cages location.

Aquaculture Research, 2007

Coastal water bodies are a particularly heterogeneous resource, typified by high spatial and temp... more Coastal water bodies are a particularly heterogeneous resource, typified by high spatial and temporal variability that could influence the aquaculture in coastal zones. However, the development of coastal aquaculture may produce negative impacts on the coastal area by the potential release of nutrients and organic matter that can be a source of pollution in receiving waters. The aim of this paper was to evaluate the performance of constructed wetland in controlling the dynamics of deoxygenating matter (organic matter and ammonia) and eutrophicating matter [organic matter and soluble reactive phosphorus (SRP)] in the waters entering (inflow) and flowing out (outflow) from a coastal aquaculture fish farm. We observed that constructed wetland systems are effective in removing fractions of total suspended solids, COD, total ammonia nitrogen and SRP contained in the inflow water with higher efficiency in the spring period (60.37%, 14.89%, 65.38% and 17.6% respectively) than in the summer period (45.10%, 8.06%, 32.43% and 8.00% respectively). Similar pattern was recorded for the treatment of the outflow waters, showing that the wetland system reduced most of the deoxygenating and eutrophicating matter produced as a consequence of feeding and fish metabolic activity. During the summer season, high algae mortality can reduce the performance of the wetland system in the outflow water control; this lower efficiency could be improved by controlling the biomass of algae by vegetation harvesting.

Comparative Biochemistry and Physiology B-biochemistry & Molecular Biology, 2009

Concern over the use of dietary antibiotics in aquaculture has encouraged the industry to search ... more Concern over the use of dietary antibiotics in aquaculture has encouraged the industry to search for alternatives that both enhance performance and afford protection from disease. Bio-Mos ® , derived from the outer cell wall of a specific strain of yeast Saccharomyces cerevisiae (Alltech Inc, USA) is a product that fits these criteria. Here, we present data on the impact of a Bio-Mos ® supplemented diet on the mRNA copy number of the antimicrobial peptide dicentracin, whose transcript regulation has not yet been explored in fish. We analyzed Bio-Mos ® -induced changes in the expression of sea bass (Dicentrarchus labrax) dicentracin, using a one-tube two-temperature real-time RT-PCR with which the gene expression can be absolutely quantified using the standard curve method. Our results revealed that 30 days of feeding fish with diets containing Bio-Mos ® supplemented at either 3‰ or 5‰ significantly increased the dicentracin mRNA copy number in the head kidney. Furthermore, the mRNA copy number in fish fed at 3‰ was significantly higher than that of the group fed at 5‰ for the same period of feeding Bio-Mos ® . A longer feeding period (60 days) did not further increase the dicentracin transcript levels as compared to the values recorded after 30 days of feeding either in the group fed at 3‰ or in the one fed at 5‰ diet. However, the transcript levels in fish fed at 3‰ proved to be significantly higher than those of the controls after 60 days of feeding. These findings offer new information about the response of antimicrobial peptides at the transcriptional level to diets supplemented with immune response modulators, and support a role of Bio-Mos ® in promoting sea bass nonspecific immune system.

Comparative Biochemistry and Physiology B-biochemistry & Molecular Biology, 2009

The expression and regulation of sodium-independent glucose transporter (GLUT)-2, in relation to ... more The expression and regulation of sodium-independent glucose transporter (GLUT)-2, in relation to hypoxia has not yet been explored in fish or other vertebrates. In this study, the complete open-reading frame for sea bass GLUT2 was isolated and deposited in the GenBank. The predicted 12 transmembrane domains of the protein (508 amino acids) are presented. A phylogenetic tree was constructed on GLUT2 sequences of sea bass and those of other teleost, amphibian, avian, and mammalian species. We also analyzed acute and chronic hypoxia-induced changes in the expression of hepatic GLUT2 mRNA, using one-tube, two-temperature, real-time RT-PCR with which gene expression can be absolutely quantified by the standard curve method. The number of GLUT2 mRNA copies was significantly increased in response to both acute (1.9 mg/L, dissolved oxygen for 4 h) and chronic (4.3 mg/L, DO for 15 days) hypoxia conditions. The hypoxia-related changes in GLUT2 mRNA copy number support the view that GLUT2 is involved in the adaptation response to hypoxia in sea bass, a marine hypoxia-sensitive species. We realize that the GLUT2 mRNA levels in our study do not measure the physiological effects produced by the protein. Thus, we can only speculate that, under hypoxic conditions, GLUT2 probably functions to allow the glucose produced from liver glycogen to leave the hepatocytes.

