Emergy evaluation and economic analysis of three wetland fish farming systems in Nansi Lake area, China.

PubMed

Zhang, L X; Ulgiati, S; Yang, Z F; Chen, B

2011-03-01

Emergy and economic methods were used to evaluate and compare three fish production models, i.e., cage fish farming system, pond intensive fish rearing system and semi-natural extensive pond fish rearing system, in Nansi Lake area in China in the year 2007. The goal of this study was to understand the benefits and driving forces of selected fish production models from ecological and economic points of view. The study considered input structure, production efficiency, environmental impacts, economic viability and sustainability. Results show that the main difference among the three production systems was the emergy cost for fish feed associated with their feeding system, i.e., feeding on natural biomass such as plankton and grass or on commercial feedstock. As indicated by EYR, ELR and ESI, it can be clearly shown that the intensive production model with commercial feed is not a sustainable pattern. However, the point is that more environmentally sound patterns do not seem able to provide a competitive net profit in the short run. The intensive pond fish farming system had a net profit of 2.57E+03 $/ha, much higher than 1.27E+03 $/ha for cage fish farming system and slightly higher than 2.37E+03 $/ha for semi-natural fish farming system. With regard to the drivers of local farmer's decisions, the accessibility of land for the required use and investment ability determine the farmer's choice of the production model and the scale of operation, while other factors seem to have little effect. Theoretically, the development of environmentally sustainable production patterns, namely water and land conservation measures, greener feed as well as low waste systems is urgently needed, to keep production activities within the carrying capacity of ecosystems. Coupled emergy and economic analyses can provide better insight into the environmental and economic benefits of fish production systems and help solve the problems encountered during policy making. Copyright © 2010 Elsevier Ltd. All rights reserved.

Recycle food wastes into high quality fish feeds for safe and quality fish production.

PubMed

Wong, Ming-Hung; Mo, Wing-Yin; Choi, Wai-Ming; Cheng, Zhang; Man, Yu-Bon

2016-12-01

The amount of food waste generated from modern societies is increasing, which has imposed a tremendous pressure on its treatment and disposal. Food waste should be treated as a valuable resource rather than waste, and turning it into fish feeds would be a viable alternative. This paper attempts to review the feasibility of using food waste to formulate feed pellets to culture a few freshwater fish species, such as grass carp, grey mullet, and tilapia, under polyculture mode (growing different species in the same pond). These species occupy different ecological niches, with different feeding modes (i.e., herbivorous, filter feeding, etc.), and therefore all the nutrients derived from the food waste could be efficiently recycled within the ecosystem. The problems facing environmental pollution and fish contamination; the past and present situation of inland fish culture (focusing on South China); upgrade of food waste based feed pellets by adding enzymes, vitamin-mineral premix, probiotics (yeast), prebiotics, and Chinese medicinal herbs into feeds; and potential health risks of fish cultivated by food waste based pellets are discussed, citing some local examples. It can be concluded that appropriate portions of different types of food waste could satisfy basic nutritional requirements of lower trophic level fish species such as grass carp and tilapia. Upgrading the fish pellets by adding different supplements mentioned above could further elevated the quality of feeds, leading to higher growth rates, and enhanced immunity of fish. Health risk assessments based on the major environmental contaminants (mercury, PAHs and DDTs) in fish flesh showed that fish fed food waste based pellets are safer for consumption, when compared with those fed commercial feed pellets. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of dietary soy sensitivity in snake river cutthroat trout

USDA-ARS?s Scientific Manuscript database

Hatchery-cultured cutthroat trout fed some commercially available rainbow trout feeds display slow growth and increased mortality. Feed characteristics such as buoyancy and texture alter feed acceptance in some fish species but their effects have not been adequately addressed in cutthroat trout. Th...

Effect of maggot (Hermetia illucens) flour in commercial feed on protein retention, energy retention, protein content, and fat content in tilapia (Oreochromis niloticus)

NASA Astrophysics Data System (ADS)

Kurniawan, D. R.; Arief, M.; Agustono; Lamid, M.

2018-04-01

Nile tilapia is a fish with a nature of breeding throughout the year and has a high adaptation. Feed is one of the most important factors that will affect the growth and the sustainability of fish. Maggot is one of the alternative feeds which has function as source of protein.The aim of this research is to ascertain the influence of maggot (Hermetia illucens) flour substitution on commercial feed which affect the retention of energy, retention of protein, and also rough fat and protein of Nile tilapia flesh. The treatment was to substitute the commercial feed with different doses of maggot flour. In this study, the amount of maggot flour substituted on commercial feed is as follows: treatment P0 (0 %), P1 (12 %), P2 (14 %), P3 (16 %) and P4 (18 %). The parameter observed in this study is an effect on to protein retention, energy retention, and also rough fat and protein in Nile tilapia flesh. The result showed the highest protein content was gained from the treatment P4 with 17.267 %. The lowest protein content was 16.344 % obtained in the treatment P0. There was an increasing protein content in Nile tilapia along with the increase of the maggot flour addition in each treatment.

Upgrading food wastes by means of bromelain and papain to enhance growth and immunity of grass carp (Ctenopharyngodon idella).

PubMed

Choi, W M; Lam, C L; Mo, W Y; Wong, M H

2016-04-01

The fast growing of global aquaculture industry accompanied with increasing pressure on the supply and price of traditional feed materials (e.g., fish meal and soy bean meal). This circumstance has urged the need to search alternative sources of feed stuff. Food waste was used as feed stuff in rearing fish which possess substantial protein and lipid. Grass carp are major species reared in Hong Kong with lower nutritional requirements; it is also an ideal species for investigating the feasibility of using food waste as fish feeds for local aquaculture industry. The growth and immunity, reflected by total protein, total immunologlobulin (IgI), and nitroblue tetrazolium (NBT) activity of grass carp blood, were depressed when feeding with food waste feeds without enzymes. However, the supplementation of bromelain and papain in fish feed enhanced the efficient use of food waste by grass carp, which in turn improved the fish immunity. The present results indicated that the addition of those enzymes could enhance the feed utilization by fish and hematological parameters of grass carp, and the improvement on growth and immunity superior to the control (commercial feed) was observed with the addition of bromelain and papain supplement. Addition of 1 and 2 % mixture of bromelain and papain could significantly enhance the lipid utilization in grass carp.

Levels of synthetic antioxidants (ethoxyquin, butylated hydroxytoluene and butylated hydroxyanisole) in fish feed and commercially farmed fish.

PubMed

Lundebye, A-K; Hove, H; Måge, A; Bohne, V J B; Hamre, K

2010-12-01

Several synthetic antioxidants are authorized for use as feed additives in the European Union. Ethoxyquin (EQ) and butylated hydroxytoluene (BHT) are generally added to fish meal and fish oil, respectively, to limit lipid oxidation. The study was conducted to examine the concentrations of EQ, BHT and butylated hydroxyanisole (BHA) in several commercially important species of farmed fish, namely Atlantic salmon, halibut and cod and rainbow trout, as well as concentrations in fish feed. The highest levels of BHT, EQ and BHA were found in farmed Atlantic salmon fillets, and were 7.60, 0.17 and 0.07 mg kg(-1), respectively. The lowest concentrations of the synthetic antioxidants found were in cod. The concentration of the oxidation product ethoxyquin dimer (EQDM) was more than ten-fold higher than the concentration of parent EQ in Atlantic salmon halibut and rainbow trout, whereas this dimer was not detected in cod fillets. The theoretical consumer exposure to the synthetic antioxidants EQ, BHA and BHT from the consumption of farmed fish was calculated. The contribution of EQ from a single portion (300 g) of skinned fillets of the different species of farmed fish would contribute at most 15% of the acceptable daily intake (ADI) for a 60 kg adult. The consumption of farmed fish would not contribute measurably to the intake of BHA; however, a 300 g portion of farmed Atlantic salmon would contribute up to 75% of the ADI for BHT.

Ocean in Motion

NASA Technical Reports Server (NTRS)

1999-01-01

Under a data purchase agreement with Goddard Space Flight Center, Orbital Sciences Corporation has been able to contract building of the Sea-Viewing Wide-Field-of-View Sensor (SeaWIFS). Orbital Sciences was then able commercialized the data that the satellite produces. These data are used to create daily fish finding maps, allowing fishing fleets to focus on locations where many commercially important surface feeding fish, like tuna and swordfish, congregate. In agriculture and forestry, SeaWIFS' images offer an alternative to direct on-site inspection or expensive serial photography.

PCBs and DDE in commercial fish feeds

USGS Publications Warehouse

Mac, Michael J.; Nicholson, L.W.; McCauley, C.A.

1979-01-01

Three commercial fish feeds were analyzed for PCBs and p,p' DDE and were reported in dry weight concentrations. In various sizes of Oregon Moist Pellets, concentrations of PCBs ranged from less than 0.10 to 0.30 I?g/g and those of p,p' DDE from less than 0.01 to 0.47 I?g/g. In Silver Cup, concentrations of PCBs were 0.06 to 0.07 I?g/g, and p,p' DDE, 0.01 to 0.06 I?g/g. Nauplii of brine shrimp (Artemia salina) contained 0.14 I?g/g PCB and 0.03 I?g/g p,p' DDE.

Susceptibility of Pacific herring to viral hemorrhagic septicemia is influenced by diet

USGS Publications Warehouse

Beaulaurier, Joshua; Bickford, N.; Gregg, J.L.; Grady, C.A.; Gannam, A.L.; Winton, J.R.; Hershberger, P.K.

2012-01-01

Groups of specific-pathogen-free Pacific herring Clupea pallasii were highly susceptible to infection by viral hemorrhagic septicemia virus (VHSV); however, the level of mortality was influenced by diet during the 40–71 d before, during, and after the first exposure to the virus. Cumulative mortality was highest among the herring maintained on an experimental soy-based pellet, intermediate among those maintained on a commercially available fish-meal-based pellet, and lowest among those maintained on a second commercially available fish-meal-based pellet containing ß-glucans. Additionally, the herring maintained on the experimental soy-based feed demonstrated less growth than those on the commercially available feeds. The results indicate the importance of standardizing diet during empirical determinations of disease susceptibility and provide insights into the risk factors affecting VHS susceptibility in wild populations.

Survival and passage of ingested New Zealand mudsnails through the intestinal tract of rainbow trout

USGS Publications Warehouse

Bruce, R. Louise; Moffitt, Christine M.; Dennis, Brian

2009-01-01

We conducted laboratory trials to determine the transit time and survival of New Zealand mudsnails Potamopyrgus antipodarum in the gastrointestinal tract of rainbow trout Oncorhynchus mykiss. To assess the rate of snail passage, we force-fed groups of fish a known quantity of snails and then held them in tanks. At selected intervals we removed individual fish from the test tanks and recorded the number of snails, their condition (live or dead), and their location in the gastrointestinal tract (stomach, anterior intestine, and posterior intestine). Feces were removed from tanks and examined for live snails. We repeated evaluations of passage rate and snail survival to determine the effects of varying the number of snails ingested, fish size, snail size, and feeding a commercial diet to fish after snail ingestion. We plotted and modeled gut evacuation using a stochastic model for ordinal data to consider each test variable. Snail passage rates were faster in fish that were fed smaller snails. Surprisingly, fish fed snails and then administered rations of commercial fish feed retained the snails longer in their stomach than did fish that were not administered fish feeds after being fed snails. Increased retention time of snails in the stomach decreased the probability of snail survival when voided in fecal material. Snails that passed through the gastrointestinal tract within 12–24 h of ingestion were often recovered live in fecal samples. However, no live snails were recovered from the posterior intestine or fecal material collected 24 h after ingestion. Using our results we propose potential management options that could reduce the risks of introducing live snails into new locations when stocking fish from infested hatcheries.

Antimicrobial effect of the Biotronic® Top3 supplement and efficacy in protecting rainbow trout (Oncorhynchus mykiss) from infection by Aeromonas salmonicida subsp. salmonicida.

PubMed

Menanteau-Ledouble, Simon; Krauss, Ines; Goncalves, Rui Alexandre; Weber, Barbara; Santos, Gonçalo Abreu; El-Matbouli, Mansour

2017-10-01

Demand for more environmentally friendly practices have led to the adoption of several feed supplements by the fish farming industry. In the present study, we investigated a commercially available formula that includes a mixture of three compounds: organic acids, a phytochemical and Biomin® Permeabilizing Complex. This mixture demonstrated antimicrobial properties in vitro and was able to inhibit growth of multiple species of aquatic bacterial pathogens, including Aeromonas salmonicida. Bacterial challenge was performed using A. salmonicida and three exposure routes: intra-peritoneal injection, immersion, and cohabitation. Mortality rates following infection by injection were significantly decreased in the fish that had received the supplemented feed. Fish infected through the other routes did not show a significant difference in mortality. In term of farming performance, while the fish that had received the feed supplement showed an improvement in weight gain and final weight, these changes were not found to be statistically significant. Similarly, no significant difference was observed in the feed conversion ratio. The results of this study suggest that this feed supplement may be effective at protecting rainbow trout from fish furunculosis. Copyright © 2017. Published by Elsevier Ltd.

Risk assessment of residual DDTs in freshwater and marine fish cultivated around the Pearl River Delta, China.

PubMed

Leung, S Y; Kwok, C K; Nie, X P; Cheung, K C; Wong, M H

2010-02-01

Six species of freshwater fish collected from 10 fishponds in Shunde and Zhongshan, China, four species of marine fishes collected from different mariculture farms [four in Hong Kong (Tung Lung Chau, Ma Wan, Cheung Chau and Kat O) and two in mainland China (Daya Bay and Shenzhen)] together with feed (both trash fish and commercial pellets) and sediment were analyzed for DDTs. Total DDTs in freshwater fish flesh decreased in the order of: carnivores [1742 microg/kg lipid weight (l.w.)] > herbivores (165 microg/kg, l.w.) > omnivores (42.5 microg/kg, l.w.), with the highest concentration detected in mandarin fish (Siniperca chuatsi) (2641 microg/kg, l.w.). For marine fish, snubnose pompano (Trachinotus blochii) and orange-spotted grouper (Epinephelus coioides) collected in Ma Wan contained elevated levels of total DDTs (2590 and 2034 microg/kg l.w., respectively). Trash fish used in both freshwater and marine fish farms contained significantly higher levels (86.5-641 microg/kg l.w.) (p < 0.05) of DDTs than in commercial pellets, but correlations between DDT levels in fish feed and muscle were not significant. The elevated biota-sediment accumulating factor for tilapia (Tilapia mossambicus) (24.1) indicated that accumulation of DDTs from sediment to the fish was evident. It can be concluded that trash fish should not be used for fish culture in order to lower the level of residual DDTs in fish muscle.

Algae in fish feed: performances and fatty acid metabolism in juvenile Atlantic Salmon.

PubMed

Norambuena, Fernando; Hermon, Karen; Skrzypczyk, Vanessa; Emery, James A; Sharon, Yoni; Beard, Alastair; Turchini, Giovanni M

2015-01-01

Algae are at the base of the aquatic food chain, producing the food resources that fish are adapted to consume. Previous studies have proven that the inclusion of small amounts (<10% of the diet) of algae in fish feed (aquafeed) resulted in positive effects in growth performance and feed utilisation efficiency. Marine algae have also been shown to possess functional activities, helping in the mediation of lipid metabolism, and therefore are increasingly studied in human and animal nutrition. The aim of this study was to assess the potentials of two commercially available algae derived products (dry algae meal), Verdemin (derived from Ulva ohnoi) and Rosamin (derived from diatom Entomoneis spp.) for their possible inclusion into diet of Atlantic Salmon (Salmo salar). Fish performances, feed efficiency, lipid metabolism and final product quality were assessed to investigated the potential of the two algae products (in isolation at two inclusion levels, 2.5% and 5%, or in combination), in experimental diets specifically formulated with low fish meal and fish oil content. The results indicate that inclusion of algae product Verdemin and Rosamin at level of 2.5 and 5.0% did not cause any major positive, nor negative, effect in Atlantic Salmon growth and feed efficiency. An increase in the omega-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA) content in whole body of fish fed 5% Rosamin was observed.

Algae in Fish Feed: Performances and Fatty Acid Metabolism in Juvenile Atlantic Salmon

PubMed Central

Norambuena, Fernando; Hermon, Karen; Skrzypczyk, Vanessa; Emery, James A.; Sharon, Yoni; Beard, Alastair; Turchini, Giovanni M.

2015-01-01

Algae are at the base of the aquatic food chain, producing the food resources that fish are adapted to consume. Previous studies have proven that the inclusion of small amounts (<10% of the diet) of algae in fish feed (aquafeed) resulted in positive effects in growth performance and feed utilisation efficiency. Marine algae have also been shown to possess functional activities, helping in the mediation of lipid metabolism, and therefore are increasingly studied in human and animal nutrition. The aim of this study was to assess the potentials of two commercially available algae derived products (dry algae meal), Verdemin (derived from Ulva ohnoi) and Rosamin (derived from diatom Entomoneis spp.) for their possible inclusion into diet of Atlantic Salmon (Salmo salar). Fish performances, feed efficiency, lipid metabolism and final product quality were assessed to investigated the potential of the two algae products (in isolation at two inclusion levels, 2.5% and 5%, or in combination), in experimental diets specifically formulated with low fish meal and fish oil content. The results indicate that inclusion of algae product Verdemin and Rosamin at level of 2.5 and 5.0% did not cause any major positive, nor negative, effect in Atlantic Salmon growth and feed efficiency. An increase in the omega-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA) content in whole body of fish fed 5% Rosamin was observed. PMID:25875839

Comparison of mercury bioaccumulation between wild and mariculture food chains from a subtropical bay of Southern China.

PubMed

Qiu, Yao-Wen; Wang, Wen-Xiong

2016-02-01

Bioaccumulation and trophic transfer of mercury (Hg) both in the natural marine ecosystem and the mariculture ecosystem were studied at Daya Bay, a subtropical bay in Southern China. Averaged Hg concentrations in sediment, phytoplankton, macrophyte, shrimp, crab, shellfish, planktivorous fish, carnivorous fish, farmed pompano, farmed snapper, compound feed and trash fish were 0.074, 0.054, 0.044, 0.098, 0.116, 0.171, 0.088, 0.121, 0.210, 0.125, 0.038 and 0.106 μg g(-1) dw, respectively. These Hg levels were at the low-middle ends of the global range. Positive correlation between Hg concentrations in farmed fish and fish weights/sizes was observed, whereas no clear correlation between Hg concentrations and lipid contents was found. Hg concentrations followed macrophyte < phytoplankton < sediment < planktivorous fish < shrimp < crab < carnivorous fish < shellfish, and commercial feed < trash fish < farmed fish. Hg was biomagnified along the marine food chain in the ecosystem of Daya Bay. Hg levels in the farmed fish were higher than those in the wild fish primarily because of the higher Hg level in fish feed and the smaller size of marine wild fish.

The Effect of Different Feed and Stocking Densities on Growth And Survival Rate Of Blue Swimming Crablets (Portunus pelagicus)

NASA Astrophysics Data System (ADS)

Ariyati, R. W.; Rejeki, S.; Bosma, R. H.

2018-02-01

Blue swimming crab is targeted by commercial fisheries because of the high economic value, good taste, and attractive colors. As a result, the stock is overexploited and fisherman catch market also juveniles. The most sustainable solution would be to stop fishing for commercial trade and to culture this crab from brood to market size. This study aimed to find the best feed and stocking density for the on-growing of crablets. In 20 tanks juvenile crabs with a carapace width±1 cm were stocked in three densities; 40, 60 and 80 crablets / m2, and fed ad-libitum twice a day with either trash fish or pellets of shrimp feed, for 8 weeks. The circular (ᴓ 1.6 m x 1 m) tanks with 1 m3 of water were aerated, and temperature, salinity, dissolved oxygen and pH recorded daily. In the end, growth and survival rates were determined. In general, feeding the crablets at a density of 40 m-2 gave the highest growth. For crablest fed with pellets, the density of 40 m-2 gave significantly better growth than 80 m-2. The crablets at a density 40 m-2 having a fish diet with the density 40 m-2 grew better than 60 and 80 m-2. There was no significant difference between fed used among different densities. The lower densities resulted in higher survival, either on crablets fed with pellets or fish. But, crablets fed the fish diet and cultured in the lowest density (40 m-2) had the highest survival rate.

Comparison study of two procedures for the determination of emamectin benzoate in medicated fish feed.

PubMed

Farer, Leslie J; Hayes, John M

2005-01-01

A new method has been developed for the determination of emamectin benzoate in fish feed. The method uses a wet extraction, cleanup by solid-phase extraction, and quantitation and separation by liquid chromatography (LC). In this paper, we compare the performance of this method with that of a previously reported LC assay for the determination of emamectin benzoate in fish feed. Although similar to the previous method, the new procedure uses a different sample pretreatment, wet extraction, and quantitation method. The performance of the new method was compared with that of the previously reported method by analyses of 22 medicated feed samples from various commercial sources. A comparison of the results presented here reveals slightly lower assay values obtained with the new method. Although a paired sample t-test indicates the difference in results is significant, this difference is within the method precision of either procedure.

7 CFR 760.205 - Eligible producers, owners, and contract growers.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Livestock, Honeybees, and Farm-Raised Fish Program § 760.205 Eligible producers, owners, and contract... producing honey or pollination for commercial use as part of a farming operation and must have had a loss... farm-raised fish producer for feed loss purposes, the participant must have produced eligible farm...

7 CFR 760.205 - Eligible producers, owners, and contract growers.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Livestock, Honeybees, and Farm-Raised Fish Program § 760.205 Eligible producers, owners, and contract... producing honey or pollination for commercial use as part of a farming operation and must have had a loss... farm-raised fish producer for feed loss purposes, the participant must have produced eligible farm...

Performance of Yellowstone and Snake River Cutthroat Trout Fry Fed Seven Different Diets.

USDA-ARS?s Scientific Manuscript database

Five commercial diets and two formulated feeds were fed to initial-feeding Yellowstone cutthroat trout Oncorhynchus clarkii bouvieri fry and Snake River cutthroat trout O. clarkii spp. (currently being petitioned for classification as O. clarkii behnkei) fry for 18 weeks to evaluate fish performance...

Functional Feed Assessment on Litopenaeus vannamei Using 100% Fish Meal Replacement by Soybean Meal, High Levels of Complex Carbohydrates and Bacillus Probiotic Strains

PubMed Central

Olmos, Jorge; Ochoa, Leonel; Paniagua-Michel, Jesus; Contreras, Rosalia

2011-01-01

Functional feed supplemented with alternative-economic nutrient sources (protein, carbohydrates, lipids) and probiotics are being considered in shrimp/fish aquaculture production systems as an option to increase yield and profits and to reduce water pollution. In this study the probiotic potential to formulate functional feeds have been evaluated using four dietary treatments: Treatment 1 (B + Bs); Bacillus subtilis potential probiotic strain was supplemented to a soybeanmeal (SBM)—carbohydrates (CHO) basal feed. Treatment 2 (B + Bm); Bacillus megaterium potential probiotic strain was supplemented to the same SBM-CHO basal feed. In Treatment 3 (B); SBM-CHO basal feed was not supplemented with probiotic strains. Treatment 4 (C); fishmeal commercial feed (FM) was utilized as positive control. Feeding trials evaluated the survival, growth, and food conversion ratio and stress tolerance of juvenile Litopenaeus vannamei (Boone) Pacific white shrimp. Best overall shrimp performance was observed for animals fed with Treatment 1 (B+Bs); additionally, stress tolerance and hemolymph metabolites also showed the best performance in this treatment. SBM-CHO basal feed not supplemented with probiotic strains (B) presented smaller growth and lower feed conversion ratio (FCR). Shrimps fed with the fishmeal commercial feed (C) presented the lowest stress tolerance to high ammonia and low oxygen levels. Specifically selected B. subtilis strains are recommended to formulate functional and economical feeds containing high levels of vegetable; protein and carbohydrates as main dietary sources in L. vannamei cultures. PMID:21747750

Functional feed assessment on Litopenaeus vannamei using 100% fish meal replacement by soybean meal, high levels of complex carbohydrates and Bacillus probiotic strains.

PubMed

Olmos, Jorge; Ochoa, Leonel; Paniagua-Michel, Jesus; Contreras, Rosalia

2011-01-01

Functional feed supplemented with alternative-economic nutrient sources (protein, carbohydrates, lipids) and probiotics are being considered in shrimp/fish aquaculture production systems as an option to increase yield and profits and to reduce water pollution. In this study the probiotic potential to formulate functional feeds have been evaluated using four dietary treatments: Treatment 1 (B + Bs); Bacillus subtilis potential probiotic strain was supplemented to a soybeanmeal (SBM)-carbohydrates (CHO) basal feed. Treatment 2 (B + Bm); Bacillus megaterium potential probiotic strain was supplemented to the same SBM-CHO basal feed. In Treatment 3 (B); SBM-CHO basal feed was not supplemented with probiotic strains. Treatment 4 (C); fishmeal commercial feed (FM) was utilized as positive control. Feeding trials evaluated the survival, growth, and food conversion ratio and stress tolerance of juvenile Litopenaeus vannamei (Boone) Pacific white shrimp. Best overall shrimp performance was observed for animals fed with Treatment 1 (B+Bs); additionally, stress tolerance and hemolymph metabolites also showed the best performance in this treatment. SBM-CHO basal feed not supplemented with probiotic strains (B) presented smaller growth and lower feed conversion ratio (FCR). Shrimps fed with the fishmeal commercial feed (C) presented the lowest stress tolerance to high ammonia and low oxygen levels. Specifically selected B. subtilis strains are recommended to formulate functional and economical feeds containing high levels of vegetable; protein and carbohydrates as main dietary sources in L. vannamei cultures.

Discrimination between weaned and unweaned Atlantic cod (Gadus morhua) in capture-based aquaculture (CBA) by X-ray imaging and radio-frequency metal detector.

PubMed

Misimi, Ekrem; Martinsen, Svein; Mathiassen, John Reidar; Erikson, Ulf

2014-01-01

The aim of this study was to investigate the feasibility of two detection methods for use in discrimination and sorting of adult Atlantic cod (about 2 kg) in the small scale capture-based aquaculture (CBA). Presently, there is no established method for discrimination of weaned and unweaned cod in CBA. Generally, 60-70% of the wild-caught cod in the CBA are weaned into commercial dry feed. To increase profitability for the fish farmers, unweaned cod must be separated from the stock, meaning the fish must be sorted into two groups - unweaned and weaned from moist feed. The challenges with handling of large numbers of fish in cages, defined the limits of the applied technology. As a result, a working model was established, focusing on implementing different marking materials added to the fish feed, and different technology for detecting the feed presence in the fish gut. X-ray imaging in two modes (planar and dual energy band) and sensitive radio-frequency metal detection were the detection methods that were chosen for the investigations. Both methods were tested in laboratory conditions using dead fish with marked feed inserted into the gut cavity. In particular, the sensitive radio-frequency metal detection method with carbonyl powder showed very promising results in detection of marked feed. Results show also that Dual energy band X-ray imaging may have potential for prediction of fat content in the feed. Based on the investigations it can be concluded that both X-ray imaging and sensitive radio-frequency metal detector technology have the potential for detecting cod having consumed marked feed. These are all technologies that may be adapted to large scale handling of fish from fish cages. Thus, it may be possible to discriminate between unweaned and weaned cod in a large scale grading situation. Based on the results of this study, a suggestion for evaluation of concept for in-situ sorting system is presented.

Leaves from banana (Musa nana) and maize (Zea mays) have no phyto-prophylactic effects on the susceptibility of grass carp (Ctenopharyngodon idella) to Aeromonas hydrophila infection.

PubMed

Mayrhofer, Richard; Menanteau-Ledouble, Simon; Pucher, Johannes; Focken, Ulfert; El-Matbouli, Mansour

2017-11-10

The ubiquitous and opportunistic bacterial pathogen Aeromonas hydrophila has been associated with ulcerative dermatitis in fish, especially under stressful conditions. It can cause severe losses in fresh water aquaculture and is particularly prevalent in tropical and subtropical regions. Fresh leaves from maize and bananas have been used as feed supplement by fish farmers in Vietnam and it has been reported that they may have phyto-prophylactic benefits. In the present study, a feeding trial was conducted to investigate the benefits of providing maize and banana leaves as feed supplement: to determine if they were taken up and digested by grass carp (Ctenopharyngodon idella), if this uptake resulted in improved growth performance, and if leaf supplementation protected fish when challenged with A. hydrophila by intramuscular injection. All fish were fed an identical ratio of commercial pelleted feed relative to biomass. However, in 12/18 tanks, this diet was supplemented with either fresh banana leaves or fresh maize leaves; offered ad libitum. Addition of leaves increased the overall feed conversion ratio (FCR) significantly. However, if only the pellet were taken into account, then no difference was found between treatments. Changes to the isotopic composition of the fish showed leaf nutrient uptake occurred. No prophylactic effects of feeding banana or maize leaves were detected against infection with A. hydrophila, and the diet did not induce changes in the fish haematocrit. However, addition of the maize leaves was associated with significantly reduced severity of the skin lesions, which could improve the market value of the fish. Addition of the leaf supplement did not result in significantly improved growth performance. Similarly, the effect of the supplement on the fish survival to infection was not significant.

Oil from transgenic Camelina sativa containing over 25 % n-3 long-chain PUFA as the major lipid source in feed for Atlantic salmon (Salmo salar).

PubMed

Betancor, Mónica B; Li, Keshuai; Bucerzan, Valentin S; Sprague, Matthew; Sayanova, Olga; Usher, Sarah; Han, Lihua; Norambuena, Fernando; Torrissen, Ole; Napier, Johnathan A; Tocher, Douglas R; Olsen, Rolf E

2018-06-01

Facing a bottleneck in the growth of aquaculture, and a gap in the supply and demand of the highly beneficial n-3 long-chain PUFA (LC-PUFA), sustainable alternatives to traditional marine-based feeds are required. Therefore, in the present trial, a novel oil obtained from a genetically engineered oilseed crop, Camelina sativa, that supplied over 25 % n-3 LC-PUFA was tested as a sole dietary-added lipid source in Atlantic salmon (Salmo salar) feed. Three groups of fish were fed three experimental diets for 12 weeks with the same basal composition and containing 20 % added oil supplied by either a blend of fish oil and rapeseed oil (1:3) (COM) reflecting current commercial formulations, wild-type Camelina oil (WCO) or the novel transgenic Camelina oil (TCO). There were no negative effects on the growth, survival rate or health of the fish. The whole fish and flesh n-3 LC-PUFA levels were highest in fish fed TCO, with levels more than 2-fold higher compared with those of fish fed the COM and WCO diets, respectively. Diet TCO had no negative impacts on the evaluated immune and physiological parameters of head kidney monocytes. The transcriptomic responses of liver and mid-intestine showed only mild effects on metabolism genes. Overall, the results clearly indicated that the oil from transgenic Camelina was highly efficient in supplying n-3 LC-PUFA providing levels double that obtained with a current commercial standard, and similar to those a decade ago before substantial dietary fishmeal and oil replacement.

Combinatorial effects of administration of immunostimulatory compounds in feed and follow-up administration of triple-dose SLICE® (emamectin benzoate) on Atlantic salmon, Salmo salar L., infection with Lepeophtheirus salmonis.

PubMed

Poley, J; Purcell, S L; Igboeli, O O; Donkin, A; Wotton, H; Fast, M D

2013-03-01

Several immunostimulatory feed additives have shown the ability to induce protective responses in Atlantic salmon to infection with Lepeophtheirus salmonis. However, even the most encouraging results rarely surpass a 50% protective index in the host. That fact coupled with the well-documented limitations of single-therapy strategies in the effective management of parasitic infections generally make it imperative to identify therapies that can be combined in an integrated pest management approach for sea lice. With this in mind, we hypothesized that immunostimulatory feeds could enhance the protection provided by SLICE® emamectin benzoate (EMB). To test this hypothesis, Atlantic salmon were fed one of two different immunostimulatory feeds (CpG ODN or Aquate®) for c. 7 weeks, challenged with L. salmonis copepodids early within that immunostimulatory feed period and then placed on a triple-dose (150 μg kg(-1) ) feed of SLICE® for 1 week following the completion of the immunostimulatory feeding period. CpG ODN (2 mg kg(-1) ) and the commercial yeast extract (Aquate® 0.2%) inclusion in feeds were able to successfully induce inflammatory gene expression (interleukin-1β) in the head kidneys of infected fish at 13 and 26 days post-exposure (DPE), and 13 DPE, respectively. Lice burdens were lower on fish fed CpG ODN (18%) or Aquate® (19%) diets; however, due to variability, these were not statistically significant over time. Despite no statistically significant reductions in lice numbers, by 33 DPE fish on immunostimulatory feeds had significantly reduced cortisol levels when compared to infected fish on control diet. Cortisol levels in fish receiving an immunostimulatory diet were no different from initial baseline levels prior to infection, whereas the levels in control diet fish were significantly elevated from all other time points. Despite the positive effects on infection of fish fed immunostimulatory feeds, no synergism was observed with follow-up treatment with SLICE® . In fact, highest survival of lice was observed in fish with prior immunostimulation. © 2013 Blackwell Publishing Ltd.

Channel catfish Ictalurus punctatus size and feed conversion ratio

USDA-ARS?s Scientific Manuscript database

Channel catfish, Ictalurus punctatus, of five size-classes were stocked into 20, 0.04-ha earthen ponds at a rate of 14,826 fish/ha. Mean initial weights for each size-class were 0.232, 0.458, 0.678, 0.911, and 1.10 kg/fish. Four ponds were randomly allotted to each treatment. A commercial 28% protei...

The Marine Fungi Rhodotorula sp. (Strain CNYC4007) as a Potential Feed Source for Fish Larvae Nutrition

PubMed Central

Barra, M.; Llanos-Rivera, A.; Cruzat, F.; Pino-Maureira, N.; González-Saldía, R. R.

2017-01-01

Fish oil is used in the production of feed for cultured fish owing to its high polyunsaturated fatty acid content (PUFA). The over-exploitation of fisheries and events like “El Niño” are reducing the fish oil supply. Some marine microorganisms are considered potentially as alternative fatty acid sources. This study assesses a strain of Rhodotorula sp. (strain CNYC4007; 27% docosahexaenoic acid (DHA) of total fatty acids), as feed for fish larvae. The total length and ribonucleic acid (RNA)/deoxyribonucleic acid (DNA) ratio of Danio rerio larvae was determined at first feeding at six and 12 days old (post-yolk absorption larvae). Larvae fed with microencapsulated Rhodotorula sp. CNYC4007 had a significantly higher RNA/DNA ratio than control group (C1). At six days post-yolk absorption group, the RNA/DNA ratio of larvae fed with Rhodotorula sp. bioencapsulated in Brachionus sp. was significantly higher than control group fed with a commercial diet high in DHA (C2-DHA). Finally, at 12 days post-yolk absorption, the RNA/DNA ratio was significantly higher in larvae fed with Rhodotorula sp. CNYC4007 and C2-DHA (both bioencapsulated in Artemia sp. nauplii) than in control group (C1). These results suggest that Rhodotorula sp. CNYC4007 can be an alternative source of DHA for feeding fish at larval stage, providing a sustainable source of fatty acids. PMID:29194350

Effect of a phytogenic feed additive on the susceptibility of Onchorhynchus mykiss to Aeromonas salmonicida.

PubMed

Menanteau-Ledouble, S; Krauss, I; Santos, G; Fibi, S; Weber, B; El-Matbouli, M

2015-06-29

In recent years, feed additives have increasingly been adopted by the aquaculture industry. These supplements not only offer an alternative to antibiotics but have also been linked to enhanced growth performance. However, the literature is still limited and provides contradictory information on their effectiveness. This is mainly due to the wide variety of available products and their complex mechanisms of action. Phytogenic feed additives have been shown to have antimicrobial effects and can improve growth performance. In the present study, we investigated the susceptibility of several fish pathogenic bacteria to a phytogenic essential oil product in vitro. In addition, we determined the protective effect of a commercial phytogenic feed additive containing oregano, anis and citrus oils on the resistance of rainbow trout Oncorhynchus mykiss to infection by Aeromonas salmonicida. The bacterium was administered through 3 different routes: intra-peritoneal injection, immersion in a bacterial solution and cohabitation with infected fish. Mortality rates were significantly lower in infected rainbow trout that had received the feed additive: the overall mortality rate across all routes of infection was 18% in fish fed a diet containing the additive compared to 37% in fish that received unsupplemented feed. The route of infection also significantly impacted mortality, with average mortality rates of 60, 17.5 and 5% for intra-peritoneal injection, immersion and cohabitation, respectively. In general, fish were better protected against infection by immersion than infection by injection.

Temperature effect on gastric emptying time of hybrid grouper (Epinephelus spp.)

DOE Office of Scientific and Technical Information (OSTI.GOV)

De, Moumita; Ghaffar, Mazlan Abd.; Das, Simon K.

2014-09-03

Knowledge of fish gastric emptying time is a necessary component for understanding the fish feeding rates, energy budgets and commercial production of fishes in aquaculture. The hybrid grouper Epinephelus spp. is getting popular as a culture species in Malaysia for their faster growth rate compared to commonly cultured grouper species (giant grouper Epinephelus lanceolatus and tiger grouper Epinephelus fuscoguttatus). There are data suggests that elevated sea water temperature affects gastric emptying time (GET) of fishes. Hence, this study aims to study the GET of hybrid grouper at different temperature (22, 26, 30, 34°C) in laboratory condition with commercial diet pellet.more » The gastric emptying times (GETs) at different temperatures were determined X-radiographically, using barium sulfate (BaSO{sub 4}) as a contrast medium food marker. The food marker and X-radiography showed that initial voidance of fecal matter began 4-6 h after feeding at all temperature. The fastest GET (13 h) was obsereved in the 30°C group, whereas the longest (17 h) GET was seen in 22°C group fed with artificial diet pellet. Not much differences in GET were recorded between the 26 and 34°C groups as 34°C groups fed lesser amount compared to 26°C groups. Nevertheless a substantial delay in GET was observed in the 22°C group. The findings of this study suggest to culture hybrid grouper between 26 to 30°C with commercial diet pellet as this temperature ranges proliferate the faster digestion process which may contribute faster growth rate of this commerical important fish species. Overall, these findings may have important consequences for optimization of commercial production of hybrid grouper.« less

Temperature effect on gastric emptying time of hybrid grouper (Epinephelus spp.)

NASA Astrophysics Data System (ADS)

De, Moumita; Ghaffar, Mazlan Abd.; Das, Simon K.

2014-09-01

Knowledge of fish gastric emptying time is a necessary component for understanding the fish feeding rates, energy budgets and commercial production of fishes in aquaculture. The hybrid grouper Epinephelus spp. is getting popular as a culture species in Malaysia for their faster growth rate compared to commonly cultured grouper species (giant grouper Epinephelus lanceolatus and tiger grouper Epinephelus fuscoguttatus). There are data suggests that elevated sea water temperature affects gastric emptying time (GET) of fishes. Hence, this study aims to study the GET of hybrid grouper at different temperature (22, 26, 30, 34°C) in laboratory condition with commercial diet pellet. The gastric emptying times (GETs) at different temperatures were determined X-radiographically, using barium sulfate (BaSO4) as a contrast medium food marker. The food marker and X-radiography showed that initial voidance of fecal matter began 4-6 h after feeding at all temperature. The fastest GET (13 h) was obsereved in the 30°C group, whereas the longest (17 h) GET was seen in 22°C group fed with artificial diet pellet. Not much differences in GET were recorded between the 26 and 34°C groups as 34°C groups fed lesser amount compared to 26°C groups. Nevertheless a substantial delay in GET was observed in the 22°C group. The findings of this study suggest to culture hybrid grouper between 26 to 30°C with commercial diet pellet as this temperature ranges proliferate the faster digestion process which may contribute faster growth rate of this commerical important fish species. Overall, these findings may have important consequences for optimization of commercial production of hybrid grouper.

Extruded leftover food as animal feed: I. Effect of extruded feed on growth and feed utilization of tilapia (Oreochromis niloticus) in Saudi Arabia.

PubMed

Al-Ruqaie, Ibrahim M

2007-10-01

A Laboratory experiment was used to evaluate the effect of extruded leftover food as an alternate source of fish diet to Nile tilapia (Oreochromis niloticus, 76.75 +/- 1.27 g). Three experimental diets were used. Two extruded leftover food types [with minerals and vitamins (type-1) and without (type-2) were used to prepare two experimental treatments in duplicate as compared to a commercial tilapia diet (ARASCO) as a control. The final body weight and Specific Growth Rate (SGR) were not affected by different types of leftover feed. Whereas, the Feed Conversion Ratio (FCR) and the Protein Efficiency Ratio (PER) were significantly affected by the different feeds. The highest significant values of FCR was shown for fish fed with extruded leftover feed without premix, while Nile tilapia fed with control diet recorded the highest values of PER. The present study showed that the extruded leftover food could be used to prepare least cost diet for Nile tilapia.

Little Galloo Island, Lake Ontario: A review of nine years of double-crested cormorant diet and fish consumption information

USGS Publications Warehouse

Johnson, James H.; Ross, Robert M.; McCullough, Russ D.

2002-01-01

The diet of double-crested cormorants (Phalacrocorax auritus) on Little Galloo Island (LGI) in the eastern basin of Lake Ontario has been quantified since 1992. Over the past nine years considerable information has been generated on cormorant feeding ecology through the examination of approximately 12,000 pellets collected on LGI, where three distinct cormorant feeding periods, pre-chick, chick, and post-chick, are delineated by differences in diet composition and daily fish consumption. Yellow perch (Perca flavescens) were the major prey during pre-chick and post-chick feeding periods. Alewife (Alosa pseudoharengus), which move inshore to spawn in mid-June, dominated (>60%) cormorant diets during the chick feeding period. Mean daily fish consumption (14.6) during the pre-chick feeding period was significantly greater than during the chick feeding (9.3) or post-chick feeding (8.0) periods. The proportion of smallmouth bass (Micropterus dolomieu) in the diet increased over the season (0.8% to 7.2%), while the size of bass consumed declined (214 mm to 143 mm). Forage fish (mainly alewife, three-spine sticklebacks [Gasterosteus aculeatus] and minnows) comprised 58% of the diet of LGI cormorants, followed by panfish (37%) (yellow perch, pumpkinseed [Lepomis gibbosus], rock bass [Ambloplites rupestris]) and gamefish (5%) (mostly smallmouth bass). On the average LGI cormorants consumed about 32.8 million fish annually, weighing about 1.4 million kilograms. Cormorants from LGI consumed more biomass of smallmouth bass and yellow perch annually than is taken by sport (bass and yellow perch) and commercial (perch) fishermen.

Metabolomics Analysis of Effects of Commercial Soy-based Protein Products in Red Drum (Sciaenops ocellatus).

PubMed

Casu, Fabio; Watson, Aaron M; Yost, Justin; Leffler, John W; Gaylord, Thomas Gibson; Barrows, Frederic T; Sandifer, Paul A; Denson, Michael R; Bearden, Daniel W

2017-07-07

We investigated the metabolic effects of four different commercial soy-based protein products on red drum fish (Sciaenops ocellatus) using nuclear magnetic resonance (NMR) spectroscopy-based metabolomics along with unsupervised principal component analysis (PCA) to evaluate metabolic profiles in liver, muscle, and plasma tissues. Specifically, during a 12 week feeding trial, juvenile red drum maintained in an indoor recirculating aquaculture system were fed four different commercially available soy formulations, containing the same amount of crude protein, and two reference diets as performance controls: a 60% soybean meal diet that had been used in a previous trial in our lab and a natural diet. Red drum liver, muscle, and plasma tissues were sampled at multiple time points to provide a more accurate snapshot of specific metabolic states during the grow-out. PCA score plots derived from NMR spectroscopy data sets showed significant differences between fish fed the natural diet and the soy-based diets, in both liver and muscle tissues. While red drum tolerated the inclusion of soy with good feed conversion ratios, a comparison to fish fed the natural diet revealed that the soy-fed fish in this study displayed a distinct metabolic signature characterized by increased protein and lipid catabolism, suggesting an energetic imbalance. Furthermore, among the soy-based formulations, one diet showed a more pronounced catabolic signature.

Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (South Atlantic): Bluefish

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oliver, J.D.; Van Den Avyle, M.J.; Bozeman, E.L. Jr.

1989-04-01

Species profiles are literature summaries of the life history, distribution, and environmental requirements of coastal fishes and invertebrates. Profiles are prepared to assist with environmental impact assessment. The bluefish (Pomatomus saltatrix) is a valuable recreational and commercial fish on the Atlantic coast. In the South Atlantic Region the recreational catch exceeds the commercial catch. The bluefish is a migratory pelagic fish that generally travels northward in spring and summer and southward in fall and winter along the Atlantic seaboard. In the South Atlantic Region, spawning occurs primarily during spring waters just shoreward of the Gulf Stream form southern North Carolinamore » to Florida. Most larvae are carried northward by the Gulf Stream and are dispersed over the continental slope of the Middle Atlantic Region. Adult bluefish inhabit nearshore areas in the South Atlantic Region during their southerly migration in fall and winter. Larval bluefish eat mostly copepods, cladocerans, and invertebrate eggs; juveniles eat larger invertebrates and fishes. Adult bluefish eat fishes and seem to prefer schooling coastal species. Bluefish have been reported to avoid areas of low dissolved oxygen. Water turbidity may affect feeding because bluefish rely on vision to locate prey. Environmental disturbances which affect the dissolved oxygen concentration or turbidity of estuarine and nearshore waters may, therefore, affect bluefish distribution and feeding. 40 refs., 4 figs., 2 tabs.« less

The alkaline tide and ammonia excretion after voluntary feeding in freshwater rainbow trout.

PubMed

Bucking, Carol; Wood, Chris M

2008-08-01

We investigated the potential acid-base and nitrogenous waste excretion challenges created by voluntary feeding in freshwater rainbow trout, with particular focus on the possible occurrence of an alkaline tide (a metabolic alkalosis created by gastric HCl secretion during digestion). Plasma metabolites (glucose, urea and ammonia) were measured at various time points before and after voluntary feeding to satiation (approximately 5% body mass meal of dry commercial pellets), as was the net flux of ammonia and titratable alkalinity to the water from unfed and fed fish. Arterial blood, sampled by indwelling catheter, was examined for post-prandial effects on pH, plasma bicarbonate and plasma CO2 tension. There was no significant change in plasma glucose or urea concentrations following feeding, whereas plasma ammonia transiently increased, peaking at threefold above resting values at 12 h after the meal and remaining elevated for 24 h. The increased plasma ammonia was correlated with an increase in net ammonia excretion to the water, with fed fish significantly elevating their net ammonia excretion two- to threefold between 12 and 48 h post feeding. These parameters did not change in unfed control fish. Fed fish likewise increased the net titratable base flux to the water by approximately threefold, which resulted in a transition from a small net acid flux seen in unfed fish to a large net base flux in fed fish. Over 48 h, this resulted in a net excretion of 13 867 micromol kg(-1) more base to the external water than in unfed fish. The arterial blood exhibited a corresponding rise in pH (between 6 and 12 h) and plasma bicarbonate (between 3 and 12 h) following feeding; however, no respiratory compensation was observed, as PaCO2 remained constant. Overall, there was evidence of numerous challenges created by feeding in a freshwater teleost fish, including the occurrence of an alkaline tide, and its compensation by excretion of base to the external water. The possible influence of feeding ecology and environmental salinity on these challenges, as well as discrepancies in the literature, are discussed.

Identification and stocking density of elements phosphate indigo system for fish farming cages nets floating in freshwater district Laut Tawar, Aceh Province

NASA Astrophysics Data System (ADS)

Eriyusni, N.; Siregar, A. Z.

2018-02-01

Lake Laut Tawar is located in Aceh district of Aceh province. The lake were used by the community as a livelihood by making a Cages. One of the elements that influence the fish growth is an element Phosphate (PO4) and other such as, pH, nitrate-nitrite, temperature and others. The lake has undergone changes caused by the use of commercial feed. The sampling locations based on the environmental setting by using method "purposive sampling" from January to May. The results was found of 0.1407 mg/L phosphate with fish expenditure amounting to 23728.61 ton / year using cages of net with number as 92, stocking density at 48,950 of fish and marine area 19.77 Ha. However the standard classes showed is under class II Regulation with No. 82 Year 2001 3400, solid lowest stocking cages tail on the size of 2.5 x 2.5 x 3M (spacious, 181m3) with post-harvest fish expenditure amounted to 1,214 tons of fish/year, the highest 9,250 cages tail on the size e of 5 x 5 x 3m (spacious 123m3) with fish expenditure by 2,800 tones of fish/year. While the results of feed conversion and Phosphate content is 12.70% with the Feed Conversion Ratio (FCR) was 1,635 and 1,491.

Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (North Atlantic)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buckley, J.

1989-08-01

Species profiles are literature summaries of the taxonomy, life history, and environmental requirements of coastal fishes and aquatic invertebrates. They are designed to assist with environmental impact assessments. The rainbow smelt is an abundant forage fish for commercially and recreationally valuable fishes such as striped bass and bluefish on the East Coast and several species of salmon and trout in the Great Lakes. The rainbow smelt also supports an important sportfishery throughout most of its range. In 1976, the total smelt harvest in the coastal waters of New England was 105,000 lb. Coastal rainbow smelt are anadromous, spawning in freshwatermore » and maturing in saline water. Spawning peaks in spring. Salinities above 12 ppt were fatal to eggs. Reported fecundities are 7,000 to 44,000 eggs per female. Smelt are always found in shallow water (<6 m deep) and within 2 km of the shore. Larval and juvenile smelt along the coast feed on planktonic crustaceans. Larger juveniles and adults feed on euphausiids, amphipods, on planktonic crustaceans. Larger juveniles and adults feed on euphausiids, amphipods, polychaetes, and fish. Smelt move locally to search for optimum water temperatures. 46 refs., 2 figs., 1 tab.« less

Hypotheses of Spatial Stock Structure in Orange Roughy Hoplostethus atlanticus Inferred from Diet, Feeding, Condition, and Reproductive Activity

PubMed Central

Dunn, Matthew R.; Forman, Jeffrey S.

2011-01-01

We evaluate hypotheses for meso-scale spatial structure in an orange roughy (Hoplostethus atlanticus) stock using samples collected during research trawl surveys off the east coast of New Zealand. Distance-based linear models and generalised additive models were used to identify the most significant biological, environmental, and temporal predictors of variability in diet, proportion of stomachs containing prey, standardised weight of prey, fish somatic weight, fish total weight, and reproductive activity. The diet was similar to that observed elsewhere, and varied with ontogeny, depth, and surface water temperature. Smaller sized and female orange roughy in warmer bottom water were most likely to contain food. Fish condition and reproductive activity were highest at distances more than 20 km from the summit of the hills. Trawl survey catches indicated greater orange roughy densities in hill strata, suggesting hill habitat was favoured. However, analyses of feeding, condition, and reproductive activity indicated hill fish were not superior, despite fish densities on hills being reduced by fishing which, in principle, should have reduced intra-specific competition for food and other resources. Hypotheses for this result include: (1) fish in relatively poor condition visit hills to feed and regain condition and then leave, or (2) commercial fishing has disturbed feeding aggregations and/or caused habitat damage, making fished hills less productive. Mature orange roughy were observed on both flat and hill habitat during periods outside of spawning, and if this spatial structure was persistent then a proportion of the total spawning stock biomass would remain unavailable to fisheries targeting hills. Orange roughy stock assessments informed only by data from hills may well be misleading. PMID:22069464

Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (Gulf of Mexico) - pinfish. [Lagodon rhomboides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muncy, R.J.

1984-09-01

The pinfish (Lagodon rhomboides) is an abundant and important marine fish which can alter estuarine epifaunal seagrass communities as well as serve as forage for commercial and sport fishes. Pinfish have been extensively used in pesticide bioassays, physiological experiments, and ecological studies. Adults and most large juveniles move offshore in late fall. They spawn offshore during fall and winter. Semibuoyant eggs hatch after 48 hours at 18/sup 0/C. Larval pinfish (11 mm TL) move into estuarine nursery grounds soon after hatching, where they feed on calanoid copepods. Juvenile pinfish are most abundant in seagrass-covered habitats where they feed on amphipods.more » Pinfish change their diet as body size and tooth structure changes. Growth increments were 65 to 110 mm, 55 mm, and 45 mm long at the end of their first through third years of life, respectively. Pinfish are used for food and bait by anglers and are combined with unclassified species or industrial fish in commercial fisheries statistics. Pinfish inhabit inshore waters when temperatures are above 10/sup 0/C and below 35/sup 0/C. They are abundant in a broad range of salinities. 99 refs., 2 figs.« less

Effects of copra (Cocos nucifera) meal on the growth performance of Cyprinus carpio

NASA Astrophysics Data System (ADS)

Yusup, Cep Hikmat Maulana; Nugroho, Rudy A.

2017-02-01

This research aimed to evaluate the optimum concentration of copra meal as a fish meal replacement on the growth performance of Cyprinus carpio. Various concentrations of copra (Cocos nucifera) meal, viz 3, 6, 9, and 12 % were used to determine the final weight, body weight gain (BWG), average weekly gain (AWG), daily weight gain (DWG), specific growth rate (SGR), protein efficiency ratio (PER), feed conversion ratio (FCR) of the C. carpio (Initial body weight 25-25.2 g/fish) and compare with control group (Basal diet) without copra meal replacement and commercial diet (CD). Six groups of C. carpio with three replicates were used and fed with different concentration of copra meal at satiation level five times per day for 12 weeks. At the end of feeding trial, the C. carpio fed 9% copra meal in the diet had higher final weight, BWG, AWG, DWG, SGR than any other groups, except commercial diet (CD). Meanwhile, the highest PER was found on the fish fed CD, followed by fish fed 3 % of copra meal in the diet. However, FCR was not affected by any types of diets. These finding suggested that the 9% replacement of wheat in the diet with copra meal is beneficial to improve growth performance.

Food variety in commercial and homemade complementary meals for infants in Germany. Market survey and dietary practice.

PubMed

Mesch, Christina M; Stimming, Madlen; Foterek, Kristina; Hilbig, Annett; Alexy, Ute; Kersting, Mathilde; Libuda, Lars

2014-05-01

Already infants do not meet the recommendations for fruit and vegetable intake although the complementary feeding period offers the possibility to expose the infant to a variety of flavours from fruits and vegetables. The objective of the present analysis was to identify differences in the vegetable variety in commercial vs. homemade complementary meals and to describe fish and meat variety in these meals in dietary practice in Germany. A further objective was to provide an overview of the food variety in commercial complementary vegetable-potato-meat/fish meals available on the German baby food market in 2012. 3-day weighed dietary records from the German DOrtmund Nutritional and Anthropometric Longitudinally Designed (DONALD) study were used to describe the fish and meat variety and to compare the vegetable variety in commercial and homemade meals using a vegetable variety score (VegVS). The online data base 'Nutrichild' served to describe the food variety on the market. The vegetable variety was low in homemade as well as in commercial meals without any differences in total variety at 6 and 9months of age. At 12months of age infants fed with commercial meals got a higher vegetable variety than those fed with homemade meals. In homemade and commercial meals most often carrot was used, whereas other vegetables were far below this frequency. In both meals, poultry and beef were most often used whereas fish meals were rarely offered. The market survey showed the same low vegetable variety and low fish offer as the results of the DONALD study. The data show that it is necessary to promote the advantages of a vegetable variety and fish consumption in Germany, already in early infancy. Copyright © 2014 Elsevier Ltd. All rights reserved.

Distribution of isopod parasites in commercially important marine fishes of the Miri coast, East Malaysia.

PubMed

Anand Kumar, A; Rameshkumar, G; Ravichandran, S; Nagarajan, R; Prabakaran, K; Ramesh, M

2017-03-01

Isopods occur very commonly as parasites in food fishes. Parasitic isopods are typically marine and usually inhabit the warmer seas. They are blood-feeding; several species settle in the buccal cavity of fish, others live in the gill chamber or on the body surface including the fins. Isopods can cause morbidity and mortality in captive fish populations. The infestation usually pressure atrophy often accompanies the presence of larger parasites. The present study was aimed at collecting information on the neglected group of isopod parasites of the marine fishes from the Miri coastal environment, East Malaysia. A very little information available regarding the distribution of isopod parasites of Malaysian coastal environment. In the present study, nine isopod parasites were  oberved from ten marine fish species. The maximum number of parasites were observed in the months of June and October, 2013. Maximum prevalence was observed in October (50 %) and the minimum was observed in June (7.14 %). The parasitic infestation may lead to an economic loss in commercial fish species.

Total mercury levels in commercial fish species from Italian fishery and aquaculture.

PubMed

Di Lena, Gabriella; Casini, Irene; Caproni, Roberto; Fusari, Andrea; Orban, Elena

2017-06-01

Total mercury levels were measured in 42 commercial fish species caught off the Central Adriatic and Tyrrhenian coasts of Italy and in 6 aquaculture species. The study on wild fish covered species differing in living habitat and trophic level. The study on farmed fish covered marine and freshwater species from intensive and extensive aquaculture and their feed. Mercury levels were analysed by thermal decomposition-amalgamation-atomic absorption spectrophotometry. Total mercury concentrations in the muscle of wild fish showed a high variability among species (0.025-2.20 mg kg -1 wet weight). The lowest levels were detected in low trophic-level demersal and pelagic-neritic fish and in young individuals of high trophic-level species. Levels exceeding the European Commission limits were found in large-size specimens of high trophic-level pelagic and demersal species. Fish from intensive farming showed low levels of total mercury (0.008-0.251 mg kg -1 ). Fish from extensive rearing showed variable contamination levels, depending on the area of provenience. An estimation of the human intake of mercury associated to the consumption of the studied fish and its comparison with the tolerable weekly intake is provided.

Carry-over of dietary organochlorine pesticides, PCDD/Fs, PCBs, and brominated flame retardants to Atlantic salmon (Salmo salar L.) fillets.

PubMed

Berntssen, Marc H G; Maage, A; Julshamn, K; Oeye, B E; Lundebye, A-K

2011-03-01

Information on carry-over of contaminants from feed to animal food products is essential for appropriate human risk assessment of feed contaminants. The carry-over of potentially hazardous persistent organic pollutants (POPs) from feed to fillet was assessed in consumption sized Atlantic salmon (Salmo salar). Relative carry-over (defined as the fraction of a certain dietary POP retained in the fillet) was assessed in a controlled feeding trial, which provided fillet retention of dietary organochlorine pesticides (OCPs), dioxins (PCDD/Fs), polychlorinated biphenyls (PCBs), and brominated flame retardants (BFRs). Highest retention was found for OCPs, BFRs and PCBs (31-58%), and the lowest retentions were observed for PCDD/Fs congeners (10-34%). National monitoring data on commercial fish feed and farmed Atlantic salmon on the Norwegian market were used to provide commercially relevant feed-to-fillet transfer factors (calculated as fillet POP level divided by feed POP level), which ranged from 0.4 to 0.5, which is a factor 5-10 times higher than reported for terrestrial meat products. For the OCP with one of the highest relative carry-over, toxaphene, uptake and elimination kinetics were established. Model simulations that are based on the uptake and elimination kinetics gave predicted levels that were in agreement with the measured values. Application of the model to the current EU upper limit for toxaphene in feed (50 μg kg(-1)) gave maximum fillet levels of 22 μg kg(-1), which exceeds the estimated permissible level (21 μg kg(-1)) for toxaphene in fish food samples in Norway. Copyright © 2011 Elsevier Ltd. All rights reserved.

Application of a bioenergetics model for hatchery production: Largemouth bass fed commercial diets

USGS Publications Warehouse

Csargo, Isak J.; Michael L. Brown,; Chipps, Steven R.

2012-01-01

Fish bioenergetics models based on natural prey items have been widely used to address research and management questions. However, few attempts have been made to evaluate and apply bioenergetics models to hatchery-reared fish receiving commercial feeds that contain substantially higher energy densities than natural prey. In this study, we evaluated a bioenergetics model for age-0 largemouth bass Micropterus salmoidesreared on four commercial feeds. Largemouth bass (n ≈ 3,504) were reared for 70 d at 25°C in sixteen 833-L circular tanks connected in parallel to a recirculation system. Model performance was evaluated using error components (mean, slope, and random) derived from decomposition of the mean square error obtained from regression of observed on predicted values. Mean predicted consumption was only 8.9% lower than mean observed consumption and was similar to error rates observed for largemouth bass consuming natural prey. Model evaluation showed that the 97.5% joint confidence region included the intercept of 0 (−0.43 ± 3.65) and slope of 1 (1.08 ± 0.20), which indicates the model accurately predicted consumption. Moreover model error was similar among feeds (P = 0.98), and most error was probably attributable to sampling error (unconsumed feed), underestimated predator energy densities, or consumption-dependent error, which is common in bioenergetics models. This bioenergetics model could provide a valuable tool in hatchery production of largemouth bass. Furthermore, we believe that bioenergetics modeling could be useful in aquaculture production, particularly for species lacking historical hatchery constants or conventional growth models.

Resource recovery from septic tank effluent using duckweed-based tilapia aquaculture.

PubMed

El-Shafai, Saber A; Abdel-Gawad, Fagr Kh; Samhan, Farag; Nasr, Fayza A

2013-01-01

Two parallel duckweed ponds were deployed to utilize nutrients from the effluent of a septic tank treating domestic wastewater. The effluent and fresh biomass of duckweed pond were fed to two subsequent fish ponds stocked with Nile tilapia (Oreochromis niloticus). Fish ponds receiving freshwater and commercial feed were used as control. The results of specific growth rate and feed conversion ratio showed no significant difference between the control ponds and treatment ponds. On the other hand, the total and net fish yields were significantly higher in the control. Microbial analysis revealed contamination of gills, intestine and liver of fish in the treatment ponds. The activity of the immune response genes was up-regulated in the brain and liver of the treatment samples. A micronucleus assay revealed a similar percentage of micronuclei in the polychromatic erythrocytes of blood in the control and treatment samples, while the treatment samples a had higher incidence of micronuclei in the polychromatic erythrocytes of gills, compared with the control.

78 FR 42653 - Taking of Marine Mammals Incidental to Commercial Fishing Operations; Atlantic Large Whale Take...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-16

... through on their way to their Cape Cod Bay feeding ground. Recent passive acoustic studies analyzing right.... (Southern Point, Great Duck Island) 43[deg]59.36' N. lat., 68[deg]37.95' W. long. (R ``2'' Bell, Roaring...

78 FR 66686 - Takes of Marine Mammals Incidental to Specified Activities; Seabird and Pinniped Research...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-06

... (other than commercial fishing) within a specified geographical region if: (1) We make certain findings..., but not limited to, migration, breathing, nursing, breeding, feeding, or sheltering [Level B... seabird colonies; observing seabird nesting habitat; restoring nesting burrows; observing breeding...

Species profiles: Life history and environmental requirements of coastal fishes and invertebrates (South Florida): King mackerel and Spanish mackerel. [Scomberomorus cavalla; Scomberomorus maculatus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Godcharles, M.F.; Murphy, M.D.

1986-06-01

This Species Profile on king and Spanish mackerel summarizes the taxonomy, morphology, distribution, life history, fishery descriptions, ecological role, and environmental requirements of these coastal pelagic fish to assist environmental impact assessment. King and Spanish mackerel support major commercial and sport fisheries in south Florida. In 1974 to 1983, Gulf of Mexico and Atlantic commercial landings of king mackerel declined from 10.4 to 4.3 million lb.; Spanish mackerel have fluctuated between 4.9 to 17.4 million lb. Both inhabit coastal waters, but Spanish mackerel are generally found closer to beaches and in outer estuarine waters. Both species feed principally on estuarine-dependentmore » species. They are highly migratory, exhibiting seasonal migrations to winter feeding grounds off south Florida and summer spawning/feeding grounds in the northern Gulf of Mexico and off the Atlantic coast of the Southeastern US. Spawning occurs from March/April through September/October between the middle and Outer Continental Shelf (35 to 183 mi) for king mackerel and the inner shelf (12 to 34 mi) for Spanish mackerel. King mackerel reach sexual maturity in their 3rd and 4th years and Spanish, between their 2nd and 3rd. Female king mackerel live longer and grow larger and faster than males. Spanish mackerel live to 8 years; females also grow faster than males. King and Spanish mackerel feed principally on schooling fishes. Larvae and juveniles of both species are prey to little tunny and dolphin; adults are prey for sharks and bottlenose dolphin. Temperature and salinity are important factors regulating mackerel distribution.« less

Effects of Glyphosate-Based Herbicide Sub-Lethal Concentrations on Fish Feeding Behavior.

PubMed

Giaquinto, Percilia Cardoso; de Sá, Marina Borges; Sugihara, Vanessa Seiko; Gonçalves, Bruno Bastos; Delício, Helton Carlos; Barki, Assaf

2017-04-01

Glyphosate-based herbicides are widely used in agricultural systems. Although the target organism are particularly plant organisms, there are numerous studies showing adverse effects in aquatic animals, such as inhibition of acetyl cholinesterase, effects on kidney, liver, and gill and stressors effects. This study analyzed the effects of commercial formulation of glyphosate on feeding behavior in Pacu (Piaractus mesopotamicus). Fish were exposed to three glyphosate concentrations (0.2, 0.6, and 1.8 ppm) for 15 days. At concentrations of 0.2 and 0.6 ppm, food intake decreased on day 13 and then returned to normal on day 15. At the highest glyphosate-based herbicide concentration, 1.8 ppm, food consumption decreased dramatically and did not recover on day 15. This study showed that glyphosate-based herbicide at sub-lethal concentrations can affect feed intake in pacu and consequently inhibits its growth.

Feed restriction and insulin-like growth factor-I (IGF-I) affect the oocyte maturation in matrinxã Brycon amazonicus.

PubMed

Montrezor, Luís Henrique; Urbinati, Elisabeth Criscuolo

2017-02-01

The feeding and nutrition of breeders are crucial aspects in the reproductive process. During the maturation period, metabolic changes occur aiming at mobilizing energy for growth and follicular development. The involvement of IGF-1 in metabolic and reproductive events is important. The aim of this work was to evaluate if alternate feed restriction and re-feeding have permissive effects on in vitro actions of IGF-1 on oocytes development of matrinxã. In vivo experiments were performed during vitellogenesis period. Females (n = 60) were fed with a commercial feed (2% of biomass) and they were divided into two treatments: fish receiving food daily (control - fed), and fish submitted to cycles of 3 days of feed restriction and 2 days of re-feeding (no-fed group). For the in vitro experiments, oocytes (n = 20) were obtained from the ovaries removed at the end of the in vivo experiment and were divided into four groups: fed -IGF-1; fed +IGF-1; no-fed -IGF-1 and no-fed +IGF-1. Fish under restriction had lower body weights, decreased plasma glucose, increased triglycerides levels, and their final maturation and mature oocyte were reduced and the atresic ones were in higher number. Moreover, IGF-1, in vitro, increased the percentage of mature oocytes in fed females and decreased the atresic ones. In no-fed females, IGF-1 increased the final maturation and mature oocytes and reduced the atresic ones. This study demonstrates the importance of the feeding management of female breeders of matrinxã during the vitellogenesis period.

Residue depletion of oxytetracycline from fillet tissues of northern pike and walleye

USGS Publications Warehouse

Bernardy, Jeffry A.; Vue, Chue; Gaikowski, Mark P.; Stehly, Guy R.; Gingerich, William H.; Moore, Allen

2003-01-01

The broad-spectrum antibacterial drug oxytetracycline (OTC) is used in the U.S. to treat certain diseases in salmonids and catfish. This study was conducted to support an extension of the OTC label to include all cool-water fish species cultured at U.S. public aquaculture facilities by satisfying human food safety requirements. Juvenile northern pike (Esox lucius; mean weight: 117 g) and walleye (Stizostedion vitreum; mean weight: 59 g) were fed OTC-medicated diets near the maximum legal treatment rate (82.7 mg OTC-HCl/kg fish/day for 10 days) and near the lower limit of the water temperature range for most disease outbreaks in these species (14 and 16 °C, respectively). Two trials were conducted simultaneously with northern pike, one using commercially medicated feed and the other using on-site OTC top-coated feed. A third trial was performed with walleye using on-site OTC top-coated feed. Fillet tissues were collected and OTC free base (OTC-base) concentrations were determined by high performance liquid chromatography. The maximum mean OTC-base concentrations in the fillet tissue were 319 ng/g in northern pike (skinless) and 721 ng/g in walleye (skin-on), both well below the current tolerance limit of 2000 ng/g OTC-base. The log-linear loss of OTC-base from the fillet tissues was monophasic, with terminal phase half-lives of 5.9 days in northern pike fed commercial medicated feed, 6.7 days in northern pike fed top-coated feed, and 10.5 days in walleye fed top-coated feed. The data supported a zero withdrawal time in juvenile northern pike and walleye fed OTC at the approved dose level for 10 days at water temperatures down to 14 and 16 °C respectively.

Growth and feed efficiency of juvenile shrimp Litopenaeus vannamei fed formulated diets containing different levels of poultry by-product meal

NASA Astrophysics Data System (ADS)

Chi, Shuyan; Tan, Beiping; Mai, Kangsen; Zheng, Shixuan

2009-12-01

This feeding trial was conducted to evaluate the potential of poultry by-product meal (PBM) as a protein source in the culture of Litopenaeus vannamei. Seven isonitrogenous and isoenergetic diets were formulated to near to commercial diet with about 40% protein and 7.5% lipid. Fish meal was replaced by 0, 30%, 40%, 50%, 60%, 70% and 100% of PBM (diets 1-7). The diet with 100% fish meal was used as a control (diet 1). Post-larvae were reared in an indoor semi-closed re-circulating system. Each dietary treatment was tested in 4 replicate tanks (260 L) of 40 shrimp, arranged in a completely randomized design. The shrimps were hand-fed for three times a day to near-satiation (0700, 1200 and 1800) for 60 d. Percentage weight gain, survival, feed conversion ratio (FCR), protein efficiency ratio (PER) and body composition of shrimps were measured. There were no significant differences ( P>0.05) in growth performance among shrimps fed diets 1-5 (0-60% fish meal replacement). However, shrimps fed diet 7 (100% fish meal replacement) had significantly lower ( P<0.05) growth than those fed diets 1-5 (0-60% fish meal replacement). Shrimp fed diets 2-4 (30%-50% fish meal replacement) showed significantly higher growth than those fed diets 6 and 7 (70% and 100% fish meal replacement, respectively). Survival ranged from 94.7% to 100.0% and did not differ significantly ( P>0.05) among different experimental diets. No differences in body composition were found among shrimps fed different diets. These results showed that up to 70% of fish meal protein can be replaced by PBM without adversely affecting the growth, survival, FCR, PER and body composition of Litop enaeus vannamei.

Microplastic in the gastrointestinal tract of fishes along the Saudi Arabian Red Sea coast.

PubMed

Baalkhuyur, Fadiyah M; Bin Dohaish, El-Jawaher A; Elhalwagy, Manal E A; Alikunhi, Nabeel M; AlSuwailem, Abdulaziz M; Røstad, Anders; Coker, Darren J; Berumen, Michael L; Duarte, Carlos M

2018-06-01

This study assesses the presence of microplastic litter in the contents of the gastrointestinal tract of 26 commercial and non-commercial fish species from four difference habitats sampled along the Saudi Arabian coast of the Red Sea. A total of 178 individual were examined for microplastics. In total, 26 microplastic fragments were found. Of these, 16 being films (61.5%) and 10 being fishing thread (38.5%). FTIR analysis revealed that the most abundant polymers were polypropylene and polyethylene. The grouper (Epinephelus spp.) sampled at Jazan registered the highest number of ingested microplastics. This fish species is benthic and feeds on benthic invertebrates. Although differences in the abundance of microplastic ingestion among species were not statistically significant, a significant change was observed when the level of ingestion of microplastics particles was compared among the habitats. The higher abundance of microplastics particles may be related to the habitats of fish and the presence of microplastics debris near the seabed. The results of this study represent a first evidence that microplastic pollution represents an emerging threat to Red Sea fishes, their food web and human consumers. Copyright © 2018 Elsevier Ltd. All rights reserved.

A fishmeal-free diet for post-smolt Atlantic salmon in RAS

USDA-ARS?s Scientific Manuscript database

Rising costs and static supply of ocean-harvested fishmeal have spurred decades of research to identify sustainable feed ingredients for salmon diets. There has been substantial progress. The amount of fishmeal and fish oil used in commercial diets has declined and there is now a long list of altern...

Influence of mineral supplementation on growth in yellow perch Perca flavescens fed a soy-based diet

USDA-ARS?s Scientific Manuscript database

Little is known of the nutritional requirements for the growth of yellow perch in intensive aquaculture. Consequently, commercial feed formulations are based on nutritional requirements for rainbow trout, containing large quantities of fish meal and oil which are not optimal for other species. Plant...

Development and on-site field testing of the power-tube airlift aerator and chances for commercialization

USDA-ARS?s Scientific Manuscript database

Aeration of ponds when dissolved oxygen (DO) concentrations are low is the principal management tool that allows for higher feeding rates, increased production, and decreased cost per unit fish produced. Recent research conducted at the USDA-ARS Warmwater Aquaculture Research Unit has shown that fee...

Field trials in Norway with SLICE (0.2% emamectin benzoate) for the oral treatment of sea lice infestation in farmed Atlantic salmon Salmo salar.

PubMed

Ramstad, A; Colquhoun, D J; Nordmo, R; Sutherland, I H; Simmons, R

2002-06-21

Four commercial salmon farms on the West coast of Norway were recruited to a programme of field trials in which the efficacy of SLICE (0.2% emamectin benzoate; Schering-Plough Animal Health) was compared with a commercially available product, EKTOBANN (teflubenzuron 2 g kg(-1); Skretting A/S) in treating natural sea lice Lepeophtheirus salmonis infections in Atlantic salmon Salmo salmar L. At each test site, 3 fish pens were treated with each product. In total, nearly 1.2 million first-year-class fish were included in the trial, of which approximately 561,000 received emamectin benzoate at a dosage of 50 microg kg(-1) body wt d(-1), while approximately 610,000 received teflubenzuron at a dosage of 10 mg kg(-1) body wt d(-1). Medicated feed was provided at 0.5% body wt d(-1) over 7 consecutive days. Feed containing emamectin benzoate was generally well accepted by the fish and no problems were encountered in feeding the medicated diet at the desired dose. Lice numbers were counted 2 d before and 1, 7, 14 and 21 d after commencement of treatment. While treatment with both substances rapidly reduced lice numbers, pens treated with emamectin benzoate were found to harbour significantly fewer lice 14 and 21 d post-treatment. Twenty-one days following treatment with emamectin benzoate the lice abundance was reduced on average by 94%. Limited sampling outside the main study period indicated that emamectin benzoate protects against sea-lice infestation over longer periods.

Effect of commercially available egg cures on the survival of juvenile salmonids

USGS Publications Warehouse

Clements, S.; Chitwood, R.; Schreck, C.B.

2011-01-01

There is some concern that incidental consumption of eggs cured with commercially available cures for the purpose of sport fishing causes mortality in juvenile salmon. We evaluated this by feeding juvenile spring Chinook (Oncorhynchus tshawytscha) and steelhead (O. mykiss) with eggs cured with one of five commercially available cures. We observed significant levels of mortality in both pre-smolts and smolts. Depending on the experiment, 2, 3, or 4 of the cures were associated with mortality. Mortality tended to be higher in the smolts than in the parr, but there was no clear species effect. The majority of mortality occurred within the first 10 d of feeding. Removal of sodium sulfite from the cure significantly reduced the level of mortality. Soaking the eggs prior to feeding did not reduce mortality. We observed a clear relationship between the amount of cured egg consumed each day and the survival time. We conclude that consumption of eggs cured with sodium sulfite has the potential to cause mortality in juvenile steelhead and Chinook salmon in the wild.

Reducing persistent organic pollutants while maintaining long chain omega-3 fatty acid in farmed Atlantic salmon using decontaminated fish oils for an entire production cycle.

PubMed

Berntssen, M H G; Olsvik, P A; Torstensen, B E; Julshamn, K; Midtun, T; Goksøyr, A; Johansen, J; Sigholt, T; Joerum, N; Jakobsen, J-V; Lundebye, A-K; Lock, E-J

2010-09-01

Oily fish are an important source of health promoting nutrients such as the very long chain marine omega-3 (VLC-n3) fatty acids and simultaneously a source of potentially hazardous contaminants. Fish oils that are used in fish feed are the main source for both contaminants and VLC-n3. Decontamination techniques have recently been developed to effectively remove persistent organic contaminants from fish oils. The aim of the present study was to assess the level of potentially hazardous contaminants and the health beneficial fatty acids in Atlantic salmon reared on novel decontaminated feeds. Atlantic salmon were fed for 18 months (an entire seawater production cycle) on diets based on decontaminated or non-treated (control) fish oils until market size (approximately 5 kg). The level of known notorious persistent organic pollutants (POPs, i.e. dioxins, dioxin-like polychlorinated biphenyls (DL-PCBs), non dioxin-like PCBs, poly brominated diphenyl ethers (PBDE), and organochlorine pesticides), as well as fatty acid composition were analysed in fish oils, the two diets, and Atlantic salmon fillet. The oil decontamination process was a two-step procedure using active carbon and short path distillation. The fillet levels of POPs in market size fish were reduced by 68-85% while the concentration of very long chain omega-3 fatty acids was reduced by 4-7%. No differences in biomarkers of dioxin-like component exposures, such as hepatic gene expression of CYP1A or AhR2B, CYP1A protein expression and 7-ethoxyresorufin O-deethylase (EROD) activity, were observed between salmon raised on normal or decontaminated feeds, thus indicating that the difference in POPs levels were of no biological significance to the fish. Atlantic salmon reared on decontaminated feeds had sum polychlorinated dibenzodioxins/furans (PCDD/Fs) and DL-PCB concentrations that were comparable with terrestrial food products such as beef, while the level of marine omega-3 fatty acids remained as high as for commercially farmed Atlantic salmon. (c) 2010 Elsevier Ltd. All rights reserved.

Importance of seagrass-mangrove continuum as feeding grounds for juvenile pink ear emperor Lethrinus lentjan in Setiu Lagoon, Malaysia: Stable isotope approach

NASA Astrophysics Data System (ADS)

Le, Dung Quang; Tanaka, Kentaro; Hii, Yii Siang; Sano, Yuji; Nanjo, Kusuto; Shirai, Kotaro

2018-05-01

The commercially important pink ear emperor fish, Lethrinus lentjan, often occurs as a juvenile in subtropical and tropical interlinked mangrove and seagrass ecosystems, but little is known about its feeding habits and habitat use. Here, we used gut contents and stable isotopic (δ13C and δ15N) ratios to determine temporal changes in food sources and foraging habits of juvenile and sub-adult fish collected in mangrove forests and seagrass beds in the Setiu Lagoon. Gut content examination identified the main food sources as crustaceans, gastropods, bivalves, and annelids. Stable isotope analysis of food sources showed marked differences between the mangroves (δ13C = -26.8 ± 2.0‰; δ15N = 4.3 ± 1.7‰) and the seagrasses (mean ± S.D. δ13C = -20.5 ± 5.5‰; δ15N = 5.8 ± 1.2‰). The isotopic composition of L. lentjan revealed that it mainly utilized seagrass-based food sources. Rainfall and the semi-diurnal tidal regimes may affect the foraging habitats of fish in the lagoon. A significant depletion of 13C related to body size was observed, suggesting that mangroves provided some benefits to sub-adult fish. In contrast, trophic position increased with fish growth, although this increase was negligible. A stable isotope mixing model confirmed that the seagrass bed constituted the main carbon source for the fish, but with an increasing contribution of mangrove prey, such as sesarmid crabs, related to fish growth. This study provided novel information on seasonal variations in feeding areas and flexible habitat use in L. lentjan in the Setiu Lagoon, which will help optimize management strategies for sustainable use and wildlife conservation.

Changes on physiological parameters of tambaqui (Colossoma macropomum) fed with diets supplemented with Amazonian fruit Camu camu (Myrciaria dubia).

PubMed

Aride, P H R; Oliveira, A M; Batista, R B; Ferreira, M S; Pantoja-Lima, J; Ladislau, D S; Castro, P D S; Oliveira, A T

2018-05-01

The physiological responses of juvenile tambaqui (Colossoma macropomum) fed commercial feed supplemented with different concentrations of camu camu (Myrciaria dubia) were evaluated. The design was completely randomized, with treatments arranged in a factorial design with three proportions of camu camu (15%, 30% and 45%) and a control treatment (100% commercial diet), with four replicates per treatment. A total of 96 tambaqui specimens were used, with a mean initial weight of 11.69 ± 2.68 g and a mean length of 7.06 ± 0.44 cm. After 30 days, hematological parameters, metabolic variables, growth and fish swimming performance were evaluated. The different proportions of camu camu in the diet did not cause significant changes to the tambaqui's hematological parameters during the feeding period, except for hemoglobin (Hb) concentration and mean corpuscular hemoglobin concentration (MCHC) after the 30th day, and hematocrit (Ht) after the swimming stress test, which increased significantly (p < 0.05). The significant increases in metabolic variables, such as cortisol, glucose, proteins and triglycerides, and in hematologic variables after the Ucrit test reflect, respectively, biochemical adaptations for maintenance of the energy mobilization process and a regulatory necessity in tissue oxygen demand during intense exercise. Fish fed 15% and 30% camu camu gained the most weight and achieved the best swimming performance, respectively. The results for camu camu concentrations above 30% suggest a saturation of its intrinsic properties in the diet at this level and a loss of nutrients from the commercial feed replaced by the fruit, reducing productive performance and nutritional assimilation.

Environmental health impacts of feeding crops to farmed fish.

PubMed

Fry, Jillian P; Love, David C; MacDonald, Graham K; West, Paul C; Engstrom, Peder M; Nachman, Keeve E; Lawrence, Robert S

2016-05-01

Half of the seafood consumed globally now comes from aquaculture, or farmed seafood. Aquaculture therefore plays an increasingly important role in the global food system, the environment, and human health. Traditionally, aquaculture feed has contained high levels of wild fish, which is unsustainable for ocean ecosystems as demand grows. The aquaculture industry is shifting to crop-based feed ingredients, such as soy, to replace wild fish as a feed source and allow for continued industry growth. This shift fundamentally links seafood production to terrestrial agriculture, and multidisciplinary research is needed to understand the ecological and environmental health implications. We provide basic estimates of the agricultural resource use associated with producing the top five crops used in commercial aquaculture feed. Aquaculture's environmental footprint may now include nutrient and pesticide runoff from industrial crop production, and depending on where and how feed crops are produced, could be indirectly linked to associated negative health outcomes. We summarize key environmental health research on health effects associated with exposure to air, water, and soil contaminated by industrial crop production. Our review also finds that changes in the nutritional content of farmed seafood products due to altered feed composition could impact human nutrition. Based on our literature reviews and estimates of resource use, we present a conceptual framework describing the potential links between increasing use of crop-based ingredients in aquaculture and human health. Additional data and geographic sourcing information for crop-based ingredients are needed to fully assess the environmental health implications of this trend. This is especially critical in the context of a food system that is using both aquatic and terrestrial resources at unsustainable rates. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Impact of oral and waterborne administration of rhamnolipids on the susceptibility of channel catfish (Ictalurus punctatus) to Flavobacterium columnare infection.

PubMed

Zhang, Dongdong; Beck, Benjamin H; Lange, Miles; Zhao, Honggang; Thongda, Wilawan; Ye, Zhi; Li, Chao; Peatman, Eric

2017-01-01

Flavobacterium columnare is the causative agent of columnaris disease and causes tremendous morbidity and mortality of farmed fish globally. Previously, we identified a potential lectin-mediator (a rhamnose-binding lectin; RBL1a) of F. columnare adhesion and showed higher RBL1a expression in susceptible channel catfish under basal conditions and following infection. Exposure of challenged fish to the carbohydrate ligand l-rhamnose just prior to a challenge substantially decreased columnaris mortality and pathogen adherence via the down-regulation of RBL1a. While highly effective in protecting fish from columnaris, l-rhamnose is prohibitively expensive, underscoring the need for alternative cost-effective sources of rhamnose for disease control. One such alternative may be microbially produced glycolipid compounds termed rhamnolipids (RLs), which feature abundant l-rhamnose moieties and are readily available from commercial sources. In the present study, we examined whether commercially available RLs (administered either by immersion or via feed) would function similarly to l-rhamnose in affording host protection against F. columnare. A four-week feeding trial with basal and RL top-coated diets (basal diet + RLs) was conducted in channel catfish fingerlings. Surprisingly, columnaris challenges revealed significantly lower survival following the 10 d challenge period in RL diet fed fish when compared with the basal treatment group (p < 0.001). In fish fed RLs, we observed a rapid and large-scale upregulation of RBL1a immediately after challenge combined with a suppression of mucin and lysozyme transcripts. Similarly, fish that were briefly pre-exposed to RLs by immersion and then challenged exhibited lower survival as compared to unexposed fish during a 4 d trial. In conclusion, RLs do not represent an alternative to rhamnose as an experimental treatment for protecting catfish from columnaris mortality. Further research is needed to find other affordable and efficacious alternative sources of l-rhamnose. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of bottom trawling on fish foraging and feeding.

PubMed

Johnson, Andrew Frederick; Gorelli, Giulia; Jenkins, Stuart Rees; Hiddink, Jan Geert; Hinz, Hilmar

2015-01-22

The effects of bottom trawling on benthic invertebrates include reductions of biomass, diversity and body size. These changes may negatively affect prey availability for demersal fishes, potentially leading to reduced food intake, body condition and yield of fishes in chronically trawled areas. Here, the effect of trawling on the prey availability and diet of two commercially important flatfish species, plaice (Pleuronectes platessa) and dab (Limanda limanda), was investigated over a trawling intensity gradient in the Irish Sea. Previous work in this area has shown that trawling negatively affects the condition of plaice but not of dab. This study showed that reductions in local prey availability did not result in reduced feeding of fish. As trawling frequency increased, both fish and prey biomass declined, such that the ratio of fish to prey remained unchanged. Consequently, even at frequently trawled sites with low prey biomass, both plaice and dab maintained constant levels of stomach fullness and gut energy contents. However, dietary shifts in plaice towards energy-poor prey items were evident when prey species were analysed individually. This, together with a potential decrease in foraging efficiency due to low prey densities, was seen as the most plausible cause for the reduced body condition observed. Understanding the relationship between trawling, benthic impacts, fish foraging and resultant body condition is an important step in designing successful mitigation measures for future management strategies in bottom trawl fisheries.

Effects of bottom trawling on fish foraging and feeding

PubMed Central

Johnson, Andrew Frederick; Gorelli, Giulia; Jenkins, Stuart Rees; Hiddink, Jan Geert; Hinz, Hilmar

2015-01-01

The effects of bottom trawling on benthic invertebrates include reductions of biomass, diversity and body size. These changes may negatively affect prey availability for demersal fishes, potentially leading to reduced food intake, body condition and yield of fishes in chronically trawled areas. Here, the effect of trawling on the prey availability and diet of two commercially important flatfish species, plaice (Pleuronectes platessa) and dab (Limanda limanda), was investigated over a trawling intensity gradient in the Irish Sea. Previous work in this area has shown that trawling negatively affects the condition of plaice but not of dab. This study showed that reductions in local prey availability did not result in reduced feeding of fish. As trawling frequency increased, both fish and prey biomass declined, such that the ratio of fish to prey remained unchanged. Consequently, even at frequently trawled sites with low prey biomass, both plaice and dab maintained constant levels of stomach fullness and gut energy contents. However, dietary shifts in plaice towards energy-poor prey items were evident when prey species were analysed individually. This, together with a potential decrease in foraging efficiency due to low prey densities, was seen as the most plausible cause for the reduced body condition observed. Understanding the relationship between trawling, benthic impacts, fish foraging and resultant body condition is an important step in designing successful mitigation measures for future management strategies in bottom trawl fisheries. PMID:25621336

Requirements of juvenile milkfish (Chanos chanos Forsskal) for essential amino acids.

PubMed

Borlongan, I G; Coloso, R M

1993-01-01

The dietary requirements of juvenile milkfish (Chanos chanos Forsskal) for essential amino acids were determined in a series of experiments. The fish (< or = 8.0 g) were reared in fiber glass tanks provided with flow-through seawater at 28 degrees C and salinity of 32 g/L for 12 wk. In each experiment, a series of amino acid test diets was formulated containing a combination of intact protein sources (casein-gelatin, fish meal-gelatin, fish meal-soybean meal or fish meal-zein) and crystalline amino acids to simulate the levels found in milkfish tissue proteins except for the test amino acid. Each set of isonitrogenous diets contained 40-45% protein and graded levels of the amino acid to be tested. At the end of the feeding experiment, growth, survival and feed efficiency were determined. The requirement level for each essential amino acid was estimated from breakpoint analysis of the growth curve. The dietary essential amino acid requirements (as the percentage of dietary protein) of milkfish juveniles were as follows: arginine, 5.25; histidine, 2.00; isoleucine, 4.00; leucine, 5.11; lysine, 4.00; methionine, 2.50 (cystine, 0.75); phenylalanine, 4.22 (tyrosine, 1.00) or 2.80 (tyrosine, 2.67); threonine, 4.50; tryptophan, 0.60; valine, 3.55. This information is valuable in developing cost-effective practical or commercial feeds and research diets for milkfish juveniles.

Reproductive ecology of Prochilodus brevis an endemic fish from the semiarid Region of Brazil.

PubMed

Gurgel, Liliane de Lima; Verani, José Roberto; Chellappa, Sathyabama

2012-01-01

The commercially important migratory fish Prochilodus brevis is from the Neotropical region, and understanding the reproductive ecology of this potamodromous fish is essential for its conservation and management. This study investigated the length-mass relationship, sex ratio, length at first gonadal maturity, gonadal development stages, gonadosomatic index, condition factor, and reproductive period of P. brevis. Temporal distribution of rainfall, temperature, dissolved oxygen concentration, pH, and electrical conductivity of the water were related to the reproductive period of this fish. Rainfall seems to be the main environmental factor which modulates changes in limnological parameters and the timing of the spawning period of this fish. P. brevis migrates into lower reaches of the river to feed during the dry season and returns to the upper reaches during the rainy season to spawn. Inadequate facilities for migration create obstacles for spawning success of this ecologically important fish.

Commercial trials using emamectin benzoate to control sea lice Lepeophtheirus salmonis infestations in Atlantic salmon Salmo salar.

PubMed

Stone, J; Sutherland, I H; Sommerville, C; Richards, R H; Varma, K J

2000-06-19

Two trials were conducted at commercial salmon farms to evaluate the efficacy of emamectin benzoate (Slice, 0.2% aquaculture pre-mix, Schering-Plough Animal Health) as a treatment for sea lice Lepeophtheirus salmonis (Krøyer) and Caligus elongatus Nordmann infestations in Atlantic salmon Salmo salar L. Trials were carried out in 15 m2 commercial sea pens, at temperatures of 5.5 to 7.5 degrees C and 10.8 to 13.8 degrees C. Each pen was stocked with 14,000 to 17,500 fish with mean weights of 0.44 to 0.74 and 1.33 to 1.83 kg. Fish were naturally infested with sea lice at the start of each trial. At Day -1, samples of 10 or 15 fish were taken from each pen to determine pre-treatment numbers of lice. Emamectin benzoate was administered in feed, to 4 replicate pens, at a dose of 50 micrograms kg-1 biomass d-1 for 7 consecutive days (Days 0 to 6). Sea lice were counted again, between Days 7 and 77, and comparisons made with untreated control fish. Despite adverse weather conditions, wide variations in fish weights and exposure to new infestations, treatment was effective against chalimus and motile stages of L. salmonis. In the autumn trial, efficacy at Day 27 was 89%, and lice numbers remained lower on treated fish than on control fish 64 d from the start of treatment. In the winter trial, reductions in lice numbers at low temperatures were slower but good efficacy was achieved by Day 35. Although control fish had to be treated with hydrogen peroxide at Day 21, fish treated only with emamectin benzoate on Days 0 to 6 still had 89% fewer lice than control fish at Day 35. There were very few C. elongatus present, but at the end of both trials numbers were lower on treated fish. No adverse effects were associated with treatment of fish with emamectin benzoate.

Effects of various feed supplements containing fish protein hydrolysate or fish processing by-products on the innate immune functions of juvenile coho salmon (Oncorhynchus kisutch)

USGS Publications Warehouse

Murray, A.L.; Pascho, R.J.; Alcorn, S.W.; Fairgrieve, W.T.; Shearer, K.D.; Roley, D.

2003-01-01

Immunomodulators administered to fish in the diet have been shown in some cases to enhance innate immune defense mechanisms. Recent studies have suggested that polypeptide fractions found in fish protein hydrolysates may stimulate factors in fish important for disease resistance. For the current study, groups of coho salmon were reared on practical feeds that contained either fish meal (Control diet), fish meal supplemented with cooked fish by-products, or fish meal supplemented with hydrolyzed fish protein alone, or with hydrolyzed fish protein and processed fish bones. For each diet group, three replicate tanks of fish were fed the experimental diets for 6 weeks. Morphometric measurements, and serologic and cellular assays were used to evaluate the general health and immunocompetence of fish in the various feed groups. Whereas the experimental diets had no effect on the morphometric and cellular measurements, fish fed cooked by-products had increased leucocrit levels and lower hematocrit levels than fish from the other feed groups. Innate cellular responses were increased in all feed groups after feeding the four experimental diets compared with pre-feed results. Subgroups of fish from each diet group were also challenged with Vibrio anguillarum (ca. 7.71 ?? 105 bacteria ml-1) at 15??C by immersion. No differences were found in survival among the various feed groups.

Carryover of aflatoxins from feed to lambari fish (Astyanax altiparanae) tissues.

PubMed

Michelin, E C; Massocco, M M; Godoy, S H S; Baldin, J C; Yasui, G S; Lima, C G; Rottinghaus, G E; Sousa, R L M; Fernandes, A M

2017-02-01

The aim of this study was to verify the carryover of aflatoxin B 1 from feed to lambari fish. Aflatoxins (AF) were incorporated into feed, checking the levels by HPLC. Treatments were: Control, feed without toxin; A, feed + 10 µg AFB 1  kg - 1 ; B, feed + 20 µg AFB 1  kg - 1 ; and C, feed + 50 µg AFB 1  kg - 1 . Juveniles of lambari fish were placed in 12 aquariums at a density of 50 fish/m 2 . Fish were fed twice a day with extruded feed, at 5% of animal biomass. The unit sample was constituted by a pool of 10 fish. AFs B 1 , B 2 , G 1 , G 2 and M 1 were quantified by HPLC in fish muscle and liver after 30, 60, 90 and 120 days of experiment. There was accumulation of AFs is fish liver and muscle, mainly after 90 days. Fish from treatment C had higher levels of AFB 1 in muscle when compared with the others, and AFB 1 in muscle at 120 days was similar to the levels in feed. Therefore, when lambari fish is exposed on a daily and long-term basis to AFs in feed, the regulation limits for AFs in animal feed do not guarantee safety for consumers.

An oil containing EPA and DHA from transgenic Camelina sativa to replace marine fish oil in feeds for Atlantic salmon (Salmo salar L.): Effects on intestinal transcriptome, histology, tissue fatty acid profiles and plasma biochemistry

PubMed Central

Betancor, Mónica B.; Li, Keshuai; Sprague, Matthew; Bardal, Tora; Sayanova, Olga; Usher, Sarah; Han, Lihua; Måsøval, Kjell; Torrissen, Ole; Napier, Johnathan A.; Tocher, Douglas R.; Olsen, Rolf Erik

2017-01-01

New de novo sources of omega 3 (n-3) long chain polyunsaturated fatty acids (LC-PUFA) are required as alternatives to fish oil in aquafeeds in order to maintain adequate levels of the beneficial fatty acids, eicosapentaenoic and docosahexaenoic (EPA and DHA, respectively). The present study investigated the use of an EPA+DHA oil derived from transgenic Camelina sativa in Atlantic salmon (Salmo salar) feeds containing low levels of fishmeal (35%) and fish oil (10%), reflecting current commercial formulations, to determine the impacts on tissue fatty acid profile, intestinal transcriptome, and health of farmed salmon. Post-smolt Atlantic salmon were fed for 12-weeks with one of three experimental diets containing either a blend of fish oil/rapeseed oil (FO), wild-type camelina oil (WCO) or transgenic camelina oil (DCO) as added lipid source. The DCO diet did not affect any of the fish performance or health parameters studied. Analyses of the mid and hindgut transcriptomes showed only mild effects on metabolism. Flesh of fish fed the DCO diet accumulated almost double the amount of n-3 LC-PUFA than fish fed the FO or WCO diets, indicating that these oils from transgenic oilseeds offer the opportunity to increase the n-3 LC-PUFA in farmed fish to levels comparable to those found a decade ago. PMID:28403232

An oil containing EPA and DHA from transgenic Camelina sativa to replace marine fish oil in feeds for Atlantic salmon (Salmo salar L.): Effects on intestinal transcriptome, histology, tissue fatty acid profiles and plasma biochemistry.

PubMed

Betancor, Mónica B; Li, Keshuai; Sprague, Matthew; Bardal, Tora; Sayanova, Olga; Usher, Sarah; Han, Lihua; Måsøval, Kjell; Torrissen, Ole; Napier, Johnathan A; Tocher, Douglas R; Olsen, Rolf Erik

2017-01-01

New de novo sources of omega 3 (n-3) long chain polyunsaturated fatty acids (LC-PUFA) are required as alternatives to fish oil in aquafeeds in order to maintain adequate levels of the beneficial fatty acids, eicosapentaenoic and docosahexaenoic (EPA and DHA, respectively). The present study investigated the use of an EPA+DHA oil derived from transgenic Camelina sativa in Atlantic salmon (Salmo salar) feeds containing low levels of fishmeal (35%) and fish oil (10%), reflecting current commercial formulations, to determine the impacts on tissue fatty acid profile, intestinal transcriptome, and health of farmed salmon. Post-smolt Atlantic salmon were fed for 12-weeks with one of three experimental diets containing either a blend of fish oil/rapeseed oil (FO), wild-type camelina oil (WCO) or transgenic camelina oil (DCO) as added lipid source. The DCO diet did not affect any of the fish performance or health parameters studied. Analyses of the mid and hindgut transcriptomes showed only mild effects on metabolism. Flesh of fish fed the DCO diet accumulated almost double the amount of n-3 LC-PUFA than fish fed the FO or WCO diets, indicating that these oils from transgenic oilseeds offer the opportunity to increase the n-3 LC-PUFA in farmed fish to levels comparable to those found a decade ago.

[Periods for growth and quality improvement of fish in context of animal welfare compliant management of commercial fish ponds--a literature review].

PubMed

Pietrock, Michael; Brämick, Uwe

2016-01-01

In Germany, management of commercial fish ponds requires consideration of animal welfare legislation. In particular, it is forbidden to immediately catch fish that have recently been stocked into put-and-take fishponds. Rather, after stocking is completed, a short-term fishing ban period needs to be adhered to that allows the fishes the opportunity to grow and/or significantly improve in overall quality. The duration of the fishing ban varies considerably among German federal states. A literature review, therefore, was undertaken to identify the amount of time required by adult fish to reach changes in various parameters of quality (proximate composition, fillet colour, odour/taste, stress response), and growth.The literature search revealed that some of the selected parameters (odour/taste, stress response) can change within 24 hours, potentially resulting in improved fish flesh quality. With a time span of about four weeks, feeding-induced changes in proximate composition took the longest among the parameters tested to realize significant changes in fish flesh quality. Transportation-related reductions in body mass are overcome and succeeded by net growth within one to two weeks depending on food availability. Maintaining the fish under species-specific conditions and providing the optimal environment to meet their physiological demands, however, are critical prerequisites for growth and quality improvement. In conclusion there is science-based justification for fishing ban periods ranging from 24 hours to four weeks. Final determination of its duration, therefore, remains a careful balancing of values.

Disturbance of Essential Fish Habitat by Commercial Passive Fishing Gear in the Delaware, Maryland, and Virginia region of the Mid-Atlantic Bight

NASA Astrophysics Data System (ADS)

Schweitzer, C.

2016-02-01

Trap fishing is one of the oldest methods utilized to capture fish, and fish traps are currently one of the most dominant fishing gears utilized by commercial fishermen in the DelMarVa (Delaware, Maryland, Virginia) region. Impacts of traps on benthic habitat and emergent epifauna have become an increasing concern since the 1990's, but despite this, there is little published data regarding trap-habitat interactions. Any substrate necessary for fish spawning, breeding, feeding, or growth to maturity is deemed Essential Fish Habitat (EFH) and in order to increase capture success, traps are often deployed near or on EFH. We assessed the degree of trap impacts via video observations from commercial traps at four common fishing sites in the DelMarVa region, 27-36 km off the coast, at depths of 20-30 m. Two traps within a 20 trap rig were customized by attaching GoPro® cameras to give views in front of the trap, toward the trap front, and to the rear of the trap. Analysis of 123 trap deployments shows that traps often drag across the ocean floor and habitats during the retrieval process. Duration of the dragging phase is strongly correlated with trap position on the line (r2=0.6; p<0.001); traps farther down the line drag significantly longer than traps closer to the boat and first retrieved (1st vs last trap: p<0.01). Dragging significantly increases trap-habitat interactions. Traps with minimal drag have <1% chance of contacting EFH but dragging increases the proportion of traps interacting with EFH to 46%. Observed trap-habitat interactions include: damaging and breaking coral, and running over sea stars, anemones, and bryozoans. Essential fish habitats located off the DelMarVa coast are highly fragmented and sparse, and adverse impacts of passive fishing gear probably affect a large portion of the available habitat.

Use of fish species from different trophic levels to control algae and water quality: An enclosure experiment in eutrophic area of Xiaojiang River.

PubMed

Hu, Lian; Yang, Zhi; Pan, Xiaojie; Zhao, Na; Peng, Jianhua; Wan, Chengyan

2017-01-01

The effects of stocking both filter-feeding fish and piscivorous fish were compared to the effects of stocking only filter-feeding fish for suppressing algal blooms and improving water quality in the impoundment area of Xiaojiang River where catfish were dominant. Using only filter-feeding fish for algal suppression and water quality control was more effective in the short-term, but use of both filter-feeding fish and piscivorous fish was better in the long-term. Obvious suppression of phytoplankton biomass (PB) only occurred during the first 14 days regardless of the fish stocked. Adding fish to the enclosure clearly alters phytoplankton community structure and introducing piscivorous fish to an enclosure stocked with filter-feeding fish changed the relative densities of dominant algae species. While stocking filter-feeding fish decreased total nitrogen concentration by removing phytoplankton, it did not effectively decrease total phosphorus and Chlorophyll a concentrations. Introducing piscivorous fish to the enclosure weakened the relationship between nutrients and phytoplankton. Results indicate that stocking only filter-feeding fish to improve water quality and suppress phytoplankton in an impoundment area is insufficient and other technologies and means should be applied simultaneously.

Feeding rates affect growth, intestinal digestive and absorptive capabilities and endocrine functions of juvenile blunt snout bream Megalobrama amblycephala.

PubMed

Xu, Chao; Li, Xiang-Fei; Tian, Hong-Yan; Jiang, Guang-Zhen; Liu, Wen-Bin

2016-04-01

This study aimed to investigate the optimal feeding rate for juvenile blunt snout bream (average initial weight 23.74 ± 0.09 g) based on the results on growth performance, intestinal digestive and absorptive capabilities and endocrine functions. A total of 840 fish were randomly distributed into 24 cages and fed a commercial feed at six feeding rates ranging from 2.0 to 7.0% body weight (BW)/day. The results indicated that weight gain rate increased significantly (P < 0.05) as feeding rates increased from 2.0 to 5.0% BW/day, but decreased with the further increasing feeding rates (P > 0.05). Protein efficiency ratio and nitrogen and energy retention all showed a similar trend. However, feed conversion ratio increased significantly (P < 0.05) with increasing feeding rates. Feeding rates have little effects (P > 0.05) on whole-body moisture, ash and protein contents, but significantly (P < 0.05) affect both lipid and energy contents with the highest values both observed in fish fed 4.0% BW/day. In addition, moderate ration sizes (2.0-4.0% BW/day) resulted in the enhanced activities of intestinal enzymes, including lipase, protease, Na(+), K(+)-ATPase, alkaline phosphatase and creatine kinase. Furthermore, the mRNA levels of growth hormone, insulin-like growth factors-I, growth hormone receptor and neuropeptide all increased significantly (P < 0.05) as feeding rates increased from 2.0 to 5.0% and 6.0% BW/day, but decreased significantly (P < 0.05) with the further increase in feeding rates, whereas both leptin and cholecystokinin expressions showed an opposite trend. Based on the broken-line regression analysis of SGR against feeding rates, the optimal feeding rate for juvenile blunt snout bream was estimated to be 4.57% BW/day.

Growth performance and plasma metabolites in juvenile Siberian sturgeon Acipenser baerii (Brandt, 1869) subjected to various feeding strategies at different sizes.

PubMed

Jafari, Naghmeh; Falahatkar, Bahram; Sajjadi, Mir Masoud

2018-06-16

The effect of various feeding strategies was evaluated on growth performance and biochemical parameters in two sizes of Siberian sturgeon (465.75 ± 11.18 and 250.40 ± 12 g) during 45 days. Fish were distributed into six experimental treatments including large fish with satiation feeding (LA), small fish with satiation feeding (SA), large fish with 50% satiation feeding (LR), small fish with 50% satiation feeding (SR), large starved fish (LS), and small starved fish (SS). Differences in final weight between LA and LR treatments were not noticeable, whereas SA and SR treatments showed significant differences. Growth parameters were more affected in small fish. In condition factor and weight gain in starved treatments, a considerable reduction occurred by interaction between feeding strategies and fish size, so the lowest values were obtained in SS treatment. Glucose levels significantly decreased in small fish during the starvation. Interaction between feeding strategy and fish size indicated the highest and lowest albumin level in SA and SS treatment, respectively. Cholesterol, triglyceride, total protein, and globulin showed no significant differences. It can be deduced that small fish are more sensitive to starvation than the large fish. Since glucose and albumin showed significant decrease in starved small fish, these parameters can help to monitor nutritional status and feeding practices. It was indicated that in both sizes of Siberian sturgeon, feeding 50% satiation reduced the food cost without negative impact on physiological condition, and it can be considered as an appropriate strategy to face unfavorable circumstances.

The Identification of Hunger Behaviour of Lates Calcarifer through the Integration of Image Processing Technique and Support Vector Machine

NASA Astrophysics Data System (ADS)

Taha, Z.; Razman, M. A. M.; Adnan, F. A.; Ghani, A. S. Abdul; Majeed, A. P. P. Abdul; Musa, R. M.; Sallehudin, M. F.; Mukai, Y.

2018-03-01

Fish Hunger behaviour is one of the important element in determining the fish feeding routine, especially for farmed fishes. Inaccurate feeding routines (under-feeding or over-feeding) lead the fishes to die and thus, reduces the total production of fishes. The excessive food which is not eaten by fish will be dissolved in the water and thus, reduce the water quality (oxygen quantity in the water will be reduced). The reduction of oxygen (water quality) leads the fish to die and in some cases, may lead to fish diseases. This study correlates Barramundi fish-school behaviour with hunger condition through the hybrid data integration of image processing technique. The behaviour is clustered with respect to the position of the centre of gravity of the school of fish prior feeding, during feeding and after feeding. The clustered fish behaviour is then classified by means of a machine learning technique namely Support vector machine (SVM). It has been shown from the study that the Fine Gaussian variation of SVM is able to provide a reasonably accurate classification of fish feeding behaviour with a classification accuracy of 79.7%. The proposed integration technique may increase the usefulness of the captured data and thus better differentiates the various behaviour of farmed fishes.

Fish and rapeseed oil consumption in infants and mothers: dietary habits and determinants in a nationwide sample in Germany.

PubMed

Stimming, Madlen; Mesch, Christina M; Kersting, Mathilde; Libuda, Lars

2015-10-01

Fish and rapeseed oil are major sources of omega-3 polyunsaturated fatty acids (n-3 PUFA) in complementary food, but little is known about current consumption in Germany. We conducted a nationwide consumer survey to assess the consumption habits of fish and rapeseed oil and their determining factors in 985 mother-child dyads in Germany. One-fourth of infants ate fish as often as recommended, i.e. at least once per week. Half of the mothers stated that they mainly used rapeseed oil for self-prepared and/or commercial vegetable-potato-meat meals. In contrast, mothers more frequently met recommendations for fish consumption (41 %), but used rapeseed oil (34 %) less often for their own nutrition. Maternal eating behaviour was the most important predictor for both of these n-3 PUFA rich foods in infants' nutrition. In contrast to infants' fish consumption, rapeseed oil intake in infancy was found to be influenced by some further factors, i.e. mothers' social class and omega-3 knowledge, which were also key determinants of mothers' own fish and rapeseed oil consumption. To promote fish with complementary feeding, programs should focus on families whose mothers rarely eat fish. Nutritional campaigns to improve omega-3 knowledge-especially focusing on lower social classes-could be effective in increasing rapeseed oil consumption, although these programs should be combined with environmental improvements as it has been already started through the use of rapeseed oil in commercial baby jars.