Aquacultural Engineering, 2008

Journal of Experimental Marine Biology and Ecology, 2009

Hypercapnia (increased blood CO2 pressure), due to an increasing of aquatic PCO2, is a common eve... more Hypercapnia (increased blood CO2 pressure), due to an increasing of aquatic PCO2, is a common event under conditions of intensive aquaculture and in fish a complex set of physiological and biochemical alterations are employed to cope with this environmental stress. Many of these adjustments depend to a large extent on changes in the expression of genes that encode for physiologically

Techniques in Knee Surgery, 2007

Italian Journal of Animal Science, 2010

Fundamentally, in land based mediterranean aquaculture, two techniques are applied to supply wate... more Fundamentally, in land based mediterranean aquaculture, two techniques are applied to supply water with oxygen: paddling water aeration and application of pure oxygen. The two oxygenation techniques result in quite different PO2 regimens and, consequently, different fish growth performance and gill morphology.

Italian Journal of Animal Science, 2010

Eurasian perch (P. fluviatilis) is a very important fish species in Varese lake (N-W Italy). Sinc... more Eurasian perch (P. fluviatilis) is a very important fish species in Varese lake (N-W Italy). Since the second half of 20 th century, perch catches in the lake have steadily decreased and by the end of the '80s the species resulted clearly endangered. The purpose of this study was to investigate growth, mortality and feeding conditions of perch postlarvae, reared in illuminated floating cage in Varese lake, to obtain fingerlings for a restocking program. In June 2006 and 2007, groups of 280 and 300 pre-weaned post-larvae (average body weight 0.64±0.09 g and 0.25±0.08 g respectively P<0.01) were held in an illuminated net cage for 90 days. The cage was illuminated inside from 20:30 p.m. to 6:30 a.m. During the trial, the nightly zooplankton accumulation inside the cage was assessed weekly. At night time the zooplankton biomass, which resulted dominated by Cladocera family, was higher inside the cage than in the lake. In 2006, 322±36 zooplankters L -1 were observed, compared to 945±600 observed in 2007 (P<0.05). In the lake, the number of zooplankters per litre was similar in both years, resulting in 63.3±50.30 and 61.10±45 zooplankters L -1 , respectively on 2006 and 2007. In order to assess perch growth performances, 25 fishes were sampled from the cage every 15-20 days and length (cm) and weight (g) were assessed for each sample. At the end of September, specific growth rate (SGR) and survival rate were assessed. In 2006 the final mean body weight of the perch fry was 4.65±1.47 g and that results significantly lower (P<0.05) than of 2007 (6.3±1.69 g). The SGR was 2.04% and 3.42%, respectively. The higher growth rate observed in 2007 was influenced by a higher zooplankton accumulation in the cage due to an improved cage management. In order to assess the cage efficiency, in September 2006 and 2007, the weight of young-of-year perch (n=50) captured in the lake were compared to those of reared fish. Wild fry showed a mean body weight significantly higher (P<0.05) than reared ones 15.90±4.25 g and 17.86±4.47 g in 2006 and 2007, respectively). The survival percentages resulted 50.7% in 2006 and 60.7% in 2007. The results demonstrate that the rearing of perch in illuminated floating cages enables the possibility to produce fry for restocking programs in Varese lake. This work is licensed under a Creative Commons Attribution 3.0 License (by-nc 3.0). ©Copyright P.

Italian Journal of Animal Science, 2010

Aquatic hypoxia is a frequent event and in fish a complex set of physiological and biochemical al... more Aquatic hypoxia is a frequent event and in fish a complex set of physiological and biochemical alterations are employed to cope with this environmental stress. Many of these adjustments depend to a large extent on changes in the expression of genes that encode for physiologically relevant proteins. Genes that are induced by hypoxia appear to share a common mode of transcriptional regulation. This induction depends upon activation of a transcription factor, the hypoxia inducible factor-1 (HIF-1), which is a heterodimer composed of two subunits: α ‧ and β. In this study we report first on the molecular cloning and characterization of HIF-1α ‧ in sea bass (Dicentrarchus labrax). The full-length sea bass cD�A for HIF-1α was isolated and deposited in the GenBank with accession no. DQ171936. It consists of 3317 base pairs (bp) carrying a single open-reading frame that encompasses 2265 bp of the coding region and 1052 bp of the 3' UTR.