The classification of hunger behaviour of Lates Calcarifer through the integration of image processing technique and k-Nearest Neighbour learning algorithm

NASA Astrophysics Data System (ADS)

Taha, Z.; Razman, M. A. M.; Ghani, A. S. Abdul; Majeed, A. P. P. Abdul; Musa, R. M.; Adnan, F. A.; Sallehudin, M. F.; Mukai, Y.

2018-04-01

Fish Hunger behaviour is essential in determining the fish feeding routine, particularly for fish farmers. The inability to provide accurate feeding routines (under-feeding or over-feeding) may lead the death of the fish and consequently inhibits the quantity of the fish produced. Moreover, the excessive food that is not consumed by the fish will be dissolved in the water and accordingly reduce the water quality through the reduction of oxygen quantity. This problem also leads the death of the fish or even spur fish diseases. In the present study, a correlation of Barramundi fish-school behaviour with hunger condition through the hybrid data integration of image processing technique is established. The behaviour is clustered with respect to the position of the school size as well as the school density of the fish before feeding, during feeding and after feeding. The clustered fish behaviour is then classified through k-Nearest Neighbour (k-NN) learning algorithm. Three different variations of the algorithm namely cosine, cubic and weighted are assessed on its ability to classify the aforementioned fish hunger behaviour. It was found from the study that the weighted k-NN variation provides the best classification with an accuracy of 86.5%. Therefore, it could be concluded that the proposed integration technique may assist fish farmers in ascertaining fish feeding routine.

Trophic relationships of albatrosses associated with squid and large-mesh drift-net fisheries in the North Pacific Ocean

USGS Publications Warehouse

Gould, Patrick J.; Ostrom, Peggy H.; Walker, William

1997-01-01

The diets of Laysan (Diomedea immutabilis) and black-footed albatrosses (D. nigripes) killed in squid and large-mesh drift nets in the transitional zone of the North Pacific Ocean were investigated by examining the contents of the digestive tracts and determining δ13C and δ15N values in breast-muscle tissue. The results show that (i) the combined prey of the two species of albatross consists of over 46 species of marine organisms including coelenterates, arthropods, mollusks, fish, and marine mammals; (ii) both species supplement their traditional diets with food made available by commercial fishing operations (e.g., net-caught squid and offal); (iii) while obtained from drift nets, diets of nonbreeding Laysan and black-footed albatrosses are dominated by neon flying squid (Ommastrephes bartrami); (iv) in the absence of drift-net-related food, Laysan albatrosses feed most heavily on fish and black-footed albatrosses feed most heavily on squid; and (v) based on δ15N values, nonbreeding adult Laysan albatrosses from the transitional zone of the North Pacific Ocean and Laysan albatross nestlings fed by adults from Midway Island in the subtropical Pacific feed at one trophic level and one-third of a trophic level lower than black-footed albatrosses, respectively.

Specialized specialists and the narrow niche fallacy: a tale of scale-feeding fishes.

PubMed

Kolmann, Matthew A; Huie, Jonathan M; Evans, Kory; Summers, Adam P

2018-01-01

Although rare within the context of 30 000 species of extant fishes, scale-feeding as an ecological strategy has evolved repeatedly across the teleost tree of life. Scale-feeding (lepidophagous) fishes are diverse in terms of their ecology, behaviour, and specialized morphologies for grazing on scales and mucus of sympatric species. Despite this diversity, the underlying ontogenetic changes in functional and biomechanical properties of associated feeding morphologies in lepidophagous fishes are less understood. We examined the ontogeny of feeding mechanics in two evolutionary lineages of scale-feeding fishes: Roeboides , a characin, and Catoprion , a piranha. We compare these two scale-feeding taxa with their nearest, non-lepidophagous taxa to identify traits held in common among scale-feeding fishes. We use a combination of micro-computed tomography scanning and iodine staining to measure biomechanical predictors of feeding behaviour such as tooth shape, jaw lever mechanics and jaw musculature. We recover a stark contrast between the feeding morphology of scale-feeding and non-scale-feeding taxa, with lepidophagous fishes displaying some paedomorphic characters through to adulthood. Few traits are shared between lepidophagous characins and piranhas, except for their highly-modified, stout dentition. Given such variability in development, morphology and behaviour, ecological diversity within lepidophagous fishes has been underestimated.

Sudden weaning of angel fish pterophyllum scalare (Lichtenstein) (Pisces; Cichlidae) larvae from brine shrimp (Artemia sp) nauplii to formulated larval feed.

PubMed

Herath, Sandamali Sakunthala; Atapaththu, Kerthi Sri Senarathna

2013-12-01

This study investigated the effects of sudden weaning of angel fish larvae (Pteraphylum scalari) from Artemia nauplii to commercial larval feed. Four days post hatch (DPH) larvae were reared in four different weaning protocols (TR1-TR4) with triplicates in a complete randomize design. Larvae in TR1 and TR4 were exclusively fed Artemia nauplii and dry feed respectively. In TR2 and TR3, larvae were initially fed Artemia nauplii and suddenly wean to formulated feed on 14 DPH and 7 DPH respectively. The experiment was lasted for 28 days. At the end of the experiment, final mean weight (FW), total length (FL), height (FH), Daily Weight Gain (DWG), Specific Growth Rate (SGR), survival and stress index were compared. Significantly highest (P < 0.05) FW, DWG and SGR were observed in TR1 and TR2 while former values of TR3 were not significantly different from TR1. Highest FL observed in TR1 and TR2 while FL of TR2 was statistically similar to that of TR3. The poorest growth was observed in larvae solely fed formulated feed. Survival and the stress index were independent from weaning methods. Although sudden weaning is possible on 7 DPH, larvae showed comparatively higher growth when switch off to formulate feed on 14 DPH.

Residue depletion of oxytetracycline from fillet tissues of northern pike and walleye

USGS Publications Warehouse

Bernardy, J.A.; Vue, C.; Gaikowski, M.P.; Stehly, G.R.; Gingerich, W.H.; Moore, A.

2003-01-01

Iowa Department of Natural Resources Fisheries Bureau,Rathbun Research,15053 Hatchery Place,Moravia, IA 52571-8933,USA The broad-spectrum antibacterial drug oxytetracycline (OTC) is used in the U.S. to treat certain diseases in salmonids and catfish. This study was conducted to support an extension of the OTC label to include all cool-water fish species cultured at U.S. public aquaculture facilities by satisfying human food safety requirements. Juvenile northern pike (Esox lucius; mean weight: 117 g) and walleye (Stizostedion vitreum; mean weight: 59 g) were fed OTC-medicated diets near the maximum legal treatment rate (82.7 mg OTC-HCl/kg fish/day for 10 days) and near the lower limit of the water temperature range for most disease outbreaks in these species (14 and 16??C, respectively). Two trials were conducted simultaneously with northern pike, one using commercially medicated feed and the other using on-site OTC top-coated feed. A third trial was performed with walleye using on-site OTC top-coated feed. Fillet tissues were collected and OTC free base (OTC-base) concentrations were determined by high performance liquid chromatography. The maximum mean OTC-base concentrations in the fillet tissue were 319 ng/g in northern pike (skinless) and 721 ng/g in walleye (skin-on), both well below the current tolerance limit of 2000 ng/g OTC-base. The log-linear loss of OTC-base from the fillet tissues was monophasic, with terminal phase half-lives of 5.9 days in northern pike fed commercial medicated feed, 6.7 days in northern pike fed top-coated feed, and 10.5 days in walleye fed top-coated feed. The data supported a zero withdrawal time in juvenile northern pike and walleye fed OTC at the approved dose level for 10 days at water temperatures down to 14 and 16??C respectively. Published by Elsevier Science B.V.

Effect of The Phytase Enzyme Addition in The Artificial Feed on Digestibility of Feed, Feed Conversion Ratio and Growth of Gift Tilapia Saline Fish (Oreochromis niloticus) Nursery Stadia I

NASA Astrophysics Data System (ADS)

Rachmawati, Diana; Samidjan, Istiyanto; Elfitasari, Tita

2018-02-01

The purpose of this study was to determine the effect of adding the phytase enzyme in the artificial feed on digestibility of feed, feed conversion ratio and growth of gift tilapia saline fish (Oreochromis niloticus) nursery stadia I. The fish samples in this study used gift tilapia saline fish (O. niloticus) with an average weight of 0,62 ± 0,008 g/fish and the stocking density of 1 fish1 L. Experimental method used in this study was completely randomized design with 4 treatments and 3 repetitions. The treatments were by adding phytase enzyme in artificial feed with the different level of doses those were A (0 FTU kg1 feed), B (500 FTU kg1 feed), C (1000 FTU kg1 feed) and D (1500 FTU kg1 feed). The results show that the addition of phytase enzyme was significantly (P<0.01) affected on apparent digestibility coefficient of protein (ADCP), apparent digestibility coefficient of Phospor (ADCF), feed conversion ratio (FCR), protein efficiency ratio (PER), and relative growth rate (RGR), on the other hand it insignificantly (P>0.05) affected on Survival Rate (SR) of gift tilapia saline fish. The optimum doses of phytase enzyme on RGR, FCR, PER, ADCP and ADCF of gift tilapia saline fish ranged from 1060 to 1100 FTU kg-1 feed.

Marine Carotenoids: Biological Functions and Commercial Applications

PubMed Central

Vílchez, Carlos; Forján, Eduardo; Cuaresma, María; Bédmar, Francisco; Garbayo, Inés; Vega, José M.

2011-01-01

Carotenoids are the most common pigments in nature and are synthesized by all photosynthetic organisms and fungi. Carotenoids are considered key molecules for life. Light capture, photosynthesis photoprotection, excess light dissipation and quenching of singlet oxygen are among key biological functions of carotenoids relevant for life on earth. Biological properties of carotenoids allow for a wide range of commercial applications. Indeed, recent interest in the carotenoids has been mainly for their nutraceutical properties. A large number of scientific studies have confirmed the benefits of carotenoids to health and their use for this purpose is growing rapidly. In addition, carotenoids have traditionally been used in food and animal feed for their color properties. Carotenoids are also known to improve consumer perception of quality; an example is the addition of carotenoids to fish feed to impart color to farmed salmon. PMID:21556162

Stable isotopes in juvenile marine fishes and their invertebrate prey from the Thames Estuary, UK, and adjacent coastal regions

NASA Astrophysics Data System (ADS)

Leakey, Chris D. B.; Attrill, Martin J.; Jennings, Simon; Fitzsimons, Mark F.

2008-04-01

Estuaries are regarded as valuable nursery habitats for many commercially important marine fishes, potentially providing a thermal resource, refuge from predators and a source of abundant prey. Stable isotope analysis may be used to assess relative resource use from isotopically distinct sources. This study comprised two major components: (1) development of a spatial map and discriminant function model of stable isotope variation in selected invertebrate groups inhabiting the Thames Estuary and adjacent coastal regions; and (2) analysis of stable isotope signatures of juvenile bass ( Dicentrarchus labrax), sole ( Solea solea) and whiting ( Merlangius merlangus) for assessment of resource use and feeding strategies. The data were also used to consider anthropogenic enrichment of the estuary and potential energetic benefits of feeding in estuarine nursery habitat. Analysis of carbon (δ 13C), nitrogen (δ 15N) and sulphur (δ 34S) isotope data identified significant differences in the 'baseline' isotopic signatures between estuarine and coastal invertebrates, and discriminant function analysis allowed samples to be re-classified to estuarine and coastal regions with 98.8% accuracy. Using invertebrate signatures as source indicators, stable isotope data classified juvenile fishes to the region in which they fed. Feeding signals appear to reflect physiological (freshwater tolerance) and functional (mobility) differences between species. Juvenile sole were found to exist as two isotopically-discrete sub-populations, with no evidence of mixing between the two. An apparent energetic benefit of estuarine feeding was only found for sole.

Use of food waste, fish waste and food processing waste for China's aquaculture industry: Needs and challenge.

PubMed

Mo, Wing Yin; Man, Yu Bon; Wong, Ming Hung

2018-02-01

China's aquaculture industry is growing dramatically in recent years and now accounts for 60.5% of global aquaculture production. Fish protein is expected to play an important role in China's food security. Formulated feed has become the main diet of farmed fish. The species farmed have been diversified, and a large amount of 'trash fish' is directly used as feed or is processed into fishmeal for fish feed. The use of locally available food waste as an alternative protein source for producing fish feed has been suggested as a means of tackling the problem of sourcing safe and sustainable feed. This paper reviews the feasibility of using locally available waste materials, including fish waste, okara and food waste. Although the fishmeal derived from fish waste, okara or food waste is less nutritious than fishmeal from whole fish or soybean meal, most fish species farmed in China, such as tilapia and various Chinese carp, grow well on diets with minimal amounts of fishmeal and 40% digestible carbohydrate. It can be concluded that food waste is suitable as a component of the diet of farmed fish. However, it will be necessary to revise regulations on feed and feed ingredients to facilitate the use of food waste in the manufacture of fish feed. Copyright © 2017 Elsevier B.V. All rights reserved.

The effect of the addition of cow brain powder in commercial feed on the gonadal maturity of comet goldfish (Carassius auratus auratus)

NASA Astrophysics Data System (ADS)

Andriani, Y.; Subhan, U.; Rosidah; Iskandar; Zidni, I.; Abdillah, A. M.

2018-04-01

The aim of this research was to analysis the effect of addition bovine’s brain meal in artificial feed on gonad maturity and to find out the best time of gonad maturity in comet fish.This research was conducted at Fourth Building Hatchery Faculty of Fisheries and Marine Sciences Padjadjaran University on November 2014 until Januari 2015. Freeze drying of bovine brain was conducted at Research Center Inter University Bandung Institute of Technology. The research was using Completely Randomized Design (CRD) with four treatments and three replications.The treatment were 20 mg/kg, 35 mg/kg, 50mg/kg and control. The parameters of this research are Gonado Somatic Index (GSI) and egg maturity level. Addition of bovine brain meal in feed with the dose of 50 mg/kg are giving the best result until 45 days of the care time against gonad maturity of comet fish with GSI result 12.93 %, egg maturity level ripe phase 21.115 and fecundity 1520 grain/g.

The utilization of crude fish oil (CFO) to increase mudcrab (Scylla serrata) feed quality

NASA Astrophysics Data System (ADS)

Lamid, Mirni; Agustono

2017-02-01

Crude fish oil is one of essential fatty acid sources, which is found in Sardinella lemuru. This research aims to study the quality improvement of mudcrab(Scylla serrata) feed. Four feed formulations were designed by using completely randomized design, including P0 = trash fish + 1% tapioca starch; P1=trash fish + 2.0% crude fish oil + 1% tapioca starch;, P2= trash fish +4.0% crude fish oil + 1% tapioca starch; P3=trash fish + 6.0% crude fish oil + 1% tapioca starch; P4=trash fish +8.0% crude fish oil + 1% tapioca starch, respectively, which were carried out in quadruplicate. This study showed that feed formulation significantly affected crude protein, crude fiber, crude lipid, ash, organic matter and nitrogen free extract and energy of mudcrab. The P2 feed was the best formulation but had a slight different from P3 formulation.

Using industry ROV videos to assess fish associations with subsea pipelines

NASA Astrophysics Data System (ADS)

McLean, D. L.; Partridge, J. C.; Bond, T.; Birt, M. J.; Bornt, K. R.; Langlois, T. J.

2017-06-01

Remote Operated Vehicles are routinely used to undertake inspection and maintenance activities of underwater pipelines in north-west Australia. In doing so, many terabytes of geo-referenced underwater video are collected at depths, and on a scale usually unobtainable for ecological research. We assessed fish diversity and abundance from existing ROV videos collected along 2-3 km sections of two pipelines in north-west Australia, one at 60-80 m water depth and the other at 120-130 m. A total of 5962 individual fish from 92 species and 42 families were observed. Both pipelines were characterised by a high abundance of commercially important fishes including: snappers (Lutjanidae) and groupers (Epinephelidae). The presence of thousands of unidentifiable larval fish, in addition to juveniles, sub-adults and adults suggests that the pipelines may be enhancing, rather than simply attracting, fish stocks. The prevalence and high complexity of sponges on the shallower pipeline and of deepwater corals on the deeper pipeline had a strong positive correlation with the fish abundance. These habitats likely offer a significant food source and refuge for fish, but also for invertebrates upon which fish feed. A greater diversity on the shallower pipeline, and a higher abundance of fishes on both pipelines, were associated with unsupported pipeline sections (spans) and many species appeared to be utilising pipeline spans as refuges. This study is a first look at the potential value of subsea pipelines for fishes on the north-west shelf. While the results suggest that these sections of pipeline appear to offer significant habitat that supports diverse and important commercially fished species, further work, including off-pipeline surveys on the natural seafloor, are required to determine conclusively the ecological value of pipelines and thereby inform discussions regarding the ecological implications of pipeline decommissioning.

The Neuroendocrine Regulation of Food Intake in Fish: A Review of Current Knowledge

PubMed Central

Volkoff, Helene

2016-01-01

Fish are the most diversified group of vertebrates and, although progress has been made in the past years, only relatively few fish species have been examined to date, with regards to the endocrine regulation of feeding in fish. In fish, as in mammals, feeding behavior is ultimately regulated by central effectors within feeding centers of the brain, which receive and process information from endocrine signals from both brain and peripheral tissues. Although basic endocrine mechanisms regulating feeding appear to be conserved among vertebrates, major physiological differences between fish and mammals and the diversity of fish, in particular in regard to feeding habits, digestive tract anatomy and physiology, suggest the existence of fish- and species-specific regulating mechanisms. This review provides an overview of hormones known to regulate food intake in fish, emphasizing on major hormones and the main fish groups studied to date. PMID:27965528

Substitution of fish oil with camelina oil and inclusion of camelina meal in diets fed to Atlantic cod (Gadus morhua) and their effects on growth, tissue lipid classes, and fatty acids.

PubMed

Hixson, S M; Parrish, C C

2014-03-01

Developing a commercially relevant Atlantic cod aquaculture industry will require improvements in feed sustainability. Camelina oil and meal are potential replacements of fish oil and fish meal in aquaculture feeds. Camelina oil is high in 18:3ω3 (30%), with an ω3/ω6 ratio > 1. Camelina meal has a considerable crude protein level (38%), which includes significant amounts of methionine and phenylalanine. Four diets were tested; each diet was fed to triplicate tanks (3 tanks per diet) of Atlantic cod (14.4 g/fish; 70 fish per tank) for 13 wk. The diets included a fish oil/fish meal control (FO) and three diets which replaced 100% of fish oil with camelina oil: one diet contained fish meal (100CO), another solvent extracted fish meal (100COSEFM), and another had fish meal partially reduced by 15% inclusion of camelina meal (100CO15CM). Growth was measured (length and weight) and tissue samples were collected for lipid analysis (muscle, liver, brain, gut, spleen, skin, and carcass) at wk 0 (before feeding the experimental diet) and at wk 13. Cod fed camelina oil had a lower (P < 0.001) final weight than cod fed the FO diet (50.8 ± 10.3 g/fish). Cod fed 100CO15CM had a lower (P < 0.001) final weight (35.0 ± 8.0 g) than those fed 100CO (43.6 ± 8.9 g) and 100COSEFM (46.7 ± 10.7 g). Cod tissues in the 100COSEFM treatment were most impacted by dietary fatty acid profile. Multivariate statistics revealed that FO and 100COSEFM tissue fatty acid profiles were 21 to 31% different, depending on tissue type. The full replacement of fish oil with camelina oil, plus solvent extracted fish meal had an overarching effect on the entire fatty acid profile of the whole animal. Fatty acid mass balance calculations indicated that cod fed 100COSEFM elongated 13% of 18:3ω3 to 20:3ω3 and oxidized the remaining 87%, whereas cod fed fish oil showed a much lower (P < 0.001) elongation of 18:3ω3 of 1.6%. These results suggest that excess 18:3ω3 from camelina oil caused some fatty acid elongation, but little desaturation. Energy budget estimates indicated that cod fed 100COSEFM deposited the most energy throughout the trial (60 kJ/fish; P = 0.019), mostly in the liver (90%). Excess camelina lipids were not necessarily utilized for energy, which likely impacted growth. Feeding 100% camelina oil to Atlantic cod impacted growth and lipid and fatty acid composition; however, additional removal of fish oil from fish meal caused the greatest change in cod lipid composition and utilization.

The aquaculture potential of Tilapia rendalli in relation to its feeding habits and digestive capabilities

NASA Astrophysics Data System (ADS)

Hlophe, S. N.; Moyo, N. A. G.

Tilapia rendalli is a predominately macrophagous fish. However, it was able to colonise an oligotrophic dam (Flag Boshielo) with limited macrophytes. Therefore, the diet of T. rendalli in this dam was investigated; its stomach contents were examined over 12 months. A size related dietary shift was evident. Juveniles fed mainly on zooplankton while sub-adult and adult fish grazed on both macrophytes and marginal vegetation. T. rendalli’s ability to strive in an environment with limited food resources led to a subsequent study to determine its aquaculture potential. Its growth performance was compared to that of the commonly cultured Oreochromis mossambicus. Juveniles of both species were fed a commercial tilapia diet for 60 days. Specific growth rate and protein efficiency ratio was comparable to that of O. mossambicus (P > 0.05, ANOVA). Feed conversion ratio was significantly higher (P < 0.05) in T. rendalli (1.43) than in O. mossambicus (1.25) indicating a better efficiency in feed utilisation by O. mossambicus. At a physiological level, protease, lipase and cellulase activities did not differ significantly between the two fish species (P > 0.05). Amylase activities were significantly higher (P < 0.05) in T. rendalli than in O. mossambicus. The highest amylase activities were recorded in the proximal intestines as 26.34 and 22.00 μmol/min/mg protein in T. rendalli and O. mossambicus respectively. This may be an indicator that T. rendalli is better equipped to digest plant diets. T. rendalli may be the aquaculture species of choice for emerging fish farmers who cannot afford the highly priced fishmeal as a protein source in fish diets.

Lack of size selectivity for paddlefish captured in hobbled gillnets

USGS Publications Warehouse

Scholten, G.D.; Bettoli, P.W.

2007-01-01

A commercial fishery for paddlefish Polyodon spathula caviar exists in Kentucky Lake, a reservoir on the lower Tennessee River. A 152-mm (bar-measure) minimum mesh size restriction on entanglement gear was enacted in 2002 and the minimum size limit was increased to 864 mm eye-fork length to reduce the possibility of recruitment overfishing. Paddlefish were sampled in 2003-2004 using experimental monofilament gillnets with panels of 89, 102, 127, 152, 178, and 203-mm meshes and the efficacy of the mesh size restriction was evaluated. Following the standards of commercial gear used in that fishery, nets were "hobbled" (i.e., 128 m ?? 3.6 m nets were tied down to 2.4 m; 91 m ?? 9.1 m nets were tied down to 7.6 m). The mean lengths of paddlefish (Ntotal = 576 fish) captured in each mesh were similar among most meshes and bycatch rates of sublegal fish did not vary with mesh size. Selectivity curves could not be modeled because the mean and modal lengths of fish captured in each mesh did not increase with mesh size. Ratios of fish girth to mesh perimeter (G:P) for individual fish were often less than 1.0 as a result of the largest meshes capturing small paddlefish. It is unclear whether lack of size selectivity for paddlefish was because the gillnets were hobbled, the unique morphology of paddlefish, or the fact that they swim with their mouths agape when filter feeding. The lack of size selectivity by hobbled gillnets fished in Kentucky Lake means that managers cannot influence the size of paddlefish captured by commercial gillnet gear by changing minimum mesh size regulations. ?? 2006 Elsevier B.V. All rights reserved.

Exposure of juvenile Danio rerio to aged TiO₂ nanomaterial from sunscreen.

PubMed

Fouqueray, Manuela; Noury, Patrice; Dherret, Lysiane; Chaurand, Perrine; Abbaci, Khedidja; Labille, Jerome; Rose, Jerome; Garric, Jeanne

2013-05-01

The toxicity of dietary exposure to artificially aged TiO₂ nanomaterial (T-Lite) used in sunscreen cream was studied on Danio rerio. Embryolarval assays were conducted to assess the effects of TiO₂ residues of nanomaterial (RNM) on fish early life stages. Juvenile fishes were exposed by the trophic route in two experiments. During the first experiment, juvenile fishes were exposed to TiO₂ RNM for 14 days by adding RNM to commercial fish food. The second one consisted in producing a trophic food chain. Pseudokirchneriella subcapitata algae, previously contaminated with TiO₂ RNM in growth medium, was used to feed Daphnia magna neonates over a 48-h period. Daphnia were used next to feed juvenile fishes for 7 days. Accumulation of Ti, life traits (survival and growth) and biochemical parameters such as energy reserves, digestive (trypsin, esterase, cellulose and amylase) and antioxidant (superoxide dismutase and catalase) enzyme activity were measured at the end of exposures. As expected in the receiving aquatic system, TiO2 RNM at low concentrations caused a low impact on juvenile zebrafish. A slight impact on the early life stage of zebrafish with premature hatching was observed, and this effect appeared mainly indirect, due to possible embryo hypoxia. When juvenile fish are exposed to contaminated food, digestive enzyme activity indicated a negative effect of TiO₂ RNM. Digestive physiology was altered after 14 days of exposure and seemed to be an indirect target of TiO₂ RNM when provided by food.

Nutrition, feeding, and behavior of fish.

PubMed

Lall, Santosh P; Tibbetts, Sean M

2009-05-01

Nutrition and feeding influence growth, reproduction, and health of fish and their response to physiologic and environmental stressors and pathogens. The basics of fish metabolism are similar to those of warm-blooded animals in that they involve food intake, digestion, absorption, and transport of nutrients to the various tissues. Fish, however, being the most primitive form of vertebrates, possess some distinguishing features which will be discussed. Unlike warm-blooded animals, which are homoeothermic, fish are poikilothermic, so their body temperature and metabolic rate depends on the water temperature and this has practical implications for the nutrition, feeding and health of fish. Several behavioral responses have been linked to methods of feeding, feeding habits, frequency of feeding, mechanisms of food detection, and food preferences. Fish are also unique among vertebrates in their ability to absorb minerals not only from their diets but also from water through their gills and skin.

Comparative study on the gut microbiotas of four economically important Asian carp species.

PubMed

Li, Xinghao; Yu, Yuhe; Li, Chang; Yan, Qingyun

2018-05-07

Gut microbiota of four economically important Asian carp species (silver carp, Hypophthalmichthys molitrix; bighead carp, Hypophthalmichthys nobilis; grass carp, Ctenopharyngodon idella; common carp, Cyprinus carpio) were compared using 16S rRNA gene pyrosequencing. Analysis of more than 590,000 quality-filtered sequences obtained from the foregut, midgut and hindgut of these four carp species revealed high microbial diversity among the samples. The foregut samples of grass carp exhibited more than 1,600 operational taxonomy units (OTUs) and the highest alpha-diversity index, followed by the silver carp foregut and midgut. Proteobacteria, Firmicutes, Bacteroidetes and Fusobacteria were the predominant phyla regardless of fish species or gut type. Pairwise (weighted) UniFrac distance-based permutational multivariate analysis of variance with fish species as a factor produced significant association (P<0.01). The gut microbiotas of all four carp species harbored saccharolytic or proteolytic microbes, likely in response to the differences in their feeding habits. In addition, extensive variations were also observed even within the same fish species. Our results indicate that the gut microbiotas of Asian carp depend on the exact species, even when the different species were cohabiting in the same environment. This study provides some new insights into developing commercial fish feeds and improving existing aquaculture strategies.

Effects of ammonia stress, dietary linseed oil and Edwardsiella ictaluri challenge on juvenile darkbarbel catfish Pelteobagrus vachelli.

PubMed

Li, Ming; Yu, Na; Qin, Jian G; Li, Erchao; Du, Zhenyu; Chen, Liqiao

2014-05-01

A two-stage study was carried out to test the response of juvenile darkbarbel catfish Pelteobagrus vachelli to ammonia stress, dietary lipid and bacterial challenge. At stage 1, the catfish (0.99 ± 0.01 g) fed a commercial diet were exposed to 0.01 and 5.70 mg L(-1) total ammonia nitrogen in nine replicates for 14 days. At stage 2, all fish previously exposed to either low or high ammonia were separately transferred into low ammonia (<0.01 mg L(-1)), and divided into three feeding groups. Fish were then fed three levels of linseed oil (0, 2 and 4%) in triplicate for 46 days. Fish growth performance and immune response were low in high ammonia at stage 1. At stage 2, fish growth and immune response were not significantly different between fish previously exposed to low and high ammonia in all diets. Fish fed 4% linseed oil showed the greatest weight gain, feed efficiency ratio, red blood cells, hemoglobin and hematocrit, and achieved higher lysozyme activity, phagocytic index, respiratory burst and total immunoglobulin than fish fed 0% linseed oil, but did not differ from fish fed 2% linseed oil regardless of previous ammonia exposure. After 14-day infection of Edwardsiella ictaluri, cumulative mortality of fish previously exposed to low ammonia was lower than that of fish exposed to high ammonia in all diets. Cumulative mortality of fish fed 0% linseed oil was highest, but the antibody titer of fish fed 4% linseed oil was highest regardless of previous ammonia treatments. This study indicates that ammonia stress has a lasting effect even after ammonia is lowed, but the adverse effect on fish can be mitigated through manipulation of dietary oil inclusion, especially under the challenge of pathogenic bacteria. Copyright © 2014 Elsevier Ltd. All rights reserved.

Food of the Pacific white-sided dolphin, Lagenorhynchus obliquidens, Dall's porpoise, Phocoenoides dalli, and northern fur seal, Callorhinus ursinus, off California and Washington

USGS Publications Warehouse

Stroud, Richard K.; Fiscus, Clifford H.; Kajimura, Hiroshi

1981-01-01

Our knowledge of the feeding habits of the Pacific white-sided dolphin, Lagenorhynchus obliquidens, and the Dall's porpoise, Phocoenoides dalli, is based on examination of the stomach contents of stranded animals, animals accidentally taken in commercial fishing gear, those taken in the western Pacific commercial fishery, and animals that died during capture attempts. Of these only a few were normally feeding animals taken at sea, whose stomach contents were thoroughly examined. Fished and squids previously identified from stomachs of dolphins and porpoises by various investigators are listed in Table 1.This paper documents the stomach contents of 44 Pacific white-sided dolphin and 9 Dall's porpoise collected at sea off California and Washington. All animals were collected by the authors during pelagic fur seal studies with the exception of three dolphins which were collected by a staff biologist during whale research voyages off California. Comparisons of stomach contents are made between the Pacific white-sided dolphins, Dall's porpoise, and northern fur seal, Callorhinus ursinus, collected near the same locations and usually on the same day. Mention of the dolphin, porpoise , and seal in this paper refers to the above-named species unless noted otherwise.

Nannochloropsis oceania-derived defatted meal as an alternative to fishmeal in Atlantic salmon feeds

PubMed Central

Gong, Yangyang; Bjarnason, Fridrik; Vasanth, Ghana K.; Dahle, Dalia; Huntley, Mark; Kiron, Viswanath

2017-01-01

Defatted microalgal biomass derived from biorefinery can be potential feed ingredients for carnivorous fish. The present study investigated the growth, feed intake:gain and health parameters in Atlantic salmon fed for 84 days with defatted Nannochloropsis oceania as a fishmeal replacer. Fish fed feeds containing the algal biomass (at 10 and 20% inclusion, alga groups) were compared with groups that consumed alga-devoid feeds (control group). The fish that received 20% alga tended to have reduced weight gain and specific growth rate. Condition factor, feed conversion ratio and feed intake of this fish group were significantly different when compared with the control group. Hepatosomatic and viscerosomatic indices, whole body and fillet proximate composition were not affected by the dietary treatments. Digestibility of dry matter, protein, lipid, ash and energy, as well as retention of lipid and energy of the fish that received feed with 20% alga meal were also significantly different from those of the control group. Serum superoxide dismutase activity of the 10% alga-fed fish was significantly higher compared with the control fish. Although alga feeding did not cause any distal intestinal inflammation, the intestinal proteins that were altered upon feeding 20% algal meal might be pointing to systemic physiological disturbances. In conclusion, feeds with 20% alga had a negative effect on feed intake, FCR, lipid and energy retention and health of the fish. The defatted Nannochloropsis oceania can be used at modest inclusion levels, around 10%, without negative effects on the performance of Atlantic salmon. PMID:28704386

Nannochloropsis oceania-derived defatted meal as an alternative to fishmeal in Atlantic salmon feeds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sørensen, Mette; Gong, Yangyang; Bjarnason, Fridrik

Defatted microalgal biomass derived from biorefinery can be potential feed ingredients for carnivorous fish. The present study investigated the growth, feed intake:gain and health parameters in Atlantic salmon fed for 84 days with defatted Nannochloropsis oceania as a fishmeal replacer. Fish fed feeds containing the algal biomass (at 10 and 20% inclusion, alga groups) were compared with groups that consumed alga-devoid feeds (control group). The fish that received 20% alga tended to have reduced weight gain and specific growth rate. Condition factor, feed conversion ratio and feed intake of this fish group were significantly different when compared with the controlmore » group. Hepatosomatic and viscerosomatic indices, whole body and fillet proximate composition were not affected by the dietary treatments. Digestibility of dry matter, protein, lipid, ash and energy, as well as retention of lipid and energy of the fish that received feed with 20% alga meal were also significantly different from those of the control group. Serum superoxide dismutase activity of the 10% alga-fed fish was significantly higher compared with the control fish. Although alga feeding did not cause any distal intestinal inflammation, the intestinal proteins that were altered upon feeding 20% algal meal might be pointing to systemic physiological disturbances. In conclusion, feeds with 20% alga had a negative effect on feed intake, FCR, lipid and energy retention and health of the fish. Lastly, the defatted Nannochloropsis oceania can be used at modest inclusion levels, around 10%, without negative effects on the performance of Atlantic salmon.« less

Nannochloropsis oceania-derived defatted meal as an alternative to fishmeal in Atlantic salmon feeds

DOE PAGES

Sørensen, Mette; Gong, Yangyang; Bjarnason, Fridrik; ...

2017-07-13

Defatted microalgal biomass derived from biorefinery can be potential feed ingredients for carnivorous fish. The present study investigated the growth, feed intake:gain and health parameters in Atlantic salmon fed for 84 days with defatted Nannochloropsis oceania as a fishmeal replacer. Fish fed feeds containing the algal biomass (at 10 and 20% inclusion, alga groups) were compared with groups that consumed alga-devoid feeds (control group). The fish that received 20% alga tended to have reduced weight gain and specific growth rate. Condition factor, feed conversion ratio and feed intake of this fish group were significantly different when compared with the controlmore » group. Hepatosomatic and viscerosomatic indices, whole body and fillet proximate composition were not affected by the dietary treatments. Digestibility of dry matter, protein, lipid, ash and energy, as well as retention of lipid and energy of the fish that received feed with 20% alga meal were also significantly different from those of the control group. Serum superoxide dismutase activity of the 10% alga-fed fish was significantly higher compared with the control fish. Although alga feeding did not cause any distal intestinal inflammation, the intestinal proteins that were altered upon feeding 20% algal meal might be pointing to systemic physiological disturbances. In conclusion, feeds with 20% alga had a negative effect on feed intake, FCR, lipid and energy retention and health of the fish. Lastly, the defatted Nannochloropsis oceania can be used at modest inclusion levels, around 10%, without negative effects on the performance of Atlantic salmon.« less

Occurrence of plastic debris in the stomach of the invasive crab Eriocheir sinensis.

PubMed

Wójcik-Fudalewska, Dagmara; Normant-Saremba, Monika; Anastácio, Pedro

2016-12-15

The Chinese mitten crab is known as a pest causing damage to fishing gears and fish. On the other hand, this highly invasive species is considered a delicacy by Asian migrants and therefore commercially fished and sold in many countries. The ingestion of plastic by the Chinese mitten crab Eriocheir sinensis from the Baltic coastal waters (Poland) and the Tagus Estuary (Portugal) was studied based on stomach content analysis. As many as 13% of the 302 analysed males and females (38.07-89.07mm carapace width) from both regions, contained microplastic in the form of strands and balls. Most of them were transparent. Ingested plastic particles were identified as fragments of fishing gears. Contamination with plastic may have a negative impact on this species as well as on higher trophic levels feeding on crabs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Application of food waste based diets in polyculture of low trophic level fish: effects on fish growth, water quality and plankton density.

PubMed

Mo, Wing Yin; Cheng, Zhang; Choi, Wai Ming; Man, Yu Bon; Liu, Yihui; Wong, Ming Hung

2014-08-30

Food waste was collected from local hotels and fish feed pellets were produced for a 6 months long field feeding trial. Three types of fish feed pellets (control diet: Jinfeng® 613 formulated feed, contains mainly fish meal, plant product and fish oil; Diet A: food waste based diet without meat and 53% cereal; Diet B: food waste based diet with 25% meat and 28% cereal) were used in polyculture fish ponds to investigate the growth of fish (grass carp, bighead and mud carp), changes in water quality and plankton density. No significant differences in the levels of nitrogen and phosphorous compounds of water body were observed between 3 fish ponds after the half-year feeding trial, while pond receiving Diet A had the highest density of plankton. The food waste combination of Diet B seems to be a better formulation in terms of the overall performance on fish growth. Copyright © 2014. Published by Elsevier Ltd.

Potential Contribution of Fish Feed and Phytoplankton to the Content of Volatile Terpenes in Cultured Pangasius (Pangasianodon hypophthalmus) and Tilapia (Oreochromis niloticus).

PubMed

Podduturi, Raju; Petersen, Mikael A; Mahmud, Sultan; Rahman, Md Mizanur; Jørgensen, Niels O G

2017-05-10

Geosmin and 2-methylisoborneol are the most recognized off-flavors in freshwater fish, but terpenes may also contribute off-flavor in fish. We identified six monoterpenes, 11 sesquiterpenes, and three terpene-related compounds in pangasius and tilapia from aquaculture farms in Bangladesh. The concentrations of most of the volatiles were below published odor thresholds, except for α-pinene, limonene, β-caryophyllene, α-humulene, and β-ionone in tilapia, and limonene and β-ionone in pangasius. To identify sources of the terpenes, terpene profiles of fish feed and phytoplankton in the ponds were analyzed. In feed and mustard cake (feed ingredient), five monoterpenes and two sesquiterpenes were identified, and five of these compounds were also detected in the fish. In phytoplankton, 11 monoterpenes were found and three also occurred in the fish. The higher number of terpenes common to both fish and feed, than to fish and phytoplankton, suggests that feed was a more abundant source of odor-active terpenes in the fish than phytoplankton.

Food Selectivity and Diet Switch Can Explain the Slow Feeding of Herbivorous Coral-Reef Fishes during the Morning

PubMed Central

Khait, Ruth; Obolski, Uri; Hadany, Lilach; Genin, Amatzia

2013-01-01

Most herbivorous coral-reef fishes feed slower in the morning than in the afternoon. Given the typical scarcity of algae in coral reefs, this behavior seems maladaptive. Here we suggest that the fishes' slow feeding during the morning is an outcome of highly selective feeding on scarcely found green algae. The rarity of the food requires longer search time and extended swimming tracks, resulting in lower bite rates. According to our findings by noon the fish seem to stop their search and switch to indiscriminative consumption of benthic algae, resulting in apparent higher feeding rates. The abundance of the rare preferable algae gradually declines from morning to noon and seems to reach its lowest levels around the switch time. Using in situ experiments we found that the feeding pattern is flexible, with the fish exhibiting fast feeding rates when presented with ample supply of preferable algae, regardless of the time of day. Analyses of the fish's esophagus content corroborated our conclusion that their feeding was highly selective in the morning and non-selective in the afternoon. Modeling of the fishes' behavior predicted that the fish should perform a diel diet shift when the preferred food is relatively rare, a situation common in most coral reefs found in a warm, oligotrophic ocean. PMID:24358178

Food selectivity and diet switch can explain the slow feeding of herbivorous coral-reef fishes during the morning.

PubMed

Khait, Ruth; Obolski, Uri; Hadany, Lilach; Genin, Amatzia

2013-01-01

Most herbivorous coral-reef fishes feed slower in the morning than in the afternoon. Given the typical scarcity of algae in coral reefs, this behavior seems maladaptive. Here we suggest that the fishes' slow feeding during the morning is an outcome of highly selective feeding on scarcely found green algae. The rarity of the food requires longer search time and extended swimming tracks, resulting in lower bite rates. According to our findings by noon the fish seem to stop their search and switch to indiscriminative consumption of benthic algae, resulting in apparent higher feeding rates. The abundance of the rare preferable algae gradually declines from morning to noon and seems to reach its lowest levels around the switch time. Using in situ experiments we found that the feeding pattern is flexible, with the fish exhibiting fast feeding rates when presented with ample supply of preferable algae, regardless of the time of day. Analyses of the fish's esophagus content corroborated our conclusion that their feeding was highly selective in the morning and non-selective in the afternoon. Modeling of the fishes' behavior predicted that the fish should perform a diel diet shift when the preferred food is relatively rare, a situation common in most coral reefs found in a warm, oligotrophic ocean.

Evaluation of an alternative to feeding whole frozen fish in belugas (Delphinapterus leucas).

PubMed

Mazzaro, Lisa M; Richmond, Julie P; Morgan, Jessica N; Kluever, Michaela E; Dunn, J Lawrence; Romano, Tracy A; Zinn, Steven A; Koutsos, Elizabeth A

2011-01-01

Feeding fish to captive piscivores can be challenging owing to cost, availability, variability in nutrient, and caloric composition, as well as handling and storage concerns. This trial evaluated the response of three belugas to being fed Fish Analog, an alternative to frozen fish. Body condition, gut transit time, serum chemistry and metabolic hormone analytes, immune function, and behavioral motivation were the dependent variables. Belugas (n=3) were fed various levels of Fish Analog (0-50%) over a 6-month period, and follow-up studies were conducted to further examine several dependent variables. When provided in gradually increasing amounts, belugas consumed the Fish Analog, with only minor fecal consistency changes and without behavioral responses indicative of gastric discomfort. Axillary girth and blubber thickness were positively correlated, and did not differ significantly with changes in the percentage of Fish Analog fed. Individual animal variation in initial passage time, some serum chemistry analytes, and immune function differences were noted following feeding of Fish Analog. Feeding Fish Analog reduced blood n9 fatty acids compared with captive belugas fed no Fish Analog. Feeding a DHA-enriched Fish Analog increased several n3 fatty acids, including eicosapentaenoic acid, but not DHA, compared with whales fed no Fish Analog or non-DHA-enriched Fish Analog. Fish Analog was shown to be a viable alternative to feeding fish at up to 50% of the dietary caloric density. © 2010 Wiley-Liss, Inc.

n3- polyunsaturated Fat Acid Content of Some Edible Fish from Bahrain Waters

NASA Astrophysics Data System (ADS)

Al-Arrayedu, F. H.; Al Maskati, H. A.; Abdullah, F. J.

1999-08-01

This study was performed to determine the content of n3- polyunsaturated fatty acids in 10 fish species that are commonly consumed in Bahrain in addition to the main commercial shrimp species. White sardinella, which is a plankton feeder, had the highest content of n3- polyunsaturated fatty acids. It had the highest value of eicosapentaenoic acid (146.5 ± 20 mg 100 g-1) and linolenic acid (98.9±f 100 g-1) and the second highest value of docosahexaenoic acid at (133.7 ± 22 mg 100 g-1). Spanish mackerel which feeds mainly on sardinella was second with eicosapentaenoc acid at 55 ± 5.4 mg 100 g-1, docosahexaenoic acid at 161 ± 19.8 mg 100 g-1, linolenic acid at 16.4 mg 100 g-1 and docosapentaenoic acid at 25 ± 1.9 mg 100 g-1. Rabbitfish, the most popular edible fish in Bahrain which feeds mainly on benthic algae had the third highest content of n3- polyunsaturated fatty acids with eicosapentaenoic acid at 37.5 ± 3.9 mg 100 g-1, docosahexaenoic acid at 76 ± 6.7 mg 100 g-1, and docosapentaenoic acid at 85.8 ± 10 mg 100 g-1. The other fish and crustacean species studied were Arabian carpet shark, doublebar bream, grouper, gray grunt, golden travally, keeled mullet, spangled emperor and shrimp. The study explores the transfer of n3- polyunsaturated fatty acids through the food webs of the examined fish. It is apparent, generally, that plankton feeders displayed the highest content of n3- polyunsaturated fatty acids followed by seaweed and algae grazers, with benthic carnivores feeding on invertebrates displaying the poorest content. The values reported here, however, are much lower than those reported for fish available in American markets and in Mediterranean fish. Warm water temperature and high salinity which lead to lowering of the density of phytoplankton and phytoplankton content of n3- polyunsaturated fatty acids are suggested as the reason for the observed low values of n3- polyunsaturated fatty acids in Bahrain fish.

An examination of the intestinal tract of Atlantic salmon, Salmo salar L., parr fed different varieties of soy and maize.

PubMed

Sanden, M; Berntssen, M H G; Krogdahl, A; Hemre, G-I; Bakke-McKellep, A-M

2005-06-01

This study was conducted to investigate the long-term effects of feeding plant products from both traditional breeding and from biotechnology on intestinal somatic indices, histology and cell proliferation in first-feeding Atlantic salmon, Salmo salar L. (initial weight 0.21 +/- 0.02 g). A standard fishmeal diet (standard fishmeal) was formulated to contain fishmeal as the sole protein source and suprex maize as the main starch source. Six experimental diets were then developed: two in which some of the fishmeal was replaced with commercially available, genetically modified Roundup Ready full-fat soybean meal (GM-soy) or commercially available, non-GM full-fat soybean meal (nGM-soy) at a level of 12.5% of the total diet, and four diets in which the suprex maize was replaced with two lines of GM-maize (Dekalb 1; D1 and Pioneer 1; P1), both products of event MON810, and their half-sibling non-GM counterparts (Dekalb 2; D2 and Pioneer 2; P2), at a level of 12.1% of total diet. Each diet was fed to fish in triplicate tanks and the experiment lasted for 8 months, during which the fish reached a final weight of 101-116 g. There was no significant effect of diet on the intestinal indices, nor were histological changes observed in the pyloric caeca or mid intestine. In the distal intestine, one of nine sampled fish fed nGM-soy showed moderate changes, two of nine sampled fish fed GM-soy showed changes, one with moderate and one with severe changes, and two of nine fish fed nGM-maize D2 had moderate changes. Using a monoclonal antibody against proliferating cell nuclear antigen (PCNA), cell proliferative responses to the experimental diets were assessed. In fish fed both soy diets, a significantly higher (P < 0.05) cell proliferation response was observed in the distal intestine concomitant with an increased localization of PCNA positive cells along the whole distal intestinal folds. The PCNA response among the nGM-soy group was significantly higher compared with all the other diet groups. In contrast, for fish exposed to dietary maize (type D) compared with fish fed the standard fishmeal, the soy-diets (GM-soy and nGM-soy) and maize (type P), a significantly lower (P < 0.05) cell proliferation response was observed in the distal intestine. Results indicated that the GM plant products investigated in this study, at about 12% inclusion level, were as safe as commercially available non-GM products, at least in terms of their effect on indices and histological parameters of the Atlantic salmon intestinal tract.

Selection of diet for culture of juvenile silver pomfret, Pampus argenteus

NASA Astrophysics Data System (ADS)

Peng, Shiming; Shi, Zhaohong; Yin, Fei; Sun, Peng; Wang, Jiangang

2012-03-01

Juvenile silver pomfret, Pampus argenteus, was grown in culture tanks for 9 weeks on four different diets, and their effects on fish growth, digestive enzyme activity, and body composition were assessed. The feeding regime was as follows: Diet 1: fish meat; Diet 2: fish meat+artificial feed; Diet 3: fish meat+artificial feed+Agamaki clam meat; Diet 4: fish meat+artificial feed+Agamaki clam+copepods. The greatest weight gain was associated with Diet 4, while the lowest weight gain was associated with Diet 1. No significant difference was observed in weight gain between fish receiving Diet 2 and Diet 3. Specific growth rate followed similar trends as weight gain. The feed conversion ratio (FCR) of fish fed Diet 1 was significantly higher than the other fish groups, but no significant differences were observed in FCRs of fish fed Diet 2, Diet 3 or Diet 4. There was also no significant difference in the hepatosomatic index (HSI) between the four diets. For fish that received Diets 2-4, containing artificial feed, higher protease activities were detected. A higher lipid content of the experimental diets also significantly increased lipase activities and body lipid content. No significant differences in amylase activity or body protein content were found between Diets 1-4. In conclusion, a variety of food components, including copepods and artificial feed, in the diet of silver pomfret significantly increased digestive enzyme activity and could improve growth performance.

Ecosystem consequences of fish parasites

USGS Publications Warehouse

Lafferty, Kevin D.

2008-01-01

In most aquatic ecosystems, fishes are hosts to parasites and, sometimes, these parasites can affect fish biology. Some of the most dramatic cases occur when fishes are intermediate hosts for larval parasites. For example, fishes in southern California estuaries are host to many parasites. The most common of these parasites, Euhaplorchis californiensis, infects the brain of the killifish Fundulus parvipinnis and alters its behaviour, making the fish 10–30 times more susceptible to predation by the birds that serve as its definitive host. Parasites like E. californiensis are embedded in food webs because they require trophic transmission. In the Carpinteria Salt Marsh estuarine food web, parasites dominate the links and comprise substantial amount of biomass. Adding parasites to food webs alters important network statistics such as connectance and nestedness. Furthermore, some free-living stages of parasites are food items for free-living species. For instance, fishes feed on trematode cercariae. Being embedded in food webs makes parasites sensitive to changes in the environment. In particular, fishing and environmental disturbance, by reducing fish populations, may reduce parasite populations. Indirect evidence suggests a decrease in parasites in commercially fished species over the past three decades. In addition, environmental degradation can affect fish parasites. For these reasons, parasites in fishes may serve as indicators of environmental impacts.

Fish consumption and track to a fish feed formulation

NASA Astrophysics Data System (ADS)

Cai-Juan, Soong; Ramli, Razamin; Rahman, Rosshairy Abdul

2015-12-01

Strategically located in the equator, Malaysia is blessed with plenty of fish supply. The high demand in fish consumption has helped the development in the fishery industry and provided numerous jobs in the secondary sector, contributing significantly to the nation's income. A survey was conducted to understand the trend of current demands for fish for the purpose of designing a feed formulation, which is still limited in this area of study. Results showed that grouper fish in restaurants commanded a very high price compared to other species of fish. Tiger grouper gained the highest demand in most restaurants, while giant grouper had the highest price in restaurants. Due to the demand and challenges to culture this type of fish, a framework for fish feed formulation is proposed. The formulation framework when materialized could be an alternative to the use of trash fish as the feed for grouper.

Chemical contaminants in fish feeds used in federal salmonid hatcheries in the USA

USGS Publications Warehouse

Maule, A.G.; Gannam, A.L.; Davis, J.W.

2007-01-01

Recent studies have demonstrated that fish feeds contain significant concentrations of contaminants, many of which can bioaccumulate and bioconcentrate in fish. Organochlorine (OC) contaminants are present in the fish oils and fish meals used in feed manufacture, and some researchers speculate that all fish feeds contain measurable levels of some contaminants. To determine the concentration of contaminants in feeds used in US Fish and Wildlife Service's National Fish Hatcheries, we systematically collected samples of feed from 11 cold-water fish hatcheries. All samples (collected from October 2001 to October 2003) contained at least one polychlorinated dibenzo-p-dioxin (PCDD), polychlorinated dibenzofuran (PCDF), polychlorinated biphenyl (PCB) congener, or dichlorodiphenyltrichloroethane (DDT) metabolite. Of the 55 samples in which they were analyzed 39 contained PCDDs, 24 contained PCDFs and 24 contained DDT or its metabolites. There were 10- to 150-fold differences in concentrations of total PCBs, PCDDs, PCDFs and DDT. Although PCBs were the most commonly detected contaminant in our study, concentrations (range: 0.07-10.46 ng g-1 wet weight) were low compared to those reported previously. In general, we also found lower levels of OCs than reported previously in fish feed. Perhaps most notable was the near absence of OC pesticides - except for DDT or its metabolites, and two samples containing hexachlorocyclohexane (HCH). While contaminant concentrations were generally low, the ecological impacts can not be determined without a measure of the bioaccumulation of these compounds in the fish and the fate of these compounds after the fish are released. ?? 2006 Elsevier Ltd. All rights reserved.

The Positive Impact of the Early-Feeding of a Plant-Based Diet on Its Future Acceptance and Utilisation in Rainbow Trout

PubMed Central

Geurden, Inge; Borchert, Peter; Balasubramanian, Mukundh N.; Schrama, Johan W.; Dupont-Nivet, Mathilde; Quillet, Edwige; Kaushik, Sadasivam J.; Panserat, Stéphane; Médale, Françoise

2013-01-01

Sustainable aquaculture, which entails proportional replacement of fish-based feed sources by plant-based ingredients, is impeded by the poor growth response frequently seen in fish fed high levels of plant ingredients. This study explores the potential to improve, by means of early nutritional exposure, the growth of fish fed plant-based feed. Rainbow trout swim-up fry were fed for 3 weeks either a plant-based diet (diet V, V-fish) or a diet containing fishmeal and fish oil as protein and fat source (diet M, M-fish). After this 3-wk nutritional history period, all V- or M-fish received diet M for a 7-month intermediate growth phase. Both groups were then challenged by feeding diet V for 25 days during which voluntary feed intake, growth, and nutrient utilisation were monitored (V-challenge). Three isogenic rainbow trout lines were used for evaluating possible family effects. The results of the V-challenge showed a 42% higher growth rate (P = 0.002) and 30% higher feed intake (P = 0.005) in fish of nutritional history V compared to M (averaged over the three families). Besides the effects on feed intake, V-fish utilized diet V more efficiently than M-fish, as reflected by the on average 18% higher feed efficiency (P = 0.003). We noted a significant family effect for the above parameters (P<0.001), but the nutritional history effect was consistent for all three families (no interaction effect, P>0.05). In summary, our study shows that an early short-term exposure of rainbow trout fry to a plant-based diet improves acceptance and utilization of the same diet when given at later life stages. This positive response is encouraging as a potential strategy to improve the use of plant-based feed in fish, of interest in the field of fish farming and animal nutrition in general. Future work needs to determine the persistency of this positive early feeding effect and the underlying mechanisms. PMID:24386155

46 CFR 105.10-25 - Commercial fishing vessel.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Commercial fishing vessel. 105.10-25 Section 105.10-25... COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Definition of Terms Used in This Part § 105.10-25 Commercial fishing vessel. (a) The term commercial fishing vessel includes fishing vessels, cannery tenders...

46 CFR 105.10-25 - Commercial fishing vessel.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Commercial fishing vessel. 105.10-25 Section 105.10-25... COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Definition of Terms Used in This Part § 105.10-25 Commercial fishing vessel. (a) The term commercial fishing vessel includes fishing vessels, cannery tenders...

46 CFR 105.10-25 - Commercial fishing vessel.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Commercial fishing vessel. 105.10-25 Section 105.10-25... COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Definition of Terms Used in This Part § 105.10-25 Commercial fishing vessel. (a) The term commercial fishing vessel includes fishing vessels, cannery tenders...

46 CFR 105.10-25 - Commercial fishing vessel.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Commercial fishing vessel. 105.10-25 Section 105.10-25... COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Definition of Terms Used in This Part § 105.10-25 Commercial fishing vessel. (a) The term commercial fishing vessel includes fishing vessels, cannery tenders...

46 CFR 105.10-25 - Commercial fishing vessel.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Commercial fishing vessel. 105.10-25 Section 105.10-25... COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Definition of Terms Used in This Part § 105.10-25 Commercial fishing vessel. (a) The term commercial fishing vessel includes fishing vessels, cannery tenders...

Element levels in cultured and wild sea bass (Dicentrarchus labrax) and gilthead sea bream (Sparus aurata) from the Adriatic Sea and potential risk assessment.

PubMed

Zvab Rožič, Petra; Dolenec, Tadej; Baždarić, Branimir; Karamarko, Vatroslav; Kniewald, Goran; Dolenec, Matej

2014-02-01

In this study, the role of aquaculture activity as a source of selected metals was analyzed. Significant differences in element content between cultured (Dicentrarchus labrax, Sparus aurata) and wild fishes as well as between fish muscle and their feed were detected. Higher concentrations of trace elements (i.e., As, Cu, Hg, Se) in wild fish tissues in comparison with cultured ones indicate additional sources of metals beside fish feed as natural and/or anthropogenic sources. Generally, mean Cd, Cu, Pb, Se, and Zn concentrations in cultured (0.016, 1.79, 0.14, 0.87, and 34.32 μg/g, respectively) and wild (0.011, 1.97, 0.10, 1.78, and 23,54 μg/g, respectively) fish samples were below the permissible levels, while mean As (2.57 μg/g in cultured, 4.77 μg/g in wild) and Cr (5.25 μg/g in cultured, 2.92 μg/g in wild) values exceeded those limits. Hg values were lower in cultured (0.17 μg/g) and higher in wild (1.04 μg/g) fish specimens. The highest elemental concentrations were observed in almost all fish samples from Korčula sampling site. The smallest cultured sea basses showed As (4.01 μg/g), Cr (49.10 μg/g), Pb (0.65 μg/g), and Zn (136 μg/g) concentrations above the recommended limits; however, values decreased as fish size increased. Therefore, the majority of metal concentrations in commercial fishes showed no problems for human consumption. Also calculated Se:Hg molar ratios (all >1) and selenium health benefit values (Se-HBVs) (all positive) showed that consumption of all observed fishes in human nutrition is not risk.

Development and validation of a high performance liquid chromatography assay for 17alpha-methyltestosterone in fish feed.

PubMed

Marwah, Ashok; Marwah, Padma; Lardy, Henry

2005-09-25

17alpha-Methyltestosterone (MT) is used to manipulate the gender of a variety of fish species. A high performance liquid chromatography (HPLC) internal standard method for the determination of 17alpha-methyltestosterone in fish feed using 3beta-methoxy-17beta-hydroxyandrost-5-en-7-one as internal standard (IS) has been developed. The method has been validated for the quantitation of MT in fish feed using 245 nm UV absorbance as the parent wavelength and 255 nm as a qualifier wavelength. The method was validated in the concentration range of 15.0-120 mg/kg of 17alpha-methyltestosterone in fish feed. Method was also found to be suitable for other feeds.

Helminth communities of four commercially important fish species from Chetumal Bay, Mexico.

PubMed

Aguirre-Macedo, M L; Vidal-Martínez, V M; González-Solís, D; Caballero, P I

2007-03-01

The relative importance of ecology and evolution as factors determining species richness and composition of the helminth communities of fish is a matter of current debate. Theoretical studies use host-parasite lists, but these do not include studies on a temporal or spatial scale. Local environmental conditions and host biological characteristics are shown to influence helminth species richness and composition in four fish species (Eugerres plumieri, Hexanematichthys assimilis, Oligoplites saurus, and Scomberomorus maculatus) in Chetumal Bay, Mexico. With the exception of H. assimilis, the helminth communities had not been previously studied and possible associations between environmental and host biological characteristics as factors determining helminth species richness and composition using redundancy analysis (RDA) are described. Thirty-four helminth species are identified, with the highest number of species (19 total (mean = 6.3 +/- 2.1)) and the lowest (9 (4.0 +/- 1.0)) occurring in H. assimilis and S. maculatus, respectively. The larval nematodes Contracaecum sp. and Pseudoterranova sp. were not only the helminth species shared by all four host species but also were the most prevalent and abundant. Statistical associations between helminth community parameters and local ecological variables such as host habitat use, feeding habits, mobility, and time of residence in coastal lagoons are identified. Phylogeny is important because it clearly separates all four host species by their specialist parasites, although specific habitat and feeding habits also significantly influence the differentiation between the four fish species.

Generalist feeding strategies in Arctic freshwater fish: A mechanism for dealing with extreme environments

USGS Publications Warehouse

Laske, Sarah M.; Rosenberger, Amanda E.; Wipfli, Mark S.; Zimmerman, Christian E.

2018-01-01

Generalist feeding strategies are favoured in stressful or variable environments where flexibility in ecological traits is beneficial. Species that feed across multiple habitat types and trophic levels may impart stability on food webs through the use of readily available, alternative energy pools. In lakes, generalist fish species may take advantage of spatially and temporally variable prey by consuming both benthic and pelagic prey to meet their energy demands. Using stomach content and stable isotope analyses, we examined the feeding habits of fish species in Alaska's Arctic Coastal Plain (ACP) lakes to determine the prevalence of generalist feeding strategies as a mechanism for persistence in extreme environments (e.g. low productivity, extreme cold and short growing season). Generalist and flexible feeding strategies were evident in five common fish species. Fish fed on benthic and pelagic (or nektonic) prey and across trophic levels. Three species were clearly omnivorous, feeding on fish and their shared invertebrate prey. Dietary differences based on stomach content analysis often exceeded 70%, and overlap in dietary niches based on shared isotopic space varied from zero to 40%. Metrics of community‐wide trophic structure varied with the number and identity of species involved and on the dietary overlap and niche size of individual fishes. Accumulation of energy from shared carbon sources by Arctic fishes creates redundancy in food webs, increasing likely resistance to perturbations or stochastic events. Therefore, the generalist and omnivorous feeding strategies employed by ACP fish may maintain energy flow and food web stability in extreme environments.

Sources and fate of antimicrobials in integrated fish-pig and non-integrated tilapia farms.

PubMed

Li, Kang; Liu, Liping; Zhan, Jia; Scippo, Marie-Louise; Hvidtfeldt, Kristian; Liu, Yuan; Dalsgaard, Anders

2017-10-01

Antimicrobial contamination in aquaculture products constitutes a food safety hazard, but little is known about the introduction and accumulation of antimicrobials in integrated fish-pig aquaculture. This study, conducted in 2013, aimed to determine the residues of 11 types of antimicrobials by UPLC-MS/MS analysis in fish feed (n=37), pig feed (n=9), pig manure (n=9), pond sediment (n=20), fish skin (n=20) and muscle tissue (n=20) sampled from integrated tilapia-pig farms, non-integrated tilapia farms and fish feed supply shops. There was a higher occurrence of antimicrobial residues in fish skin from both integrated and non-integrated farms, and in pig manure. Enrofloxacin (3.9-129.3μg/kg) and sulfadiazine (0.7-7.8μg/kg) were commonly detected in fish skin and muscle, pig manure and pond sediment from integrated farms, with different types of antimicrobials found in pig manure and tilapia samples. In non-integrated farms, sulfadiazine (2.5-89.9μg/kg) was the predominant antimicrobial detected in fish skin and muscle, fish feed and pond sediment. In general, antimicrobials seemed not to be commonly transmitted from pig to fish in tilapia-pig integrated farms, and fish feed, pig feed and pond sediment did not seem as important sources of the antimicrobials found in fish from both systems. The frequent findings of antimicrobial residues in fish skin compared with fish muscle was probably due to different pharmacokinetics in different tissue types, which have practical food safety implications since antimicrobial residues monitoring is usually performed analyzing mixed skin and fish muscle samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Dietary fatty acids and inflammation in the vertebral column of Atlantic salmon, Salmo salar L., smolts: a possible link to spinal deformities.

PubMed

Gil Martens, L; Lock, E J; Fjelldal, P G; Wargelius, A; Araujo, P; Torstensen, B E; Witten, P E; Hansen, T; Waagbø, R; Ørnsrud, R

2010-12-01

Vegetable oils (Vo) are an alternative to fish oil (Fo) in aquaculture feeds. This study aimed to evaluate the effect of dietary soybean oil (Vo diet), rich in linoleic acid, and of dietary fish oil (Fo diet) on the development of spinal deformities under bacterial lipopolysaccharide (LPS)-induced chronic inflammation conditions in Atlantic salmon, Salmo salar L. Fish [25 g body weight (BW)] were fed the experimental diets for 99 days. On day 47 of feeding (40 g BW), fish were subjected to four experimental regimes: (i) intramuscular injections with LPS, (ii) sham-injected phosphate-buffered saline (PBS), (iii) intraperitoneally injected commercial oil adjuvant vaccine, or (iv) no treatment. The fish continued under a common feeding regime in sea water for 165 more days. Body weight was temporarily higher in the Vo group than in the Fo group prior to immunization and was also affected by the type of immunization. At the end of the trial, no differences were seen between the dietary groups. The overall prevalence of spinal deformities was approximately 14% at the end of the experiment. The Vo diet affected vertebral shape but did not induce spinal deformities. In groups injected with LPS and PBS, spinal deformities ranged between 21% and 38%, diet independent. Deformed vertebrae were located at or in proximity to the injection point. Assessment of inflammatory markers revealed high levels of plasma prostaglandin E₂ (PGE₂) in the Vo-fed and LPS-injected groups, suggesting an inflammatory response to LPS. Cyclooxigenase 2 (COX-2) mRNA expression in bone was higher in fish fed Fo compared to Vo-fed fish. Gene expression of immunoglobulin M (IgM) was up-regulated in bone of all LPS-injected groups irrespective of dietary oil. In conclusion, the study suggests that Vo is not a risk factor for the development of inflammation-related spinal deformities. At the same time, we found evidence that localized injection-related processes could trigger the development of vertebral body malformations. © 2010 Blackwell Publishing Ltd.

Digestive enzyme activity in the intestine of Nile tilapia (Oreochromis niloticus L.) under pond and cage farming systems.

PubMed

Santos, Juliana Ferreira; Soares, Karollina Lopes Siqueira; Assis, Caio Rodrigo Dias; Guerra, Carlos Augusto Martins; Lemos, Daniel; Carvalho, Luiz Bezerra; Bezerra, Ranilson Souza

2016-10-01

The effect of different farming systems (cage, pond) upon digestive enzyme activities of Nile tilapia was evaluated. Juvenile Nile tilapia (87.61 ± 1.52 g) were simultaneously cultured in pond and cage systems during 90 days. Cages used nutritional biphasic plan (35 and 32 % crude protein-CP feeds) and ponds used nutritional triphasic plan (35, 32 and 28 % CP feeds). Biometric measurements were monthly performed for adjustments in feeding regimes and removal of intestine tissues to evaluate the performance of enzyme activities. Total proteolytic, amylase and lipase activities were not statistically different between the treatments throughout the periods analyzed (31, 63 and 94 days of culture). However, trypsin and chymotrypsin activities were higher with 31 and 63 days of culture in fish from pond system, suggesting that natural food may have influenced these activities. A positive correlation was observed between the recommended concentration of essential amino acids for Nile tilapia and specific aminopeptidases activity in fish cage system. Substrate-SDS-PAGE revealed 12 active proteolytic bands in both systems. However, integrated density (ID) values were higher in the bands of ponds. Specimens of either cage or pond exhibited five bands of amylolytic activity. Fish from cage and pond systems showed the highest values of ID within 31 days of cultivation. In this study, the complexity of digestive functions could be verified for animals maintained under commercial conditions. Some of the assessed enzymes may show adaptations of their activities and/or expression that allow the fish to achieve a more efficient nutrient assimilation.

Early feeding of carnivorous rainbow trout (Oncorhynchus mykiss) with a hyperglucidic diet during a short period: effect on dietary glucose utilization in juveniles.

PubMed

Geurden, I; Aramendi, M; Zambonino-Infante, J; Panserat, S

2007-06-01

Based on the concept of nutritional programming in higher vertebrates, we tested whether an acute hyperglucidic stimulus during early life could induce a long-lasting effect on carbohydrate utilization in carnivorous rainbow trout. The trout were fed a hyperglucidic diet (60% dextrin) at two early stages of development: either at first feeding (3 days, stimulus 1) or after yolk absorption (5 days, stimulus 2). Before and after the hyperglucidic stimulus, they received a commercial diet until juvenile stage (>10 g). Fish that did not experience the hyperglucidic stimuli served as controls. The short- and long-term effects of the stimuli were evaluated by measuring the expression of five key genes involved in carbohydrate utilization: alpha-amylase, maltase (digestion), sodium-dependent glucose cotransporter (SGLT1; intestinal glucose transport), and glucokinase and glucose-6-phosphatase, involved in the utilization and production of glucose, respectively. The hyperglucidic diet rapidly increased expressions of maltase, alpha-amylase, and glucokinase in stimulus 1 fish and only of maltase in stimulus 2 fish, probably because of a lower plasticity at this later stage of development. In the final challenge test with juveniles fed a 25% dextrin diet, both digestive enzymes were upregulated in fish that had experienced the hyperglucidic stimulus at first feeding, confirming the possibility of modification of some long-term physiological functions in rainbow trout. In contrast, no persistent molecular adaptations were found for the genes involved in glucose transport or metabolism. In addition, growth and postprandial glycemia were unaffected by the stimuli. In summary, our data show that a short hyperglucidic stimulus during early trout life may permanently influence carbohydrate digestion.

Effects of feed restriction to enhance the profitable farming of blackhead seabream Acanthopagrus schlegelii schlegelii in sea cages

NASA Astrophysics Data System (ADS)

Oh, Sung-Yong; Kim, Min-Suk; Kwon, Joon Yeong; Maran, B. A. Venmathi

2013-09-01

The feed intake, growth and body composition of juvenile blackhead seabream Acanthopagrus schlegelii schlegelii (Sparidae) (5.6 g fish-1) were investigated for 16 weeks in sea cages under seven repetitive feeding cycles: every day feeding (control), 6-day feeding and 1-day fasting (F6.1), 5-day feeding and 1-day fasting (F5.1), 4-day feeding and 1-day fasting (F4.1), 3-day feeding and 1-day fasting (F3.1), 2-day feeding and 1-day fasting (F2.1), and 1-day feeding and 1-day fasting (F1.1). The survival of the fish during the experimental period was not different among the feeding cycles. The greatest weight gain of fish was observed in the control, but not significantly different from that of the F6.1 and F5.1 groups (p > 0.05). Total feed intake and daily feed intake decreased with the increase of fasting frequency, however, actual feed intake, feed efficiency and protein efficiency ratio increased with the increase of the fasting frequency. Proximate composition of the whole body of fish was not affected by different feeding cycles. These results suggest that juvenile blackhead seabreams subjected to repetitive feeding cycles of 6- or 5-days feeding and 1 day fasting for 16 weeks could achieve compensatory growth, and that such mild feeding deprivation could save significant amounts of feed without causing any profit reduction that might result from a decrease in fish size or quality.

Species and tissues specific differentiation of processed animal proteins in aquafeeds using proteomics tools.

PubMed

Rasinger, J D; Marbaix, H; Dieu, M; Fumière, O; Mauro, S; Palmblad, M; Raes, M; Berntssen, M H G

2016-09-16

The rapidly growing aquaculture industry drives the search for sustainable protein sources in fish feed. In the European Union (EU) since 2013 non-ruminant processed animal proteins (PAP) are again permitted to be used in aquafeeds. To ensure that commercial fish feeds do not contain PAP from prohibited species, EU reference methods were established. However, due to the heterogeneous and complex nature of PAP complementary methods are required to guarantee the safe use of this fish feed ingredient. In addition, there is a need for tissue specific PAP detection to identify the sources (i.e. bovine carcass, blood, or meat) of illegal PAP use. In the present study, we investigated and compared different protein extraction, solubilisation and digestion protocols on different proteomics platforms for the detection and differentiation of prohibited PAP. In addition, we assessed if tissue specific PAP detection was feasible using proteomics tools. All work was performed independently in two different laboratories. We found that irrespective of sample preparation gel-based proteomics tools were inappropriate when working with PAP. Gel-free shotgun proteomics approaches in combination with direct spectral comparison were able to provide quality species and tissue specific data to complement and refine current methods of PAP detection and identification. To guarantee the safe use of processed animal protein (PAP) in aquafeeds efficient PAP detection and monitoring tools are required. The present study investigated and compared various proteomics workflows and shows that the application of shotgun proteomics in combination with direct comparison of spectral libraries provides for the desired species and tissue specific classification of this heat sterilized and pressure treated (≥133°C, at 3bar for 20min) protein feed ingredient. Copyright © 2016 Elsevier B.V. All rights reserved.

Feeding Ecology of Northeast Atlantic Mackerel, Norwegian Spring-Spawning Herring and Blue Whiting in the Norwegian Sea.

PubMed

Bachiller, Eneko; Skaret, Georg; Nøttestad, Leif; Slotte, Aril

2016-01-01

The Norwegian spring-spawning (NSS) herring (Clupea harengus), blue whiting (Micromesistius poutassou) and Northeast Atlantic (NEA) mackerel (Scomber scombrus) are extremely abundant pelagic planktivores that feed in the Norwegian Sea (NS) during spring and summer. This study investigated the feeding ecology and diet composition of these commercially important fish stocks on the basis of biological data, including an extensive set of stomach samples in combination with hydrographical data, zooplankton samples and acoustic abundance data from 12 stock monitoring surveys carried out in 2005-2010. Mackerel were absent during the spring, but had generally high feeding overlap with herring in the summer, with a diet mainly based on calanoid copepods, especially Calanus finmarchicus, as well as a similar diet width. Stomach fullness in herring diminished from spring to summer and feeding incidence was lower than that of mackerel in summer. However, stomach fullness did not differ between the two species, indicating that herring maintain an equally efficient pattern of feeding as mackerel in summer, but on a diet that is less dominated by copepods and is more reliant on larger prey. Blue whiting tended to have a low dietary overlap with mackerel and herring, with larger prey such as euphausiids and amphipods dominating, and stomach fullness and feeding incidence increasing with length. For all the species, feeding incidence increased with decreasing temperature, and for mackerel so did stomach fullness, indicating that feeding activity is highest in areas associated with colder water masses. Significant annual effects on diet composition and feeding-related variables suggested that the three species are able to adapt to different food and environmental conditions. These annual effects are likely to have an important impact on the predation pressure on different plankton groups and the carrying capacity of individual systems, and emphasise the importance of regular monitoring of pelagic fish diets.

25 CFR 241.3 - Commercial fishing, Annette Islands Reserve.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 25 Indians 1 2013-04-01 2013-04-01 false Commercial fishing, Annette Islands Reserve. 241.3... FISHING IN ALASKA § 241.3 Commercial fishing, Annette Islands Reserve. (a) Definition. Commercial fishing is the taking, fishing for, or possession of fish, shellfish, or other fishery resources with the...

25 CFR 241.3 - Commercial fishing, Annette Islands Reserve.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 25 Indians 1 2014-04-01 2014-04-01 false Commercial fishing, Annette Islands Reserve. 241.3... FISHING IN ALASKA § 241.3 Commercial fishing, Annette Islands Reserve. (a) Definition. Commercial fishing is the taking, fishing for, or possession of fish, shellfish, or other fishery resources with the...

Feeding Behaviour, Swimming Activity and Boldness Explain Variation in Feed Intake and Growth of Sole (Solea solea) Reared in Captivity

PubMed Central

Mas-Muñoz, Julia; Komen, Hans; Schneider, Oliver; Visch, Sander W.; Schrama, Johan W.

2011-01-01

The major economic constraint for culturing sole (Solea solea) is its slow and variable growth. The objective was to study the relationship between feed intake/efficiency, growth, and (non-) feeding behaviour of sole. Sixteen juveniles with an average (SD) growth of 2.7 (1.9) g/kg0.8/d were selected on their growth during a 4-week period in which they were housed communally with 84 other fish. Selected fish were housed individually during a second 4-week period to measure individual feed intake, growth, and behaviour. Fish were hand-fed three times a day during the dark phase of the day until apparent satiation. During six different days, behaviour was recorded twice daily during 3 minutes by direct observations. Total swimming activity, frequency of burying and of escapes were recorded. At the beginning and end of the growth period, two sequential behavioural tests were performed: “Novel Environment” and “Light Avoidance”. Fish housed individually still exhibited pronounced variation in feed intake (CV = 23%), growth (CV = 25%) and behavior (CV = 100%). Differences in feed intake account for 79% of the observed individual differences in growth of sole. Fish with higher variation in feed intake between days and between meals within days had significantly a lower total feed intake (r = −0.65 and r = −0.77) and growth. Active fish showed significantly higher feed intake (r = 0.66) and growth (r = 0.58). Boldness during both challenge tests was related to fast growth: (1) fish which reacted with a lower latency time to swim in a novel environment had significantly higher feed intake (r = −0.55) and growth (r = −0.66); (2) fish escaping during the light avoidance test tended to show higher feed intake (P<0.1) and had higher growth (P<0.05). In conclusion, feeding consistency, swimming activity in the tank, and boldness during behavioral tests are related to feed intake and growth of sole in captivity. PMID:21738651

Feeding behaviour, swimming activity and boldness explain variation in feed intake and growth of sole (Solea solea) reared in captivity.

PubMed

Mas-Muñoz, Julia; Komen, Hans; Schneider, Oliver; Visch, Sander W; Schrama, Johan W

2011-01-01

The major economic constraint for culturing sole (Solea solea) is its slow and variable growth. The objective was to study the relationship between feed intake/efficiency, growth, and (non-) feeding behaviour of sole. Sixteen juveniles with an average (SD) growth of 2.7 (1.9) g/kg(0.8)/d were selected on their growth during a 4-week period in which they were housed communally with 84 other fish. Selected fish were housed individually during a second 4-week period to measure individual feed intake, growth, and behaviour. Fish were hand-fed three times a day during the dark phase of the day until apparent satiation. During six different days, behaviour was recorded twice daily during 3 minutes by direct observations. Total swimming activity, frequency of burying and of escapes were recorded. At the beginning and end of the growth period, two sequential behavioural tests were performed: "Novel Environment" and "Light Avoidance". Fish housed individually still exhibited pronounced variation in feed intake (CV = 23%), growth (CV = 25%) and behavior (CV = 100%). Differences in feed intake account for 79% of the observed individual differences in growth of sole. Fish with higher variation in feed intake between days and between meals within days had significantly a lower total feed intake (r = -0.65 and r = -0.77) and growth. Active fish showed significantly higher feed intake (r = 0.66) and growth (r = 0.58). Boldness during both challenge tests was related to fast growth: (1) fish which reacted with a lower latency time to swim in a novel environment had significantly higher feed intake (r = -0.55) and growth (r = -0.66); (2) fish escaping during the light avoidance test tended to show higher feed intake (P<0.1) and had higher growth (P<0.05). In conclusion, feeding consistency, swimming activity in the tank, and boldness during behavioral tests are related to feed intake and growth of sole in captivity.

The effects of temperature on gastric emptying time of malabar blood snapper (Lutjanus malabaricus, Bloch & Schneider 1801) using X-radiography technique

NASA Astrophysics Data System (ADS)

Mazumder, Sabuj Kanti; Ghaffar, Mazlan Abd.; Das, Simon Kumar

2015-09-01

Water temperature can influence the metabolic rate of ectothermal animal such as, fish. This study aims to investigate the gastric emptying time (GET) of malabar blood snapper (L. malabaricus) at different temperature (22, 26, 30, 34°C) fed with commercial diet pellet. The gastric emptying times at different temperatures were determined X-radiographically, using barium sulfate (BaSO4) as a contrast medium food marker. The food marker and X-radiography showed that initial voidance of fecal matter began 4-8 h after feeding at all temperature. The fastest GET (18 h) was obsereved at 30°C, whereas the longest (28 h) GET was seen at 22°C. GET was increased with increasing temperature up to 30°C whereas decreased at extreme (34°C) and stress temperature (22°C). The findings of this study suggest to culture L. malabaricus at 26-30°C with commercial diet pellet as this temperature ranges escalate the faster digestion process which may contribute faster growth rate of this commercially important fish species. Overall, the data obtained from this study may have important consequences for optimization of commercial production of malabar blood snapper.

The effects of temperature on gastric emptying time of malabar blood snapper (Lutjanus malabaricus, Bloch & Schneider 1801) using X-radiography technique

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mazumder, Sabuj Kanti, E-mail: sabujsau@gmail.com; Ghaffar, Mazlan Abd., E-mail: magfish05@yahoo.com; Institute of Tropical Aquaculture, University of Malaysia Terengganu, 21030 Kuala Terengganu

Water temperature can influence the metabolic rate of ectothermal animal such as, fish. This study aims to investigate the gastric emptying time (GET) of malabar blood snapper (L. malabaricus) at different temperature (22, 26, 30, 34°C) fed with commercial diet pellet. The gastric emptying times at different temperatures were determined X-radiographically, using barium sulfate (BaSO{sub 4}) as a contrast medium food marker. The food marker and X-radiography showed that initial voidance of fecal matter began 4-8 h after feeding at all temperature. The fastest GET (18 h) was obsereved at 30°C, whereas the longest (28 h) GET was seen at 22°C. GET wasmore » increased with increasing temperature up to 30°C whereas decreased at extreme (34°C) and stress temperature (22°C). The findings of this study suggest to culture L. malabaricus at 26-30°C with commercial diet pellet as this temperature ranges escalate the faster digestion process which may contribute faster growth rate of this commercially important fish species. Overall, the data obtained from this study may have important consequences for optimization of commercial production of malabar blood snapper.« less

Fisheries, low oxygen and climate change: how much do we really know?

PubMed

Townhill, B L; Pinnegar, J K; Righton, D A; Metcalfe, J D

2017-03-01

As a result of long-term climate change, regions of the ocean with low oxygen concentrations are predicted to occur more frequently and persist for longer periods of time in the future. When low levels of oxygen are present, this places additional pressure on marine organisms to meet their metabolic requirements, with implications for growth, feeding and reproduction. Extensive research has been carried out on the effects of acute hypoxia, but far less on long-term chronic effects of low oxygen zones, especially with regard to commercially important fishes and shellfishes. To provide further understanding on how commercial species could be affected, the results of relevant experiments must support population and ecosystem models. This is not easy because individual effects are wide-ranging; for example, studies to date have shown that low oxygen zones can affect predator-prey relationships as some species are able to tolerate low oxygen more than others. Some fishes may move away from areas until oxygen levels return to acceptable levels, while others take advantage of a reduced start response in prey fishes and remain in the area to feed. Sessile or less mobile species such as shellfishes are unable to move out of depleted oxygen zones. Some species can tolerate low oxygen levels for only short periods of time, while others are able to acclimatize. To advance the knowledge-base further, a number of promising technological and modelling-based developments and the role of physiological data within these, are proposed. These include advances in remote telemetry (tagging) and sensor technologies, trait-based analyses to provide insight into how whole assemblages might respond in the future, research into long-term adaptability of species, population and ecosystem modelling techniques and quantification of economic effects. In addition, more detailed oxygen monitoring and projections are required to better understand the likely temporal and local-scale changes in oxygen. © 2016 Crown Copyright. Journal of Fish Biology © 2016 The Fisheries Society of the British Isles.

The use of food wastes as feed ingredients for culturing grass carp (Ctenopharyngodon idellus) in Hong Kong.

PubMed

Choi, W M; Lam, C L; Mo, W Y; Wong, M H

2016-04-01

Different types of food wastes, e.g., meats, bones, cereals, fruits, and vegetables, were collected from hotels in Hong Kong, mixed in different ratio, and processed into feed pellets (food wastes (FWs) A, B, and C) for feeding trials in aquaculture species. Grass carp fed with cereal-dominant feed (FW A) showed the best growth (in terms of specific growth rate, relative weight gain, and protein efficiency ratio), among all food waste feeds. However, the growth rates of food waste groups especially the meat product-contained feeds (FW B and FW C) were lower than the commercial feed, Jinfeng(®) 613 formulation (control). The results indicated that grass carp utilized plant proteins better than animal proteins and preferred carbohydrate as a major energy source than lipid. The high-lipid content in feed containing meat products was also a possible reason for hindering growth and resulted high body lipid. It is suggested that lipid should be removed in the preparation of food waste feed or further investigations by implementing supplements, e.g., enzymes in feed to enhance lipid or protein utilization by fish. This utilization of food waste could be an effective and practical way to deal with these wastes in this densely populated city.

50 CFR 18.24 - Taking incidental to commercial fishing operations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false Taking incidental to commercial fishing... commercial fishing operations. Persons may take marine mammals incidental to commercial fishing operations... of marine mammals permitted in the course of commercial fishing operations be reduced to...

50 CFR 18.24 - Taking incidental to commercial fishing operations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Taking incidental to commercial fishing... commercial fishing operations. Persons may take marine mammals incidental to commercial fishing operations... of marine mammals permitted in the course of commercial fishing operations be reduced to...

50 CFR 18.24 - Taking incidental to commercial fishing operations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Taking incidental to commercial fishing... commercial fishing operations. Persons may take marine mammals incidental to commercial fishing operations... of marine mammals permitted in the course of commercial fishing operations be reduced to...

50 CFR 18.24 - Taking incidental to commercial fishing operations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Taking incidental to commercial fishing... commercial fishing operations. Persons may take marine mammals incidental to commercial fishing operations... of marine mammals permitted in the course of commercial fishing operations be reduced to...

Coconut oil and beef tallow, but not tricaprylin, can replace menhaden oil in the diet of red drum (Sciaenops ocellatus) without adversely affecting growth or fatty acid composition.

PubMed

Craig, S R; Gatlin, D M

1995-12-01

The ability of juvenile red drum (Sciaenops ocellatus) to utilize medium-chain triglycerides (MCT) and other saturated dietary lipids was investigated in two 6-wk feeding experiments. Diets contained solvent-extracted menhaden fish meal to which menhaden fish oil (control), coconut oil, corn oil, beef tallow or various levels of MCT as tricaprylin (30, 46, 65 and 80% of total lipid) were added. Diets were fed to triplicate groups of juvenile red drum in aquaria containing brackish (6%) water. In the first feeding experiment, red drum fed the control diet had the greatest weight gains and feed efficiencies. Weight gain, but not feed was slightly, of fish fed corn oil and fish fed coconut oil was slightly (P < 0.05) lower. In the second feeding experiment, fish fed coconut oil and those fed beef tallow had significantly higher weight gains and feed efficiencies than did fish fed the control diet. Fish fed the diets containing tricaprylin at all inclusion levels in both feeding experiments had significantly lower weight gains and feed efficiencies and higher levels of beta-hydroxybutyric acid in plasma. Fish fed diets with high levels of MCT also had lower (n-3) and greater (n-6) fatty acid levels in the neutral lipid fraction of muscle tissue compared with fish fed the control diet. Coconut oil and beef tallow consistently resulted in greater liver lipid deposition but had variable effects on other tissue indices. Saturated dietary lipids had variable effects on fatty acid composition of muscle polar and neutral lipid fractions.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of nutritional status on metabolic rate, exercise and recovery in a freshwater fish.

PubMed

Gingerich, Andrew James; Philipp, David P; Suski, Cory D

2010-03-01

The influence of feeding on swimming performance and exercise recovery in fish is poorly understood. Examining swimming behavior and physiological status following periods of feeding and fasting is important because wild fish often face periods of starvation. In the current study, researchers force fed and fasted groups of largemouth bass (Micropterus salmoides) of similar sizes for a period of 16 days. Following this feeding and fasting period, fish were exercised for 60 s and monitored for swimming performance and physiological recovery. Resting metabolic rates were also determined. Fasted fish lost an average of 16 g (nearly 12%) of body mass, while force fed fish maintained body mass. Force fed fish swam 28% further and required nearly 14 s longer to tire during exercise. However, only some physiological conditions differed between feeding groups. Resting muscle glycogen concentrations was twofold greater in force fed fish, at rest and throughout recovery, although it decreased in both feeding treatments following exercise. Liver mass was nearly three times greater in force fed fish, and fasted fish had an average of 65% more cortisol throughout recovery. Similar recovery rates of most physiological responses were observed despite force fed fish having a metabolic rate 75% greater than fasted fish. Results are discussed as they relate to largemouth bass starvation in wild systems and how these physiological differences might be important in an evolutionary context.

Long-term functional changes in an estuarine fish assemblage.

PubMed

Baptista, J; Martinho, F; Nyitrai, D; Pardal, M A; Dolbeth, M

2015-08-15

The functional diversity of the fish assemblages of the Mondego estuary was studied for a discontinuous 30-year period (1988-2012). During this time, hydrological changes occurred due to man-induced alterations and weather extremes. These changes led to alterations in the structure and function of the fish community. Species richness and functional richness decreased over time and the fish community started to explore new micro-habitats and food resources. Before severe hydrological changes, the community was dominated by pelagic, detritivorous and species with wider salinity ranges. After, the community became dominated by demersal, benthic, piscivorous and marine species. During a drought, omnivorous became increasingly important, reflecting greater possibilities of using available feeding resources. We have also found an increase in sub-tropical species throughout the years, which might be related to gradual temperature increases at a global scale. This study also confirmed estuaries as extremely important for restocking several commercial species. Copyright © 2015 Elsevier Ltd. All rights reserved.

Diets labelled with (13)C-starch and (15)N-protein reveal daily rhythms of nutrient use in gilthead sea bream (Sparus aurata).

PubMed

Felip, Olga; Blasco, Josefina; Ibarz, Antoni; Martín-Pérez, Miguel; Fernández-Borràs, Jaume

2015-01-01

All functions in animals rely on daily rhythms, and mealtime can act as a rhythm-marker of nutrients assimilation and use. The effects of meal timing and food composition on carbohydrate use and protein retention of gilthead sea bream were studied. Three groups were fed twice a day (10am and at 5pm) for two months with two alternating diets: a commercial diet (Cd) and a high-carbohydrate, low-protein diet (Ed). The Ed/Cd group received the Ed diet in the morning and the Cd diet in the afternoon, and the Cd/Ed group received these diets in the reverse order. The Cd/Cd group only received the commercial diet (control group). After 56days, two force-feeding experiments (PF1 and PF2) measured for all three groups the fate of a single meal labelled with (15)N-protein and (13)C-starch through the retention of both isotopes in the main organs and tissue reserves. In PF1 fish were fed at 10am (morning mealtime), and in PF2 at 5pm (afternoon mealtime). Fish were sampled at the next two mealtimes (PF1: 7 and 24h post-feeding, PF2: 17 and 24h post-feeding). Nutrients recovery differed according to, first, the dietary regime, and second, the last meal received (Cd or Ed). Daily lower protein intake was compensated with higher protein retention combined with more use of carbohydrates for energy. Nevertheless, carbohydrates from the morning meal were used more efficiently. So, the use of carbohydrate for energy production and protein for growth can be improved by adjusting diet composition and mealtime. Copyright © 2014 Elsevier Inc. All rights reserved.

50 CFR 404.10 - Commercial fishing.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Commercial fishing. 404.10 Section 404.10... MARINE NATIONAL MONUMENT § 404.10 Commercial fishing. (a) Lobster fishing. Any commercial lobster fishing permit is subject to a zero annual harvest limit condition. (b) Fishing and bottomfish and pelagic...

50 CFR 404.10 - Commercial fishing.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Commercial fishing. 404.10 Section 404.10... MARINE NATIONAL MONUMENT § 404.10 Commercial fishing. (a) Lobster fishing. Any commercial lobster fishing permit is subject to a zero annual harvest limit condition. (b) Fishing and bottomfish and pelagic...

50 CFR 404.10 - Commercial fishing.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 11 2014-10-01 2014-10-01 false Commercial fishing. 404.10 Section 404.10... MONUMENT § 404.10 Commercial fishing. (a) Lobster fishing. Any commercial lobster fishing permit is subject to a zero annual harvest limit condition. (b) Fishing and bottomfish and pelagic species. (1...

25 CFR 241.3 - Commercial fishing, Annette Islands Reserve.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 25 Indians 1 2012-04-01 2011-04-01 true Commercial fishing, Annette Islands Reserve. 241.3 Section 241.3 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE INDIAN FISHING IN ALASKA § 241.3 Commercial fishing, Annette Islands Reserve. (a) Definition. Commercial fishing is the...

50 CFR 404.10 - Commercial fishing.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 11 2013-10-01 2013-10-01 false Commercial fishing. 404.10 Section 404.10... MARINE NATIONAL MONUMENT § 404.10 Commercial fishing. (a) Lobster fishing. Any commercial lobster fishing permit is subject to a zero annual harvest limit condition. (b) Fishing and bottomfish and pelagic...

50 CFR 404.10 - Commercial fishing.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 11 2012-10-01 2012-10-01 false Commercial fishing. 404.10 Section 404.10... MARINE NATIONAL MONUMENT § 404.10 Commercial fishing. (a) Lobster fishing. Any commercial lobster fishing permit is subject to a zero annual harvest limit condition. (b) Fishing and bottomfish and pelagic...

Sodium salt medium-chain fatty acids and Bacillus-based probiotic strategies to improve growth and intestinal health of gilthead sea bream (Sparus aurata)

PubMed Central

Simó-Mirabet, Paula; Piazzon, M. Carla; Calduch-Giner, Josep Alvar; Ortiz, Álvaro; Puyalto, Mónica; Sitjà-Bobadilla, Ariadna

2017-01-01

Background The increased demand for fish protein has led to the intensification of aquaculture practices which are hampered by nutritional and health factors affecting growth performance. To solve these problems, antibiotics have been used for many years in the prevention, control and treatment against disease as well as growth promoters to improve animal performance. Nowadays, the use of antibiotics in the European Union and other countries has been completely or partially banned as a result of the existence of antibiotic cross-resistance. Therefore, a number of alternatives, including enzymes, prebiotics, probiotics, phytonutrients and organic acids used alone or in combination have been proposed for the improvement of immunological state, growth performance and production in livestock animals. The aim of the present study was to evaluate two commercially available feed additives, one based on medium-chain fatty acids (MCFAs) from coconut oil and another with a Bacillus-based probiotic, in gilthead sea bream (GSB, Sparus aurata), a marine farmed fish of high value in the Mediterranean aquaculture. Methods The potential benefits of adding two commercial feed additives on fish growth performance and intestinal health were assessed in a 100-days feeding trial. The experimental diets (D2 and D3) were prepared by supplementing a basal diet (D1) with MCFAs in the form of a sodium salt of coconut fatty acid distillate (DICOSAN®; Norel, Madrid, Spain), rich on C-12, added at 0.3% (D2) or with the probiotic Bacillus amyloliquefaciens CECT 5940, added at 0.1% (D3). The study integrated data on growth performance, blood biochemistry, histology and intestinal gene expression patterns of selected markers of intestinal function and architecture. Results MCFAs in the form of a coconut oil increased feed intake, growth rates and the surface of nutrient absorption, promoting the anabolic action of the somatotropic axis. The probiotic (D3) induced anti-inflammatory and anti-oxidant effects with changes in circulating cortisol, immunoglobulin M, leukocyte respiratory burst, and mucosal expression levels of cytokines, lymphocyte markers and immunoglobulin T. Discussion MCFA supplementation showed positive effects on GSB growth and intestinal architecture acting mainly in the anterior intestine, where absorption takes place. The probiotic B. amyloliquefaciens CECT 5940 exhibited key effects in the regulation of the immune status inducing anti-inflammatory and anti-oxidant effects which can be potentially advantageous upon infection or exposure to other stressors. The potential effects of these feed additives in GSB are very promising to improve health and disease resistance in aquaculture. PMID:29226031

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gingerich, Andrew J.; Philipp, D. P.; Suski, C. D.

The influence of feeding on swimming performance and exercise recovery in fish is poorly understood. Examining swimming behavior and physiological status following periods of feeding and fasting is important because wild fish often face periods of starvation. In the current study, researchers force fed and fasted groups of largemouth bass (Micropterus salmoides) of similar sizes for a period of 16 days. Following this feeding and fasting period, fish were exercised for 60 s and monitored for swimming performance and physiological recovery. Resting metabolic rates were also determined. Fasted fish lost an average of 16 g (nearly 12%) of body mass,more » while force fed fish maintained body mass. Force fed fish swam 28% further and required nearly 14 s longer to tire during exercise. However, only some physiological conditions differed between feeding groups. Resting muscle glycogen concentrations was twofold greater in force fed fish, at rest and throughout recovery, although it decreased in both feeding treatments following exercise. Liver mass was nearly three times greater in force fed fish, and fasted fish had an average of 65% more cortisol throughout recovery. Similar recovery rates of most physiological responses were observed despite force fed fish having a metabolic rate 75% greater than fasted fish. Results are discussed as they relate to largemouth bass starvation in wild systems and how these physiological differences might be important in an evolutionary context.« less

Occurrence of PCDD/F, PCB, PBDE, PFAS, and organotin compounds in fish meal, fish oil and fish feed.

PubMed

Suominen, K; Hallikainen, A; Ruokojärvi, P; Airaksinen, R; Koponen, J; Rannikko, R; Kiviranta, H

2011-10-01

We analysed polychlorinated dibenzo-p-dioxins and furans (PCDD/F, dioxins), and polychlorinated biphenyls (PCB) in 13 fish meal, five fish oil, and seven fish feed samples. Polybrominated diphenyl ethers (PBDE), organotin compounds (OTC), and perfluoroalkylated substances (PFAS) were analysed in ten fish meal, two fish oil, and two fish feed samples. All measured TEQ concentrations of PCDD/F and PCB were below the maximum levels set by Directive 2002/32/EC. There was no correlation between concentrations of WHOPCDD/F-TEQ and indicator PCB in our samples. The most common congeners among PBDEs were BDE-47 and BDE-100. BDE-209 was present in five fish meals of the ten analysed. Tributyltin (TBT) was the predominant congener in all samples except in three fish meals, where monobutyltin (MBT) was the major congener. Perfluorooctane sulphonate (PFOS) was the predominant congener in six fish meals of the ten analysed. There was large variation in concentrations and congener distributions of the studied compounds between our samples. Our results underline a need to pay special attention to the origin and purity of feed raw material of marine origin. Copyright © 2011 Elsevier Ltd. All rights reserved.

A survey of chemical constituents in National Fish Hatchery fish feed

USGS Publications Warehouse

Maule, Alec G.; Gannam, Ann; Davis, Jay

2006-01-01

Recent studies have demonstrated that various fish feeds contain significant concentrations of contaminants, many of which can bioaccumulate and bioconcentrate in fish. It appears that numerous organochlorine (OC) contaminants are present in the fish oils and fish meals used in feed manufacture, and some researchers speculate that all fish feeds contain measurable levels of some contaminants. To determine the presence and concentration of contaminants in feeds used in National Fish Hatcheries managed by the U.S. Fish & Wildlife Service, we systematically collected samples of feed from 11 hatcheries that raise cold-water species, and analyzed them for a suite of chemical contaminants. All of the samples (collected from October 2001 to October 2003) contained measurable concentrations of at least one dioxin, furan, polychlorinated biphenyl (PCB) congener, or dichlorodiphenyltrichloroethane (DDT) metabolite. All samples which were assayed for all contaminants contained one or more of those classes of compounds and most contained more than one; dioxin was detected in 39 of the 55 samples for which it was assayed, 24 of 55 contained furans and 24 of 55 samples contained DDT or its metabolites. There with 10- to 150-fold differences in the range in concentrations of the additive totals for PCBs, dioxins, furans and DDT. Although PCBs were the most commonly detected contaminant in our study (all samples in which it was assayed), the concentrations (range: 0.07 to 10.46 ng g·1 wet weight) were low compared to those reported previously. In general, we also found lower levels of organochlorine contaminants than have been reported previously in fish feed. Perhaps most notable is the near absence of OC pesticides~xcept for DDT (and its metabolites) and just two samples containing benzene hexachloride (Lindane). While contaminant concentrations were generally low, the ecological impacts can not be determined without a measure of the bioaccumulation of these compounds in the fish and the fate of these compounds after the fish are released from the hatcheries.

Histopathology and culturable bacteria associated with "big belly" and "skin nodule" syndromes in ornamental Siamese fighting fish, Betta splendens.

PubMed

Dong, H T; Senapin, S; Phiwsaiya, K; Techatanakitarnan, C; Dokladda, K; Ruenwongsa, P; Panijpan, B

2018-06-02

The Siamese fighting fish (Betta splendens) is one of the popular aquarium ornamental fish in the global trade. Large numbers of ornamental fish farmed in central Thailand suffered from two common syndromes; preliminarily named skin nodule syndrome (SNS) and big belly syndrome (BBS): they showed noticeable clinical signs of abnormal appearances resulting in depressed saleability. Since very few specifics are known about causative agents of these syndromes, this study aimed at investigating histopathological features and culturable bacteria associated with these fish infected in the process of farming. Histopathologically, SNS fish consistently exhibited necrosis and severe melanization in the muscles and multiple internal organs. Whereas BBS fish exhibited either typical granulomas or tissue damage associated with acid-fast stained bacteria and Gram negative bacteria, respectively. Six different Gram negative bacterial species were recovered from BBS fish while 23 bacterial species belonging to 14 genera were recovered from fish suffering from SNS. Most of the culturable bacteria are new to betta fish and some of them are known to be marine bacteria, suggesting possible entry route via a contaminated live feed, commercial Artemia shrimp. The true causative agents of these syndromes remain unclear. However, histopathological changes and existence of a wide range of bacteria associated with the naturally diseased fish suggest involvement of multiple bacterial infections. Copyright © 2018 Elsevier Ltd. All rights reserved.

Immediate systemic allergic reaction in an infant to fish allergen ingested through breast milk

PubMed Central

Arima, Takayasu; Campos-Alberto, Eduardo; Funakoshi, Hiraku; Inoue, Yuzaburo; Tomiita, Minako; Kohno, Yoichi

2016-01-01

This is a rare case report of systemic allergic reaction to fish allergen ingested through breast milk. Mother ate raw fish more than 3 times a week. Her consumption of fish was associated with urticaria and wheeze in an infant via breast-feeding. Fish-specific IgE antibodies were detected by skin prick test but not by in vitro IgE test. This case demonstrates that fish protein ingested by mother can cause an immediate systemic allergic reaction in offspring through breast-feeding. Although fish intake is generally recommended for prevention of allergy, one should be aware that frequent intake of fish by a lactating mother may sensitize the baby and induce an allergic reaction through breast-feeding. PMID:27803887

Development of a foraging model framework to reliably estimate daily food consumption by young fishes

USGS Publications Warehouse

Deslauriers, David; Rosburg, Alex J.; Chipps, Steven R.

2017-01-01

We developed a foraging model for young fishes that incorporates handling and digestion rate to estimate daily food consumption. Feeding trials were used to quantify functional feeding response, satiation, and gut evacuation rate. Once parameterized, the foraging model was then applied to evaluate effects of prey type, prey density, water temperature, and fish size on daily feeding rate by age-0 (19–70 mm) pallid sturgeon (Scaphirhynchus albus). Prey consumption was positively related to prey density (for fish >30 mm) and water temperature, but negatively related to prey size and the presence of sand substrate. Model evaluation results revealed good agreement between observed estimates of daily consumption and those predicted by the model (r2 = 0.95). Model simulations showed that fish feeding on Chironomidae or Ephemeroptera larvae were able to gain mass, whereas fish feeding solely on zooplankton lost mass under most conditions. By accounting for satiation and digestive processes in addition to handling time and prey density, the model provides realistic estimates of daily food consumption that can prove useful for evaluating rearing conditions for age-0 fishes.

Effects of surgically and gastrically implanted radio transmitters on growth and feeding behavior of juvenile chinook salmon

USGS Publications Warehouse

Adams, N.S.; Rondorf, D.W.; Evans, S.D.; Kelly, J.E.

1997-01-01

We examined the effects of surgically and gastrically implanted radio transmitters (representing 2.3-5.5% of body weight) on the growth and feeding behavior of 192 juvenile chinook salmon Oncorhynchus tshawytscha (114-159 mm in fork length). Throughout the 54-d study, the 48 fish with transmitters in their stomachs (gastric fish) consistently grew more slowly than fish with surgically implanted transmitters (surgery fish), fish with surgery but no implanted transmitter (sham-surgery fish), or fish exposed only to handling (control fish). Growth rates of surgery fish were also slightly impaired at day 21, but by day 54 they were growing at rates comparable with those of control fish. Despite differences in growth, overall health was similar among all test fish. However, movement of the transmitter antenna caused abrasions at the corner of the mouth in all gastric fish, whereas only 22% of the surgery fish had inflammation around the antenna exit wound. Feeding activity was similar among groups, but gastric fish exhibited a coughing behavior and appeared to have difficulty retaining swallowed food. Because growth and feeding behavior were less affected by the presence of surgically implanted transmitters than by gastric implants, we recommend surgically implanting transmitters for biotelemetry studies of juvenile chinook salmon between 114 and 159 mm fork length.

Waste feed from coastal fish farms: A trophic subsidy with compositional side-effects for wild gadoids

NASA Astrophysics Data System (ADS)

Fernandez-Jover, Damian; Martinez-Rubio, Laura; Sanchez-Jerez, Pablo; Bayle-Sempere, Just T.; Lopez Jimenez, Jose Angel; Martínez Lopez, Francisco Javier; Bjørn, Pål-Arne; Uglem, Ingebrigt; Dempster, Tim

2011-03-01

Aquaculture of carnivorous fish species in sea-cages typically uses artificial feeds, with a proportion of these feeds lost to the surrounding environment. This lost resource may provide a trophic subsidy to wild fish in the vicinity of fish farms, yet the physiological consequences of the consumption of waste feed by wild fish remain unclear. In two regions in Norway with intensive aquaculture, we tested whether wild saithe ( Pollachius virens) and Atlantic cod ( Gadus morhua) associated with fish farms (F assoc), where waste feed is readily available, had modified diets, condition and fatty acid (FA) compositions in their muscle and liver tissues compared to fish unassociated (UA) with farms. Stomach content analyses revealed that both cod and saithe consumed waste feed in the vicinity of farms (6-96% of their diet was composed of food pellets). This translated into elevated body and liver condition compared to fish caught distant from farms for cod at both locations and elevated body condition for saithe at one of the locations. As a consequence of a modified diet, we detected significantly increased concentrations of terrestrial-derived fatty acids (FAs) such as linoleic (18:2ω6) and oleic (18:1ω9) acids and decreased concentrations of DHA (22:6ω3) in the muscle and/or liver of F assoc cod and saithe when compared with UA fish. In addition, the ω3:ω6 ratio clearly differed between F assoc and UA fish. Linear discriminant analysis (LDA) correctly classified 97% of fish into F assoc or UA origin for both cod and saithe based on the FA composition of liver tissues, and 89% of cod and 86% of saithe into F assoc or UA origin based on the FA composition of muscle. Thus, LDA appears a useful tool for detecting the influence of fish farms on the FA composition of wild fish. Ready availability of waste feed with high protein and fat content provides a clear trophic subsidy to wild fish in coastal waters, yet whether the accompanying side-effect of altered fatty acid compositions affects physiological performance or reproductive potential requires further research.

Feeding response of sport fish after electrical immobilization, chemical sedation, or both

USGS Publications Warehouse

Meinertz, Jeffery R.; Fredricks, Kim T.; Ambrose, Ryan D.; Jackan, Leanna M.; Wise, Jeremy K.

2012-01-01

Fishery managers frequently capture wild fish for a variety of fishery management activities. Though some activities can be accomplished without immobilizing the fish, others are accomplished more readily, humanely, and safely (for both the handler and the fish) when fish are immobilized by physical (e.g., electrical immobilization) or chemical sedation. A concern regarding the use of chemical sedatives is that chemical residues may remain in the fillet tissue after the fish recovers from sedation. If those residues are harmful to humans, there is some risk that a postsedated fish released to public waters may be caught and consumed by an angler. To characterize this risk, a series of four trials were conducted. Three trials assessed feeding activity after hatchery-reared fish were electrically immobilized, chemically sedated, or both, and one trial assessed the likelihood of an angler catching a wild fish that had been electrically immobilized and chemically sedated. Results from the first trial indicated that the feeding activity of laboratory habituated fish was variable among and within species after electrical immobilization, chemical sedation, or both. Results from the second trial indicated that the resumption of feeding activity was rapid after being mildly sedated for 45 min. Results from the third trial indicated that the feeding activity of outdoor, hatchery-reared fish was relatively aggressive after fish had been chemically sedated. Results from the fourth trial indicated that the probability of capturing wild fish in a more natural environment by angling after fish had been electrically immobilized and chemically sedated is not likely, i.e., in a group of five fish caught, 3 out of 100 times one would be a fish that had been sedated.

LC-MS/MS methods for sulfadimethoxine and ormetoprim analysis in feed and fish fillet and a leaching study for feed after alternative procedures for the incorporation of drugs.