Italian Journal of Animal Science, 2010

Astaxanthin is one of the major carotenoids in aquatic animals including salmonid fishes and is t... more Astaxanthin is one of the major carotenoids in aquatic animals including salmonid fishes and is the preferred pigments added to salmon feed. It's also a powerful antioxidant compared to other carotenoids and that may confer numerous health benefits. The aim of the present experiment was to investigate the effect of Astaxanthin deposition on the lipids peroxidation by studying the Malondialdeide (MDA) level in muscle of rainbow trout (Oncorhynchus mykiss). The Astaxanthin concentrations in fish fed with a commercial sources as Lucantin ® Pink (BASF Ludwigshafen, Germany) reached values to 5.76±0.18x10 -3 mg/g after 50 days feeding, while the MDA concentration decreased from 1.56x10 3 to 0.45x10 3 ng/g. The correlation between MDA and Astaxanthin concentrations decreased linearly and confirmed the antioxidant properties of the pigment by reducing the lipids peroxidation.

Fisheries Science, 2011

No data have previously been reported on Eurasian perch Perca fluviatilis L. in Lake Varese. In t... more No data have previously been reported on Eurasian perch Perca fluviatilis L. in Lake Varese. In this study, the growth, diet, and reproductive biology of the Eurasian perch population were investigated with the aim of providing information that may serve as a basis for efficient resource management. A total of 240 specimens were caught during the monthly sampling campaign from November 2006 through October 2008. The length-to-weight relationships were W t = 8.4 × 10−3 L t3.10 (males) and W t = 4.1 × 10−3 L t3.36 (females). The parameters for the von Bertalanffy growth function for pooled sexes were L ∞ = 33.17 cm, k = 0.20 year−1, and t 0 = −1.34 year. Perch in Lake Varese spawn from April through May. Sexual maturity is reached when males are 2 years old, in females mostly when they are 3 years old. Relative fecundity (F rel) and absolute fecundity (F abs) were assessed for females. Fecundity values were similar to data reported for other European populations: females of age 2+ F rel = 102,457 ± 12,275, age 3+ F rel = 131,767 ± 5,891, and age 4+ F rel = 131,252 ± 15,555. Perch diet spectrum was wide and somewhat characterized by season. Perch in Lake Varese feed on macroinvertebrates, mainly Chironomidae and Chaoborus, zooplankton, and juvenile rudd Scardinius erythrophthalmus.

Ecological Indicators, 2011

The impact of an off-shore fish farm in Alghero Bay (northwest Sardinia, Italy) on the benthic ec... more The impact of an off-shore fish farm in Alghero Bay (northwest Sardinia, Italy) on the benthic ecosystem was investigated in 2007 and 2008. In addition to studying the chemical and physical characteristics of the area (i.e., currents and sediment analyses), some biological analyses were also performed. The AZTI's Marine Biotic Index (AMBI) and the multivariate AMBI (M-AMBI) were calculated, which are being used in assessing the ecological status of benthic communities within the European Water Framework Directive (WFD). Clear impact gradients were detected according to both methods; they are related to farm production, prevailing currents, and characteristics of the area (i.e., water depth and distance to the cages). The site affected most was detected within 84 m from the cages; the area that no longer showed effects was over 907 m from the cages. The gradient is shown by decreasing AMBI values and percentage of opportunistic species and increasing richness, diversity, and the presence of sensitive species. This study highlights the importance of setting reference conditions for different areas when calculating M-AMBI. These reference conditions correspond to those in undisturbed sites in the opposite direction of the prevailing currents within the area.

Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology, 2009

Concern over the use of dietary antibiotics in aquaculture has encouraged the industry to search ... more Concern over the use of dietary antibiotics in aquaculture has encouraged the industry to search for alternatives that both enhance performance and afford protection from disease. Bio-Mos ® , derived from the outer cell wall of a specific strain of yeast Saccharomyces cerevisiae (Alltech Inc, USA) is a product that fits these criteria. Here, we present data on the impact of a Bio-Mos ® supplemented diet on the mRNA copy number of the antimicrobial peptide dicentracin, whose transcript regulation has not yet been explored in fish. We analyzed Bio-Mos ® -induced changes in the expression of sea bass (Dicentrarchus labrax) dicentracin, using a one-tube two-temperature real-time RT-PCR with which the gene expression can be absolutely quantified using the standard curve method. Our results revealed that 30 days of feeding fish with diets containing Bio-Mos ® supplemented at either 3‰ or 5‰ significantly increased the dicentracin mRNA copy number in the head kidney. Furthermore, the mRNA copy number in fish fed at 3‰ was significantly higher than that of the group fed at 5‰ for the same period of feeding Bio-Mos ® . A longer feeding period (60 days) did not further increase the dicentracin transcript levels as compared to the values recorded after 30 days of feeding either in the group fed at 3‰ or in the one fed at 5‰ diet. However, the transcript levels in fish fed at 3‰ proved to be significantly higher than those of the controls after 60 days of feeding. These findings offer new information about the response of antimicrobial peptides at the transcriptional level to diets supplemented with immune response modulators, and support a role of Bio-Mos ® in promoting sea bass nonspecific immune system.

Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology, 2009

The expression and regulation of sodium-independent glucose transporter (GLUT)-2, in relation to ... more The expression and regulation of sodium-independent glucose transporter (GLUT)-2, in relation to hypoxia has not yet been explored in fish or other vertebrates. In this study, the complete open-reading frame for sea bass GLUT2 was isolated and deposited in the GenBank. The predicted 12 transmembrane domains of the protein (508 amino acids) are presented. A phylogenetic tree was constructed on GLUT2 sequences of sea bass and those of other teleost, amphibian, avian, and mammalian species. We also analyzed acute and chronic hypoxia-induced changes in the expression of hepatic GLUT2 mRNA, using one-tube, two-temperature, real-time RT-PCR with which gene expression can be absolutely quantified by the standard curve method. The number of GLUT2 mRNA copies was significantly increased in response to both acute (1.9 mg/L, dissolved oxygen for 4 h) and chronic (4.3 mg/L, DO for 15 days) hypoxia conditions. The hypoxia-related changes in GLUT2 mRNA copy number support the view that GLUT2 is involved in the adaptation response to hypoxia in sea bass, a marine hypoxia-sensitive species. We realize that the GLUT2 mRNA levels in our study do not measure the physiological effects produced by the protein. Thus, we can only speculate that, under hypoxic conditions, GLUT2 probably functions to allow the glucose produced from liver glycogen to leave the hepatocytes.

Aquaculture Research, 2007

Coastal water bodies are a particularly heterogeneous resource, typi¢ed by high spatial and tempo... more Coastal water bodies are a particularly heterogeneous resource, typi¢ed by high spatial and temporal variability that could in£uence the aquaculture in coastal zones. However, the development of coastal aquaculture may produce negative impacts on the coastal area by the potential release of nutrients and organic matter that can be a source of pollution in receiving waters. The aim of this paper was to evaluate the performance of constructed wetland in controlling the dynamics of deoxygenating matter (organic matter and ammonia) and eutrophicating matter [organic matter and soluble reactive phosphorus (SRP)] in the waters entering (in£ow) and £owing out (out£ow) from a coastal aquaculture ¢sh farm. We observed that constructed wetland systems are e¡ective in removing fractions of total suspended solids, COD, total ammonia nitrogen and SRP contained in the in£ow water with higher e⁄ciency in the spring period (60.37%, 14.89%, 65.38% and 17.6% respectively) than in the summer period (45.10%, 8.06%, 32.43% and 8.00% respectively). Similar pattern was recorded for the treatment of the out£ow waters, showing that the wetland system reduced most of the deoxygenating and eutrophicating matter produced as a consequence of feeding and ¢sh metabolic activity. During the summer season, high algae mortality can reduce the performance of the wetland system in the out£ow water control; this lower e⁄ciency could be improved by controlling the biomass of algae by vegetation harvesting.

Aquacultural Engineering, 2008