PubMed

Fais, Ana Paula; Franco, Rodolfo Scarpino Barboza; da Silva, Agnaldo Fernando Baldo; de Freitas, Osvaldo; Paschoal, Jonas Augusto Rizzato

2017-04-01

This paper describes the method development for sulfadimethoxine (SDM) and ormetoprim (OMP) quantitation in fish feed and fish fillet employing LC-MS/MS. In order to assess the reliability of the analytical method, valuation was undertaken as recommended by guidelines proposed by the Brazilian Ministry of Agriculture. The calibration curve for the quantification of both drugs in feed showed adequate linearity (r > 0.99), precision (CV < 12%) and trueness ranging from 97% to 100%. The method for the determination of SDM and OMP residues in fish fillet involved a simple sample preparation procedure that had adequate linearity (r > 0.99), precision (CV < 16%) and trueness around 100%, with CCα < 100.2 ng g - 1 and CCβ < 100.4 ng g - 1 . With a goal of avoiding the risk of drug leaching from feed into the aquatic environment during fish medication via the oral route, different procedures for drug incorporation into feed were evaluated. Coating feed pellets with ethyl cellulose polymer containing the drug showed promising results. In this case, medicated feed released drugs to water at a level below 6% when the medicated feed stayed in the water for up to 15 min.

25 CFR 241.5 - Commercial fishing, Karluk Indian Reservation.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 25 Indians 1 2014-04-01 2014-04-01 false Commercial fishing, Karluk Indian Reservation. 241.5... FISHING IN ALASKA § 241.5 Commercial fishing, Karluk Indian Reservation. (a) Definition. The Karluk Indian... Karluk Indian Reservation shall be open to commercial fishing by bona fide native inhabitants of the...

Effect of production quotas on economic and environmental values of growth rate and feed efficiency in sea cage fish farming.

PubMed

Besson, M; de Boer, I J M; Vandeputte, M; van Arendonk, J A M; Quillet, E; Komen, H; Aubin, J

2017-01-01

In sea cage fish farming, production quotas aim to constrain the impact of fish farming on the surrounding ecosystem. It is unknown how these quotas affect economic profitability and environmental impact of genetic improvement. We combined bioeconomic modelling with life cycle assessment (LCA) to calculate the economic (EV) and environmental (ENV) values of thermal growth coefficient (TGC) and feed conversion ratio (FCR) of sea bass reared in sea cages, given four types of quota commonly used in Europe: annual production (Qprod), annual feed distributed (Qannual_feed), standing stock (Qstock), and daily feed distributed (Qdaily_feed). ENV were calculated for LCA impact categories climate change, eutrophication and acidification. ENV were expressed per ton of fish produced per year (ENV(fish)) and per farm per year (ENV(farm)). Results show that irrespective of quota used, EV of FCR as well as ENV(fish) and ENV(farm) were always positive, meaning that improving FCR increased profit and decreased environmental impacts. However, the EV and the ENV(fish) of TGC were positive only when quota was Qstock or Qdaily_feed. Moreover, the ENV(farm) of TGC was negative in Qstock and Qdaily_feed quotas, meaning that improving TGC increased the environmental impact of the farm. We conclude that Qstock quota and Qdaily_feed quota are economically favorable to a genetic improvement of TGC, a major trait for farmers. However, improving TGC increases the environmental impact of the farm. Improving FCR represents a good opportunity to balance out this increase but more information on its genetic background is needed to develop breeding programs improving FCR.

Feeding ecology of Brook Silverside, Golden Shiner, and Subyearling Pumpkinseed in a Lake Ontario embayment

USGS Publications Warehouse

Johnson, James H.; Chalupnicki, Marc; Abbett, Ross; Diaz, Avriel R; Nack, Christopher C

2017-01-01

Fish feeding ecology has been shown to vary over a 24-h period in terms of the prey consumed and feeding intensity. Consequently, in order to best determine the interspecific feeding associations within a fish community, examination of the diet at multiple times over a 24-h period is often necessary. We examined the diel feeding ecology of three fish species that were numerically dominant in a Lake Ontario embayment during summer. The diet of each of the three species, young-of-year Pumpkinseed Lepomis gibbosus, Golden Shiner Notemigonus crysoleucas, and Brook Silverside Labidesthes sicculus, was distinct with no significant overlap in diet composition occurring within any of the 4-h time intervals. The diet composition of each species suggested that Brook Silverside were feeding at the surface (terrestrial invertebrates and aquatic surface dwelling hemipterans), whereas young-of-year Pumpkinseed (amphipods) and Golden Shiner (tipulids) were feeding on different benthic prey. Differences in feeding periodicity were most pronounced for young-of-year Pumpkinseed. Our findings provide valuable insights on interspecific feeding associations among these three fish species during summer in a Lake Ontario embayment.

Comparison of time-restricted and ad libitum self-feeding on the growth, feeding behavior and daily digestive enzyme profiles of Atlantic salmon

NASA Astrophysics Data System (ADS)

Shi, Ce; Liu, Ying; Yi, Mengmeng; Zheng, Jimeng; Tian, Huiqin; Du, Yishuai; Li, Xian; Sun, Guoxiang

2017-07-01

Although it has been hypothesized that a predictable feeding regime in animals allows physiological variables to be adjusted to maximize nutrient utilization and, hence, better growth performance, the assumption has rarely been tested. This study compares the effects of time-restricted versus free access self-feeding on the growth, feeding behavior and daily digestive enzyme rhythms of Atlantic salmon ( Salmo salar). In an experiment that lasted 6 weeks, fish (109.9 g) were divided into two groups: group 1 had free access to a self-feeder (FA); group 2 received three meals per day (2 h per meal) at dawn, midday and dusk via a time-restricted self-feeder (TR). At the end of the experiment, the fish were sampled every 3 h over a 24-h period. The results showed that the TR fish quickly synchronized their feeding behavior to the feeding window and their blood glucose showed a significant postprandial increase, while FA fish displayed no statistically significant rhythms ( P>0.05). Pepsin activity of TR fish also showed a significant daily rhythm ( P<0.05) with the acrophase at the second feed and a decrease over the next 12 h. Average daily trypsin, lipase and amylase levels of FA fish were significantly lower than those of TR fish ( P<0.01); however, the growth performance of both groups was similar ( P>0.05). In conclusion, the study failed to confirm a link between the entrainment of daily digestive enzyme profiles and growth performance, with the TR group showing comparatively poor blood glucose regulation.

36 CFR 13.1146 - What other closures and restrictions apply to commercial fishermen and commercial fishing vessels?

Code of Federal Regulations, 2014 CFR

2014-07-01

... IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Commercial Fishing § 13.1146... Inlets. (b) Commercial fishing in the waters of the west arm of Glacier Bay north of 58° 50.0′ N latitude... fishing regulations. (c) Commercial fishing in the east arm of Glacier Bay, north of an imaginary line...

36 CFR 13.1146 - What other closures and restrictions apply to commercial fishermen and commercial fishing vessels?

Code of Federal Regulations, 2012 CFR

2012-07-01

... IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Commercial Fishing § 13.1146... Inlets. (b) Commercial fishing in the waters of the west arm of Glacier Bay north of 58° 50.0′ N latitude... fishing regulations. (c) Commercial fishing in the east arm of Glacier Bay, north of an imaginary line...

Preliminary Evaluation on the Effects of Feeds on the Growth and Early Reproductive Performance of Zebrafish (Danio rerio)

PubMed Central

2012-01-01

This study evaluated the effects of several commercially available feeds and different feeding regimes on the growth and early reproductive performance of zebrafish (Danio rerio). Juvenile zebrafish (n= 20; 5.06 ± 0.69 mg) were stocked into each of 24 tanks (volume, 2 L); 3 tanks were assigned to each of 8 feeding combinations for a period of 60 d. At the end of 60 d, 2 male and 2 female fish from each tank were pooled by dietary treatment (n = 6) and used to evaluate the effects of feeding combinations on early reproductive performance. Zebrafish fed dietary treatments 3 and 7 had significantly greater weight gain than zebrafish fed diet 5. Mean spawning success was significantly greater in zebrafish fed the control diet (Artemiaonly) than in those fed diet 1. Mean hatch rates were greater in zebrafish fed the control feed and diets 1, 2, 3, 5, and 6 than zebrafish fed diet 4. Additional results suggest that female zebrafish are sexually mature after 90 d post fertilization and that fertilization rates are the limiting factor in early reproduction. PMID:23043806

Growth performance, innate immune responses and disease resistance of fingerling blunt snout bream, Megalobrama amblycephala adapted to different berberine-dietary feeding modes.

PubMed

Xu, Wei-Na; Chen, Dan-Hong; Chen, Qing-Qing; Liu, Wen-Bin

2017-09-01

A 8-week feeding trial was conducted to evaluate the effect of different berberine-dietary feeding modes on growth, non-specific immune responses and disease resistance of blunt snout bream, Megalobrama amblycephala. Fish (average initial weight 4.70 ± 0.02 g) were fed two fat levels (5% and 10%) diets in three berberine-feeding modes (supplementing 50 mg/kg berberine continuously, two-week or four-week intervals) with four replicates, respectively. Then, fish were challenged by Aeromonas hydrophila and mortality was recorded for the next 96 h after feeding trial. The results showed that different feeding modes of berberine significantly influenced growth, innate immunity and antioxidant capability of fish. Fish fed normal diet with 50 mg/kg berberine at two-week interval mode reflected remarkably (P < 0.05) high weight gain (WG). Plasma TC and TG contents were significantly (P < 0.05) decreased. The lysozyme (LYZ) activities, complement component 3 (C3) and complement component 4 (C4) concentrations were significantly (P < 0.05) increased. Fish not only exhibited relatively low hepatopancreas malondialdehyde (MDA) and lipid peroxide (LPO) contents, but also significantly (P < 0.05) improved superoxide dismutase (SOD) and catalase (CAT) activities. Fish mortality after challenged by Aeromonas hydrophila was decreased. Same results were also presented in fish fed high-fat diet with 50 mg/kg berberine at two-week, four-week intervals or continuous feeding modes. Based on fish healthy improvement and feeding cost saving, blunt snout bream fed normal diet with 50 mg/kg berberine at two-week interval or fed high-fat diet with berberine at two-week or four-week intervals were optimal feeding mode, respectively. Copyright © 2017. Published by Elsevier Ltd.

Control of foraging behavior of individuals within an ecosystem context: the clam Macoma balthica, flow environment, and siphon-cropping fishes.

PubMed

Peterson, Charles H; Skilleter, Gregory A

1994-12-01

Macoma balthica (L.), an abundant clam, ubiquitous in temperate estuaries across the North Atlantic, is known to practice both alternative basic modes of feeding available to seafloor invertebrates. It either holds its feeding organ, the siphon, at a fixed position just above the sediment surface to filter out food particles suspended in the overlying water or else extends and moves its siphon around to vacuum up deposited food particles on the sediment surface. Previous laboratory experiments have established an understanding of the role of current flow in dictating the choice of whether suspension or deposit feeding will be used by marine invertebrates with the facultative flexibility to choose. Faster flows imply greater fluxes of suspended particles so that the energetic rewards of suspension feeding are enhanced. Slower flows imply reduced renewal rates of suspended foods in the bottom boundary layers and enhanced deposition of food particles on the seafloor so that a switch to deposit feeding is favored. Like early optimal foraging theory, this understanding is based on energetic considerations alone without incorporation of broader implications of how population interactions such as predation and competition influence individual foraging behavior. Feeding behavior of Macoma balthica is influenced in the Neuse River estuary by both hydrodynamics and siphon-cropping by juvenile demersal fishes. Under conditions of identical concentrations of suspended particulates in the water column and organic contents of surface sediments, Macoma exhibited much higher levels of deposit feeding where currents were slower. In addition, exclosure and fish inclosure experiments demonstrated that juvenile demersal fishes influence feeding behavior of Macoma by cropping exposed siphons and inducing reduction in deposit-feeding activity. Effects of croppers were substantial in early to midsummer, when juvenile fish abundances were greatest in trawl samples from this estuarine nursery and before the growing fish exhibited ontogenetic changes in diet away from early concentration on bivalve siphons. Field experiments in which siphon-cropping fish were caged at varying distances off the bottom failed to detect any effective behavioral avoidance by Macoma of cropping in response to proximity of fish. One might have hypothesized that under high risk of cropping, Macoma would switch to suspension feeding and away from deposit feeding, the feeding method entailing more risk of losses to croppers because of greater siphon activity and greater extension of siphons on the sediment surface. Consequently, partial predation by siphon-cropping fishes greatly reduces deposit-feeding activity by Macoma balthica during summer as an apparent direct effect of disfigurement and reduction of siphons, the organ required for efficient deposit feeding. Information on current flows alone would not suffice to predict feeding behavior of this marine invertebrate: the influence of partial predation must also be included.

Evaluation of feed and feeding regime on growth performance, flesh quality and fecal viscosity of Atlantic salmon ( Salmo salar L.) in recirculating aquaculture systems

NASA Astrophysics Data System (ADS)

Sun, Guoxiang; Liu, Ying; Li, Yong; Li, Xian; Wang, Shunkui

2015-10-01

The effects of different feeds and feeding regimes on growth performance, flesh quality and fecal viscosity of Atlantic salmon ( Salmo salar L.) in recirculating aquaculture systems (RAS) were investigated. Fish (initial body weight of 1677 g ± 157 g) were fed with four commercial feeds (Nosan salmon-NS, Aller gold-AG, Skretting salmon-SS and Han ye-HY) in two feeding regimes (80% and 100% satiation) for 78 d. The results showed that salmon specific growth ratio (SGR) and weight gain ratio (WGR) were significantly affected by feed type and feeding regime ( P < 0.05). Feed conversion ratio (FCR) varied between 0.93 and 3.40, which was significantly affected by feed type ( P < 0.05), and slightly improved with increased satiation degree. The activities of digestive enzymes including protease, lipase and amylase were also significantly affected by feed type and feeding regime ( P < 0.05), increasing with satiation degree. Flesh qualities for vitamin E, hydroxyproline (HYP), liquid loss and muscle pH among all groups showed significant differences ( P < 0.05), ranging from 26.67 to 29.67, while no obvious difference was found in flesh color. Fecal viscosity for different treatments showed no significant difference, though improvement was found in 100% satiation group. From present experiment, it was concluded that both feed type and feeding regime can affect the important quality attributes of Atlantic salmon.

25 CFR 242.2 - Authority to engage in commercial fishing.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Authority to engage in commercial fishing. 242.2 Section 242.2 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE COMMERCIAL FISHING ON RED LAKE INDIAN RESERVATION § 242.2 Authority to engage in commercial fishing. No person shall...

36 CFR 13.1144 - How often will commercial fishing lifetime access permit be renewed?

Code of Federal Regulations, 2014 CFR

2014-07-01

... fishing lifetime access permit be renewed? 13.1144 Section 13.1144 Parks, Forests, and Public Property...-Glacier Bay National Park and Preserve Commercial Fishing § 13.1144 How often will commercial fishing... for the lifetime of a permittee who continues to hold a valid State limited entry commercial fishing...

36 CFR 13.1144 - How often will commercial fishing lifetime access permit be renewed?

Code of Federal Regulations, 2012 CFR

2012-07-01

... fishing lifetime access permit be renewed? 13.1144 Section 13.1144 Parks, Forests, and Public Property...-Glacier Bay National Park and Preserve Commercial Fishing § 13.1144 How often will commercial fishing... for the lifetime of a permittee who continues to hold a valid State limited entry commercial fishing...

36 CFR 13.1144 - How often will commercial fishing lifetime access permit be renewed?

Code of Federal Regulations, 2011 CFR

2011-07-01

... fishing lifetime access permit be renewed? 13.1144 Section 13.1144 Parks, Forests, and Public Property...-Glacier Bay National Park and Preserve Commercial Fishing § 13.1144 How often will commercial fishing... for the lifetime of a permittee who continues to hold a valid State limited entry commercial fishing...

36 CFR 13.1132 - What types of commercial fishing are authorized in Glacier Bay?

Code of Federal Regulations, 2014 CFR

2014-07-01

... fishing are authorized in Glacier Bay? 13.1132 Section 13.1132 Parks, Forests, and Public Property...-Glacier Bay National Park and Preserve Commercial Fishing § 13.1132 What types of commercial fishing are authorized in Glacier Bay? Three types of commercial fishing are authorized in Glacier Bay non-wilderness...

36 CFR 13.1132 - What types of commercial fishing are authorized in Glacier Bay?

Code of Federal Regulations, 2011 CFR

2011-07-01

... fishing are authorized in Glacier Bay? 13.1132 Section 13.1132 Parks, Forests, and Public Property...-Glacier Bay National Park and Preserve Commercial Fishing § 13.1132 What types of commercial fishing are authorized in Glacier Bay? Three types of commercial fishing are authorized in Glacier Bay non-wilderness...

36 CFR 13.1132 - What types of commercial fishing are authorized in Glacier Bay?

Code of Federal Regulations, 2012 CFR

2012-07-01

... fishing are authorized in Glacier Bay? 13.1132 Section 13.1132 Parks, Forests, and Public Property...-Glacier Bay National Park and Preserve Commercial Fishing § 13.1132 What types of commercial fishing are authorized in Glacier Bay? Three types of commercial fishing are authorized in Glacier Bay non-wilderness...

Zearalenone (ZEN) and Its Influence on Regulation of Gene Expression in Carp (Cyprinus carpio L.) Liver Tissue

PubMed Central

Pietsch, Constanze

2017-01-01

Zearalenone (ZEN) is a frequently-occurring mycotoxin in both animal and fish feeds. In order to characterize its effects on carp, three groups of fish were fed for 28 days with feeds contaminated with three different levels of ZEN (low: 332 µg kg−1, medium: 621 µg kg−1, and high: 797 µg kg−1 feed). The reversibility of the effects of ZEN was assessed by feeding all of the groups with uncontaminated feed for a further 14 days. Gene expression of immune genes in the liver tissue of the fish was analysed, revealing reduced expressions of immune, antioxidative, and estrogen-related genes after the fish had been exposed to ZEN. However, the expression of vacuole-type H+ ATPase increased substantially with ZEN exposure, thus supporting the previously-reported sensitivity of lysosomal functions to ZEN. Feeding the fish with a ZEN-free diet for a further two weeks changed the effects of ZEN on the expression of some genes, including the expressions of the cytokines IL-1β, IL-8, IL-10, and arginase 2, which were not influenced after four weeks of treatment, but showed lower values after the recovery phase in fish previously treated with ZEN compared with the control group. In summary, this study confirmed the broad effects of ZEN on different essential functions in carp and suggests that the current maximum allowable levels in compound feed are too high to prevent damage to fish. PMID:28914814

Zearalenone (ZEN) and Its Influence on Regulation of Gene Expression in Carp (Cyprinus carpio L.) Liver Tissue.

PubMed

Pietsch, Constanze

2017-09-15

Zearalenone (ZEN) is a frequently-occurring mycotoxin in both animal and fish feeds. In order to characterize its effects on carp, three groups of fish were fed for 28 days with feeds contaminated with three different levels of ZEN (low: 332 µg kg -1 , medium: 621 µg kg -1 , and high: 797 µg kg -1 feed). The reversibility of the effects of ZEN was assessed by feeding all of the groups with uncontaminated feed for a further 14 days. Gene expression of immune genes in the liver tissue of the fish was analysed, revealing reduced expressions of immune, antioxidative, and estrogen-related genes after the fish had been exposed to ZEN. However, the expression of vacuole-type H⁺ ATPase increased substantially with ZEN exposure, thus supporting the previously-reported sensitivity of lysosomal functions to ZEN. Feeding the fish with a ZEN-free diet for a further two weeks changed the effects of ZEN on the expression of some genes, including the expressions of the cytokines IL-1β, IL-8, IL-10, and arginase 2, which were not influenced after four weeks of treatment, but showed lower values after the recovery phase in fish previously treated with ZEN compared with the control group. In summary, this study confirmed the broad effects of ZEN on different essential functions in carp and suggests that the current maximum allowable levels in compound feed are too high to prevent damage to fish.

Effects of feeding regimes and early maturation on migratory behaviour of landlocked hatchery-reared Atlantic salmon Salmo salar smolts.

PubMed

Norrgård, J R; Bergman, E; Schmitz, M; Greenberg, L A

2014-10-01

The migratory behaviour of hatchery-reared landlocked Atlantic salmon Salmo salar raised under three different feeding regimes was monitored through the lower part of the River Klarälven, Sweden. The smolts were implanted with acoustic transmitters and released into the River Klarälven, 25 km upstream of the outlet in Lake Vänern. Early mature males, which had matured the previous autumn, were also tagged and released. To monitor migration of the fish, acoustic receivers were deployed along the migratory route. The proportion of S. salar that reached Lake Vänern was significantly greater for fish fed fat-reduced feed than for fish given rations with higher fat content, regardless of ration size. Fish from the early mature male group remained in the river to a greater extent than fish from the three feeding regimes. Smolt status (degree of silvering), as visually assessed, did not differ among the feeding regime groups, and moreover, fully-silvered fish, regardless of feeding regime, migrated faster and had a greater migration success than fish with less developed smolt characteristics. Also, successful migrants had a lower condition factor than unsuccessful ones. These results indicate that the migration success of hatchery-reared S. smolts released to the wild can be enhanced by relatively simple changes in feeding regimes and by matching stocking time with smolt development. © 2014 The Fisheries Society of the British Isles.

50 CFR 216.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

.... Commercial fishing operation means the lawful harvesting of fish from the marine environment for profit as part of an ongoing business enterprise. Such terms may include licensed commercial passenger fishing... are subsequently sold. Commercial passenger fishing vessel means any vessel licensed for commercial...

50 CFR 216.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

.... Commercial fishing operation means the lawful harvesting of fish from the marine environment for profit as part of an ongoing business enterprise. Such terms may include licensed commercial passenger fishing... are subsequently sold. Commercial passenger fishing vessel means any vessel licensed for commercial...

50 CFR 216.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

.... Commercial fishing operation means the lawful harvesting of fish from the marine environment for profit as part of an ongoing business enterprise. Such terms may include licensed commercial passenger fishing... are subsequently sold. Commercial passenger fishing vessel means any vessel licensed for commercial...

50 CFR 216.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

.... Commercial fishing operation means the lawful harvesting of fish from the marine environment for profit as part of an ongoing business enterprise. Such terms may include licensed commercial passenger fishing... are subsequently sold. Commercial passenger fishing vessel means any vessel licensed for commercial...

50 CFR 216.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

.... Commercial fishing operation means the lawful harvesting of fish from the marine environment for profit as part of an ongoing business enterprise. Such terms may include licensed commercial passenger fishing... are subsequently sold. Commercial passenger fishing vessel means any vessel licensed for commercial...

Mercury exposure and source tracking in distinct marine-caged fish farm in southern China.

PubMed

Xu, Xiaoyu; Wang, Wen-Xiong

2017-01-01

Coasts of South China have experienced an unprecedented growth in its marine-caged fish industry. We analyzed mercury concentrations and stable mercury isotope ratios in fourteen fish species from two cage-cultured farms in Southern China. Total mercury concentrations of all species were lower than the human health screening values, but the human exposures through consumption of several carnivorous fish exceeded the USEPA's reference dose. Isotopic compositions in the sediment (δ 202 Hg: -1.45‰ to -1.23‰; Δ 199 Hg: -0.04‰ to -0.01‰) suggested that mercury in these farms were from coal combustion and industrial inputs. Commercial food pellets and fresh fish viscera provided the major sources of methylmercury to the farmed fish and dominated their mercury isotopic signatures. Non-carnivorous fish presented lower δ 202 Hg and Δ 199 Hg values than the carnivorous fish. Using a mixing model, we demonstrated that the majority of mercury in non-carnivorous species came from pellets and in carnivorous fish came from combined diets of pellets and viscera. Meanwhile, methylmercury concentrations and % methylmercury in the fish were positively correlated with δ 202 Hg values but not with Δ 199 Hg values, mainly because fish eating similar feeds maintained similar Δ 199 Hg values. Environmental influences of cage farming such as fish feces and uneaten viscera that continuously provide organic mercury to the environments need to be considered. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of riparian forest removal on the trophic dynamics of a Neotropical stream fish assemblage.

PubMed

Lobón-Cerviá, J; Mazzoni, R; Rezende, C F

2016-07-01

The effects of riparian forest removal on a neotropical stream fish assemblage were assessed in the Mata Atlântica. Fish assemblage structure and fish feeding patterns were quantified at three sites along a pristine-to-deforested gradient in a Serra do Mar stream: (1) a pristine site fully covered by canopy with no light penetration and transparent waters, (2) an intermediate site with partially removed forest and (3) a fully removed forest site with no canopy and full light penetration where siltation and turbid waters predominate. Fish assemblage structure, fish densities and their feeding patterns differed widely among sites. Whilst the same five fish species occurred at the three sites, forest removal favoured the occurrence of sediment-tolerant iliophagous benthic species at the deforested site. At the pristine site, invertebrate prey predominated in water column fish diet and feeding overlap among species was low. Severe shifts in the feeding patterns were noticed in both deforested sites. Invertebrates were replaced by detritus, organic matter and algae at both sites and feeding overlap increased markedly. The overwhelming feeding adaptability of these neotropical fishes appeared capable of buffering the deleterious effects of forest removal on stream quality in terms of increased light penetration, siltation and water turbidity. Forest cutting in this Mata Atlântica stream clearly caused strong functional changes associated with forest clearance through important modifications in the assemblage organization and trophic patterns of the main species, but did not eliminate species. © 2016 The Fisheries Society of the British Isles.

Evaluation of PCDD/Fs characterization in animal feed and feed additives.

PubMed

Kim, MeeKyung; Kim, Sooyeon; Yun, Seon Jong; Kwon, Jin-Wook; Son, Seong-Wan

2007-09-01

Safety control of feed and feed additives is necessary to have safe food of animal origin. Based on media reports, nine incidents regarding dioxins and/or PCBs contaminations occurred worldwide during the last decade. Korea is a country which imports feed and feed additives. In this study, various kinds of feed and feed additives were analyzed to monitor the contamination level of dioxins. The level of PCDD/Fs in fish oil was the highest with a concentration of 23.33ngkg(-1), which is equivalent to a toxicological concentration of 4.68ngWHO-TEQ/kg. Feed from animals origin such as chicken meal, animal fat, fish meal, fish oil, and shell powder showed relatively higher concentrations of PCDD/Fs. Feed from plants origin, minerals, and additives ranged from non-detects for bit pulp and ethoxyquin to 8.28ngkg(-1) for dl-methionine. From a toxicological point of view, the highest concentration in vitamins was 0.08ngWHO-TEQ/kg among the feed additives. 2,3,4,7,8-PeCDF was the dominant congener in samples of fish oil, fish meal, and shell powder. Animal fat showed that the pattern of PCDD/Fs depends on the sources of contamination. A sample of animal fat showed 1,2,3,4,7,8-HxCDF and the other sample showed 1,2,3,4,7,8-HxCDD as a primary congener. Generally, low levels of PCDDs were detected in feed additives. Patterns of PCDD/Fs in choline chloride were different with that in choline chloride from an incident in Europe in 2000.

Determining Suction Feeding Efficiency in the Bowfin fish (Amia) using Particle Image Velocimery and Computaional Fluid Dynamics

NASA Astrophysics Data System (ADS)

Rua, Yenny; Kharbouch, Karim; Sanford, Christopher; Reckinger, Shanon

2014-11-01

Suction feeding is the most common form of prey capture in aquatic vertebrates. During the early evolution of fishes there was a major change in shape of the mouth, from a wedge shaped mouth opening in more primitive fishes to a more circular and planar mouth. This change in shape resulted from increased mobility of a key upper jaw bone, the maxilla. It has been suggested that this change in shape dramatically increased suction feeding efficiency. This study examines the hydrodynamic effects of these two mouth shapes in the same animal, the bowfin fish (Amia calva). 2D Particle Image Velocimetry (PIV) is used to analyze suction feeding events. Post-processing algorithms have been developed to determine the flow rate of water into the mouth of the fish; the area of fluid, the velocity of fluid and the volume of fluid affected by the fish; the velocity of the fluid at the mouth, as well as the velocity of the fluid as a function of the distance from the mouth, finally the force exerted on the fluid by the fish is also determined. Lastly, a numerical model has been developed for comparison using a non-uniform mesh, which adapts dynamically in space and time to the fish feeding event. The realistic geometry of the fish's head is modeled in CAD.

Preliminary Validation of a High Docosahexaenoic Acid (DHA) and -Linolenic Acid (ALA) Dietary Oil Blend: Tissue Fatty Acid Composition and Liver Proteome Response in Atlantic Salmon (Salmo salar) Smolts

PubMed Central

Nuez-Ortín, Waldo G.; Carter, Chris G.; Wilson, Richard; Cooke, Ira; Nichols, Peter D.

2016-01-01

Marine oils are important to human nutrition as the major source of docosahexaenoic acid (DHA), a key omega-3 long-chain (≥C20) polyunsaturated fatty acid (n-3 LC-PUFA) that is low or lacking in terrestrial plant or animal oils. The inclusion of fish oil as main source of n-3 LC-PUFA in aquafeeds is mostly limited by the increasing price and decreasing availability. Fish oil replacement with cheaper terrestrial plant and animal oils has considerably reduced the content of n-3 LC-PUFA in flesh of farmed Atlantic salmon. Novel DHA-enriched oils with high alpha-linolenic acid (ALA) content will be available from transgenic oilseeds plants in the near future as an alternative for dietary fish oil replacement in aquafeeds. As a preliminary validation, we formulated an oil blend (TOFX) with high DHA and ALA content using tuna oil (TO) high in DHA and the flaxseed oil (FX) high in ALA, and assessed its ability to achieve fish oil-like n-3 LC-PUFA tissue composition in Atlantic salmon smolts. We applied proteomics as an exploratory approach to understand the effects of nutritional changes on the fish liver. Comparisons were made between fish fed a fish oil-based diet (FO) and a commercial-like oil blend diet (fish oil + poultry oil, FOPO) over 89 days. Growth and feed efficiency ratio were lower on the TOFX diet. Fish muscle concentration of n-3 LC-PUFA was significantly higher for TOFX than for FOPO fish, but not higher than for FO fish, while retention efficiency of n-3 LC-PUFA was promoted by TOFX relative to FO. Proteomics analysis revealed an oxidative stress response indicative of the main adaptive physiological mechanism in TOFX fish. While specific dietary fatty acid concentrations and balances and antioxidant supplementation may need further attention, the use of an oil with a high content of DHA and ALA can enhance tissue deposition of n-3 LC-PUFA in relation to a commercially used oil blend. PMID:27556399

Preliminary Validation of a High Docosahexaenoic Acid (DHA) and -Linolenic Acid (ALA) Dietary Oil Blend: Tissue Fatty Acid Composition and Liver Proteome Response in Atlantic Salmon (Salmo salar) Smolts.

PubMed

Nuez-Ortín, Waldo G; Carter, Chris G; Wilson, Richard; Cooke, Ira; Nichols, Peter D

2016-01-01

Marine oils are important to human nutrition as the major source of docosahexaenoic acid (DHA), a key omega-3 long-chain (≥C20) polyunsaturated fatty acid (n-3 LC-PUFA) that is low or lacking in terrestrial plant or animal oils. The inclusion of fish oil as main source of n-3 LC-PUFA in aquafeeds is mostly limited by the increasing price and decreasing availability. Fish oil replacement with cheaper terrestrial plant and animal oils has considerably reduced the content of n-3 LC-PUFA in flesh of farmed Atlantic salmon. Novel DHA-enriched oils with high alpha-linolenic acid (ALA) content will be available from transgenic oilseeds plants in the near future as an alternative for dietary fish oil replacement in aquafeeds. As a preliminary validation, we formulated an oil blend (TOFX) with high DHA and ALA content using tuna oil (TO) high in DHA and the flaxseed oil (FX) high in ALA, and assessed its ability to achieve fish oil-like n-3 LC-PUFA tissue composition in Atlantic salmon smolts. We applied proteomics as an exploratory approach to understand the effects of nutritional changes on the fish liver. Comparisons were made between fish fed a fish oil-based diet (FO) and a commercial-like oil blend diet (fish oil + poultry oil, FOPO) over 89 days. Growth and feed efficiency ratio were lower on the TOFX diet. Fish muscle concentration of n-3 LC-PUFA was significantly higher for TOFX than for FOPO fish, but not higher than for FO fish, while retention efficiency of n-3 LC-PUFA was promoted by TOFX relative to FO. Proteomics analysis revealed an oxidative stress response indicative of the main adaptive physiological mechanism in TOFX fish. While specific dietary fatty acid concentrations and balances and antioxidant supplementation may need further attention, the use of an oil with a high content of DHA and ALA can enhance tissue deposition of n-3 LC-PUFA in relation to a commercially used oil blend.

Engineering Support for the Development of a Submersible Fish Cage for Open Ocean Aquaculture

DTIC Science & Technology

2007-01-01

32 Appendix B: Feed Hose Buoy Components ................................................................. 33...ballasting systems (for test purposes) located in the upper rim section and airlift. Another component of the system includes a feed hose buoy used...to deliver pellets to fish in the cage while the system is submerged. Since the feed hose buoy was not critical in the development of the fish

The distribution and abundance of reef-associated predatory fishes on the Great Barrier Reef

NASA Astrophysics Data System (ADS)

Emslie, Michael J.; Cheal, Alistair J.; Logan, Murray

2017-09-01

Predatory fishes are important components of coral-reef ecosystems of the Great Barrier Reef (GBR) through both the ecological functions they perform and their high value to recreational and commercial fisheries, estimated at 30 million in 2014. However, management of GBR predatory fish populations is hampered by a lack of knowledge of their distribution and abundance, aside from that of the highly targeted coral trout ( Plectropomus spp. and Variola spp.). Furthermore, there is little information on how these fishes respond to environmental stressors such as coral bleaching, outbreaks of coral-feeding starfishes ( Acanthaster planci) and storms, which limits adaptive management of their populations as the frequency or severity of such natural disturbances increases under climate change. Here, we document the distribution and abundance of 48 species of reef-associated predatory fishes and assess their vulnerability to a range of natural disturbances. There were clear differences in predatory fish assemblages across the continental shelf, but many species were widespread, with few species restricted to either inshore or offshore waters. There was weak latitudinal structure with only a few species restricted to either the northern or southern GBR. On the whole, predatory fishes were surprisingly resistant to the effects of disturbance, with few clear changes in abundance or species richness following 66 documented disturbances of varying magnitudes.

Tracking pollutants in dietary fish oil: From ocean to table.

PubMed

Sun, Sheng-Xiang; Hua, Xue-Ming; Deng, Yun-Yun; Zhang, Yun-Ni; Li, Jia-Min; Wu, Zhao; Limbu, Samwel Mchele; Lu, Da-Sheng; Yin, Hao-Wen; Wang, Guo-Quan; Waagbø, Rune; Livar, Frøyland; Zhang, Mei-Ling; Du, Zhen-Yu

2018-05-16

Dietary fish oil used in aquafeed transfers marine pollutants to farmed fish. However, the entire transfer route of marine pollutants in dietary fish oil from ocean to table fish has not been tracked quantitatively. To track the entire transfer route of marine pollutants from wild fish to farmed fish through dietary fish oil and evaluate the related human health risks, we obtained crude and refined fish oils originating from the same batch of wild ocean anchovy and prepared fish oil-containing purified aquafeeds to feed omnivorous lean Nile tilapia and carnivorous fatty yellow catfish for eight weeks. The potential human health risk of consumption of these fish was evaluated. Marine persistent organic pollutants (POPs) were concentrated in fish oil, but were largely removed by the refining process, particularly dioxins and polychlorinated biphenyls (PCBs). The differences in the POP concentrations between crude and refined fish oils were retained in the fillets of the farmed fish. Fillets fat content and fish growth were positively and negatively correlated to the final POPs deposition in fillets, respectively. The retention rates of marine POPs in the final fillets through fish oil-contained aquafeeds were 1.3%-5.2%, and were correlated with the POPs concentrations in feeds and fillets, feed utilization and carcass ratios. The dietary crude fish oil-contained aquafeeds are a higher hazard ratio to consumers. Prohibiting the use of crude fish oil in aquafeed and improving growth and feed efficiency in farmed fish are promising strategies to reduce health risks originating from marine POPs. Copyright © 2018 Elsevier Ltd. All rights reserved.

A vegetable oil feeding history affects digestibility and intestinal fatty acid uptake in juvenile rainbow trout Oncorhynchus mykiss.

PubMed

Geurden, Inge; Jutfelt, Fredrik; Olsen, Rolf-Erik; Sundell, Kristina S

2009-04-01

Future expansion of aquaculture relies on the use of alternatives to fish oil in fish feed. This study examined to what extent the nature of the feed oil affects intestinal lipid uptake properties in rainbow trout. The fish were fed a diet containing fish (FO), rapeseed (RO) or linseed (LO) oil for 8 weeks after which absorptive properties were assessed. Differences in digestibility due to feed oil history were measured using diet FO with an indigestible marker. Intestinal integrity, paracellular permeability, in vitro transepithelial fatty acid transport (3H-18:3n-3 and 14C-16:0) and their incorporation into intestinal epithelia were compared using Ussing chambers. Feed oil history did not affect the triacylglycerol/phosphatidylcholine ratio (TAG/PC) of the newly synthesized lipids in the segments. The lower TAG/PC ratio with 16:0 (2:1) than with 18:3 (10:1) showed the preferential incorporation of 16:0 into polar lipids. The FO-feeding history decreased permeability and increased transepithelial resistance of the intestinal segments. Transepithelial passage rates of 18:3n-3 were higher when pre-fed LO compared to RO or FO. Similarly, pre-feeding LO increased apparent lipid and fatty acid digestibilities compared to RO or FO. These results demonstrate that the absorptive intestinal functions in fish can be altered by the feed oil history and that the effect remains after a return to a standard fish oil diet.

GSM Web-Based Centralized Remote Wireless Automatic Controlling and Monitoring of Aquafeeder

NASA Astrophysics Data System (ADS)

Wong, C. L.; Idris, A.; Hasan, Z.

2016-03-01

This project is about producing a prototype to feed fishes at fish ponds of remote location with the use of GSM mobile phone. An automatic fish feeder is an electric device that has been designed to give out the right amount of pellets at the designed time. In this project, the automatic feeder designed consists of photovoltaic solar cells that are used to generate electricity and storing it into batteries. Solar charge controllers can be used to determine the rate of which current is drawn and added from the batteries. GSM cellular communication is used to allow user to control from a distance. Commands or instructions are sent to the operating system which in return runs the servomotor and blower by blowing certain amount of fish pallets into the pond to feed the fishes. The duration of the feeding processes is fixed by the user, hence the amount of fish food pallets released are precisely the same for each time. This technology is especially useful for fish farmers where they can remotely feed their fishes.

25 CFR 242.2 - Authority to engage in commercial fishing.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 25 Indians 1 2014-04-01 2014-04-01 false Authority to engage in commercial fishing. 242.2 Section... FISHING ON RED LAKE INDIAN RESERVATION § 242.2 Authority to engage in commercial fishing. No person shall engage in commercial fishing in the waters of the Red Lakes on the Red Lake Indian Reservation in the...

25 CFR 242.2 - Authority to engage in commercial fishing.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 25 Indians 1 2012-04-01 2011-04-01 true Authority to engage in commercial fishing. 242.2 Section... FISHING ON RED LAKE INDIAN RESERVATION § 242.2 Authority to engage in commercial fishing. No person shall engage in commercial fishing in the waters of the Red Lakes on the Red Lake Indian Reservation in the...

25 CFR 242.2 - Authority to engage in commercial fishing.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 25 Indians 1 2011-04-01 2011-04-01 false Authority to engage in commercial fishing. 242.2 Section... FISHING ON RED LAKE INDIAN RESERVATION § 242.2 Authority to engage in commercial fishing. No person shall engage in commercial fishing in the waters of the Red Lakes on the Red Lake Indian Reservation in the...

25 CFR 242.2 - Authority to engage in commercial fishing.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 25 Indians 1 2013-04-01 2013-04-01 false Authority to engage in commercial fishing. 242.2 Section... FISHING ON RED LAKE INDIAN RESERVATION § 242.2 Authority to engage in commercial fishing. No person shall engage in commercial fishing in the waters of the Red Lakes on the Red Lake Indian Reservation in the...

Effect of microalgae on intestinal inflammation triggered by soybean meal and bacterial infection in zebrafish

PubMed Central

Solís, Camila J.; Ulloa, Pilar E.; Hedrera, Manuel; Pizarro-Guajardo, Marjorie; Paredes-Sabja, Daniel

2017-01-01

Soybean meal has been used in many commercial diets for farm fish; despite this component inducing intestinal inflammation. On the other hand, microalgae have increasingly been used as dietary supplements in fish feed. Nevertheless, the vast quantity of microalgae species means that many remain under- or unstudied, thus limiting wide scale commercial application. In this work, we evaluated the effects to zebrafish (Danio rerio) of including Tetraselmis sp (Ts); Phaeodactylum tricornutum (Pt); Chlorella sp (Ch); Nannochloropsis oculata (No); or Nannochloropsis gaditana (Ng) as additives in a soybean meal-based diet on intestinal inflammation and survival after Edwardsiella tarda infection. In larvae fed a soybean meal diet supplemented with Ts, Pt, Ch, or Ng, the quantity of neutrophils present in the intestine drastically decreased as compared to larvae fed only the soybean meal diet. Likewise, Ts or Ch supplements in soybean meal or fishmeal increased zebrafish survival by more than 20% after being challenged. In the case of Ts, the observed effect correlated with an increased number of neutrophils present at the infection site. These results suggest that the inclusion of Ts or Ch in fish diets could allow the use of SBM and at the same time improve performance against pathogen. PMID:29117213

Fatty Acid Composition and Contents of Seven Commercial Fish Species of Genus Coregonus from Russian Subarctic Water Bodies.

PubMed

Gladyshev, Michail I; Sushchik, Nadezhda N; Makhutova, Olesia N; Glushchenko, Larisa A; Rudchenko, Anastasia E; Makhrov, Alexander A; Borovikova, Elena A; Dgebuadze, Yury Y

2017-12-01

In several Russian northern lakes and rivers, Arctic cisco Coregonus autumnalis, least cisco C. sardinella, peled C. peled, tugun C. tugun, broad whitefish C. nasus, whitefish C. lavaretus and vendace C. albula were sampled in periods of officially permitted commercial fishery. Special attention was paid to contents (mg g -1 of wet weight) of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in muscle tissues (filets), which are essential for human nutrition. The highest values of EPA + DHA content in semi-anadromous fish and freshwater fish were recorded for C. autumnalis from the Yenisei River, 17.60 mg g -1 wet weight, and for C. lavaretus from the Sobachye Lake, 16.61 mg g -1 wet weight, respectively. Intra-genus variations of EPA + DHA contents of Coregonus species were from 1.87 to 17.60 mg g -1 wet weight. Since the congeneric species were genetically close to each other, the variations in EPA and DHA contents were thought to be caused primarily by ecological factors: migrational capability, type of feeding and trophic status of aquatic ecosystems. In general, the majority of studied species appeared to be of a high nutritive value for humans, although unfavorable environmental conditions could considerably diminish this value.

Towards Sustainable Aquafeeds: Complete Substitution of Fish Oil with Marine Microalga Schizochytrium sp. Improves Growth and Fatty Acid Deposition in Juvenile Nile Tilapia (Oreochromis niloticus).

PubMed

Sarker, Pallab K; Kapuscinski, Anne R; Lanois, Alison J; Livesey, Erin D; Bernhard, Katie P; Coley, Mariah L

2016-01-01

We conducted a 84-day nutritional feeding experiment with dried whole cells of DHA-rich marine microalga Schizochytrium sp. (Sc) to determine the optimum level of fish-oil substitution (partial or complete) for maximum growth of Nile tilapia. When we fully replaced fish oil with Schizochytrium (Sc100 diet), we found significantly higher weight gain and protein efficiency ratio (PER), and lower (improved) feed conversion ratio (FCR) and feed intake compared to a control diet containing fish oil (Sc0); and no significant change in SGR and survival rate among all diets. The Sc100 diet had the highest contents of 22:6n3 DHA, led to the highest DHA content in fillets, and consequently led to the highest DHA:EPA ratios in tilapia fillets. Schizochytrium sp. is a high quality candidate for complete substitution of fish oil in juvenile Nile tilapia feeds, providing an innovative means to formulate and optimize the composition of tilapia juvenile feed while simultaneously raising feed efficiency of tilapia aquaculture and to further develop environmentally and socially sustainable aquafeeds. Results show that replacing fish oil with DHA-rich marine Sc improves the deposition of n3 LC PUFA levels in tilapia fillet. These results support further studies to lower Schizochytrium production costs and to combine different marine microalgae to replace fish oil and fishmeal into aquafeeds.

Dietary calcein marking of brook trout, Atlantic salmon, yellow perch, and coho salmon scales

USGS Publications Warehouse

Honeyfield, D.C.; Ostrowski, C.S.; Fletcher, J.W.; Mohler, J.W.

2006-01-01

Brook trout Salvelinus fontinalis, Atlantic salmon Salmo salar, coho salmon Oncorhynchus kisutch, and yellow perch Perca flavescens fed calcein for 5 d showed characteristic calcein scale marks 7-10 d postmarking. In fish fed 0.75 or 1.25 g of calcein per kilogram of feed, the percentage of fish that exhibited a calcein mark was 100% in brook trout, 93-98% in Atlantic salmon, 60% in yellow perch, and 0% in coho salmon. However, when coho salmon were fed 5.25 g calcein/kg feed, 100% marking was observed 7-10 d postmarking. Brook trout were successfully marked twice with distinct bands when fed calcein 5 months apart. Brook trout scale pixel luminosity increased as dietary calcein increased in experiment 2. For the second calcein mark, scale pixel luminosity from brook trout fed 1.25 g calcein/kg feed was numerically higher (P < 0.08) than scales from fish fed 0.75 g calcein/kg feed. Mean pixel luminosity of calcein-marked Atlantic salmon scales was 57.7 for fish fed 0.75 g calcein/kg feed and 55.2 for fish fed 1.25 g calcein/kg feed. Although feed acceptance presented a problem in yellow perch, these experiments provide evidence that dietary calcein is a viable tool for marking fish for stock identification. ?? Copyright by the American Fisheries Society 2006.

75 FR 14609 - Commercial Fishing Industry Vessel Safety Advisory Committee; Vacancies

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-26

... DEPARTMENT OF HOMELAND SECURITY Coast Guard [Docket No. USCG-2010-0163] Commercial Fishing... applications. SUMMARY: The Coast Guard seeks applications for membership on the Commercial Fishing Industry... Coast Guard on matters relating to the safe operation of commercial fishing industry vessels. DATES...

36 CFR 13.1144 - How often will commercial fishing lifetime access permit be renewed?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false How often will commercial...-Glacier Bay National Park and Preserve Commercial Fishing § 13.1144 How often will commercial fishing... for the lifetime of a permittee who continues to hold a valid State limited entry commercial fishing...

Comparison of remote video and diver's direct observations to quantify reef fishes feeding on benthos in coral and rocky reefs.

PubMed

Longo, G O; Floeter, S R

2012-10-01

This study compared remote underwater video and traditional direct diver observations to assess reef fish feeding impact on benthos across multiple functional groups within different trophic categories (e.g. herbivores, zoobenthivores and omnivores) and in two distinct reef systems: a subtropical rocky reef and a tropical coral reef. The two techniques were roughly equivalent, both detecting the species with higher feeding impact and recording similar bite rates, suggesting that reef fish feeding behaviour at the study areas are not strongly affected by the diver's presence. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

Daily rhythms of locomotor and demand-feeding activities in Schizothorax pelzami (Kessler, 1870).

PubMed

Ebrahimi, Ehsan; Kamrani, Ehsan; Heydarnejad, Mohammad Saeed; Safari, Omid

2017-01-01

A study was carried out to investigate the daily rhythms of locomotor and feeding activity of Khajoo, Schizothorax pelzami, a candidate species for freshwater aquaculture. Using self-feeder juvenile Khajoo were exposed to a 12/12 LD cycle to determine the rhythms of locomotor and feeding activity. The effects of feeding on locomotor and feeding activity of fish were also examined. Finally, the endogenous rhythmicity under different lighting condition tested. Fish displayed a strictly diurnal feeding and locomotor activities with 98% and 84% of the total activity occurred in the photophase, respectively. In scheduled feeding, both the L-group (fed in light) and the D-group (fed in the dark) showed a diurnal locomotor activity pattern. However, the L-group had a peak of locomotor activity near the feeding time, but the D-group had a scarce locomotor activity in the scatophase with no significant change at the mealtime. Most of the individuals display free-running rhythms when exposed to different lighting condition including, constant darkness, ultradian 45:45 min LD cycle and reversed DL photo cycle. Taken together the results of this study showed that both locomotor and feeding activity have diurnal rhythms in Khajoo S. pelzami, even fish feeding had taken place at night. Additionally, the free-running locomotor activity of the fish in the absence of external light stimuli, suggests the existence of an endogenous timing mechanism in this fish species.

LC-MS/MS methods for albendazole analysis in feed and its metabolite residues in fish fillet and a leaching study in feed after an alternative procedure for drug incorporation.

PubMed

Busatto, Zenaís; da Silva, Agnaldo Fernando Baldo; de Freitas, Osvaldo; Paschoal, Jonas Augusto Rizzato

2017-04-01

This paper describes the development of analytical methods for the quantification of albendazole (ABZ) in fish feed and ABZ and its main known metabolites (albendazole sulfoxide, albendazole sulfone and albendazole aminosulfone) in fish fillet employing LC-MS/MS. In order to assess the reliability of the analytical methods, evaluation was undertaken as recommended by related guides proposed by the Brazilian Ministry of Agriculture for analytical method validation. The calibration curve for ABZ quantification in feed showed adequate linearity (r > 0.99), precision (CV < 1.03%) and trueness ranging from 99% to 101%. The method for ABZ residues in fish fillet involving the QuEChERS technique for sample extraction had adequate linearity (r > 0.99) for all analytes, precision (CV < 13%) and trueness around 100%, with CCα < 122 ng g - 1 and CCβ < 145 ng g - 1 . Besides, by aiming to avoid the risk of ABZ leaching from feed into the aquatic environment during fish medication via the oral route, a promising procedure for drug incorporation in the feed involving coating feed pellets with ethyl cellulose polymer containing ABZ was also evaluated. The medicated feed had good homogeneity (CV < 3%) and a lower release of ABZ (< 0.2%) from feed to water when the medicated feed stayed in the water for up to 15 min.

Biosecurity Conditions in Small Commercial Chicken Farms, Bangladesh 2011–2012

PubMed Central

Rimi, N. A.; Sultana, R.; Muhsina, M.; Uddin, B.; Haider, N.; Nahar, N.; Zeidner, N.; Sturm-Ramirez, K.; Luby, S. P.

2018-01-01

In Bangladesh, highly pathogenic avian influenza H5N1 is endemic in poultry. This study aimed to understand the biosecurity conditions and farmers’ perception of avian influenza biosecurity in Bangladeshi small commercial chicken farms. During 2011–2012, we conducted observations, in-depth interviews and group discussions with poultry farmers in 16 farms and in-depth interviews with seven local feed vendors from two districts. None of the farms were completely segregated from people, backyard poultry, other animals, households, other poultry farms or large trees. Wild birds and rodents accessed the farms for poultry feed. Farmers usually did not allow the buyers to bring egg trays inside their sheds. Spraying disinfectant in the shed and removing feces were the only regular cleaning and disinfection activities observed. All farmers sold or used untreated feces as fish feed or fertilizer. Farmers were more concerned about Newcastle disease and infectious bursal disease than about avian influenza. Farmers’ understanding about biosecurity and avian influenza was influenced by local vendors. While we seldom observed flock segregation, some farmers used measures that involved additional cost or effort to protect their flocks. These farmers could be motivated by interventions to protect their investment from diseases they consider harmful. Future interventions could explore the feasibility and effectiveness of low-cost alternative biosecurity measures. PMID:28289988

Biosecurity Conditions in Small Commercial Chicken Farms, Bangladesh 2011-2012.

PubMed

Rimi, N A; Sultana, R; Muhsina, M; Uddin, B; Haider, N; Nahar, N; Zeidner, N; Sturm-Ramirez, K; Luby, S P

2017-06-01

In Bangladesh, highly pathogenic avian influenza H5N1 is endemic in poultry. This study aimed to understand the biosecurity conditions and farmers' perception of avian influenza biosecurity in Bangladeshi small commercial chicken farms. During 2011-2012, we conducted observations, in-depth interviews and group discussions with poultry farmers in 16 farms and in-depth interviews with seven local feed vendors from two districts. None of the farms were completely segregated from people, backyard poultry, other animals, households, other poultry farms or large trees. Wild birds and rodents accessed the farms for poultry feed. Farmers usually did not allow the buyers to bring egg trays inside their sheds. Spraying disinfectant in the shed and removing feces were the only regular cleaning and disinfection activities observed. All farmers sold or used untreated feces as fish feed or fertilizer. Farmers were more concerned about Newcastle disease and infectious bursal disease than about avian influenza. Farmers' understanding about biosecurity and avian influenza was influenced by local vendors. While we seldom observed flock segregation, some farmers used measures that involved additional cost or effort to protect their flocks. These farmers could be motivated by interventions to protect their investment from diseases they consider harmful. Future interventions could explore the feasibility and effectiveness of low-cost alternative biosecurity measures.

77 FR 62248 - Commercial Fishing Safety Advisory Committee; Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-12

... DEPARTMENT OF HOMELAND SECURITY Coast Guard [Docket No. USCG-2012-0936] Commercial Fishing Safety.... SUMMARY: The Commercial Fishing Safety Advisory Committee (CFSAC) will meet in Washington, DC to discuss various issues relating to safety in the commercial fishing industry. This meeting will be open to the...

76 FR 65205 - Commercial Fishing Safety Advisory Committee; Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-20

... DEPARTMENT OF HOMELAND SECURITY Coast Guard [Docket No. USCG-2011-0979] Commercial Fishing Safety.... SUMMARY: The Commercial Fishing Safety Advisory Committee (CFSAC) will meet in Seattle, Washington to discuss various issues relating to safety in the commercial fishing industry. This meeting will be open to...

76 FR 8372 - Commercial Fishing Safety Advisory Committee; Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-14

... DEPARTMENT OF HOMELAND SECURITY Coast Guard [Docket No. USCG-2011-0070] Commercial Fishing Safety... Commercial Fishing Safety Advisory Committee (CFSAC) will meet in Portsmouth, Virginia to discuss various issues relating to safety in the commercial fishing industry. This meeting will be open to the public...

Effects of temperature and diet on length-weight relationship and condition factor of the juvenile Malabar blood snapper (Lutjanus malabaricus Bloch & Schneider, 1801).

PubMed

Mazumder, Sabuj Kanti; Das, Simon Kumar; Bakar, Yosni; Ghaffar, Mazlan Abd

2016-08-01

In this study we aimed to analyze the effects of water temperature and diet on the length-weight relationship and condition of juvenile Malabar blood snapper Lutjanus malabaricus over a 30-d experimental period. The experiment was conducted in the laboratory using a flow-through-sea-water system. The fish were subjected to four different temperatures (22, 26, 30, and 34 °C) and two diets (commercial pellet and natural shrimp). Fish were fed twice daily. L. malabaricus exhibited negative allometric growth (b<3) at the beginning of the experiment (Day 0) at all temperatures and both diets except for 22 °C fed with shrimp, which showed isometric growth (b=3). Conversely, at the end of the experiment (Day 30) fish showed isometric growth (b=3) at 30 °C fed with the pellet diet, indicating that the shape of the fish did not change with increasing weight and length, and a positive allometric growth (b>3) at 30 °C fed with shrimp diet, which indicated that fish weight increases faster than their length. The rest of the temperatures represented negative allometric growth (b<3) on both diet, meaning that fish became lighter with increasing size. The condition factors in the initial and final measurements were greater than 1, indicating the state of health of the fish, except for those fed on a pellet diet at 34 °C. However, the best condition was obtained at 30 °C on both diets. Nevertheless, diets did not have a significant effect on growth and condition of juvenile L. malabaricus. The data obtained from this study suggested culturing L. malabaricus at 30 °C and feeding on the pellet or shrimp diet, which will optimize the overall production and condition of this commercially important fish species.

Dining in the Deep: The Feeding Ecology of Deep-Sea Fishes

NASA Astrophysics Data System (ADS)

Drazen, Jeffrey C.; Sutton, Tracey T.

2017-01-01

Deep-sea fishes inhabit ˜75% of the biosphere and are a critical part of deep-sea food webs. Diet analysis and more recent trophic biomarker approaches, such as stable isotopes and fatty-acid profiles, have enabled the description of feeding guilds and an increased recognition of the vertical connectivity in food webs in a whole-water-column sense, including benthic-pelagic coupling. Ecosystem modeling requires data on feeding rates; the available estimates indicate that deep-sea fishes have lower per-individual feeding rates than coastal and epipelagic fishes, but the overall predation impact may be high. A limited number of studies have measured the vertical flux of carbon by mesopelagic fishes, which appears to be substantial. Anthropogenic activities are altering deep-sea ecosystems and their services, which are mediated by trophic interactions. We also summarize outstanding data gaps.

Deposition and mobilization of lipids varies across the rainbow trout fillet during feed deprivation and transition from plant to fish oil-based diets

USDA-ARS?s Scientific Manuscript database

Identifying aquaculture feeding strategies that reduce the consumption of fish oil without sacrificing the cardioprotective lipid profile of the salmonid fillet will improve aquafeed economics and sustainability. Transitioning fish from a plant oil-based diet to a finishing diet rich in fish oil an...

75 FR 20372 - Commercial Fishing Industry Vessel Safety Advisory Committee; Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-19

... DEPARTMENT OF HOMELAND SECURITY Coast Guard [USCG-2010-0276] Commercial Fishing Industry Vessel... Commercial Fishing Industry Vessel Safety Advisory Committee (CFIVSAC) will meet in Oakland, CA, to discuss various issues relating to commercial vessel safety in the fishing industry. This meeting will be open to...

46 CFR 105.05-1 - Commercial fishing vessels dispensing petroleum products.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Commercial fishing vessels dispensing petroleum products... MISCELLANEOUS VESSELS COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Application § 105.05-1 Commercial fishing vessels dispensing petroleum products. (a) The provisions of this part, with the exception of...

46 CFR 105.05-1 - Commercial fishing vessels dispensing petroleum products.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Commercial fishing vessels dispensing petroleum products... MISCELLANEOUS VESSELS COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Application § 105.05-1 Commercial fishing vessels dispensing petroleum products. (a) The provisions of this part, with the exception of...

46 CFR 105.05-1 - Commercial fishing vessels dispensing petroleum products.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Commercial fishing vessels dispensing petroleum products... MISCELLANEOUS VESSELS COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Application § 105.05-1 Commercial fishing vessels dispensing petroleum products. (a) The provisions of this part, with the exception of...

76 FR 67121 - Atlantic Highly Migratory Species; 2012 Atlantic Shark Commercial Fishing Season

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-31

.... 110913585-1625-01] RIN 0648-BB36 Atlantic Highly Migratory Species; 2012 Atlantic Shark Commercial Fishing... establish opening dates and adjust quotas for the 2012 fishing season for the Atlantic commercial shark... 2011 Atlantic commercial shark fishing seasons. In addition, NMFS proposes season openings based on...

Mercury bioaccumulation in offshore reef fishes from waters of the Southeastern USA.

PubMed

Sinkus, Wiley; Shervette, Virginia; Ballenger, Joseph; Reed, Lou Ann; Plante, Craig; White, Byron

2017-09-01

Mercury (Hg) concentrations and nitrogen (δ 15 N) and carbon (δ 13 C) stable isotopic ratios were measured to assess differences in Hg bioaccumulation in four predatory fish species (Mycteroperca microlepis, Lutjanus campechanus, Caulolatilus microps, and Serioli dumerili) of high commercial and recreational importance in Atlantic waters of the southeastern US. Positive relationships existed between Hg and length, weight, and age, for all species, strongest for M. microlepis and L. campechanus. Intraspecific Hg concentrations also strongly correlated with δ 15 N for all species, and δ 13 C for only L. campechanus, and S. dumerili. Comparisons of stable isotopes between species and their impact on mean Hg concentration were inconclusive. This study is the first to report Hg concentrations for C. microps. The current study provides data for an under-sampled region, explores how feeding ecology impacts Hg uptake in commonly co-occurring fishes, and raises questions of the importance of sex and reproduction in Hg accumulation for marine fishes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluation of nutritive quality of common carp, Cyprinus carpio L.

NASA Astrophysics Data System (ADS)

Ljubojević, D.; Đorđević, V.; Ćirković, M.

2017-09-01

Common carp is the most important commercial fish species in Serbia. This fish is a valuable source of nutritive components and plays a role in healthy human nutrition. This review evaluates the nutritive quality of common carp including proximate and fatty acid compositions as well as their effects on human health. The fat content and fatty acid composition of carp have been shown to vary due to different environmental factors and particularly due to nutrition. Technology of production and composition of planktonic and benthic organisms in fish ponds have been recognised as significant factors affecting carp meat quality and desirable chemical and fatty acid composition. Carp meat quality but also production parameters and fish health are positively influenced by a balanced feed mixture. Due to the low content of saturated fatty acids and cholesterol plus high levels of unsaturated fatty acids, common carp meat consumption could be linked with reduced risk of different heart diseases in humans. Also, fish proteins can have many beneficial roles in the preservation of human health. This paper emphasises the importance of consumption of common carp in order to prevent many diseases and preserve human health.

Three-year breeding cycle of rainbow trout (Oncorhynchus mykiss) fed a plant-based diet, totally free of marine resources: consequences for reproduction, fatty acid composition and progeny survival.

PubMed

Lazzarotto, Viviana; Corraze, Geneviève; Leprevost, Amandine; Quillet, Edwige; Dupont-Nivet, Mathilde; Médale, Françoise

2015-01-01

Terrestrial plant resources are increasingly used as substitutes for fish meal and fish oil in fish feed in order to reduce the reliance of aquaculture on marine fishery resources. Although many studies have been conducted to assess the effects of such nutritional transition, no whole breeding cycles of fish fed diets free from marine resources has been reported to date. We therefore studied the reproductive performance of trout after a complete cycle of breeding while consuming a diet totally devoid of marine ingredients and thus of n-3 long chain polyunsaturated fatty acids (n-3 LC-PUFAs) that play a major role in the formation of ova. Two groups of female rainbow trout were fed from first feeding either a commercial diet (C, marine and plant ingredients), or a 100% plant-based diet (V, blend of plant proteins and vegetable oils). Livers, viscera, carcasses and ova were sampled at spawning and analyzed for lipids and fatty acids. Although the V-diet was devoid of n-3 LC-PUFAs, significant amounts of EPA and DHA were found in livers and ova, demonstrating efficient bioconversion of linolenic acid and selective orientation towards the ova. Some ova were fertilized to assess the reproductive performance and offspring survival. We observed for the first time that trout fed a 100% plant-based diet over a 3-year breeding cycle were able to produce ova and viable alevins, although the ova were smaller. The survival of offspring from V-fed females was lower (-22%) at first spawning, but not at the second. Our study showed that, in addition to being able to grow on a plant-based diet, rainbow trout reared entirely on such a diet can successfully produce ova in which neo-synthesized n-3 LC-PUFAs are accumulated, leading to viable offspring. However, further adjustment of the feed formula is still needed to optimize reproductive performance.

Three-Year Breeding Cycle of Rainbow Trout (Oncorhynchus mykiss) Fed a Plant-Based Diet, Totally Free of Marine Resources: Consequences for Reproduction, Fatty Acid Composition and Progeny Survival

PubMed Central

Lazzarotto, Viviana; Corraze, Geneviève; Leprevost, Amandine; Quillet, Edwige; Dupont-Nivet, Mathilde; Médale, Françoise

2015-01-01

Terrestrial plant resources are increasingly used as substitutes for fish meal and fish oil in fish feed in order to reduce the reliance of aquaculture on marine fishery resources. Although many studies have been conducted to assess the effects of such nutritional transition, no whole breeding cycles of fish fed diets free from marine resources has been reported to date. We therefore studied the reproductive performance of trout after a complete cycle of breeding while consuming a diet totally devoid of marine ingredients and thus of n-3 long chain polyunsaturated fatty acids (n-3 LC-PUFAs) that play a major role in the formation of ova. Two groups of female rainbow trout were fed from first feeding either a commercial diet (C, marine and plant ingredients), or a 100% plant-based diet (V, blend of plant proteins and vegetable oils). Livers, viscera, carcasses and ova were sampled at spawning and analyzed for lipids and fatty acids. Although the V-diet was devoid of n-3 LC-PUFAs, significant amounts of EPA and DHA were found in livers and ova, demonstrating efficient bioconversion of linolenic acid and selective orientation towards the ova. Some ova were fertilized to assess the reproductive performance and offspring survival. We observed for the first time that trout fed a 100% plant-based diet over a 3-year breeding cycle were able to produce ova and viable alevins, although the ova were smaller. The survival of offspring from V-fed females was lower (-22%) at first spawning, but not at the second. Our study showed that, in addition to being able to grow on a plant-based diet, rainbow trout reared entirely on such a diet can successfully produce ova in which neo-synthesized n-3 LC-PUFAs are accumulated, leading to viable offspring. However, further adjustment of the feed formula is still needed to optimize reproductive performance. PMID:25658483

Genetic Relatedness of Salmonella Serovars Isolated from Catfish (Clarias gariepinus) and Tilapia (Tilapia mossambica) Obtained from Wet Markets and Ponds in Penang, Malaysia.

PubMed

Budiati, Titik; Rusul, Gulam; Wan-Abdullah, Wan Nadiah; Chuah, Li-Oon; Ahmad, Rosma; Thong, Kwai Lin

2016-04-01

A total of 43 Salmonella enterica isolates belonging to different serovars (Salmonella Albany, Salmonella Agona, Salmonella Corvallis, Salmonella Stanley, Salmonella Typhimurium, Salmonella Mikawasima, and Salmonella Bovismorbificans) were isolated from catfish (Clarias gariepinus) and tilapia (Tilapia mossambica) obtained from nine wet markets and eight ponds in Penang, Malaysia. Thirteen, 19, and 11 isolates were isolated from 9 of 32 catfish, 14 of 32 tilapia, and 11 of 44 water samples, respectively. Fish reared in ponds were fed chicken offal, spoiled eggs, and commercial fish feed. The genetic relatedness of these Salmonella isolates was determined by random amplified polymorphic DNA PCR (RAPD-PCR) using primer OPC2, repetitive extragenic palindromic PCR (REP-PCR), and pulsed-field gel electrophoresis (PFGE). Composite analysis of the RAPD-PCR, REP-PCR, and PFGE results showed that the Salmonella serovars could be differentiated into six clusters and 15 singletons. RAPD-PCR differentiated the Salmonella isolates into 11 clusters and 10 singletons, while REP-PCR differentiated them into 4 clusters and 1 singleton. PFGE differentiated the Salmonella isolates into seven clusters and seven singletons. The close genetic relationship of Salmonella isolates from catfish or tilapia obtained from different ponds, irrespective of the type of feed given, may be caused by several factors, such as the quality of the water, density of fish, and size of ponds.

46 CFR 25.26-5 - Commercial fishing industry vessels.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 1 2013-10-01 2013-10-01 false Commercial fishing industry vessels. 25.26-5 Section 25... Position Indicating Radio Beacons (EPIRB) § 25.26-5 Commercial fishing industry vessels. (a) The owner of a fishing vessel, a fish processing vessel, or a fish tender vessel, 11 meters (36 feet) or more in length...

46 CFR 25.26-5 - Commercial fishing industry vessels.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 1 2014-10-01 2014-10-01 false Commercial fishing industry vessels. 25.26-5 Section 25... Position Indicating Radio Beacons (EPIRB) § 25.26-5 Commercial fishing industry vessels. (a) The owner of a fishing vessel, a fish processing vessel, or a fish tender vessel, 11 meters (36 feet) or more in length...

46 CFR 25.26-5 - Commercial fishing industry vessels.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 1 2011-10-01 2011-10-01 false Commercial fishing industry vessels. 25.26-5 Section 25... Position Indicating Radio Beacons (EPIRB) § 25.26-5 Commercial fishing industry vessels. (a) The owner of a fishing vessel, a fish processing vessel, or a fish tender vessel, 11 meters (36 feet) or more in length...

46 CFR 25.26-5 - Commercial fishing industry vessels.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Commercial fishing industry vessels. 25.26-5 Section 25... Position Indicating Radio Beacons (EPIRB) § 25.26-5 Commercial fishing industry vessels. (a) The owner of a fishing vessel, a fish processing vessel, or a fish tender vessel, 11 meters (36 feet) or more in length...

46 CFR 25.26-5 - Commercial fishing industry vessels.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 1 2012-10-01 2012-10-01 false Commercial fishing industry vessels. 25.26-5 Section 25... Position Indicating Radio Beacons (EPIRB) § 25.26-5 Commercial fishing industry vessels. (a) The owner of a fishing vessel, a fish processing vessel, or a fish tender vessel, 11 meters (36 feet) or more in length...

Effect of feeding silkworm on growth performance and feed efficiency of snakehead (Channa striata)

NASA Astrophysics Data System (ADS)

Firmani, U.; Lono

2018-04-01

The snakehead, Chana striata is a carnivorous freshwater fish and widely distributed in Asia. High demand of this fish has been triggering many aquaculturist to culture C. stiata. Feed was the important factor for fish growth. Silkworm has high protein content, low fat and can be used as natural feed for finfish. This study investigate the silkworm feed in C. striata. The treatment of this research were A (100 % pellet); B (100 % silkworm); C (combination of 75 % pellet and 25 % silkworm); D (combination of 50 % pellet and 50 % silkworm); and E (combination of 25 % pellet and 75 % silkworm). The variables measured in this study were relatif growth, specific growth rate, feed efficiency, feed conversion ratio, and survival rate. The result show that silkworm gave the high growth performance, feed efficiency and survival rate of the snakehead (Channa striata) compared with the control.

Microbiome dynamic modulation through functional diets based on pre- and probiotics (mannan-oligosaccharides and Saccharomyces cerevisiae) in juvenile rainbow trout (Oncorhynchus mykiss).

PubMed

Gonçalves, A T; Gallardo-Escárate, C

2017-05-01

This study used high-throughput sequencing to evaluate the intestinal microbiome dynamics in rainbow trout (Oncorhynchus mykiss) fed commercial diets supplemented with either pre- or probiotics (0·6% mannan-oligosaccharides and 0·5% Saccharomyces cerevisiae respectively) or the mixture of both. A total of 57 fish whole intestinal mucosa and contents bacterial communities were characterized by high-throughput sequencing and analysis of the V3-V4 region of the 16S rRNA gene, as well as the relationship between plasma biochemical health indicators and microbiome diversity. This was performed at 7, 14 and 30 days after start feeding functional diets, and microbiome diversity increased when fish fed functional diets after 7 days and it was positively correlated with plasma cholesterol levels. Dominant phyla were, in descending order, Proteobacteria, Firmicutes, Actinobacteria, Acidobacteria, Bacteroidetes and Fusobacteria. However, functional diets reduced the abundance of Gammaproteobacteria to favour abundances of organisms from Firmicutes and Fusobacteria, two phyla with members that confer beneficial effects. A dynamic shift of the microbiome composition was observed with changes after 7 days of feeding and the modulation by functional diets tend to cluster the corresponding groups apart from CTRL group. The core microbiome showed an overall stability with functional diets, except genus such as Escherichia-Shigella that suffered severe reductions on their abundances when feeding any of the functional diets. Functional diets based on pre- or probiotics dynamically modulate intestinal microbiota of juvenile trout engaging taxonomical abundance shifts that might impact fish physiological performance. This study shows for the first time the microbiome modulation dynamics by functional diets based on mannan-oligosaccharides and S. cerevisiae and their synergy using culture independent high-throughput sequencing technology, revealing the complexity behind the dietary modulation with functional feeds in aquatic organisms. © 2017 The Society for Applied Microbiology.

How can plant genetic engineering contribute to cost-effective fish vaccine development for promoting sustainable aquaculture?

PubMed

Clarke, Jihong Liu; Waheed, Mohammad Tahir; Lössl, Andreas G; Martinussen, Inger; Daniell, Henry

2013-09-01

Aquaculture, the fastest growing food-producing sector, now accounts for nearly 50 % of the world's food fish (FAO in The state of world fisheries and aquaculture. FAO, Rome, 2010). The global aquaculture production of food fish reached 62.7 million tonnes in 2011 and is continuously increasing with an estimated production of food fish of 66.5 million tonnes in 2012 (a 9.4 % increase in 1 year, FAO, www.fao.org/fishery/topic/16140 ). Aquaculture is not only important for sustainable protein-based food fish production but also for the aquaculture industry and economy worldwide. Disease prevention is the key issue to maintain a sustainable development of aquaculture. Widespread use of antibiotics in aquaculture has led to the development of antibiotic-resistant bacteria and the accumulation of antibiotics in the environment, resulting in water and soil pollution. Thus, vaccination is the most effective and environmentally-friendly approach to combat diseases in aquaculture to manage fish health. Furthermore, when compared to >760 vaccines against human diseases, there are only about 30 fish vaccines commercially available, suggesting the urgent need for development and cost-effective production of fish vaccines for managing fish health, especially in the fast growing fish farming in Asia where profit is minimal and therefore given high priority. Plant genetic engineering has made significant contributions to production of biotech crops for food, feed, valuable recombinant proteins etc. in the past three decades. The use of plants for vaccine production offers several advantages such as low cost, safety and easy scaling up. To date a large number of plant-derived vaccines, antibodies and therapeutic proteins have been produced for human health, of which a few have been made commercially available. However, the development of animal vaccines in plants, especially fish vaccines by genetic engineering, has not yet been addressed. Therefore, there is a need to exploit plant biotechnology for cost effective fish vaccine development in plants, in particular, edible crops for oral fish vaccines. This review provides insight into (1) the current status of fish vaccine and vaccination in aquaculture, (2) plant biotechnology and edible crops for fish vaccines for oral administration, (3) regulatory constraints and (4) conclusions and future perspectives.

[Effects of fish on field resource utilization and rice growth in rice-fish coculture].

PubMed

Zhang, Jian; Hu, Liang Liang; Ren, Wei Zheng; Guo, Liang; Wu, Min Fang; Tang, Jian Jun; Chen, Xin

2017-01-01

Rice field can provide habitat for fish and other aquatic animals. Rice-fish coculture can increase rice yield and simultaneously reduce the use of chemicals through reducing rice pest occurrence and nutrient complementary use. However, how fish uses food sources (e.g. phytoplankton, weeds, duckweed, macro-algal and snail) from rice field, and whether the nutrients releasing from those food sources due to fish transforming can improve rice growth are still unknown. Here, we conducted two field experiments to address these questions. One was to investigate the pattern of fish activity in the field using the method of video recording. The other was to examine the utilization of field resources by fish using stable isotope technology. Rice growth and rice yield were also exa-mined. Results showed that fish tended to be more active and significantly expanded the activity range in the rice-fish coculture compared to fish monoculture (fish not living together with rice plants). The contributions of 3 potential aquatic organisms (duckweed, phytoplankton and snail) to fish dietary were 22.7%, 34.8% and 30.0% respectively under rice-fish coculture without feed. Under the treatment with feed, however, the contributions of these 3 aquatic organisms to the fish die-tary were 8.9%, 5.9% and 1.6% respectively. The feed contribution was 71.0%. Rice-fish coculture significantly increased the nitrogen concentration in rice leaves, prolonged tillering stage by 10-12 days and increased rice spike rate and yield. The results suggested that raising fish in paddy field may transform the nutrients contained in field resources to bioavailable for rice plants through fish feeding activity, which can improve rice growth and rice yield.

Towards Sustainable Aquafeeds: Complete Substitution of Fish Oil with Marine Microalga Schizochytrium sp. Improves Growth and Fatty Acid Deposition in Juvenile Nile Tilapia (Oreochromis niloticus)

PubMed Central

Sarker, Pallab K.; Kapuscinski, Anne R.; Lanois, Alison J.; Livesey, Erin D.; Bernhard, Katie P.; Coley, Mariah L.

2016-01-01

We conducted a 84-day nutritional feeding experiment with dried whole cells of DHA-rich marine microalga Schizochytrium sp. (Sc) to determine the optimum level of fish-oil substitution (partial or complete) for maximum growth of Nile tilapia. When we fully replaced fish oil with Schizochytrium (Sc100 diet), we found significantly higher weight gain and protein efficiency ratio (PER), and lower (improved) feed conversion ratio (FCR) and feed intake compared to a control diet containing fish oil (Sc0); and no significant change in SGR and survival rate among all diets. The Sc100 diet had the highest contents of 22:6n3 DHA, led to the highest DHA content in fillets, and consequently led to the highest DHA:EPA ratios in tilapia fillets. Schizochytrium sp. is a high quality candidate for complete substitution of fish oil in juvenile Nile tilapia feeds, providing an innovative means to formulate and optimize the composition of tilapia juvenile feed while simultaneously raising feed efficiency of tilapia aquaculture and to further develop environmentally and socially sustainable aquafeeds. Results show that replacing fish oil with DHA-rich marine Sc improves the deposition of n3 LC PUFA levels in tilapia fillet. These results support further studies to lower Schizochytrium production costs and to combine different marine microalgae to replace fish oil and fishmeal into aquafeeds. PMID:27258552

25 CFR 241.5 - Commercial fishing, Karluk Indian Reservation.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 25 Indians 1 2011-04-01 2011-04-01 false Commercial fishing, Karluk Indian Reservation. 241.5 Section 241.5 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE INDIAN FISHING IN ALASKA § 241.5 Commercial fishing, Karluk Indian Reservation. (a) Definition. The Karluk Indian...

25 CFR 241.5 - Commercial fishing, Karluk Indian Reservation.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 25 Indians 1 2012-04-01 2011-04-01 true Commercial fishing, Karluk Indian Reservation. 241.5 Section 241.5 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE INDIAN FISHING IN ALASKA § 241.5 Commercial fishing, Karluk Indian Reservation. (a) Definition. The Karluk Indian...

25 CFR 241.5 - Commercial fishing, Karluk Indian Reservation.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Commercial fishing, Karluk Indian Reservation. 241.5 Section 241.5 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE INDIAN FISHING IN ALASKA § 241.5 Commercial fishing, Karluk Indian Reservation. (a) Definition. The Karluk Indian...

25 CFR 241.5 - Commercial fishing, Karluk Indian Reservation.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 25 Indians 1 2013-04-01 2013-04-01 false Commercial fishing, Karluk Indian Reservation. 241.5 Section 241.5 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE INDIAN FISHING IN ALASKA § 241.5 Commercial fishing, Karluk Indian Reservation. (a) Definition. The Karluk Indian...

Pesticide-contaminated feeds in integrated grass carp aquaculture: toxicology and bioaccumulation.

PubMed

Pucher, J; Gut, T; Mayrhofer, R; El-Matbouli, M; Viet, P H; Ngoc, N T; Lamers, M; Streck, T; Focken, U

2014-02-19

Effects of dissolved pesticides on fish are widely described, but little is known about effects of pesticide-contaminated feeds taken up orally by fish. In integrated farms, pesticides used on crops may affect grass carp that feed on plants from these fields. In northern Vietnam, grass carp suffer seasonal mass mortalities which may be caused by pesticide-contaminated plants. To test effects of pesticide-contaminated feeds on health and bioaccumulation in grass carp, a net-cage trial was conducted with 5 differently contaminated grasses. Grass was spiked with 2 levels of trichlorfon/fenitrothion and fenobucarb. Unspiked grass was used as a control. Fish were fed at a daily rate of 20% of body mass for 10 d. The concentrations of fenitrothion and fenobucarb in pond water increased over time. Effects on fish mortality were not found. Fenobucarb in feed showed the strongest effects on fish by lowering feed uptake, deforming the liver, increasing blood glucose and reducing cholinesterase activity in blood serum, depending on feed uptake. Fenobucarb showed increased levels in flesh in all treatments, suggesting bio-concentration. Trichlorfon and fenitrothion did not significantly affect feed uptake but showed concentration-dependent reduction of cholinesterase activity and liver changes. Fenitrothion showed bioaccumulation in flesh which was dependant on feed uptake, whereas trichlorfon was only detected in very low concentrations in all treatments. Pesticide levels were all detected below the maximum residue levels in food. The pesticide-contaminated feeds tested did not cause mortality in grass carp but were associated with negative physiological responses and may increase susceptibility to diseases.

Bioenergetics modeling of the annual consumption of zooplankton by pelagic fish feeding in the Northeast Atlantic

PubMed Central

Utne, Kjell Rong; Jansen, Teunis; Huse, Geir

2018-01-01

The present study uses bioenergetics modeling to estimate the annual consumption of the main zooplankton groups by some of the most commercially important planktivorous fish stocks in the Northeast Atlantic, namely Norwegian spring-spawning (NSS) herring (Clupea harengus), blue whiting (Micromesistius poutassou) and NEA mackerel (Scomber scombrus). The data was obtained from scientific surveys in the main feeding area (Norwegian Sea) in the period 2005–2010. By incorporating novel information about ambient temperature, seasonal growth and changes in the diet from stomach content analyses, annual consumption of the different zooplankton groups by pelagic fish is estimated. The present study estimates higher consumption estimates than previous studies for the three species and suggests that fish might have a greater impact on the zooplankton community as foragers. This way, NEA mackerel, showing the highest daily consumption rates, and NSS herring, annually consume around 10 times their total biomass, whereas blue whiting consume about 6 times their biomass in zooplankton. The three species were estimated to consume an average of 135 million (M) tonnes of zooplankton each year, consisting of 53–85 M tonnes of copepods, 20–32 M tonnes of krill, 8–42 M tonnes of appendicularians and 0.2–1.2 M tonnes of fish, depending on the year. For NSS herring and NEA mackerel the main prey groups are calanoids and appendicularians, showing a peak in consumption during June and June–July, respectively, and suggesting high potential for inter-specific feeding competition between these species. In contrast, blue whiting maintain a low consumption rate from April to September, consuming mainly larger euphausiids. Our results suggest that the three species can coexist regardless of their high abundance, zooplankton consumption rates and overlapping diet. Accordingly, the species might have niche segregation, as they are species specific, showing annual and inter-annual variability in total consumption of the different prey species. These estimates and their inter-annual and inter-specific variation are fundamental for understanding fundamental pelagic predator-prey interactions as well as to inform advanced multispecies ecosystem models. PMID:29293577

Dietary supplementation of Pediococcus pentosaceus enhances innate immunity, physiological health and resistance to Vibrio anguillarum in orange-spotted grouper (Epinephelus coioides).

PubMed

Huang, Jian-Bin; Wu, Yu-Chi; Chi, Shau-Chi

2014-08-01

Groupers (Epinephelus spp.) are economically important fish species in Southeast Asian aquaculture. Vibriosis caused by Vibro spp. is one of the severe bacterial diseases that devastate the grouper aquaculture industry. Probiotics have been reported to show the potential to enhance fish immunity and to antagonize pathogens. In our previous study, a lactic acid bacterium Pediococcus pentosaceus strain 4012 (LAB4012), isolated from cobia intestine, protects cobia from photobacteriosis after a 2-week feeding. In this study, we examined the potential of LAB4012 to be a probiotic for the orange-spotted grouper through feeding, thus to guard against vibriosis. In vitro, LAB4012 culture supernatant with low pH suppressed the growth of Vibrio anguillarum, and lactic acid in the metabolite of LAB4012 appeared to be the major factor to the growth inhibition of V. anguillarum. In vivo, the challenge test showed that the cumulative mortality of the LAB4012-fed groupers was significantly lower than that of the control fish after V. anguillarum infection. Supplementation of LAB4012 in commercial diet not only enhanced the growth rate and erythrocyte numbers of the groupers, but also regulated the gene expression of the pro-/anti-inflammatory cytokines. One day post-infection of V. anguillarum, the leukocyte numbers in the peripheral blood and the phagocytic activity of the head-kidney phagocytes in the LAB4012-fed groupers were found significantly increased, when compared with those without LAB4012-feeding. These results suggested that LAB4012 can be a dietary probiotic for groupers in modulating the immunity and protecting the groupers from V. anguillarum infection. Copyright © 2014 Elsevier Ltd. All rights reserved.

β-1,3 glucan derived from Euglena gracilis and Algamune™ enhances innate immune responses of red drum (Sciaenops ocellatus L.).

PubMed

Yamamoto, Fernando Y; Yin, Fei; Rossi, Waldemar; Hume, Michael; Gatlin, Delbert M

2018-06-01

To reduce susceptibility to stressors and diseases, immune-modulators such as β-glucans have been proven effective tools to enhance the innate immune responses of fish. Consequently, commercial sources of this polysaccharide are becoming increasingly more available. Algamune™ is a commercial additive produced from Euglena gracilis, as a source of linear β-1,3-glucan. In order to evaluate the immunomodulatory effects of this β-glucan product, the present study assessed the innate immune parameters of red drum (Sciaenops ocellatus) exposed to Algamune™ ex vivo and in vivo. Isolated kidney phagocytes were incubated with graded concentrations (0, 0.2, 0.4, 0.8, 1.6 and 3.2 mg L -1 ) of dried Euglena gracilis (Algamune™) as well as purified Paramylon (linear β-1,3 glucan). Increased bactericidal activity against Streptococcus iniae, and production of intracellular O 2 - anion superoxide were stimulated by both β-glucan sources. A reduced activity of extracellular anion superoxide was observed by the phagocytes incubated with Algamune ™. After corroborating the effectiveness of the glucan source ex vivo, a feeding trial was conducted using red drum juveniles (∼26.6 g initial weight). Fish were fed diets with graded levels of Algamune™ (0, 100, 200, 400 and 800 mg kg -1 ) twice daily for 21 days. No significant differences were detected regarding production performance parameters. At the end of the feeding trial, blood, intestinal content, and kidney were sampled. Intestinal microbiota from fecal material was analyzed through denaturing gradient gel electrophoresis (DGGE) and found to be similar among all treatments. No significant differences were detected for oxidative radical production from whole blood, and isolated phagocytes, and plasma lysozyme activity. However, the total hemolytic activity of red drum plasma was increased in fish fed 100 and 200 mg kg -1 of dietary Algamune™ when compared to fish fed the basal diet. Based on results from both ex vivo and in vivo trials, β-glucan from Algamune™ was demonstrated to have a moderate immunostimulatory effects on red drum. Copyright © 2018 Elsevier Ltd. All rights reserved.

Stable Isotope Signatures Suggest Different Feeding Strategies for Atlantic and Gulf Menhaden

NASA Astrophysics Data System (ADS)

Perez-Perez, N.; Smith, S. L.; Gonsalves, L. C.; Lamb, M.

2016-02-01

Atlantic menhaden (Brevoortia tyrannus) is a keystone forage species that ranges on the Atlantic Coast from Nova Scotia to Florida. A related species, the Gulf menhaden (Brevoortia patronus) is found in the northern Gulf of Mexico from Florida to Texas. They each serve as prey for important recreational and commercial fish, such as blue fish, tuna and striped bass. Menhaden are filter feeders whose diets consist mostly of phytoplankton and zooplankton, and menhaden act as direct links between primary producers and larger valuable predators. In this study, we investigated and compared the isotopic signatures of water column nitrate (δ15N), bulk plankton and juvenile menhaden (δ 15N and δ 13C) collected from 5 sites in both the Choptank River, MD, and Apalachicola Bay, FL. We determined that menhaden inhabiting the temperate zone versus the sub-tropical region exhibited statistically different isotopic signatures, suggesting different feeding strategies. Choptank River menhaden were enriched 4‰ in δ 15N over Apalachicola Bay menhaden. Choptank River menhaden are mostly likely obtaining their diet from a higher trophic level (copepods, primary consumers) than Apalachicola Bay fish, who may consume more phytoplankton. The Choptank River menhaden also may be consuming more allochthonous material, and those from the Gulf area eat a more authochthonous diet. In addition, Atlantic menhaden collected from fresh water creeks versus those collected closer to the bay differed in their δ 13C compositions, depending on site collection, with creek fish being more depleted in the heavier carbon isotope. The δ 15N values of water column nitrate were similar at Choptank and Apalachicola sites.

Trophic characteristics of a mangrove fish community in Southwest Thailand: Important mangrove contribution and intraspecies feeding variability

NASA Astrophysics Data System (ADS)

Zagars, Matiss; Ikejima, Kou; Kasai, Akihide; Arai, Nobuaki; Tongnunui, Prasert

2013-03-01

Mangrove production has been found to make a major contribution to the nutrition of a fish community in the Sikao Creek mangrove estuary, Southwest Thailand. Gut content analysis and carbon and nitrogen stable isotope analysis were used to assess fish feeding behavior and trophic reliance on different primary producers (mangrove leaves, phytoplankton, microphytobenthos) focusing on 19 dominant fish species, and 4 potential fish food items. Cluster analysis identified 5 trophic groups and the IsoSource model indicated the importance of primary food sources in trophically supporting different fish species. Most analyzed fish species had carbon isotopic signatures that were more depleted than those reported in previous studies, and the IsoSource model indicated that mangrove leaves were an important primary food source. This may be a specific characteristic of our study site, which is not well connected to other productive coastal habitats that provide alternative primary food sources. Thus we suggest that food chains in trophically isolated mangrove estuaries of southwest Thailand are more dependent on mangrove tree production. We also assessed the relationship of individuality in fish feeding habits and variability of δ13C values and showed that several mangrove fish species have significant intraspecies variability in feeding habits, possibly due to high intraspecific competition.

Comparison of biochemical parameters of rainbow trout (Oncorhynchus mykiss) reared in two different trout farms'

NASA Astrophysics Data System (ADS)

Karatas, Tayfun

2016-04-01

The aim of this study was to compare biochemical parameters of cultured rainbow trouts (Oncorhynchus mykiss, Walbaum, 1972) reared in two different trout farms' (Agri and Erzurum). The average weights of fish were 150±10gr for first station (Agri), 230±10gr for second station (Erzurum). Fishes used in research were randomly caught from pools, and fifteen pieces were used for each group. Fishes were fed with commercial trout feed with 45-50% crude protein twice a day. The levels of AST, ALT, LDL, total cholesterol and triglyceride in the second station (Erzurum) were found to be higher (p<0.05) than that of first station (Agri). Whereas, the levels of HDL in the second station (Erzurum) were found to be lower (p<0.05) than that of first station (Agri). Differences in the levels of total cholesterol and AST, ALT, HDL, LDL, triglyceride may be associated with size, sex, sexual maturity and environmental conditions (temperature, pH, hardness and dissolved oxygen).

33 CFR 1.07-100 - Summons in lieu of seizure of commercial fishing industry vessels.

Code of Federal Regulations, 2014 CFR

2014-07-01

... commercial fishing industry vessels. 1.07-100 Section 1.07-100 Navigation and Navigable Waters COAST GUARD... Proceedings § 1.07-100 Summons in lieu of seizure of commercial fishing industry vessels. (a) As used in this section, the following terms have the meanings specified: (1) Commercial fishing industry vessel means a...

33 CFR 1.07-100 - Summons in lieu of seizure of commercial fishing industry vessels.

Code of Federal Regulations, 2012 CFR

2012-07-01

... commercial fishing industry vessels. 1.07-100 Section 1.07-100 Navigation and Navigable Waters COAST GUARD... Proceedings § 1.07-100 Summons in lieu of seizure of commercial fishing industry vessels. (a) As used in this section, the following terms have the meanings specified: (1) Commercial fishing industry vessel means a...

33 CFR 1.07-100 - Summons in lieu of seizure of commercial fishing industry vessels.

Code of Federal Regulations, 2011 CFR

2011-07-01

... commercial fishing industry vessels. 1.07-100 Section 1.07-100 Navigation and Navigable Waters COAST GUARD... Proceedings § 1.07-100 Summons in lieu of seizure of commercial fishing industry vessels. (a) As used in this section, the following terms have the meanings specified: (1) Commercial fishing industry vessel means a...

33 CFR 1.07-100 - Summons in lieu of seizure of commercial fishing industry vessels.

Code of Federal Regulations, 2013 CFR

2013-07-01

... commercial fishing industry vessels. 1.07-100 Section 1.07-100 Navigation and Navigable Waters COAST GUARD... Proceedings § 1.07-100 Summons in lieu of seizure of commercial fishing industry vessels. (a) As used in this section, the following terms have the meanings specified: (1) Commercial fishing industry vessel means a...

Hydrodynamic starvation in first-feeding larval fishes

PubMed Central

China, Victor; Holzman, Roi

2014-01-01

Larval fishes suffer prodigious mortality rates, eliminating 99% of the brood within a few days after first feeding. Hjort (1914) famously attributed this “critical period” of low survival to the larvae’s inability to obtain sufficient food [Hjort (1914) Rapp P-v Réun Cons Int Explor Mer 20:1–228]. However, the cause of this poor feeding success remains to be identified. Here, we show that hydrodynamic constraints on the ubiquitous suction mechanism in first-feeding larvae limit their ability to capture prey, thereby reducing their feeding rates. Dynamic-scaling experiments revealed that larval size is the primary determinant of feeding rate, independent of other ontogenetic effects. We conclude that first-feeding larvae experience “hydrodynamic starvation,” in which low Reynolds numbers mechanistically limit their feeding performance even under high prey densities. Our results provide a hydrodynamic perspective on feeding of larval fishes that focuses on the physical properties of the larvae and prey, rather than on prey concentration and the rate of encounters. PMID:24843180

Seasonal variation of assemblage and feeding guild structure of fish species in a boreal tidal basin

NASA Astrophysics Data System (ADS)

Kellnreitner, Florian; Pockberger, Moritz; Asmus, Harald

2012-08-01

Species composition, abundance, feeding relationships and guild structure of the fish assemblage in the Sylt-Rømø bight, a tidal basin in the northern Wadden Sea, were investigated to show seasonal differences and the importance of functional groups in this area. The tidal flats and in shallow subtidal areas were sampled using a beach seine and a bottom trawl net was used for deeper subtidal areas and tidal gullies. Species richness of fish was highest in summer where 26 species were caught, while the lowest richness was recorded in winter (17 species). Clear differences in species richness and abundance were found between shallow areas and deeper parts of the bight. Clupea harengus and Ammodytes tobianus were the most abundant species in deeper areas, while Pomatoschistus microps and Pomatoschistus minutus dominated shallower waters. Gut contents of 27 fish species were identified and the guild structure analyzed by UPGMA clustering of niche overlaps. Calanoid copepods (19.9%), Crangon crangon (18.2%) and mysid shrimps (8.4%) were the most abundant prey items of all fish species combined. Seven feeding guilds were present in the fall and winter, and eight and six in spring and summer, respectively. Fish feeding on calanoid copepods and C. crangon were present year round, whereas the occurrence of other guilds varied between seasons. Species composition of prey changed through seasons and, for some fish species, even the feeding mode itself varied with season. Most noticeable, 11 fish species changed guilds between seasons. We found a convergence in summer towards abundant prey items, whereas in winter diet overlap was lower. This is the first investigation of guild structure of almost all fish species present in a Wadden Sea area, and shows that consideration of seasonal differences is essential when determining feeding relationships of fish in temperate areas.

[Selective feeding in fish: Effect of feeding and defensive motivations evoked by natural odors].

PubMed

Kasumyan, A O; Marusov, E A

2015-01-01

The effect of feeding and defensive motivations evoked by natural olfactory signals (the food odor, the alarm pheromone) on choice and consumption of food items different in color and taste, and the manifestation of foraging behavior were examined in fish (koi Cyprinus carpio, roach Rutilus rutilus). The agar-agar pellets of red and green color having one of the amino acids (glycine, L-proline, L-alanine; all in concentration of 0.1 M) were simultaneously offered to single fishes in pure water, and in water extract of Chironomidae larvae or in water extract of fish skin. It was found out that odors used have different effects on fish foraging activity and on pellet selection for both pellet choice and consumption. On background of food odor, fish grasped pellets more often than in pure water. The equal choice of red and green pellets in pure water shifted to the preference of red ones in the presence of food odor. Despite the increase in the absolute number of pellets grasped, the relative consumption reduced and was replaced by selective consumption of pellets with glycine regardless of their color. Increasing demand for the food quality, due to the increased feeding motivation in response to food odor, is an important adaptation enhancing selection and consumption of food with more appropriate sensory qualities for fish. Defensive motivation caused by alarm pheromone suppressed predisposition. of fish to feed. Fish grasped pellets several times less often than in pure water and refused most of them. Any changes in the color or taste preferences were absent. Feeding behavior of fish of both species was characterized by repeated intraoral pellet testing, but in koi handling was less typical than in roach. In both species, handling activity was higher in those cases when the pellet was finally rejected. This activity was enhanced also on the background of food odor.

Feeding habits and trophic level of the Panama grunt Pomadasys panamensis, an important bycatch species from the shrimp trawl fishery in the Gulf of California.

PubMed

Rodríguez-Preciado, José A; Amezcua, Felipe; Bellgraph, Brian; Madrid-Vera, Juan

2014-01-01

The Panama grunt is an abundant and commercially important species in the southeastern Gulf of California, but the research undertaken on this species is scarce despite its ecological and economic importance. We studied the feeding habits of Panama grunt through stomach content analyses as a first step towards understanding the biology of this species in the study area. Our results indicate that the Panama grunt is a benthic predator throughout its life cycle and feeds mainly on infaunal crustaceans. Diet differences among grunt were not found according to size, diet, or season. Shannon diversity index results indicate that Panama grunt has a limited trophic niche breadth with a diet dominated by a limited number of taxa as crustaceans. The estimated trophic level of this species is 3.59. Overall, the Panama grunt is a carnivorous fish occupying the intermediate levels of the trophic pyramid.

Identification of specific bovine blood biomarkers with a non-targeted approach using HPLC ESI tandem mass spectrometry.

PubMed

Lecrenier, M C; Marbaix, H; Dieu, M; Veys, P; Saegerman, C; Raes, M; Baeten, V

2016-12-15

Animal by-products are valuable protein sources in animal nutrition. Among them are blood products and blood meal, which are used as high-quality material for their beneficial effects on growth and health. Within the framework of the feed ban relaxation, the development of complementary methods in order to refine the identification of processed animal proteins remains challenging. The aim of this study was to identify specific biomarkers that would allow the detection of bovine blood products and processed animal proteins using tandem mass spectrometry. Seventeen biomarkers were identified: nine peptides for bovine plasma powder; seven peptides for bovine haemoglobin powder, including six peptides for bovine blood meal; and one peptide for porcine blood. They were not detected in several commercial compound feed or feed materials, such as blood by-products of other animal origins, milk-derived products and fish meal. These biomarkers could be used for developing a species-specific and blood-specific detection method. Copyright © 2016 Elsevier Ltd. All rights reserved.

Feeding habits and trophic level of the Panama grunt Pomadasys panamensis, an important bycatch species from the shrimp trawl fishery in the Gulf of California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rodriguez-Preciado, Jose A.; Amezcua-Martinez, Felipe; Bellgraph, Brian J.

The Panama grunt is an abundant and commercially important species in the SE Gulf of California, but the research undertaken on this species is scarce despite its ecological and economic importance. We studied the feeding habits of Panama grunt through stomach content analyses as a first step towards understanding the biology of this species in the study area. Our results show that the Panama grunt is a benthic predator throughout its life cycle and feeds mainly on infaunal crustaceans. Diet differences were not found according to size, diet or season. Shannon diversity index results indicate that Panama grunt have amore » limited trophic niche breadth with a diet dominated by a limited number of taxa. The estimated trophic level of this species is 3.59. Overall, the Panama grunt is a carnivorous fish occupying the intermediate levels of the trophic pyramid.« less

Facilitation and Dominance in a Schooling Predator: Foraging Behavior of Florida Pompano, Trachinotus carolinus

PubMed Central

2015-01-01

Presumably an individual’s risk of predation is reduced by group membership and this ‘safety in numbers’ concept has been readily applied to investigations of schooling prey; however, foraging in groups may also be beneficial. We tested the hypothesis that, when feeding in groups, foraging of a coastal fish (Florida Pompano, Trachinotus carolinus) on a benthic prey source would be facilitated (i.e. fish feeding in groups will consume more prey items). Although this question has been addressed for other fish species, it has not been previously addressed for Florida Pompano, a fish known to exhibit schooling behavior and that is used for aquaculture, where understanding the feeding ecology is important for healthy and efficient grow-out. In this experiment, juvenile Florida Pompano were offered a fixed number of coquina clams (Donax spp.) for one hour either in a group or as individuals. The following day they were tested in the opposite configuration. Fish in groups achieved greater consumption (average of 26 clams consumed by the entire group) than the individuals comprising the group (average of 14 clams consumed [sum of clams consumed by all individuals of the group]). Fish in groups also had fewer unsuccessful foraging attempts (2.75 compared to 4.75 hr-1) and tended to have a shorter latency until the first feeding activity. Our results suggest fish in groups were more comfortable feeding and more successful in their feeding attempts. Interestingly, the consumption benefit of group foraging was not shared by all – not all fish within a group consumed equal numbers of clams. Taken together, the results support our hypothesis that foraging in a group provides facilitation, but the short-term benefits are not equally shared by all individuals. PMID:26068114

Seasonal variability of rocky reef fish assemblages: Detecting functional and structural changes due to fishing effects

NASA Astrophysics Data System (ADS)

Henriques, Sofia; Pais, Miguel Pessanha; Costa, Maria José; Cabral, Henrique Nogueira

2013-05-01

The present study analyzed the effects of seasonal variation on the stability of fish-based metrics and their capability to detect changes in fish assemblages, which is yet poorly understood despite the general idea that guilds are more resilient to natural variability than species abundances. Three zones subject to different levels of fishing pressure inside the Arrábida Marine Protected Area (MPA) were sampled seasonally. The results showed differences between warm (summer and autumn) and cold (winter and spring) seasons, with the autumn clearly standing out. In general, the values of the metrics density of juveniles, density of invertebrate feeders and density of omnivores increased in warm seasons, which can be attributed to differences in recruitment patterns, spawning migrations and feeding activity among seasons. The density of generalist/opportunistic individuals was sensitive to the effect of fishing, with higher values at zones with the lowest level of protection, while the density of individuals with high commercial value only responded to fishing in the autumn, due to a cumulative result of both juveniles and adults abundances during this season. Overall, this study showed that seasonal variability affects structural and functional features of the fish assemblage and that might influence the detection of changes as a result of anthropogenic pressures. The choice of a specific season, during warm sea conditions after the spawning period (July-October), seems to be more adequate to assess changes on rocky-reef fish assemblages.

Selenium Nanoparticles for Stress-Resilient Fish and Livestock

NASA Astrophysics Data System (ADS)

Sarkar, Biplab; Bhattacharjee, Surajit; Daware, Akshay; Tribedi, Prosun; Krishnani, K. K.; Minhas, P. S.

2015-09-01

The fisheries and livestock sectors capture the highest share of protein-rich animal food and demonstrate accelerated growth as an agriculture subsidiary. Environmental pollution, climate change, as well as pathogenic invasions exert increasing stress impacts that lead the productivity momentum at a crossroads. Oxidative stress is the most common form of stress phenomenon responsible for the retardation of productivity in fisheries and livestock. Essential micronutrients play a determinant role in combating oxidative stress. Selenium, one of the essential micronutrients, appears as a potent antioxidant with reduced toxicity in its nanoscale form. In the present review, different methods of synthesis and characterization of nanoscale selenium have been discussed. The functional characterization of nano-selenium in terms of its effect on growth patterns, feed digestibility, and reproductive system has been discussed to elucidate the mechanism of action. Moreover, its anti-carcinogenic and antioxidant potentiality, antimicrobial and immunomodulatory efficacy, and fatty acid reduction in liver have been deciphered as the new phenomena of nano-selenium application. Biologically synthesized nano-selenium raises hope for pharmacologically enriched, naturally stable nanoscale selenium with high ecological viability. Hence, nano-selenium can be administered with commercial feeds for improvising stress resilience and productivity of fish and livestock.

Effects of temperature and diet on the growth rate of year 0 oyster toadfish, Opsanus tau.

PubMed

Mensinger, A F; Tubbs, M E

2006-02-01

The effects of temperature and diet on the growth of captive year 0 specimens of Opansus tau were examined for two consecutive year classes. The 2001 year class was raised at about 23, 26, or 29 degrees C and provided with live brine shrimp, frozen butterfish and squid, or commercial food pellets (45% protein, 19% fat, and 3% fiber) three times per week. Maximal growth was achieved with the pellet diet, and fish raised at 29 degrees C attained the highest mean wet weight (84.0 g +/- 14.6 g SE) and fastest instantaneous relative growth rate (IRGR, 1.79% body weight/d). The 2002 year class was raised on the same pellet diet at 31.5 degrees C and fed 3, 5, or 7 times per week. Although more frequent feedings led to significantly greater mean wet weight in the first half of the year, by month 12 there was no significant difference between the three feeding frequencies. These fish weighed approximately 68 g and had an average IRGR of 1.74% body weight/d. The pellet diet during both years was correlated with high survival (> 75%).

Selenium Nanoparticles for Stress-Resilient Fish and Livestock.

PubMed

Sarkar, Biplab; Bhattacharjee, Surajit; Daware, Akshay; Tribedi, Prosun; Krishnani, K K; Minhas, P S

2015-12-01

The fisheries and livestock sectors capture the highest share of protein-rich animal food and demonstrate accelerated growth as an agriculture subsidiary. Environmental pollution, climate change, as well as pathogenic invasions exert increasing stress impacts that lead the productivity momentum at a crossroads. Oxidative stress is the most common form of stress phenomenon responsible for the retardation of productivity in fisheries and livestock. Essential micronutrients play a determinant role in combating oxidative stress. Selenium, one of the essential micronutrients, appears as a potent antioxidant with reduced toxicity in its nanoscale form. In the present review, different methods of synthesis and characterization of nanoscale selenium have been discussed. The functional characterization of nano-selenium in terms of its effect on growth patterns, feed digestibility, and reproductive system has been discussed to elucidate the mechanism of action. Moreover, its anti-carcinogenic and antioxidant potentiality, antimicrobial and immunomodulatory efficacy, and fatty acid reduction in liver have been deciphered as the new phenomena of nano-selenium application. Biologically synthesized nano-selenium raises hope for pharmacologically enriched, naturally stable nanoscale selenium with high ecological viability. Hence, nano-selenium can be administered with commercial feeds for improvising stress resilience and productivity of fish and livestock.

36 CFR 13.1134 - Who is eligible for a Glacier Bay commercial fishing lifetime access permit?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Who is eligible for a Glacier... Regulations-Glacier Bay National Park and Preserve Commercial Fishing § 13.1134 Who is eligible for a Glacier Bay commercial fishing lifetime access permit? A Glacier Bay commercial fishing lifetime access permit...

36 CFR 13.1134 - Who is eligible for a Glacier Bay commercial fishing lifetime access permit?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Who is eligible for a Glacier... Regulations-Glacier Bay National Park and Preserve Commercial Fishing § 13.1134 Who is eligible for a Glacier Bay commercial fishing lifetime access permit? A Glacier Bay commercial fishing lifetime access permit...

36 CFR 13.1134 - Who is eligible for a Glacier Bay commercial fishing lifetime access permit?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Who is eligible for a Glacier... Regulations-Glacier Bay National Park and Preserve Commercial Fishing § 13.1134 Who is eligible for a Glacier Bay commercial fishing lifetime access permit? A Glacier Bay commercial fishing lifetime access permit...

36 CFR 13.1134 - Who is eligible for a Glacier Bay commercial fishing lifetime access permit?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Who is eligible for a Glacier... Regulations-Glacier Bay National Park and Preserve Commercial Fishing § 13.1134 Who is eligible for a Glacier Bay commercial fishing lifetime access permit? A Glacier Bay commercial fishing lifetime access permit...

Potential changes in feeding behavior of Antarctic fish, Pseudotrematomus bernacchii (Boulenger, 1902) on the East Ongul Island, Antarctica

NASA Astrophysics Data System (ADS)

Chavanich, Suchana; Viyakarn, Voranop; Nomura, Daiki; Watanabe, Kentaro

2015-12-01

The feeding habits of the Antarctic fish Pseudotrematomus bernacchii (Previous name: Trematomus bernacchii) under the fast ice around Japanese Syowa Station were investigated in the summers of 2004/2005 and 2009/2010. The results showed that amphipods and krill were the major prey. However, there was a significant difference in the proportions of larger invertebrates such as squids, octopus and other crustaceans found in the fish stomachs between 2009/2010 and the previous years. Moreover, the percentage of amphipods and krill in fish stomachs declined over the 5-year period in all fish size classes. Several factors including sea ice melting, habitat and environmental changes might have influenced the pattern of feeding behavior.

Isotopic structure of Lake Whitefish in Lake Huron: Evidence for regional and local populations based on resource use

USGS Publications Warehouse

Eberts, Rebecca L.; Wissel, Bjorn; Simpson, Gavin L.; Crawford, Stephen S.; Stott, Wendylee; Hanner, Robert H.; Manzon, Richard G.; Wilson, Joanna Y.; Boreham, Douglas R.; Somers, Christopher M.

2017-01-01

Lake Whitefish Coregonus clupeaformis is the most commercially valuable species in Lake Huron. The fishery for this species has historically been managed based on 25 management units (17 in Canada, 8 in the USA). However, congruence between the contemporary population structure of Lake Whitefish and management units is poorly understood. We used stable isotopes of carbon (δ13C) and nitrogen (δ15N), food web markers that reflect patterns in resource use (i.e., prey, location, habitat), to assess the population structure of spawning-phase Lake Whitefish collected from 32 sites (1,474 fish) across Lake Huron. We found large isotopic variation among fish from different sites (ranges: δ13C = 10.2‰, δ15N = 5.5‰) and variable niche size and levels of overlap (standard ellipse area = 1.0–4.3‰2). Lake Huron contained spawning-phase fish from four major isotopic clusters largely defined by extensive variation in δ13C, and the isotopic composition of fish sampled was spatially structured both within and between lake basins. Based on cluster compositions, we identified six putative regional groups, some of which represented sites of high diversity (three to four clusters) and others with less (one to two clusters). Analysis of isotopic values from Lake Whitefish collected from summer feeding locations and baseline prey items showed similar isotopic variation and established spatial linkage between spawning-phase and summer fish. Our results show that summer feeding location contributes strongly to the isotopic structure we observed in spawning-phase fish. One of the regional groups we identified in northern Georgian Bay is highly distinct based on isotopic composition and possibly ecologically unique within Lake Huron. Our findings are congruent with several previous studies using different markers (genetics, mark–recapture), and we conclude that current management units are generally too small and numerous to reflect the population structure of Lake Whitefish in Lake Huron.

Somatic growth effects of intramuscular injection of growth hormone in androgen-treated juvenile Nile tilapia, Oreochromis niloticus (Perciformes: Cichlidae).

PubMed

Liñán-Cabello, Marco A; Robles-Basto, Cindy M; Mena-herrera, Alfredo

2013-03-01

Little is known about the effects of the interaction of growth hormone (GH) with 17 alpha-methyltestosterone (17-MT) during fish growth. We evaluated this in the present study to assess the effect on fish growth. Fish in two batches of juvenile tilapia (Oreochromis niloticus) (approximately 5.0cm in length) were randomly assigned in triplicate to three treatments and a control group, distributed among 12 fiberglass tanks of 1 000L capacity (50 fish per tank) in an experiment covering a period of six weeks. The experimental groups were: a) fish treated with 17-MT and GH in mineral oil (RGH); b) fish treated with 17-MT and mineral oil without the addition of GH (R); c) fish treated with GH in mineral oil but not 17-MT (NGH); and d) fish of the control group, which were treated with mineral oil but not 17-MT or GH (N). The GH was injected into the fish at a rate of 0.625mg/g body weight. Morphometric data were recorded at the beginning of the experiment (T0) and at 15, 30 and 45 days (T15, T30 and T45), and various indicators of growth were assessed: condition factor (K); survival percentage (S), feed conversion rate (FCR), percentage weight gain (WG) and (v) daily weight gain. The optimum dietary level was calculated assuming 5% food conversion to total weight in each group. During the experiment, the fish were provided with a commercial food containing 45% protein. The data showed that GH injection resulted in a greater weight gain in fish treated with 17-MT (the RGH treatment group), being particularly significant increase in weight during T15 and T30 (p<0.05). High values of K were found in the R and RGH treatments during the initial days of the experiment, which may have been a consequence of the better nutritional status affecting both weight gain and growth in body length, as a result of the additive effects of 17-MT and GH. The fish in groups not treated with 17-MT and treated with 17-MT and added GH showed greater increases in WG per day, higher K values and lower FCRs than fish in the other groups, which suggests that greater feed efficiency occurred in the hormone-treated fish. Fish in the RGH treatment showed the most growth, suggesting a possible interaction between 17-MT and injected GH.

Foraging Behaviour Patterns of Four Sympatric Demersal Fishes

NASA Astrophysics Data System (ADS)

Labropoulou, M.; Papadopoulou-Smith, K.-N.

1999-08-01

The trophic relationships of four sympatric demersal fish species (Mullus barbatus, Mullus surmuletus, Pagrus pagrus and Gobius niger) which dominate the shallow coastal areas (25-30 m) of Iraklion Bay (S Aegean, NE Mediterranean) were investigated from samples collected on a monthly basis (August 1990-August 1992). Stomach content analysis revealed that all four species were carnivorous, feeding mainly on benthic invertebrates. Although these species displayed different feeding modes based on principal prey type utilization, they all consumed a considerable number of polychaetes. In order to understand any underlying patterns of predation on polychaetes, prey items were identified to the lowest possible taxonomic level. The polychaete species were further classified into groups according to their microhabitat (surface or burrowing) and feeding (feeding mode, motility and morphology) guilds. Comparisons of the feeding habits were made using the percentage contribution by number of each prey species in the diet of the predators. Similarities in the diets between the fish species were calculated and cluster analysis was used to describe interspecific variations in food selection, concerning polychaetes. The predatory preferences of each fish species were related to the microhabitat distribution of prey species in the sediment. The differential exploitation of polychaete species was a good indicator of disparate foraging behaviour among the fish species examined, since it reflects a transition from a non-selective to a specialized feeding method. The effects of predator size and morphology of feeding apparatus and the availability of polychaete species in the environment are also discussed to explain the differential exploitation of polychaetes exhibited by the fish.

Oral DNA vaccines based on CS-TPP nanoparticles and alginate microparticles confer high protection against infectious pancreatic necrosis virus (IPNV) infection in trout.

PubMed

Ahmadivand, Sohrab; Soltani, Mehdi; Behdani, Mahdi; Evensen, Øystein; Alirahimi, Ehsan; Hassanzadeh, Reza; Soltani, Ellahe

2017-09-01

Infectious pancreatic necrosis virus (IPNV) is the etiological agent of a contagious viral disease causing remarkable mortalities in different fish species. Despite the availability of commercial vaccines against IPN, the disease still constitutes one of the main threats to the aquaculture industry worldwide. In this study, we developed a DNA vaccine encoding the VP2 gene of IPNV and evaluated its ability to induce protective immunity in rainbow trout fry (3 g) at doses of 10 and 25 μg/fish and boosting with the same doses two weeks later through the oral route using chitosan/tripolyphosphate (CS-TPP) nanoparticles and alginate microparticles incorporated into fish feed. The distribution of the administered vaccines in different organs and transcription of VP2 gene were confirmed by RT-PCR assay at day 30 post boost-vaccination. Transcript levels of IFN-1, Mx-1, IgM, IgT and CD4 genes was dependent on vaccine dose and was significantly up-regulated in head kidney of all orally vaccinated fish groups compared to controls (pcDNA3.1). Cumulative mortalities post-challenge with virulent isolate of the virus were lower in the vaccinated fish and a relative percentage survival (RPS) of 59% and 82% were obtained for the 10 and 25 μg/fish pcDNA3.1-VP2 groups, respectively. Vaccination with the same amount of pcDNA3.1-VP2 encapsulated with CS-TPP nanoparticles resulted in RPS of 47 %and 70%, respectively. Detectable anti-IPNV antibodies were shown until 90 days postvaccination. The orally administrated vaccines significantly decreased VP4 transcripts thus contributing to reducing viral load in surviving fish on day 45 post-challenge. In conclusion, these results show good to high protection post-vaccination alongside with significant up-regulation of key immune genes and detectable levels of circulating antibodies after oral administration of the DNA vaccine formulated in CS-TPP nanoparticles and alginate microparticles in fish feed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dietary Aloe vera supplementation on growth performance, some haemato-biochemical parameters and disease resistance against Streptococcus iniae in tilapia (GIFT).

PubMed

Gabriel, Ndakalimwe Naftal; Qiang, Jun; He, Jie; Ma, Xin Yu; Kpundeh, Mathew D; Xu, Pao

2015-06-01

This study investigated effects of dietary Aloe vera on growth performance, some haemato-biochemical parameters and disease resistance against Streptococcus iniae in tilapia (GIFT). Five groups were designed including a basal diet (control) and 100% A. vera powder incorporated in fish feed at 0.5% 1%, 2%, and 4%/kg feed, which were administered for 8 weeks. Fish fed 0.5%, 1%, and 2% A. vera supplemented diet significantly improved (p < 0.05) weight gain, absolute growth rate and specific growth rate. Feed intake significantly increased in fish fed with A. vera diet at 1% and 2%/kg feed. Feed efficiency ratio, feed conversion ratio, and hepatosomatic index were significantly enhanced in 4% A. vera supplemented fish over unsupplemented ones (p < 0.05). Several haemato-biochemical indices were examined before and after fish were challenged with S. iniae pathogen containing 7.7 × 10(6) CFU cells mL(-1). A. vera supplemented fish showed a significant increase (p < 0.05) in red blood cells, hematocrits (Hb), hemoglobin (Hb), white blood cells (WBC), neutrophils, monocytes, eosinophils, serum total protein, glucose and cortisol after challenge when compared to unsupplemented ones. Meanwhile, 4% A. vera supplemented fish showed a decrease (p < 0.05) in RBC, Hb, Ht, WBC, and mean corpuscular hemoglobin (MCH) after challenge compared to unsupplemented ones and other supplemented ones. In addition, lower mean corpuscular volume values (MCV) (p < 0.05) were observed in fish fed with A. vera diet at 2% and 4% A. vera/kg feed than those fed unsupplemented diet. Unchallenged fish fed 0.5%, 1%, and 2% A. vera showed significantly higher values (p < 0.05) of mean corpuscular hemoglobin concentration (MCHC) than those fed unsupplemented diet and 4% A. vera supplemented diet. There was a significant increase (p < 0.05) in the neutrophil to lymphocyte ratio (N/L) within experimental groups after challenge; N/L ratio in A. vera unsupplemented fish and those supplemented with A. vera diet at 1%/kg feed increased significantly (p < 0.05) throughout challenge period; while those fed 4% A. vera supplemented diet maintained higher values at all experimental stages among groups. There was a significant correlation (p < 0.05, r = 0.53) between N/L ratio and glucose concentration, 96 h after challenge. Aloe had no significant effect (p > 0.05) on the survival of the fish when compared to the control; no mortality was recorded in challenge trial. Overall, our results indicated that dietary aloe supplementation could improve growth, feed utilization, and haemato-biochemical parameters of cultured tilapia. Copyright © 2015 Elsevier Ltd. All rights reserved.

Depletion of florfenicol amine, marker residue of florfenicol, from the edible fillet of tilapia (Oreochromis niloticus x O. niloticus and O. niloticus x O. aureus) following florfenicol administration in feed

USGS Publications Warehouse

Gaikowski, M.P.; Mushtaq, M.; Cassidy, P.; Meinertz, J.R.; Schleis, S.M.; Sweeney, D.; Endris, R.G.

2010-01-01

Aquaflor??, a 50% feed premix containing the broad spectrum antibacterial agent florfenicol is available globally to control mortality associated with economically significant systemic bacterial diseases of fish. Florfenicol (FFC) is effective in controlling mortality associated with Streptococcus iniae in tilapia Oreochromis sp. when administered in medicated feed at a dose of 15 mg/kg bodyweight (BW)/d for 10 consecutive days. Our objective was to characterize the depletion of the FFC marker residue, florfenicol amine (FFA), from the edible tissue of market-weight Nile tilapia O. niloticus x O. niloticus and hybrid tilapia O. niloticus x O. aureus offered feed medicated with FFC at a nominal dose rate of 15 mg/kg BW/d for 12 days. Near market-weight tilapia were obtained from a commercial tilapia farm, distributed to 2 single pass (one for Nile tilapia and one for hybrid tilapia), flow-through systems and maintained at 27 ??C under a 15 h light:9 h dark photoperiod over a 41-d pre-dosing period. During the dosing period, tilapia were offered feed medicated with FFC at a concentration of 1.479 g/kg at 1% BW daily divided in three equal offerings. The initial 10-d dosing period was extended to 12 d because one tank did not consume > 75% of the feed offered during the first two dosing days. The total dose consumed by fish in each of the 2 tanks ranged from 147 to 167 mg/kg. Once during the pre-dose period and on days 1, 2, 4, 7, 14, 21, and 28 of the post-dose period, groups of fish were indiscriminately removed from each tank, measured for weight and length, scaled, filleted, and the skin-on fillets stored at <-70 ??C. Frozen fillets were individually homogenized, extracted, and FFA concentration was determined by high-performance liquid chromatography with UV detection. Florfenicol amine is rapidly eliminated from tilapia fillet after withdrawal from medication and depletion followed first-order kinetics with an estimated half-life of 2.32 d. The FFA tolerance limit, calculated as the 99th percentile of the potential residue level at 95% confidence, had depleted to less than the 1 ??g/g maximum residue level by 6.14 d after the dosing period.

Novel approach for the simultaneous detection of DNA from different fish species based on a nuclear target: quantification potential.

PubMed

Prado, Marta; Boix, Ana; von Holst, Christoph

2012-07-01

The development of DNA-based methods for the identification and quantification of fish in food and feed samples is frequently focused on a specific fish species and/or on the detection of mitochondrial DNA of fish origin. However, a quantitative method for the most common fish species used by the food and feed industry is needed for official control purposes, and such a method should rely on the use of a single-copy nuclear DNA target owing to its more stable copy number in different tissues. In this article, we report on the development of a real-time PCR method based on the use of a nuclear gene as a target for the simultaneous detection of fish DNA from different species and on the evaluation of its quantification potential. The method was tested in 22 different fish species, including those most commonly used by the food and feed industry, and in negative control samples, which included 15 animal species and nine feed ingredients. The results show that the method reported here complies with the requirements concerning specificity and with the criteria required for real-time PCR methods with high sensitivity.

7 CFR 760.206 - Notice of loss and application process.

Code of Federal Regulations, 2011 CFR

2011-01-01

..., Honeybees, and Farm-Raised Fish Program § 760.206 Notice of loss and application process. (a) To apply for ELAP, the participant that suffered eligible livestock, honeybee, or farm-raised fish losses must... Application; (ii) For honeybee feed, honeybee colony, honeybee hive, or farm-raised fish feed or death losses...

Insect-based protein: future promising protein source for fish cultured

NASA Astrophysics Data System (ADS)

Nugroho, R. A.; Nur, F. M.

2018-04-01

As one of the vital component feed used in fisheries, fishmeal (FM) is generally added to the fish diet to enhance fish growth, digestive performance and absorption of nutrients. This addition contributes significantly to the variable production cost in the aquaculture industry. Expanded production of carnivorous species requiring high protein, high-energy feeds will further tax global fish meal. Thus, research based on the low-cost budget for feed operating cost should be strategized to assist aquaculturists in enhancing fish productivity. Moreover, suitable alternative feed ingredients will have to be utilized to provide the essential nutrients and energy needed to fuel the growth of aquaculture production. To this effect, the use of insect-based protein sources to replace FM that often scarce, expensive, limited availability, and leads to high fish production costs is alternative ways and has been gaining momentum. Currently, Insects have been proposed as one of the potential future protein sources of protein because of the production of insects is highly sustainable. Farming insects is characterized by higher food conversion efficiencies, lower environmental impact, and higher potential to be grown on waste streams.

Feeding ecology of pelagic fish species in the Gulf of Riga (Baltic Sea): the importance of changes in the zooplankton community.

PubMed

Lankov, A; Ojaveer, H; Simm, M; Põllupüü, M; Möllmann, C

2010-12-01

The feeding ecology of four pelagic fish species was studied in relation to their prey availability in the Gulf of Riga (Baltic Sea) during the summer 1999-2006. The zooplankton community was dominated by the cladoceran Bosmina longispina, rotifers Keratella cochlearis and K. quadrata and the copepod Eurytemora affinis, with the highest interannual variability in abundance recorded for B. longispina. The last influenced the diet of adult sprat Sprattus sprattus, juvenile smelt Osmerus eperlanus and three-spined stickleback Gasterosteus aculeatus as these were strongly selecting for B. longispina. The fish feeding activity did not match the abundance dynamics of their preferred prey, suggesting that fishes may switch to consume other prey in case the preferred diet was limited. A considerable dietary overlap indicated high potential competition between pelagic fish species. While herring Clupea harengus membras and G. aculeatus were relying on very different food, the diets of young O. eperlanus and G. aculeatus were very similar. Interannual variability in zooplankton composition and abundance significantly affected the diet composition of fishes, but those changes were insufficient to exert a consistent influence upon fish feeding activity and total amounts of zooplankton consumed. © 2010 The Authors. Journal of Fish Biology © 2010 The Fisheries Society of the British Isles.

Evaluation of emamectin benzoate for the control of experimentally induced infestations of Argulus sp. in goldfish and koi carp.

PubMed

Hanson, Shari K; Hill, Jeffrey E; Watson, Craig A; Yanong, Roy P E; Endris, Richard

2011-03-01

The effect of 0.2% emamectin benzoate (SLICE; Intervet/ Schering-Plough Animal Health, Roseland, New Jersey) administered in top-dressed, pelleted commercial fish feed was evaluated for control of freshwater Argulus sp. in goldfish Carassius auratus and koi carp, a variant of common carp Cyprinus carpio, in freshwater aquaria at 24-25 degrees C. Sixteen individually housed goldfish were each exposed to 37 Argulus. The number of fish lice attached to each fish at the start of the experiment was not determined; however, the total number of motile fish lice in each aquarium (on fish and in the water) was determined at the start and end of each experiment. Eight goldfish were fed the control diet (0 microg x kg fish biomass(-1) x d(-1)) and eight were fed the medicated diet (50 microg x kg fish biomass(-1) x d(-1)) for seven consecutive days. After treatment, fish louse infestation in controls was 20.5 +/- 1.5 (mean +/- SE) lice per fish. No Argulus were found on fish in the treated group. In a separate experiment, 10 individually housed koi were each exposed to 128 Argulus. Five koi were fed the control diet and five were fed a low-dose medicated diet (5 microg x kg fish biomass(-1) x d(-1)) for 7 d. After treatment, fish louse infestation among the controls was 14.6 +/- 3.8 lice per koi. No Argulus were found on koi in the treated group. Hence, a 7-d regimen of oral emamectin benzoate controlled experimental infestation of Argulus when administered to goldfish at 50 microg x kg fish biomass(-1) x d(-1) and to koi at 5 microg x kg fish biomass(-1) x d(-1).

Dominance behaviour in a non-aggressive flatfish, Senegalese sole (Solea senegalensis) and brain mRNA abundance of selected transcripts.

PubMed

Fatsini, Elvira; Rey, Sonia; Ibarra-Zatarain, Zohar; Mackenzie, Simon; Duncan, Neil J

2017-01-01

Dominance is defined as the preferential access to limited resources. The present study aimed to characterise dominance in a non-aggressive flatfish species, the Senegalese sole (Solea senegalensis) by 1) identifying dominance categories and associated behaviours and 2) linking dominance categories (dominant and subordinate) with the abundance of selected mRNA transcripts in the brain. Early juveniles (n = 74, 37 pairs) were subjected to a dyadic dominance test, related to feeding, and once behavioural phenotypes had been described the abundance of ten selected mRNAs related to dominance and aggressiveness was measured in the brain. Late juveniles were subjected to two dyadic dominance tests (n = 34, 17 pairs), related to feeding and territoriality and one group test (n = 24, 4 groups of 6 fish). Sole feeding first were categorized as dominant and sole feeding second or not feeding as subordinate. Three social behaviours (i. "Resting the head" on another fish, ii. "Approaching" another fish, iii. "Swimming above another" fish) were associated with dominance of feeding. Two other variables (i. Total time occupying the preferred area during the last 2 hours of the 24 h test, ii. Organisms occupying the preferred area when the test ended) were representative of dominance in the place preference test. In all tests, dominant fish compared to subordinate fish displayed a significantly higher number of the behaviours "Rest the head" and "Approaches". Moreover, dominant sole dominated the sand at the end of the test, and in the group test dominated the area close to the feed delivery point before feed was delivered. The mRNA abundance of the selected mRNAs related to neurogenesis (nrd2) and neuroplasticity (c-fos) in dominant sole compared to subordinate were significantly different. This is the first study to characterise dominance categories with associated behaviours and mRNA abundance in Senegalese sole and provides tools to study dominance related problems in feeding and reproduction in aquaculture.

Hybrid striped bass feeds based on fish oil, beef tallow, and eicosapentaenoic acid/docosahexaenoic acid supplements: Insight regarding fish oil sparing and demand for -3 long-chain polyunsaturated fatty acids.

PubMed

Bowzer, J; Jackson, C; Trushenski, J

2016-03-01

Previous research suggests that saturated (SFA) and monounsaturated fatty acid (MUFA) rich lipids, including beef tallow, can make utilization or diet-to-tissue transfer of long-chain polyunsaturated fatty acids (LC-PUFA) more efficient. We hypothesized that using beef tallow as an alternative to fish oil may effectively reduce the LC-PUFA demand of hybrid striped bass × and allow for greater fish oil sparing. Accordingly, we evaluated growth performance and tissue fatty acid profiles of juvenile fish (23.7 ± 0.3 g) fed diets containing menhaden fish oil (considered an ideal source of LC-PUFA for this taxon), beef tallow (BEEF ONLY), or beef tallow amended with purified sources of eicosapentaenoic acid (EPA) and/or docosahexaenoic acid (DHA) to achieve levels corresponding to 50 or 100% of those observed in the FISH ONLY feed. Diets were randomly assigned to quadruplicate tanks of fish ( = 4; 10 fish/tank), and fish were fed assigned diets to apparent satiation once daily for 10 wk. Survival (98-100%) was equivalent among treatments, but weight gain (117-180%), specific growth rate (1.1-1.5% BW/d), feed intake (1.4-1.8% BW/d), thermal growth coefficient (0.50-0.70), and feed conversion ratio (FCR; 1.1-1.4, DM basis) varied. Except for FCR, no differences were observed between the FISH ONLY and BEEF ONLY treatments, but performance was generally numerically superior among fish fed the diets containing beef tallow supplemented with DHA at the 100% or both EPA and DHA at the 50% or 100% level. Tissue fatty acid composition was significantly distorted in favor among fish fed the beef tallow-based feeds; however, profile distortion was most overt in peripheral tissues. Results suggest that beef tallow may be used as a primary lipid source in practical diets for hybrid striped bass, but performance may be improved by supplementation with LC-PUFA, particularly DHA. Furthermore, our results suggest that -3 LC-PUFA requirements reported for hybrid striped bass may not be fully accurate and that DHA may be more critical than EPA as a limiting nutrient in feed formulation.

Development, validation and accreditation of a method for the determination of Pb, Cd, Cu and As in seafood and fish feed samples.

PubMed

Psoma, A K; Pasias, I N; Rousis, N I; Barkonikos, K A; Thomaidis, N S

2014-05-15

A rapid, sensitive, accurate and precise method for the determination of Pb, Cd, As and Cu in seafood and fish feed samples by Simultaneous Electrothermal Atomic Absorption Spectrometry was developed in regard to Council Directive 333/2007EC and ISO/IEC 17025 (2005). Different approaches were investigated in order to shorten the analysis time, always taking into account the sensitivity. For method validation, precision (repeatability and reproducibility) and accuracy by addition recovery tests have been assessed as performance criteria. The expanded uncertainties based on the Eurachem/Citac Guidelines were calculated. The method was accredited by the Hellenic Accreditation System and it was applied for an 8 years study in seafood (n=202) and fish feeds (n=275) from the Greek market. The annual and seasonal variation of the elemental content and correlation among the elemental content in fish feeds and the respective fish samples were also accomplished. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of feed quality and quantity on growth, early maturation and smolt development in hatchery-reared landlocked Atlantic salmon Salmo salar.

PubMed

Norrgård, J R; Bergman, E; Greenberg, L A; Schmitz, M

2014-10-01

The effects of feed quality and quantity on growth, early male parr maturation and development of smolt characteristics were studied in hatchery-reared landlocked Atlantic salmon Salmo salar. The fish were subjected to two levels of feed rations and two levels of lipid content from first feeding until release in May of their second year. Salmo salar fed high rations, regardless of lipid content, grew the most and those fed low lipid feed with low rations grew the least. In addition, fish fed low lipid feed had lower body lipid levels than fish fed high lipid feed. Salmo salar from all treatments showed some reduction in condition factor (K) and lipid levels during their second spring. Smolt status was evaluated using both physiological and morphological variables. These results, based on gill Na(+) , K(+) -ATPase (NKA) enzyme activity, saltwater tolerance challenges and visual assessments, were consistent with each other, showing that S. salar from all treatments, except the treatment in which the fish were fed low rations with low lipid content, exhibited characteristics associated with smolting at 2 years of age. Sexually mature male parr from the high ration, high lipid content treatment were also subjected to saltwater challenge tests, and were found to be unable to regulate plasma sodium levels. The proportion of sexually mature male parr was reduced when the fish were fed low feed rations, but was not affected by the lipid content of the feed. Salmo salar fed low rations with low lipid content exhibited the highest degree of severe fin erosion. © 2014 The Fisheries Society of the British Isles.

The effects of mariculture on heavy metal distribution in sediments and cultured fish around the Pearl River Delta region, south China.

PubMed

Liang, Peng; Wu, Sheng-Chun; Zhang, Jin; Cao, Yucheng; Yu, Shen; Wong, Ming-Hung

2016-04-01

Thirty-six sediment samples were collected from six mariculture sites and corresponding reference sites (approximately 200-300 m away from each mariculture site) to study the effects of mariculture on heavy metal: copper (Cu), zinc (Zn), chromium (Cr) and lead (Pb) distribution in sediments and cultured fish around the Pearl River Delta region, south China. The mean concentrations of Cu, Zn, Cr and Pb in all mariculture sediment samples were 109, 273, 99 and 33 mg/kg, compared with 63, 209, 56 and 23 mg/kg for reference sediment samples, respectively. The Pollution Load Index of sediment for each site was over 1, implying substantial heavy metal pollution. The results of principal component analysis and hierarchical clustering analysis indicate that marine aquaculture activities have enriched the surface sediments underneath mariculture rafts with Cu, Zn and Pb, possibly due to the accumulation of unconsumed fish feeds, fish excreta and antifouling paints (except Cr). Two kinds of fish feeds, feed pellets and trash fish commonly used in Hong Kong were analyzed. The concentrations of Zn and Cu contained in feed pellets were significantly higher (p < 0.05) than in trash fish due to addition of these elements as growth promoters during pellet production. However, the Pb content in trash fish (due to contamination) was significantly higher (p < 0.05) than in feed pellets. Three cultured fish species, namely red snapper (Lutjanus campechanus), orange-spotted grouper (Epinephelus coioides) and snubnose pompano (Trachinotus blochii), were collected from each mariculture site for metal analysis. Lead concentrations in 21 fish samples exceeded the Chinese safety guideline (0.5 mg/kg, GB18406.4-2001), indicating that Pb contamination in cultured fish would be a public health concern. Copyright © 2015. Published by Elsevier Ltd.

Food consumption and digestion time estimation of spotted scat, Scatophagus argus, using X-radiography technique

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hashim, Marina; Abidin, Diana Atiqah Zainal; Das, Simon K.

The present study was conducted to investigate the food consumption pattern and gastric emptying time using x-radiography technique in scats fish, Scatophagus argus feeding to satiation in laboratory conditions. Prior to feeding experiment, fish of various sizes were examined their stomach volume, using freshly prepared stomachs ligatured at the tips of the burret, where the maximum amount of distilled water collected in the stomach were measured (ml). Stomach volume is correlated with maximum food intake (S{sub max}) and it can estimate the maximum stomach distension by allometric model i.e volume=0.0000089W{sup 2.93}. Gastric emptying time was estimated using a qualitative X-radiographymore » technique, where the fish of various sizes were fed to satiation at different time since feeding. All the experimental fish was feed into satiation using radio-opaque barium sulphate (BaSO{sub 4}) paste injected in the wet shrimp in proportion to the body weight. The BaSO{sub 4} was found suitable to track the movement of feed/prey in the stomach over time and gastric emptying time of scats fish can be estimated. The results of qualitative X-Radiography observation of gastric motility, showed the fish (200 gm) that fed to maximum satiation meal (circa 11 gm) completely emptied their stomach within 30 - 36 hrs. The results of the present study will provide the first baseline information on the stomach volume, gastric emptying of scats fish in captivity.« less

Food consumption and digestion time estimation of spotted scat, Scatophagus argus, using X-radiography technique

NASA Astrophysics Data System (ADS)

Hashim, Marina; Abidin, Diana Atiqah Zainal; Das, Simon K.; Ghaffar, Mazlan Abd.

2014-09-01

The present study was conducted to investigate the food consumption pattern and gastric emptying time using x-radiography technique in scats fish, Scatophagus argus feeding to satiation in laboratory conditions. Prior to feeding experiment, fish of various sizes were examined their stomach volume, using freshly prepared stomachs ligatured at the tips of the burret, where the maximum amount of distilled water collected in the stomach were measured (ml). Stomach volume is correlated with maximum food intake (Smax) and it can estimate the maximum stomach distension by allometric model i.e volume=0.0000089W2.93. Gastric emptying time was estimated using a qualitative X-radiography technique, where the fish of various sizes were fed to satiation at different time since feeding. All the experimental fish was feed into satiation using radio-opaque barium sulphate (BaSO4) paste injected in the wet shrimp in proportion to the body weight. The BaSO4 was found suitable to track the movement of feed/prey in the stomach over time and gastric emptying time of scats fish can be estimated. The results of qualitative X-Radiography observation of gastric motility, showed the fish (200 gm) that fed to maximum satiation meal (circa 11 gm) completely emptied their stomach within 30 - 36 hrs. The results of the present study will provide the first baseline information on the stomach volume, gastric emptying of scats fish in captivity.

Do invasive corals alter coral reef processes? An empirical approach evaluating reef fish trophic interactions.

PubMed

Miranda, Ricardo J; Nunes, José de Anchieta C C; Mariano-Neto, Eduardo; Sippo, James Z; Barros, Francisco

2018-07-01

Understanding how invasive species affect key ecological interactions and ecosystem processes is imperative for the management of invasions. We evaluated the effects of invasive corals (Tubastraea spp.) on fish trophic interactions in an Atlantic coral reef. Remote underwater video cameras were used to examine fish foraging activity (bite rates and food preferences) on invasive cover levels. Using a model selection approach, we found that fish feeding rates declined with increased invasive cover. For Roving Herbivores (RH) and Sessile Invertivores (SI), an abrupt reduction of fish feeding rates corresponded with higher invasive cover, while feeding rates of Territorial Herbivores (TH) and Mobile Invertivores (MI) decreased linearly with cover increase. Additionally, some fish trophic groups, such as RH, SI and Omnivores (OM), had lower densities in reef sections with high invasive cover. These findings demonstrate that invasive corals negatively impact fish-benthic interactions, and could potentially alter existing trophic relationships in reef ecosystems. Copyright © 2018 Elsevier Ltd. All rights reserved.

Modelling scenarios on feed-to-fillet transfer of dioxins and dioxin-like PCBs in future feeds to farmed Atlantic salmon (Salmo salar).

PubMed

Berntssen, Marc H G; Sanden, Monica; Hove, Helge; Lie, Øyvind

2016-11-01

The salmon feed composition has changed the last decade with a replacement of traditionally use of fish oil and fishmeal diets with vegetable ingredients and the use decontaminated fish oils, causing reduced concentrations of dioxins and dioxin-like PCBs in farmed Norwegian Atlantic salmon. The development of novel salmon feeds has prompted the need for prediction on dioxins and dl-PCB concentrations in future farmed salmon. Prediction on fillet dioxins and dl-PCB concentrations from different feed composition scenarios are made using a simple one-compartmental transfer model based on earlier established dioxin and dl-PCB congener specific uptake and elimination kinetics rates. The model is validated with two independent feeding trials, with a significant linear correlation (r(2) = 0.96, y = 1.0x, p < 0.0001, n = 116) between observed and predicted values. Model fillet predictions are made for the following four scenarios; (1) general feed composition of 1999, (2) feed composition of 2013, (3) future feed composition with high fish oil and meal replacement, (4) future feed composition with high fish oil and meal replacement and decontaminated fish oil. Model predictions of fillet dioxin and dl-PCB concentrations from 1999 (1.05 ng WHO2005-TEQs kg(-1)ww) and 2013 (0.57 ng WHO2005-TEQs kg(-1)ww) are in line with the data observed in national surveillance programs of those years (1.1 and 0.52 ng WHO2005-TEQs kg(-1)ww, respectively). Future use of high replacement and decontaminated oils feeds gave predicted fillet concentrations of 0.27 ng WHO2005-TEQs kg(-1)ww, which is near the limit of quantification. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fatty acid composition of fish species with different feeding habits from an Arctic Lake.

PubMed

Gladyshev, M I; Sushchik, N N; Glushchenko, L A; Zadelenov, V A; Rudchenko, A E; Dgebuadze, Y Y

2017-05-01

We compared the composition and content of fatty acids (FAs) in fish with different feeding habits (sardine (least) cisco Coregonus sardinella, goggle-eyed charr (pucheglazka) form of Salvelinus alpinus complex, humpback whitefish Coregonus pidschian, broad whitefish Coregonus nasus, boganid charr Salvelinus boganidae, and northern pike Esox lucius from an Arctic Lake. Feeding habits of the studied fish (planktivore, benthivore, or piscivore) significantly affected the composition of biomarker fatty acids and the ratio of stable isotopes of carbon and nitrogen in their biomass. The hypothesis on a higher content of eicosapentaenoic and docosahexaenoic acids in the fish of higher trophic level (piscivores) when compared within the same taxonomic group (order Salmoniformes) was confirmed.

Detection and recognition of uneaten fish food pellets in aquaculture using image processing

NASA Astrophysics Data System (ADS)

Liu, Huanyu; Xu, Lihong; Li, Dawei

2015-03-01

The waste of fish food has always been a serious problem in aquaculture. On one hand, the leftover fish food spawns a big waste in the aquaculture industry because fish food accounts for a large proportion of the investment. On the other hand, the left over fish food may pollute the water and make fishes sick. In general, the reason for fish food waste is that there is no feedback about the consumption of delivered fish food after feeding. So it is extremely difficult for fish farmers to determine the amount of feedstuff that should be delivered each time and the feeding intervals. In this paper, we propose an effective method using image processing techniques to solve this problem. During feeding events, we use an underwater camera with supplementary LED lights to obtain images of uneaten fish food pellets on the tank bottom. An algorithm is then developed to figure out the number of left pellets using adaptive Otsu thresholding and a linear-time component labeling algorithm. This proposed algorithm proves to be effective in handling the non-uniform lighting and very accurate number of pellets are counted in experiments.

Effects of hatchery rearing on Florida largemouth bass Micropterus floridanus resource allocation and performance under semi-natural conditions.

PubMed

Garlock, T M; Monk, C T; Lorenzen, K; Matthews, M D; St Mary, C M

2014-12-01

This study examined the growth, activity, metabolism and post-release survival of three groups of Florida largemouth bass Micropterus floridanus: wild-caught fish, hatchery fish reared according to standard practice (hatchery standard) and hatchery fish reared under reduced and unpredictable food provisioning (hatchery manipulated). Hatchery-standard fish differed from wild-caught fish in all measured variables, including survival in semi-natural ponds. Hatchery-standard and hatchery-manipulated fish showed higher activity levels, faster growth and lower standard metabolic rates than wild-caught fish in the hatchery. Fish reared under the manipulated feeding regime showed increased metabolic rates and increased post-release growth, similar to wild-caught fish. Their activity levels and post-release survival, however, remained similar to those of hatchery-standard fish. Activity was negatively correlated with post-release survival and failure of the feed manipulation to reduce activity may have contributed to its failure to improve post-release survival. Activity and post-release survival may be influenced by characteristics of the rearing environment other than the feeding regime, such as stock density or water flow rates. © 2014 The Fisheries Society of the British Isles.

Trophic niche of squids: Insights from isotopic data in marine systems worldwide

NASA Astrophysics Data System (ADS)

Navarro, Joan; Coll, Marta; Somes, Christoper J.; Olson, Robert J.

2013-10-01

Cephalopods are an important prey resource for fishes, seabirds, and marine mammals, and are also voracious predators on crustaceans, fishes, squid and zooplankton. Because of their high feeding rates and abundance, squids have the potential to exert control on the recruitment of commercially important fishes. In this review, we synthesize the available information for two intrinsic markers (δ15N and δ13C isotopic values) in squids for all oceans and several types of ecosystems to obtain a global view of the trophic niches of squids in marine ecosystems. In particular, we aimed to examine whether the trophic positions and trophic widths of squid species vary among oceans and ecosystem types. To correctly compare across systems, we adjusted squid δ15N values for the isotopic variability of phytoplankton at the base of the food web provided by an ocean circulation-biogeochemistry-isotope model. Studies that focused on the trophic ecology of squids using isotopic techniques were few, and most of the information on squids was from studies on their predators. Our results showed that squids occupy a large range of trophic positions and exploit a large range of trophic resources, reflecting the versatility of their feeding behavior and confirming conclusions from food-web models. Clear differences in both trophic position and trophic width were found among oceans and ecosystem types. The study also reinforces the importance of considering the natural variation in isotopic values when comparing the isotopic values of consumers inhabiting different ecosystems.

Peperomia pellucida leaf extract as immunostimulator in controlling motile aeromonad septicemia due to Aeromonas hydrophila in red hybrid tilapia, Oreochromis spp. farming

PubMed Central

Lee, S. W.; Sim, K. Y.; Wendy, W.; Zulhisyam, A. K.

2016-01-01

Aim: This study was revealed the potential of Peperomia pellucida leaf extract as an immunostimulator agent in controlling motile aeromonad septicemia due to Aeromonas hydrophila in red hybrid tilapia, Oreochromis sp. Materials and Methods: In the present study, minimum inhibitory concentration (MIC) of P. pellucida leaf extract against A. hydrophila was determined through two-fold microbroth dilution method. The plant extract was screening for its active compound using a gas chromatograph mass spectrometer, and the effectiveness of P. pellucida leaf extract as an immunostimulator agent was evaluated. The experimental fish were fed with medicated feed at three different concentrations (25 mg/kg, PP-25; 50 mg/kg, PP-50; and 100 mg/kg, PP-100) of P. pellucida leaf extract for 1 week before they were intraperitoneally exposed to A. hydrophila. Enzyme-linked immunosorbent assay was carried out to determine the value of antibody response to A. hydrophila in fish from a group of fish that received medicated feed, and the percentage of total cumulative mortality of the experimental fish were observed at the end of the experiment. Results: The results showed that the major bioactive compound is phytol (40%), and the MIC value was 31.5 mg/L. The value of antibody response to A. hydrophila in fish from a group of fish which received medicated feed (PP-25, 0.128±0.014 optical density [OD]; PP-50, 0.132±0.003 OD; and PP-100, 0.171±0.02 OD) was found significantly higher (p<0.05) compared to fish did not receive medicated feed (0.00 OD). Whereas, percentage cumulative mortality of fish from all groups of fish received medicated feed (PP-25, 18.0±3.2%; PP-50, 18.2±2.8%; and PP-100, 17.7±1.8%) were found significantly lower (p<0.05) compared to a group of fish did not receive medicated feed (83.2±1.4%). Conclusion: The findings of the present study indicated the huge potential of P. pellucida leaf extract as natural immunostimulator agent for aquaculture uses. PMID:27057104

Peperomia pellucida leaf extract as immunostimulator in controlling motile aeromonad septicemia due to Aeromonas hydrophila in red hybrid tilapia, Oreochromis spp. farming.

PubMed

Lee, S W; Sim, K Y; Wendy, W; Zulhisyam, A K

2016-03-01

This study was revealed the potential of Peperomia pellucida leaf extract as an immunostimulator agent in controlling motile aeromonad septicemia due to Aeromonas hydrophila in red hybrid tilapia, Oreochromis sp. In the present study, minimum inhibitory concentration (MIC) of P. pellucida leaf extract against A. hydrophila was determined through two-fold microbroth dilution method. The plant extract was screening for its active compound using a gas chromatograph mass spectrometer, and the effectiveness of P. pellucida leaf extract as an immunostimulator agent was evaluated. The experimental fish were fed with medicated feed at three different concentrations (25 mg/kg, PP-25; 50 mg/kg, PP-50; and 100 mg/kg, PP-100) of P. pellucida leaf extract for 1 week before they were intraperitoneally exposed to A. hydrophila. Enzyme-linked immunosorbent assay was carried out to determine the value of antibody response to A. hydrophila in fish from a group of fish that received medicated feed, and the percentage of total cumulative mortality of the experimental fish were observed at the end of the experiment. The results showed that the major bioactive compound is phytol (40%), and the MIC value was 31.5 mg/L. The value of antibody response to A. hydrophila in fish from a group of fish which received medicated feed (PP-25, 0.128±0.014 optical density [OD]; PP-50, 0.132±0.003 OD; and PP-100, 0.171±0.02 OD) was found significantly higher (p<0.05) compared to fish did not receive medicated feed (0.00 OD). Whereas, percentage cumulative mortality of fish from all groups of fish received medicated feed (PP-25, 18.0±3.2%; PP-50, 18.2±2.8%; and PP-100, 17.7±1.8%) were found significantly lower (p<0.05) compared to a group of fish did not receive medicated feed (83.2±1.4%). The findings of the present study indicated the huge potential of P. pellucida leaf extract as natural immunostimulator agent for aquaculture uses.

Sargassum horneri C. Agardh space capacity estimation reveals that thallus surface area varies with wet weight

PubMed Central

Sasa, Shuji; Komatsu, Teruhisa

2018-01-01

Sargassum horneri C. Agardh is an important commercial edible seaweed species in east Asia. Benthic beds and floating rafts in coastal areas make excellent habitats for marine organisms to feed, hide, and spawn. Many commercially important fish species such as Japanese anchovy (Engraulis japonicus), yellowtail (Seriola quinqueradiata), and Japanese horse mackerel (Trachurus japonicus) live in seaweed beds. Chinese and Japanese fisherman rely on S. horneri beds as productive fish harvest areas. The Zhejiang government in China set a total allowable catch standard, to preserve the Ma’an Islands ecosystem, which is a marine protected area. In this study we analysed the association between weight and one-sided surface area of S. horneri beds, and calculated the ratio of one-sided surface area to change in wet weight over time. We collected samples from December 2014 to May 2015. Approximately 1 g of S. horneri biomass provided ~15 cm2 of one-sided surface area available to marine organisms. These calculations can be used as a reference regarding potential space to improve total allowable catch standard management in S. horneri beds, through the estimation of space capacity of seaweed beds. PMID:29920534

Variability within nearshore ecosystems of the Gulf of Alaska

USGS Publications Warehouse

Ballachey, Brenda E.; Bodkin, James L.; Coletti, Heather A.; Dean, Thomas A; Esler, Daniel N.; Esslinger, George G.; Iken, Katrin; Kloecker, Kimberly A.; Konar, Brenda; Lindeberg, Mandy; Monson, Daniel; Shepherd, Marnie; Weitzman, Ben P.

2015-01-01

Nearshore marine habitats, which represent the interface among air, land and sea, form a critical component of the Gulf of Alaska (GOA) ecosystem. As an interface, the nearshore facilitates transfer of water, nutrients and biota between terrestrial and oceanic systems, creating zones of high productivity. The nearshore provides a variety of ecosystem services, including (1) nursery grounds for a wide variety of marine invertebrates and fishes (e.g., crabs, salmon, and herring), (2) nesting and pupping habitats for many pelagic marine predators (e.g., sea bird nesting colonies and pinniped rookeries), (3) important feeding habitats for high trophic level pelagic predators (e.g., killer whales), (4) habitat for resident nearshore species (including sea otters, harbor seals, shorebirds, sea ducks, nearshore fishes, and marine invertebrates), many of which are important sources of commercial and subsistence harvests, and (5) recreational, commercial and subsistence opportunities for human populations (Figure 1-1). The canopy forming kelps and eel grass beds found in the nearshore provide primary production and structure to nursery habitats, and also can dissipate wave energy thus reducing coastal erosion, and serve as a carbon “sink” capable of storing substantial amounts of atmospheric CO2 (Wilmers et al. 2012).

Spatial fishing restrictions benefit demersal stocks in the northeastern Mediterranean Sea.

PubMed

Dimarchopoulou, Donna; Dogrammatzi, Aikaterini; Karachle, Paraskevi K; Tsikliras, Athanassios C

2018-04-13

The multi-level benefits that marine organisms gain when protected from fishing are well acknowledged. Here, we investigated the effects of a 40-year trawling ban on the status of targeted and non-targeted marine species within a major fishing ground in the northeastern Mediterranean Sea (Thermaikos Gulf, Aegean Sea). Biomass and somatic length of fish and invertebrates (six commercial and three non-commercial demersal species) were measured in three areas of varying fishing pressure, depending on the temporal and spatial operational regimes of fishing vessels. The positive effects of fishing restrictions on the studied demersal stocks were clearly revealed, as the commercial fish species exhibited higher biomass in the intermediate and low pressure areas, as well as increasing maximum and mean total length (and other length indicators) with decreasing fishing effort. The mean total length of non-commercial species generally did not differ among areas, except for species caught and discarded at high rates. The present study shows that fishing does alter the population structure and biomass of commercial demersal species, and that fishing restrictions greatly contribute to improving the status of demersal populations within the restricted areas by providing a refuge for large individuals and their important contribution to the gene pool.

36 CFR 13.1144 - How often will commercial fishing lifetime access permit be renewed?

Code of Federal Regulations, 2013 CFR

2013-07-01

... NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Commercial Fishing § 13.1144 How often will commercial fishing... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false How often will commercial...

Sex reversal of brook trout (Salvelinus fontinalis) by 17α-methyltestosterone exposure: A serial experimental approach to determine optimal timing and delivery regimes.

PubMed

Fatima, Shafaq; Adams, Mark; Wilkinson, Ryan

2016-12-01

Commercial culture of Brook trout (Salvelinus fontinalis) in Tasmania was partly abandoned due to sexual maturation of male fish early on during the estuarine rearing phase. Maturation adversely affects body mass, flesh quality and immunocompetency effectively. Sex reversal techniques such as the in-feed addition of a synthetic androgen have proven difficult to adapt in brook trout. An appropriate timing, duration and delivery vehicle for administration of 17α-methyltestosterone (MT) to produce phenotypic males (neomales) from genotypically female brook trout required further investigation. In this study, groups of brook trout eggs (n=1000) maintained at 9.5±0.15-10±0.14°C, were immersed in MT (400μgL -1 ) for four hours on two alternate days (two immersions/group) staggered over a two week period surrounding the hatch of embryos (control groups excluded). The groups were then split and half received MT-supplemented feed for 60days and the other a standard diet. Following an 11 month on-growing period sex phenotypes were determined by gross & histological gonad morphology. The highest proportion of male phenotypes (75%) was found in fish immersed six and four days pre-hatch and subsequently fed a normal diet. Fish fed a MT supplemented diet and immersed in MT showed significantly higher proportions of sterile fish. These data indicate that a pre-hatch immersion-only regime (4-6days pre-hatch at 9.5°C) should be pursued as a target for optimization studies to further refine the effective concentration and duration of exposure to MT for the successful production of neo-male brook trout. Copyright © 2016 Elsevier B.V. All rights reserved.

Microbial and nutritional aspects on the production of live feeds in a fish farming industry.

PubMed

De Donno, A; Lugoli, F; Bagordo, F; Vilella, S; Campa, A; Grassi, T; Guido, M

2010-03-01

Aquaculture is an enterprise in constant development, in particular relating to its effect on the environment and also the quality of its products. It represents a valid alternative to traditional fishing, facing the increasing demand for fish products. To guarantee to the consumer a product of high nutritional, organoleptic and hygienic quality, it is fundamental to monitor every phase of the fish farming industry, isolating the potential risk points. For this reason there has been a rapid evolution of productive technique, particularly in the technology, artificial reproduction and feed sectors. The aim of this research has been the monitoring of the evolution of certain microbial and nutritional quality indexes (total microbial counts and lipid analysis on suspensions of Rotifers and Artemia, used as live feed) in the larval phase of the productive cycle of the farm raised fish, in an intensive system. The study has shown an increment in the total microbial counts in the fish farming industry within the production of Rotifers and Artemia, more evident in the suspensions of Rotifers. In addition the study has demonstrated that the maintenance phase, in the enrichment protocol, can reduce the EPA and DHA content. The results confirm the importance of microbial and nutritional control of the live feeds before they get supplied to fish larvae.

Feasibility of partial replacement of fishmeal with proteins from different sources in diets of Korean rockfish ( Sebastes schlegeli)

NASA Astrophysics Data System (ADS)

Yan, Quangen; Zhu, Xiaoming; Yang, Yunxia; Han, Dong; Xie, Shouqi

2014-12-01

An 8-week feeding experiment was conducted in an indoor recirculation seawater system to investigate the effects of partial replacement of dietary fishmeal with proteins from five sources on the growth performance and feed utilization of Sebastes schlegeli. Six isonitrogenous and isoenergetic diets were formulated using fishmeal (FM, the control) as sole protein source, or proteins from five sources including poultry by-product meal (PBM), meat and bone meal (MBM), soybean meal (SBM), cottonseed meal (CSM) and canola meal (CNM). Fifteen percent of the crude protein provided by fish meal was replaced, respectively. The results showed that the differences in specific growth rate (SGR) and survival rate (SR) among fish fed PBM, MBM, SBM, CSM and whole FM diets were not significant. However, SGR and SR of fish fed CNM diet was significantly lower than that of other treatments. Feeding rate, feed conversion, nutrient retention showed similar patterns to that of growth. Fish fed CSM and CNM showed significantly lower apparent digestibility coefficient (ADC) of dry matter and gross energy than those fed others while fish fed CNM showed lower ADC of crude protein than those fed others ( P<0.05). These results suggested that it was feasible to substitute 15% dietary protein provided by fishmeal with PBM, MBM, SBM and CSM, respectively, but not with CNM as the replacement with CNM reduced fish growth and feed utilization.

Effects of dietary soy isoflavones on feed intake, growth performance and digestibility in juvenile Japanese flounder ( Paralichthys olivaceus)

NASA Astrophysics Data System (ADS)

Mai, Kangsen; Zhang, Yanjiao; Chen, Wei; Xu, Wei; Ai, Qinghui; Zhang, Wenbing

2012-12-01

An 8-week feeding trial was conducted to investigate the effects of dietary soy isoflavones on feeding intake, growth performance, and digestion of juvenile Japanese flounder ( Paralichthys olivaceus). Four isonitrogenous (49% crude protein) and isoenergetic (20.1 MJ kg-1) diets were formulated to contain four graded levels of soy isoflavones, namely, 0, 1, 4 and 8 g soy isoflavones in 1 kg of diet. Each diet was randomly fed to triplicate tanks of fish (Initial average weight: 2.58 g ± 0.01 g), and each tank was stocked with 35 fish. No significant difference was observed among diets with levels of 0, 1 and 4 g kg-1 soy isoflavones in feed intake, weight gain, feed efficiency ratio (FER), proximate composition of fish whole body and apparent digestibility coefficients (ADC) of nutrients and energy ( P>0.05). However, high dietary soy isoflavones level (8 g kg-1) significantly depressed weight gain, FER, whole-body crude lipid content of fish and ADC of nutrients ( P<0.05). These results indicate that high level of dietary soy isoflavones (above 4 g kg-1) significantly depresses growth responses and FER of Japanese flounder. However, as the content of soy isoflavones in soybean meal is around 1 to 3 g kg-1, the adverse effects might be neglected when soybean products are used as a fish feed ingredient.

Energy density of lake whitefish Coregonus clupeaformis in Lakes Huron and Michigan

USGS Publications Warehouse

Pothoven, S.A.; Nalepa, T.F.; Madenjian, C.P.; Rediske, R.R.; Schneeberger, P.J.; He, J.X.

2006-01-01

We collected lake whitefish Coregonus clupeaformis off Alpena and Tawas City, Michigan, USA in Lake Huron and off Muskegon, Michigan USA in Lake Michigan during 2002–2004. We determined energy density and percent dry weight for lake whitefish from both lakes and lipid content for Lake Michigan fish. Energy density increased with increasing fish weight up to 800 g, and then remained relatively constant with further increases in fish weight. Energy density, adjusted for weight, was lower in Lake Huron than in Lake Michigan for both small (≤800 g) and large fish (>800 g). Energy density did not differ seasonally for small or large lake whitefish or between adult male and female fish. Energy density was strongly correlated with percent dry weight and percent lipid content. Based on data from commercially caught lake whitefish, body condition was lower in Lake Huron than Lake Michigan during 1981–2003, indicating that the dissimilarity in body condition between the lakes could be long standing. Energy density and lipid content in 2002–2004 in Lake Michigan were lower than data for comparable sized fish collected in 1969–1971. Differences in energy density between lakes were attributed to variation in diet and prey energy content as well as factors that affect feeding rates such as lake whitefish density and prey abundance.

Ocean Acidification Effects on Atlantic Cod Larval Survival and Recruitment to the Fished Population

PubMed Central

Stiasny, Martina H.; Mittermayer, Felix H.; Sswat, Michael; Voss, Rüdiger; Jutfelt, Fredrik; Chierici, Melissa; Puvanendran, Velmurugu; Mortensen, Atle; Reusch, Thorsten B. H.; Clemmesen, Catriona

2016-01-01

How fisheries will be impacted by climate change is far from understood. While some fish populations may be able to escape global warming via range shifts, they cannot escape ocean acidification (OA), an inevitable consequence of the dissolution of anthropogenic carbon dioxide (CO2) emissions in marine waters. How ocean acidification affects population dynamics of commercially important fish species is critical for adapting management practices of exploited fish populations. Ocean acidification has been shown to impair fish larvae’s sensory abilities, affect the morphology of otoliths, cause tissue damage and cause behavioural changes. Here, we obtain first experimental mortality estimates for Atlantic cod larvae under OA and incorporate these effects into recruitment models. End-of-century levels of ocean acidification (~1100 μatm according to the IPCC RCP 8.5) resulted in a doubling of daily mortality rates compared to present-day CO2 concentrations during the first 25 days post hatching (dph), a critical phase for population recruitment. These results were consistent under different feeding regimes, stocking densities and in two cod populations (Western Baltic and Barents Sea stock). When mortality data were included into Ricker-type stock-recruitment models, recruitment was reduced to an average of 8 and 24% of current recruitment for the two populations, respectively. Our results highlight the importance of including vulnerable early life stages when addressing effects of climate change on fish stocks. PMID:27551924

Ocean Acidification Effects on Atlantic Cod Larval Survival and Recruitment to the Fished Population.

PubMed

Stiasny, Martina H; Mittermayer, Felix H; Sswat, Michael; Voss, Rüdiger; Jutfelt, Fredrik; Chierici, Melissa; Puvanendran, Velmurugu; Mortensen, Atle; Reusch, Thorsten B H; Clemmesen, Catriona

2016-01-01

How fisheries will be impacted by climate change is far from understood. While some fish populations may be able to escape global warming via range shifts, they cannot escape ocean acidification (OA), an inevitable consequence of the dissolution of anthropogenic carbon dioxide (CO2) emissions in marine waters. How ocean acidification affects population dynamics of commercially important fish species is critical for adapting management practices of exploited fish populations. Ocean acidification has been shown to impair fish larvae's sensory abilities, affect the morphology of otoliths, cause tissue damage and cause behavioural changes. Here, we obtain first experimental mortality estimates for Atlantic cod larvae under OA and incorporate these effects into recruitment models. End-of-century levels of ocean acidification (~1100 μatm according to the IPCC RCP 8.5) resulted in a doubling of daily mortality rates compared to present-day CO2 concentrations during the first 25 days post hatching (dph), a critical phase for population recruitment. These results were consistent under different feeding regimes, stocking densities and in two cod populations (Western Baltic and Barents Sea stock). When mortality data were included into Ricker-type stock-recruitment models, recruitment was reduced to an average of 8 and 24% of current recruitment for the two populations, respectively. Our results highlight the importance of including vulnerable early life stages when addressing effects of climate change on fish stocks.

Local phylogenetic divergence and global evolutionary convergence of skull function in reef fishes of the family Labridae.

PubMed

Westneat, Mark W; Alfaro, Michael E; Wainwright, Peter C; Bellwood, David R; Grubich, Justin R; Fessler, Jennifer L; Clements, Kendall D; Smith, Lydia L

2005-05-22

The Labridae is one of the most structurally and functionally diversified fish families on coral and rocky reefs around the world, providing a compelling system for examination of evolutionary patterns of functional change. Labrid fishes have evolved a diverse array of skull forms for feeding on prey ranging from molluscs, crustaceans, plankton, detritus, algae, coral and other fishes. The species richness and diversity of feeding ecology in the Labridae make this group a marine analogue to the cichlid fishes. Despite the importance of labrids to coastal reef ecology, we lack evolutionary analysis of feeding biomechanics among labrids. Here, we combine a molecular phylogeny of the Labridae with the biomechanics of skull function to reveal a broad pattern of repeated convergence in labrid feeding systems. Mechanically fast jaw systems have evolved independently at least 14 times from ancestors with forceful jaws. A repeated phylogenetic pattern of functional divergence in local regions of the labrid tree produces an emergent family-wide pattern of global convergence in jaw function. Divergence of close relatives, convergence among higher clades and several unusual 'breakthroughs' in skull function characterize the evolution of functional complexity in one of the most diverse groups of reef fishes.

Dietary Prebiotics and Probiotics Influence the Growth Performance, Feed Utilisation, and Body Indices of Snakehead (Channa striata) Fingerlings

PubMed Central

Munir, Mohammad Bodrul; Hashim, Roshada; Abdul Manaf, Mohammad Suhaimee; Nor, Siti Azizah Mohd

2016-01-01

This study used a two-phase feeding trial to determine the influence of selected dietary prebiotics and probiotics on growth performance, feed utilisation, and morphological changes in snakehead (Channa striata) fingerlings as well as the duration of these effects over a post-experimental period without supplementation. Triplicate groups of fish (22.46 ±0.17 g) were raised on six different treatment diets: three prebiotics (0.2% β-glucan, 1% galacto-oligosaccharides [GOS], 0.5% mannan-oligosaccharides [MOS]), two probiotics (1% live yeast [Saccharomyces cerevisiae] and 0.01% Lactobacillus acidophilus [LBA] powder) and a control (unsupplemented) diet; there were three replicates for each treatment. All diets contained 40% crude protein and 12% crude lipid. Fish were fed to satiation three times daily. No mortalities were recorded during Phase 1; however, 14% mortality was documented in the control and prebiotic-amended fish during Phase 2. At the end of Phase 1, growth performance and feed utilisation were significantly higher (p<0.05) in the LBA-treated fish, followed by live yeast treatment, compared with all other diets tested. The performance of fish on the three prebiotic diets were not significantly different from one another but was significantly higher than the control diet. During Phase 2 (the post-feeding phase), fish growth continued until the 6th week for the probiotic-based diets but levelled off after four weeks for the fish fed the prebiotic diets. The feed conversion ratio (FCR) was higher in all treatments during the post-feeding period. The hepatosomatic index (HSI) did not differ significantly among the tested diets. The visceral somatic index (VSI) and intraperitoneal fat (IPF) were highest in the LBA-based diet and the control diet, respectively. The body indices were significantly different (p<0.05) between Phases 1 and 2. This study demonstrates that probiotic-based diets have a more positive influence on the growth, feed utilisation, and survival of C. striata fingerlings compared with supplementation with prebiotics. PMID:27688855

Intestinal microbiota composition is altered according to nutritional biorhythms in the leopard coral grouper (Plectropomus leopardus).

PubMed

Mekuchi, Miyuki; Asakura, Taiga; Sakata, Kenji; Yamaguchi, Tomofumi; Teruya, Kazuhisa; Kikuchi, Jun

2018-01-01

Aquaculture is currently a major source of fish and has the potential to become a major source of protein in the future. These demands require efficient aquaculture. The intestinal microbiota plays an integral role that benefits the host, providing nutrition and modulating the immune system. Although our understanding of microbiota in fish gut has increased, comprehensive studies examining fish microbiota and host metabolism remain limited. Here, we investigated the microbiota and host metabolism in the coral leopard grouper, which is traded in Asian markets as a superior fish and has begun to be produced via aquaculture. We initially examined the structural changes of the gut microbiota using next-generation sequencing and found that the composition of microbiota changed between fasting and feeding conditions. The dominant phyla were Proteobacteria in fasting and Firmicutes in feeding; interchanging the dominant bacteria required 12 hours. Moreover, microbiota diversity was higher under feeding conditions than under fasting conditions. Multivariate analysis revealed that Proteobacteria are the key bacteria in fasting and Firmicutes and Fusobacteria are the key bacteria in feeding. Subsequently, we estimated microbiota functional capacity. Microbiota functional structure was relatively stable throughout the experiment; however, individual function activity changed according to feeding conditions. Taken together, these findings indicate that the gut microbiota could be a key factor to understanding fish feeding conditions and play a role in interactions with host metabolism. In addition, the composition of microbiota in ambient seawater directly affects the fish; therefore, it is important to monitor the microbiota in rearing tanks and seawater circulating systems.

Mechanisms of drift-feeding behavior in juvenile Chinook salmon and the role of inedible debris in a clear water Alaskan stream

USGS Publications Warehouse

Neuswanger, Jason R.; Wipfli, Mark S.; Rosenberger, Amanda E.; Hughes, Nicholas F.

2014-01-01

Drift-feeding fish are challenged to discriminate between prey and similar-sized particles of debris, which are ubiquitous even in clear-water streams. Spending time and energy pursuing debris mistaken as prey could affect fish growth and the fitness potential of different foraging strategies. Our goal was to determine the extent to which debris influences drift-feeding fish in clear water under low-flow conditions when the distracting effect of debris should be at a minimum. We used high-definition video to measure the reactions of drift-feeding juvenile Chinook salmon (Oncorhynchus tshawytscha) to natural debris and prey in situ in the Chena River, Alaska. Among all potential food items fish pursued, 52 % were captured and quickly expelled from the mouth, 39 % were visually inspected but not captured, and only 9 % were ingested. Foraging attempt rate was only moderately correlated with ingestion rate (Kendall’s τ = 0.55), raising concerns about the common use of foraging attempts as a presumed index of foraging success. The total time fish spent handling debris increased linearly with foraging attempt rate and ranged between 4 and 25 % of total foraging time among observed groups. Our results help motivate a revised theoretical view of drift feeding that emphasizes prey detection and discrimination, incorporating ideas from signal detection theory and the study of visual attention in cognitive ecology. We discuss how these ideas could lead to better explanations and predictions of the spatial behavior, prey selection, and energy intake of drift-feeding fish.

Herbivory drives large-scale spatial variation in reef fish trophic interactions

PubMed Central

Longo, Guilherme O; Ferreira, Carlos Eduardo L; Floeter, Sergio R

2014-01-01

Trophic interactions play a critical role in the structure and function of ecosystems. Given the widespread loss of biodiversity due to anthropogenic activities, understanding how trophic interactions respond to natural gradients (e.g., abiotic conditions, species richness) through large-scale comparisons can provide a broader understanding of their importance in changing ecosystems and support informed conservation actions. We explored large-scale variation in reef fish trophic interactions, encompassing tropical and subtropical reefs with different abiotic conditions and trophic structure of reef fish community. Reef fish feeding pressure on the benthos was determined combining bite rates on the substrate and the individual biomass per unit of time and area, using video recordings in three sites between latitudes 17°S and 27°S on the Brazilian Coast. Total feeding pressure decreased 10-fold and the composition of functional groups and species shifted from the northern to the southernmost sites. Both patterns were driven by the decline in the feeding pressure of roving herbivores, particularly scrapers, while the feeding pressure of invertebrate feeders and omnivores remained similar. The differential contribution to the feeding pressure across trophic categories, with roving herbivores being more important in the northernmost and southeastern reefs, determined changes in the intensity and composition of fish feeding pressure on the benthos among sites. It also determined the distribution of trophic interactions across different trophic categories, altering the evenness of interactions. Feeding pressure was more evenly distributed at the southernmost than in the southeastern and northernmost sites, where it was dominated by few herbivores. Species and functional groups that performed higher feeding pressure than predicted by their biomass were identified as critical for their potential to remove benthic biomass. Fishing pressure unlikely drove the large-scale pattern; however, it affected the contribution of some groups on a local scale (e.g., large-bodied parrotfish) highlighting the need to incorporate critical functions into conservation strategies. PMID:25512851

Is feeding behaviour related to glass eel propensity to migrate?

NASA Astrophysics Data System (ADS)

Bureau du Colombier, Sarah; Lambert, Patrick; Bardonnet, Agnès

2008-11-01

Several studies have shown that eel diadromy is facultative and that migratory divergences may appear during glass eel estuarine migration. The origin of the differences in migratory behaviour among glass eels remains unclear but initial evidence supports the role of individual energetic and thyroidal status. Even if starvation is usually associated with glass eel migration, feeding does seem to occur in some glass eels. The aim of the present study was to investigate feeding behaviour and glass eel growth in relation to the propensity to migrate. Feeding rate and weight gain were higher in fish having a high propensity to migrate (M + fish) than in fish having a low propensity to migrate (M - fish) in fed glass eels, whereas no clear difference in the variation in body weight was observed among unfed fish (controls). M - fish initially had lower percent dry weight than M + fish, which suggests a link between appetite, propensity to migrate, and energy content. We discuss the role played by endocrine signals on these processes. In fish, thyroid hormones contribute to the control of growth and development. In addition, they play a role in flatfish and leptocephalus metamorphosis and appear to be involved in smolt and glass eel migratory behaviour. As such, they represent a good candidate which would promote the propensity to migrate as well as digestive system development. Their role in the hormonal control of food intake however remains vague. The large and sharp decline in glass eel abundances observed since the 1980s could partly be explained by changes in ocean productivity. If so, it could be accompanied by a decrease in glass eel energy stores. The ability to resume feeding in the course of the estuarine crossing would then represent a serious advantage to maintain energy levels compatible with migration.

Man induced change in community control in the north-western Black Sea: The top-down bottom-up balance.

PubMed

Bănaru, Daniela; Harmelin-Vivien, Mireille; Boudouresque, Charles F

2010-05-01

The present study shows how marine commercial fish food webs dramatically changed in the north-western Black Sea on both pelagic and benthic environments. Fisheries landings, diversity and equitability strongly decreased between 1965-1970 and 2001-2005. Fishes adapted their feeding behaviour to the increasingly low species diversity of the Black Sea communities. Their food web became poor and simplified following the loss of many top predator species and their trophic links. Linkage density, connectivity and Lyapunov stability proxy strongly decreased. The north-western Black Sea system switched from a complex top-down and bottom-up functioning pattern to a dominantly bottom-up functioning pattern. This study contributes to a better understanding of these transformations within the Danube-Black Sea system in the last decades. An attempt is made to relate these changes with river inputs, fisheries and coastal pollution. Copyright 2009 Elsevier Ltd. All rights reserved.

Population dynamics of the Laysan and other albatrosses in the North Pacific

USGS Publications Warehouse

Gould, Patrick J.; Hobbs, Rod; Ito, J.; Shaw, W.; Burgner, R.L.

1993-01-01

Laysan albatrosses (Diomedea immutabilis) are among the most prominent bird species which interact with commercial fisheries in the North Pacific. They are attracted to fishing nets and vessels and feed extensively on animals caught in nets, waste fish, offal, and refuse discarded from vessels. Approximately 17,500 individuals were killed in the five major high seas driftnet fisheries in 1990. Laysan albatross numbers are still increasing after being decimated in the early 1900's. Mortality in the high seas driftnet fisheries is reducing the recover rate by an estimated 0.4 to 1.6% per year depending on the intrinsic growth rate of the population. The impact of the fisheries is thought to be more severe on the less abundant black-footed albatross (Diomedea nigripes) which is also increasing but at a lower rate. No driftnet mortalities have been reported for the short-tailed albatross (Diomedea albatrus).

Evidence of a specialized feeding niche in a Late Triassic ray-finned fish: evolution of multidenticulate teeth and benthic scraping in †Hemicalypterus.

PubMed

Gibson, Sarah Z

2015-04-01

Fishes have evolved to exploit multiple ecological niches. Extant fishes in both marine (e.g., rabbitfishes, surgeonfishes) and freshwater systems (e.g., haplochromine cichlids, characiforms) have evolved specialized, scoop-like, multidenticulate teeth for benthic scraping, feeding primarily on algae. Here, I report evidence of the oldest example of specialized multidenticulate dentition in a ray-finned fish, †Hemicalypterus weiri, from the Upper Triassic Chinle Formation of southeastern Utah (∼210-205 Ma), USA. †H. weiri is a lower actinopterygian species that is phylogenetically remote from modern fishes, and has evolved specialized teeth that converge with those of several living teleost fishes (e.g., characiforms, cichlids, acanthurids, siganids), with a likely function of these teeth being to scrape algae off a rock substrate. This finding contradicts previously held notions that fishes with multicuspid, scoop-like dentition were restricted to teleosts, and indicates that ray-finned fishes were diversifying into different trophic niches and exploring different modes of feeding earlier in their history than previously thought, fundamentally altering our perceptions of the ecological roles of fishes during the Mesozoic.

36 CFR 13.1132 - What types of commercial fishing are authorized in Glacier Bay?

Code of Federal Regulations, 2010 CFR

2010-07-01

... NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Commercial Fishing § 13.1132 What types of commercial fishing are... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false What types of commercial...

36 CFR 13.1132 - What types of commercial fishing are authorized in Glacier Bay?

Code of Federal Regulations, 2013 CFR

2013-07-01

... NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Commercial Fishing § 13.1132 What types of commercial fishing are... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false What types of commercial...

Characterization of Satellite DNA Sequences from the Commercially Important Marine Rotifers Brachionus rotundiformis and Brachionus plicatilis.

PubMed

Boehm; Gibson; Lubzens

2000-01-01

This study was initiated to search for species-specific and strain-specific satellite DNA sequences for which oligonucleotide primers could be designed to differentiate between various commercially important strains of the marine monogonont rotifers Brachionus rotundiformis and Brachionus plicatilis. Two unrelated, highly reiterated satellite sequences were cloned and characterized. The eight sequenced monomers from B. rotundiformis and six from B. plicatilis had low intrarepeat variability and were similar in their overall lengths, A + T compositions, and high degrees of repeated motif substructure. However, hybridizations to 19 representative strains, sequence characterizations, and GenBank searches indicated that these two satellites are morphotype-specific and population-specific, respectively, and share little homology to each other or to other characterized sequences in the database. Primer pairs designed for the B. rotundiformis satellite confirmed hybridization specificities on polymerase chain reaction and could serve as a useful molecular diagnostic tool to identify strains belonging to the SS morphotype, which are gaining widespread usage as first feeds for marine fish in commercial production.

Transcriptomic and physiological responses to fishmeal substitution with plant proteins in formulated feed in farmed Atlantic salmon (Salmo salar)

PubMed Central

2012-01-01

Background Aquaculture of piscivorous fish is in continual expansion resulting in a global requirement to reduce the dependence on wild caught fish for generation of fishmeal and fish oil. Plant proteins represent a suitable protein alternative to fish meal and are increasingly being used in fish feed. In this study, we examined the transcriptional response of Atlantic salmon (Salmo salar) to a high marine protein (MP) or low fishmeal, higher plant protein replacement diet (PP), formulated to the same nutritional specification within previously determined acceptable maximum levels of individual plant feed materials. Results After 77 days of feeding the fish in both groups doubled in weight, however neither growth performance, feed efficiency, condition factor nor organ indices were significantly different. Assessment of histopathological changes in the heart, intestine or liver did not reveal any negative effects of the PP diet. Transcriptomic analysis was performed in mid intestine, liver and skeletal muscle, using an Atlantic salmon oligonucleotide microarray (Salar_2, Agilent 4x44K). The dietary comparison revealed large alteration in gene expression in all the tissues studied between fish on the two diets. Gene ontology analysis showed, in the mid intestine of fish fed PP, higher expression of genes involved in enteritis, protein and energy metabolism, mitochondrial activity/kinases and transport, and a lower expression of genes involved in cell proliferation and apoptosis compared to fish fed MP. The liver of fish fed PP showed a lower expression of immune response genes but a higher expression of cell proliferation and apoptosis processes that may lead to cell reorganization in this tissue. The skeletal muscle of fish fed PP vs MP was characterized by a suppression of processes including immune response, energy and protein metabolism, cell proliferation and apoptosis which may reflect a more energy efficient tissue. Conclusions The PP diet resulted in significant effects on transcription in all the 3 tissues studied. Despite of these alterations, we demonstrated that high level of plant derived proteins in a salmon diet allowed fish to grow with equal efficiency as those on a high marine protein diet, and with no difference in biometric quality parameters. PMID:22853566

Transcriptomic and physiological responses to fishmeal substitution with plant proteins in formulated feed in farmed Atlantic salmon (Salmo salar).

PubMed

Tacchi, Luca; Secombes, Christopher J; Bickerdike, Ralph; Adler, Michael A; Venegas, Claudia; Takle, Harald; Martin, Samuel A M

2012-08-01

Aquaculture of piscivorous fish is in continual expansion resulting in a global requirement to reduce the dependence on wild caught fish for generation of fishmeal and fish oil. Plant proteins represent a suitable protein alternative to fish meal and are increasingly being used in fish feed. In this study, we examined the transcriptional response of Atlantic salmon (Salmo salar) to a high marine protein (MP) or low fishmeal, higher plant protein replacement diet (PP), formulated to the same nutritional specification within previously determined acceptable maximum levels of individual plant feed materials. After 77 days of feeding the fish in both groups doubled in weight, however neither growth performance, feed efficiency, condition factor nor organ indices were significantly different. Assessment of histopathological changes in the heart, intestine or liver did not reveal any negative effects of the PP diet. Transcriptomic analysis was performed in mid intestine, liver and skeletal muscle, using an Atlantic salmon oligonucleotide microarray (Salar_2, Agilent 4x44K). The dietary comparison revealed large alteration in gene expression in all the tissues studied between fish on the two diets. Gene ontology analysis showed, in the mid intestine of fish fed PP, higher expression of genes involved in enteritis, protein and energy metabolism, mitochondrial activity/kinases and transport, and a lower expression of genes involved in cell proliferation and apoptosis compared to fish fed MP. The liver of fish fed PP showed a lower expression of immune response genes but a higher expression of cell proliferation and apoptosis processes that may lead to cell reorganization in this tissue. The skeletal muscle of fish fed PP vs MP was characterized by a suppression of processes including immune response, energy and protein metabolism, cell proliferation and apoptosis which may reflect a more energy efficient tissue. The PP diet resulted in significant effects on transcription in all the 3 tissues studied. Despite of these alterations, we demonstrated that high level of plant derived proteins in a salmon diet allowed fish to grow with equal efficiency as those on a high marine protein diet, and with no difference in biometric quality parameters.

78 FR 44958 - Commercial Fishing Safety Advisory Committee; Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-25

... be dedicated to continuing subcommittee sessions on training requirements and alternative safety... DEPARTMENT OF HOMELAND SECURITY Coast Guard [Docket No. USCG-2013-0625] Commercial Fishing Safety.... SUMMARY: The Commercial Fishing Safety Advisory Committee (CFSAC) will meet in Washington, DC to discuss...

50 CFR 300.22 - Eastern Pacific fisheries recordkeeping and written reports.

Code of Federal Regulations, 2011 CFR

2011-10-01

... fishing vessel or commercial passenger fishing vessel (CPFV) authorized to fish for tuna and tuna-like... relation to known physical features), and the tonnage of fish on board, by species. The record and bridge... resolutions of the IATTC, all commercial fishing vessels and CPFVs authorized to fish for tuna and tuna-like...

Application of co-anaerobic digester's effluent for sustainable agriculture and aquaculture in the Mekong Delta, Vietnam.

PubMed

Nguyen, V C N; Fricke, K

2015-01-01

This investigation studied the application of digester effluent from co-digestion of pig manure and spent mushroom substrate as a fertilizer for leaf mustard planting and as feed for Tilapia fish growing. The fish raising experiment was set up in 1 × 1 × 1 m hapa conditions (triplicate for each treatment) with the density of 10 individiual per hapa; the fish weight and length were measured every 10 days for 50 continuous days. The leaf mustard was planted in real conditions at farmer's garden with normal cultivation style, and the weight and length of the plant were measured four times during the growing period. The study result shows that the harvest yield of leaf mustard fertilized by the digester effluent was 5.4 times higher than that by an inorganic fertilizer (IF). In addition to its contribution to a higher yield, the digester effluent accelerated the flower formation and shortened cultivation duration. For Tilapia fish culture, the growing rate of fish in the treatments supplied with 50% digester effluent + 50% commercial food (CF) was not significantly different in comparison to the fish cultivation with 100% CF. The result strongly confirms that the digester effluent from a co-digestion biogas plant of pig dung and spent mushroom compost is possible to be used as an organic fertilizer well for not only vegetable planting but also fish culture.

Impact of carbon dioxide level, water velocity, and feeding regimen on growth and fillet attributes of cultured rainbow trout (Oncorhynchus mykiss)

USGS Publications Warehouse

Mazik, Patricia M.; Mazik, P.M.; Kenney, P.B.; Silverstein, J.T

2016-01-01

Production and management variables such as carbon dioxide (CO2) level, water velocity, and feeding frequency influence the growth and fillet attributes of rainbow trout (Oncorhynchus mykiss), as well as cost of production. More information is needed to determine the contributions of these variables to growth and fillet attributes to find the right balance between input costs and fish performance. Two studies, of 84 and 90 days duration, were conducted to determine the effects of CO2 level, water velocity, and feed frequency on rainbow trout growth, fillet yield, and fillet quality. In the first study, two CO2levels (30 and 49 mg/L) and two velocity levels (0.5 and 2.0 body lengths/s) were tested. In the second study two CO2 levels (30 and 49 mg/L) and two feeding regimens (fed once daily to satiation or three times daily to satiation) were tested. In the first study, after 84 days, fillet weight from high CO2 tanks was 13.5% lower than the fillet weights of fish from low CO2 tanks. Percent fat of fillets was higher in low CO2 fish (P = 0.05) after 84 days and, fish from the low CO2 treatment were larger (P < 0.01). Both studies had similar results in regards to fat content and weight of fillets in response to elevated CO2levels. Velocity had little affect on either whole wet weight or fillet attributes of rainbow trout in this study. Muscle tissue contained more (P < 0.01) fat when fish were fed three times daily (7.3%; day 90) compared to once daily (5.4%; day 90). Also, fish were larger (P < 0.05) when fed 3 times per day (1079 g; day 90) in comparison to only one daily feeding (792 g; day 90). Fish in high feed/high CO2 tanks were larger and had more fillet fat than fish from low feed/low CO2 tanks. To maximize rainbow trout growth at aquaculture facilities, management strategies should attempt to keep CO2 levels below 30 mg/L when cost efficient. However, feeding 2–3 times daily should reduce production losses if CO2 cannot be minimized. The effect of strain and velocity were minimal over the range we tested in comparison to the effects of CO2 and feeding regimen.

Light climate and dissolved organic carbon concentration influence species-specific changes in fish zooplanktivory

USGS Publications Warehouse

Weidel, Brian C.; Baglini, Katherine; Jones, Stuart E.; Kelly, Patrick T.; Solomon, Christopher T.; Zwart, Jacob A.

2017-01-01

Dissolved organic carbon (DOC) in lakes reduces light penetration and limits fish production in low nutrient lakes, reportedly via reduced primary and secondary production. Alternatively, DOC and light reductions could influence fish by altering their visual feeding. Previous studies report mixed effects of DOC on feeding rates of zooplanktivorous fish, but most investigators tested effects of a single concentration of DOC against clear-water, turbid, or algal treatments. We used a controlled laboratory study to quantify the effects of a DOC gradient (3–19 mg L−1) on average light climate and the zooplankton feeding rate of 3 common, north temperate fishes. Light availability, which was inversely related to DOC concentration, had a positive and linear effect on zooplankton consumption by juvenile largemouth bass (Micropterus salmoides) and bluegill (Lepomis macrochirus), explaining 22% and 28% of the variation in consumption, respectively. By contrast, zooplankton feeding rates by fathead minnow (Pimephales promelas) were best predicted by a nonlinear, negative influence of light (R2 = 0.13). In bluegill feeding trials we found a general trend for positive selection of larger zooplankton (Cladocera and Chaoboridae); however, the light climate did not influence the selection of prey type. Largemouth bass selected for larger-bodied zooplankton, with weak evidence that selectivity for large Cladocera changed from negative to neutral selection based on electivity values across the light gradient. Our results suggest that the effect of DOC on the light climate of lakes may directly influence fish zooplanktivory and that this influence may vary among fish species.

Behavioral responses of juvenile golden gray mullet Liza aurata to changes in coastal temperatures and consequences for benthic food resources

NASA Astrophysics Data System (ADS)

Como, S.; Lefrancois, C.; Maggi, E.; Antognarelli, F.; Dupuy, C.

2014-09-01

Temperature is an important factor for fish. Yet, little is known about temperature effects on the feeding behavior of fish and the subsequent consequences of these behavioral changes on the spatial distribution of resources. We analyzed the differences in the feeding behavior of two size classes of juvenile Liza aurata at two water temperatures (i.e. 10 °C and 20 °C), using laboratory mesocosms. We also examined whether potential temperature-induced changes in feeding behavior of the smaller size of L. aurata would affect the spatial distribution of the microphytobenthos (MPB) biomass, an important resource in coastal systems. Both the number of feeding events and the swimming velocity during feeding were higher at 20 °C than at 10 °C, independent of the fish size. The time spent feeding did not vary between 10 °C and 20 °C, while the distance covered during feeding was significantly smaller at 20 °C than at 10 °C. Grazing did not affect the mean MPB biomass, but did increase its spatial variance at the smaller scale (i.e. a few centimeters) at 20 °C. A high number of feeding events, a high swimming velocity during feeding and a small distance covered during feeding in 20 °C-acclimated L. aurata most likely represented an adaptation to an increase in metabolism, as well as to the need to reduce the energy costs of feeding at 20 °C. Results also indicated that changes in feeding behavior of the 20 °C-acclimated L. aurata were responsible for the increase in small-scale spatial variability in the MPB biomass but not an overall significant effect on the MPB mean. We suggested that the enhanced spatial patchiness due to grazing by fish at 20 °C might yield a local increase in the mean MPB biomass, probably increasing photosynthetic efficiency of cells and algal growth that counterbalance the negative effect of algal removal by fish.

Domestication affects exploratory behaviour of pikeperch (Sander lucioperca L.) during the transition to pelleted food.

PubMed

Molnár, Tamás; Csuvár, Adrienn; Benedek, Ildikó; Molnár, Marcell; Kabai, Péter

2018-01-01

Genetic selection for body size during domestication of animal species can inadvertently affect a number of physiological and behavioural traits. The pace-of-life syndrome (POLS) hypothesis predicts that domestication in an artificial environment lacking predators and providing abundant resources prefers proactive individuals with strong feeding motivation, high levels of aggression and risk taking, with low hypothalamus-pituitary-adrenal (HPA) axis responsiveness. In the present experiment we weaned fingerling pike-perch from live feed and habituated them to formulated feed. We recorded the number of weeks needed for the fish to accept pellets, their body length at the age of 100 days, their boldness in a novel object test and their HPI axis responsiveness. Individuals accepting the artificial feed within the first week grew larger than fish habituating later; therefore early weaners would be kept and bred in routine aquaculture procedures. Contrary to predictions of POLS hypothesis, fish weaning earlier and thus growing faster were less bold and had higher HPI axis responsiveness than fish accepting the pellets later or never. As live feed is preferred to artificial pellets, less competitive individuals may switch to pellets earlier. Inadvertent selection for stress sensitive fish may have an effect on production in aquaculture as well as on natural population after intensive restocking.

Domestication affects exploratory behaviour of pikeperch (Sander lucioperca L.) during the transition to pelleted food

PubMed Central

Csuvár, Adrienn; Benedek, Ildikó; Molnár, Marcell; Kabai, Péter

2018-01-01

Genetic selection for body size during domestication of animal species can inadvertently affect a number of physiological and behavioural traits. The pace-of-life syndrome (POLS) hypothesis predicts that domestication in an artificial environment lacking predators and providing abundant resources prefers proactive individuals with strong feeding motivation, high levels of aggression and risk taking, with low hypothalamus–pituitary–adrenal (HPA) axis responsiveness. In the present experiment we weaned fingerling pike-perch from live feed and habituated them to formulated feed. We recorded the number of weeks needed for the fish to accept pellets, their body length at the age of 100 days, their boldness in a novel object test and their HPI axis responsiveness. Individuals accepting the artificial feed within the first week grew larger than fish habituating later; therefore early weaners would be kept and bred in routine aquaculture procedures. Contrary to predictions of POLS hypothesis, fish weaning earlier and thus growing faster were less bold and had higher HPI axis responsiveness than fish accepting the pellets later or never. As live feed is preferred to artificial pellets, less competitive individuals may switch to pellets earlier. Inadvertent selection for stress sensitive fish may have an effect on production in aquaculture as well as on natural population after intensive restocking. PMID:29742135

50 CFR 300.211 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Management of Highly Migratory Fish Stocks in the Western and Central Pacific Ocean, with Annexes (WCPF... Conference on Highly Migratory Fish Stocks in the Western and Central Pacific Ocean, the terms used in this... information. Commercial, with respect to commercial fishing, means fishing in which the fish harvested, either...

50 CFR 300.211 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Management of Highly Migratory Fish Stocks in the Western and Central Pacific Ocean, with Annexes (WCPF... Conference on Highly Migratory Fish Stocks in the Western and Central Pacific Ocean, the terms used in this... information. Commercial, with respect to commercial fishing, means fishing in which the fish harvested, either...

25 CFR 241.3 - Commercial fishing, Annette Islands Reserve.

Code of Federal Regulations, 2010 CFR

2010-04-01

... salmon fishing at any four of the following sites in the Annette Islands Reserve, Alaska: (1) Annette... seconds west longitude. (c) Trap fishing season. Fishing for salmon with traps operated by the Metlakatla Indian Community is permitted only at such times as commercial salmon fishing with purse seines is...

25 CFR 241.3 - Commercial fishing, Annette Islands Reserve.

Code of Federal Regulations, 2011 CFR

2011-04-01

... salmon fishing at any four of the following sites in the Annette Islands Reserve, Alaska: (1) Annette... seconds west longitude. (c) Trap fishing season. Fishing for salmon with traps operated by the Metlakatla Indian Community is permitted only at such times as commercial salmon fishing with purse seines is...

Evolution of long-toothed fishes and the changing nature of fish-benthos interactions on coral reefs.

PubMed

Bellwood, David R; Hoey, Andrew S; Bellwood, Orpha; Goatley, Christopher H R

2014-01-01

Interactions between fishes and the benthos have shaped the development of marine ecosystems since at least the early Mesozoic. Here, using the morphology of fish teeth as an indicator of feeding abilities, we quantify changes over the last 240 million years of reef fish evolution. Fossil and extant coral reef fish assemblages reveal exceptional stasis in tooth design over time, with one notable exception, a distinct long-toothed form. Arising only in the last 40 million years, these long-toothed fishes have bypassed the invertebrate link in the food chain, feeding directly on benthic particulate material. With the appearance of elongated teeth, these specialized detritivores have moved from eating invertebrates to eating the food of invertebrates. Over evolutionary time, fishes have slid back down the food chain.

Spatial analysis of the trophic interactions between two juvenile fish species and their preys along a coastal-estuarine gradient

NASA Astrophysics Data System (ADS)

Kopp, Dorothée; Le Bris, Hervé; Grimaud, Lucille; Nérot, Caroline; Brind'Amour, Anik

2013-08-01

Coastal and estuarine systems provide nursery grounds for many marine fish species. Their productivity has been correlated with terrigeneous inputs entering the coastal-estuarine benthic food web, thereby favouring the establishment of fish juveniles. Studies in these ecosystems often describe the nursery as a single large habitat without verifying nor considering the presence of contiguous habitats. Our study aimed at identifying different habitats based on macrozoobenthic communities and morpho-sedimentary characteristics and assessing the trophic interactions between fish juveniles and their benthic preys within these habitats. It included 43 sampling sites covering 5 habitats in which we described taxonomically and quantitatively the invertebrates and fish communities with stable isotopes and gut contents. It suggested that the benthic common sole Solea solea displayed feeding plasticity at the population level, separating the juveniles (G0) from the older fish (G1) into different "feeding sub-populations". Size-based feeding plasticity was also observable in the spatial occupancy of that species in the studied bay. The demersal pouting, Trisopterus luscus, equally used the different habitats but displayed low feeding plasticity across and inside each habitat. Stable isotopes proved to be powerful tools to study the spatial distribution of trophic interactions in complex ecosystems like the bay of Vilaine and to define optimal habitats for fish that use the coastal-estuarine ecosystem as nursery grounds.

Alaska OCS socioeconomic studies program. Technical report number 30. Northern and western Gulf of Alaska petroleum development scenarios: commercial fishing industry analysis. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terry, J.M.; Gorham, A.H.; Larson, D.M.

1980-02-01

The objective of the report is to increase our understanding of the potential relationships between the commercial fishing and Outer Continental Shelf (OCS) petroleum industries and to project the potential impacts on the commercial fishing industry of the Gulf of Alaska that may occur as a result of the proposed OCS lease sales No. 46 and No. 55. To meet this objective, the report consists of: (1) the documentation and examination of the history and current trends of the Gulf of Alaska commercial fishing industry as necessary to develop a basis for projecting fishery development and potential interactions with themore » OCS petroleum industry, (2) the development of models used to forecast the level of commercial fishing industry activity through the year 2000 in the absence of OCS development pursuant to lease sales No. 46 and No. 55, and (3) an analysis of the potential impacts of lease sales No. 46 and No. 55 based on the hypothesized nature and magnitude of the activities of the commercial fishing and OCS petroleum industries. The study concentrates on the commercial fishing industry activities centered in Kodiak, Seward, Cordova, and Yakutat. Both the harvesting and processing sectors of the fishing industry are considered. The sources of impacts considered are the competition for labor, ocean space use, and the infrastructure.« less

Dietary Patterns during Complementary Feeding and Later Outcomes.

PubMed

Emmett, Pauline M

2016-01-01

Guidelines for healthy infant feeding provide advice on breastfeeding and complementary feeding. The Avon Longitudinal Study of Parents and Children (ALSPAC) derived dietary patterns in comparison to infant feeding guidelines and by using principal components analysis (PCA). The ALSPAC cohort was recruited during pregnancy. Parent-completed questionnaires assessed diet at age 6 and 15 months. Children were weighed and measured at 7 years of age and IQ was assessed at 8 years. A complementary feeding utility index was calculated in relation to 14 feeding recommendations. High scores on the index were due to longer breastfeeding, and feeding more fruit and vegetables and less ready-prepared baby foods. The index scores were positively related to IQ and 'healthy' dietary patterns in childhood. In infancy four dietary patterns were derived from PCA at each age. Three occurred at both ages: 'HM traditional' (home-made meat, vegetables and desserts), 'discretionary' (processed adult foods) and 'RM baby foods' (commercial ready-made baby foods). A 'breastfeeding' pattern was derived at 6 months, with fruit and vegetables included. At 15 months, a 'HM contemporary' pattern included cheese, fish, nuts, legumes, fruit and vegetables. The 'discretionary' and 'RM baby foods' patterns at both ages were negatively associated, while the 'breastfeeding' and 'HM contemporary' patterns were positively associated with IQ. These results suggest that infant diet influences cognitive development in children and may set a trend for later eating patterns. © 2016 Nestec Ltd., Vevey/S. Karger AG, Basel.

A dual pathways transfer model to account for changes in the radioactive caesium level in demersal and pelagic fish after the Fukushima Daï-ichi nuclear power plant accident

PubMed Central

Bailly-du-Bois, Pascal; Laguionie, Philippe; Morillon, Mehdi; Arnaud, Mireille; Cunin, Pascal

2017-01-01

The Fukushima Daï-ichi nuclear power plant (FDNPP) accident resulted in radioactive Cs being discharged into the local marine environment. While Cs bioaccumulates in biota and slowly depurates, the Cs concentrated in biota constitutes a source of Cs for animals feeding on each other. The marine biota therefore serves as a pool that recycles Cs, and this recycling process delays depuration in the fish feeding on this biota pool. Because the continental shelf is squeezed between the coast and very deep sea, the demersal marine species are confined to a narrow strip along the coast, close to the source of the radioactive input. Unlike demersal species, however, pelagic species are not restricted to the most contaminated area but instead spend some, if not most, of their time and feeding off-shore, far from the input source. We suggest that the feeding pathway for fish is a box whose size depends on their mobility, and that this feeding box is much larger and less contaminated (because of dilution through distance) for pelagic fish than for demersal fish. The aim of this paper is to test this hypothesis and to propose a simple operational model implementing two transfer routes: from seawater and from feeding. The model is then used to match the observational data in the aftermath of the FDNPP accident. PMID:28248982

Appearance traits in fish farming: progress from classical genetics to genomics, providing insight into current and potential genetic improvement

PubMed Central

Colihueque, Nelson; Araneda, Cristian

2014-01-01

Appearance traits in fish, those external body characteristics that influence consumer acceptance at point of sale, have come to the forefront of commercial fish farming, as culture profitability is closely linked to management of these traits. Appearance traits comprise mainly body shape and skin pigmentation. Analysis of the genetic basis of these traits in different fish reveals significant genetic variation within populations, indicating potential for their genetic improvement. Work into ascertaining the minor or major genes underlying appearance traits for commercial fish is emerging, with substantial progress in model fish in terms of identifying genes that control body shape and skin colors. In this review, we describe research progress to date, especially with regard to commercial fish, and discuss genomic findings in model fish in order to better address the genetic basis of the traits. Given that appearance traits are important in commercial fish, the genomic information related to this issue promises to accelerate the selection process in coming years. PMID:25140172

Amending reduced fish-meal feeds with marine lecithin, but not soy lecithin, improves the growth of juvenile cobia and may attenuate heightened responses to stress challenge.

PubMed

Trushenski, J; Schwarz, M; Pessoa, W V N; Mulligan, B; Crouse, C; Gause, B; Yamamoto, F; Delbos, B

2013-02-01

Sparing of marine resources in aquafeeds can be environmentally and economically advantageous; however, fish meal (FM) replacement can affect the production performance and physiological competence. Phospholipids are increasingly understood to be involved in maintaining growth and vigour in fish and may be deficient in reduced FM formulations. Accordingly, we evaluated the growth and stress tolerance of juvenile cobia fed typical (50% FM) or reduced FM feeds (12% FM) with or without phospholipid amendment [1% marine lecithin (12% FM + Marine PL) or soy lecithin (12% FM + Soy PL)] for 6 weeks in triplicate tanks (N = 3) in a recirculation aquaculture system. The 50% FM feed yielded significantly superior growth and growth efficiency in comparison with the 12% FM and 12% FM+ Soy PL feeds, but the 12% FM+ Marine PL feed yielded comparable results to 50% FM feed. A low-water stress challenge induced elevated plasma glucose, cortisol and lactate levels in all treatments. However, a significant interaction (diet × stress) effect suggested a lesser cortisol response among fish fed the 12% FM+ Marine PL and 50% FM diets. These findings demonstrate that growth performance and, perhaps, resilience of cobia raised on reduced FM feeds may be improved by the addition of marine-origin phospholipid to the diet. © 2011 Blackwell Verlag GmbH.

Automatic feeder for small fish held in tanks

USGS Publications Warehouse

Joeris, Leonard S.

1965-01-01

The Northville (Michigan) Biological Station has been a center for study of the developmental morphology of coregonid fishes. This work requires the production of numerous individual series of lake herring, lake whitefish, and several species of chubs from parent fish of positively known identity. The offspring of individual pairs or groups of fish must be held in individual tanks from the time they hatch until they reach maturity. One of the important problems in this project has been the poor growth of most fish. Though some have grown well, their growth has been less than that of the same species in nature, and a few fish from each hatch have grown very slowly. Irregularity of feeding may contribute to the slow growth of laboratory fish. The hatchery caretaker feeds them several times during his 8-hour workday, but they must go without food during the remaining 16 hours. The high metabolic rate of small fish, however, appears to make them strongly inclined toward almost continual feeding. Belief that greater, more regular food consumption would result from a mechanical feeder providing a continuous supply of food over a longer period of the day led to development of the equipment described in this paper.

Seasonal changes in community composition and trophic structure of fish populations of five salt marshes along the Essex coastline, United Kingdom

NASA Astrophysics Data System (ADS)

Green, Benjamin C.; Smith, David J.; Earley, Sarah E.; Hepburn, Leanne J.; Underwood, Graham J. C.

2009-11-01

European intertidal salt marshes are important nursery sites for juvenile fish and crustaceans. Due to the increasing threat of habitat loss, the seasonal changes of salt marsh fish communities need to be understood in order to appreciate the ecological and economic importance of the saltmarsh habitat. This study was the first in Great Britain to investigate the seasonal changes of salt marsh fish communities and the variation in community structure between closely located marsh habitats. Between February 2007 and March 2008, five marshes on three estuaries of the Essex coastline were sampled using flume nets to block off intertidal creeks at high tide. Fourteen fish species were caught. The community overall was dominated by three species that made up 91.6% of the total catch: the common goby Pomatoschistus microps (46.2% of the total catch), juvenile herring Clupea harengus (24.3%), and juvenile and larval sea bass Dicentrarchus labrax (21.2%). Cluster analysis demonstrated clear seasonal patterns, with some community structures unique to specific marshes or estuaries. The marsh fish community shifts from a highly diverse community during spring, to a community dominated by D. labrax and P. microps in autumn, and low diversity during winter months. Gravimetric stomach content analysis of fish community identified three main trophic guilds; macroinvertivores, planktivores and omnivores. The macroinvertivore feeding guild contained D. labrax and P. microps, the two most frequently occurring species. This investigation demonstrates the importance of British salt marshes as nursery habitats for commercial fish species.

Widespread kelp-derived carbon in pelagic and benthic nearshore fishes

USGS Publications Warehouse

von Biela, Vanessa R.; Newsome, Seth D.; Bodkin, James L.; Kruse, Gordon H.; Zimmerman, Christian E.

2016-01-01

Kelp forests provide habitat for diverse and abundant fish assemblages, but the extent to which kelp provides a source of energy to fish and other predators is unclear. To examine the use of kelp-derived energy by fishes we estimated the contribution of kelp- and phytoplankton-derived carbon using carbon (δ13C) and nitrogen (δ15N) isotopes measured in muscle tissue. Benthic-foraging kelp greenling (Hexagrammos decagrammus) and pelagic-foraging black rockfish (Sebastes melanops) were collected at eight sites spanning ∼35 to 60°N from the California Current (upwelling) to Alaska Coastal Current (downwelling) in the northeast Pacific Ocean. Muscle δ13C values were expected to be higher for fish tissue primarily derived from kelp, a benthic macroalgae, and lower for tissue primarily derived from phytoplankton, pelagic microalgae. Muscle δ13C values were higher in benthic-feeding kelp greenling than in pelagic-feeding black rockfish at seven of eight sites, indicating more kelp-derived carbon in greenling as expected. Estimates of kelp carbon contributions ranged from 36 to 89% in kelp greenling and 32 to 65% in black rockfish using carbon isotope mixing models. Isotopic evidence suggests that these two nearshore fishes routinely derive energy from kelp and phytoplankton, across coastal upwelling and downwelling systems. Thus, the foraging mode of nearshore predators has a small influence on their ultimate energy source as energy produced by benthic macroalgae and pelagic microalgae were incorporated in fish tissue regardless of feeding mode and suggest strong and widespread benthic-pelagic coupling. Widespread kelp contributions to benthic- and pelagic-feeding fishes suggests that kelp energy provides a benefit to nearshore fishes and highlights the potential for kelp and fish production to be linked.

Widespread kelp-derived carbon in pelagic and benthic nearshore fishes suggested by stable isotope analysis

NASA Astrophysics Data System (ADS)

von Biela, Vanessa R.; Newsome, Seth D.; Bodkin, James L.; Kruse, Gordon H.; Zimmerman, Christian E.

2016-11-01

Kelp forests provide habitat for diverse and abundant fish assemblages, but the extent to which kelp provides a source of energy to fish and other predators is unclear. To examine the use of kelp-derived energy by fishes we estimated the contribution of kelp- and phytoplankton-derived carbon using carbon (δ13C) and nitrogen (δ15N) isotopes measured in muscle tissue. Benthic-foraging kelp greenling (Hexagrammos decagrammus) and pelagic-foraging black rockfish (Sebastes melanops) were collected at eight sites spanning ∼35 to 60°N from the California Current (upwelling) to Alaska Coastal Current (downwelling) in the northeast Pacific Ocean. Muscle δ13C values were expected to be higher for fish tissue primarily derived from kelp, a benthic macroalgae, and lower for tissue primarily derived from phytoplankton, pelagic microalgae. Muscle δ13C values were higher in benthic-feeding kelp greenling than in pelagic-feeding black rockfish at seven of eight sites, indicating more kelp-derived carbon in greenling as expected. Estimates of kelp carbon contributions ranged from 36 to 89% in kelp greenling and 32 to 65% in black rockfish using carbon isotope mixing models. Isotopic evidence suggests that these two nearshore fishes routinely derive energy from kelp and phytoplankton, across coastal upwelling and downwelling systems. Thus, the foraging mode of nearshore predators has a small influence on their ultimate energy source as energy produced by benthic macroalgae and pelagic microalgae were incorporated in fish tissue regardless of feeding mode and suggest strong and widespread benthic-pelagic coupling. Widespread kelp contributions to benthic- and pelagic-feeding fishes suggests that kelp energy provides a benefit to nearshore fishes and highlights the potential for kelp and fish production to be linked.

Fermentation of non-sterilized fish biomass with a mixed culture of film-forming yeasts and lactobacilli and its effect on innate and adaptive immunity in mice.

PubMed

Inoue, Shigeaki; Suzuki-Utsunomiya, Kyoko; Komori, Yukako; Kamijo, Akemi; Yumura, Isao; Tanabe, Koudai; Miyawaki, Ayumi; Koga, Kunimasa

2013-12-01

Non-sterilized fish waste containing fish bones was fermented using combined starter cultures of film-forming yeast (Candida ethanolica) and lactic acid bacteria (LAB; Lactobacillus casei and Lactobacillus rhamnosus) in order to obtain a liquefied fermented broth without spoiling. During the entire fermentation, the number of LAB cells was maintained at a high level (6 × 10(8)-5 × 10(7) cells/ml). Although the number of general bacteria was 10(6)cell/ml after adding non-sterilized fish biomass, its growth was suppressed to be 1-3 × 10(4) cells/ml. The entire biomass had completely liquefied and the fermented broth contained all 20 α-amino acids composed of protein and also various kinds of minerals in abundance. The weight of mice group fed the fermented broth content feed (sample feed) for 31 days significantly increased compared with that fed no broth feed (control feed) (21.37 g vs 20.76 g (p < 0.05). No abnormal behavior and appearance were observed. All internal organs (the heart, the liver, the lung, the intestines, and the spleen) of both groups were confirmed to be normal by visual observation. In peripheral blood, the percentages of NK cells and CD8+ T cells of the mice in the sample feed group increased significantly relative to those in the control feed group (NK cells: 19% vs 11%, CD8+ T cells: 9% vs 5%, p < 0.05). In the spleen, the percentage of NK cells in the sample feed group also increased significantly compared to that in the control feed group (p < 0.05). The fermented fish biomass is expected to be effective for innate and adaptive immunity and thus fit for animal feed. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Effect of β-1, 3 glucan binding protein based zinc oxide nanoparticles supplemented diet on immune response and disease resistance in Oreochromis mossambicus against Aeromonas hydrophila.

PubMed

Anjugam, Mahalingam; Vaseeharan, Baskaralingam; Iswarya, Arokiadhas; Gobi, Narayanan; Divya, Mani; Thangaraj, Merlin P; Elumalai, Preetham

2018-05-01

Recently, several immunostimulants such as β-glucan, microbial and plant products have been used as dietary supplements to combat disease outbreaks in aquaculture. The present study investigates the potential of Portunus pelagicus β-1, 3 glucan binding protein based zinc oxide nanoparticles (Ppβ-GBP-ZnO NPs) supplemented diet on growth, immune response and disease resistance in Mozambique tilapia, Oreochromis mossambicus. The immune-related protein β-GBP was purified from the haemolymph of P. pelagicus using Sephadex G-100 affinity column chromatography. Ppβ-GBP-ZnO NPs was physico- chemically characterized and experimental feed was formulated. Fish were separately fed with commercial diet (control-group I) and Ppβ-GBP (group II, III, IV), Ppβ-GBP-ZnO NPs (group V, VI, VII), chem-ZnO NPs (VIII, IX, X) mixed diet at the concentration of 0.001%, 0.002% and 0.004% respectively. Triplicate groups of O. mossambicus were fed with experimental diets twice a day for 30 days. Fish receiving Ppβ-GBP-ZnO NPs supplemented diet showed a significant increase (P < 0.05) in growth performance. Cellular immune responses (myeloperoxidase activity, lysozyme activity and reactive oxygen species activity) and humoral immune responses (complement activity, antiprotease activity and alkaline phosphatase activity) were evaluated at an interval of 15 days during the feeding trial. Results demonstrate that both cellular and humoral immune responses were substantially increased (P < 0.05) in fish fed with 0.004% of Ppβ-GBP-ZnO NPs supplemented diet than others. Antibiofilm potential of Ppβ-GBP-ZnO NPs against Aeromonas hydrophila was visualized through confocal laser scanning microscopy (CLSM), which reveals reduction in the preformed biofilm thickness to 10 μm  at the concentration of 50 μg/ml. Furthermore, after 30 days of feeding trial, fish were challenged with aquatic fish pathogen A. hydrophila (1 × 10 7  cells ml -1 ) through intraperitoneal injection. Challenge study displayed a reduced mortality rate in fish fed with diet containing Ppβ-GBP-ZnO NPs. Thus our study suggests that dietary supplementation of Ppβ-GBP-ZnO NPs at 0.004% may have a potential effect to enhance the immune system and survival of O. mossambicus. Copyright © 2018 Elsevier Ltd. All rights reserved.

Local phylogenetic divergence and global evolutionary convergence of skull function in reef fishes of the family Labridae

PubMed Central

Westneat, Mark W; Alfaro, Michael E; Wainwright, Peter C; Bellwood, David R; Grubich, Justin R; Fessler, Jennifer L; Clements, Kendall D; Smith, Lydia L

2005-01-01

The Labridae is one of the most structurally and functionally diversified fish families on coral and rocky reefs around the world, providing a compelling system for examination of evolutionary patterns of functional change. Labrid fishes have evolved a diverse array of skull forms for feeding on prey ranging from molluscs, crustaceans, plankton, detritus, algae, coral and other fishes. The species richness and diversity of feeding ecology in the Labridae make this group a marine analogue to the cichlid fishes. Despite the importance of labrids to coastal reef ecology, we lack evolutionary analysis of feeding biomechanics among labrids. Here, we combine a molecular phylogeny of the Labridae with the biomechanics of skull function to reveal a broad pattern of repeated convergence in labrid feeding systems. Mechanically fast jaw systems have evolved independently at least 14 times from ancestors with forceful jaws. A repeated phylogenetic pattern of functional divergence in local regions of the labrid tree produces an emergent family-wide pattern of global convergence in jaw function. Divergence of close relatives, convergence among higher clades and several unusual ‘breakthroughs’ in skull function characterize the evolution of functional complexity in one of the most diverse groups of reef fishes. PMID:16024356

Predation scars may influence host susceptibility to pathogens: evaluating the role of corallivores as vectors of coral disease.

PubMed

Nicolet, K J; Chong-Seng, K M; Pratchett, M S; Willis, B L; Hoogenboom, M O

2018-03-27

Infectious diseases not regulated by host density, such as vector-borne diseases, have the potential to drive population declines and extinctions. Here we test the vector potential of the snail Drupella sp. and butterflyfish Chaetodon plebeius for two coral diseases, black band (BBD) and brown band (BrB) disease. Drupella transmitted BrB to healthy corals in 40% of cases immediately following feeding on infected corals, and even in 12% of cases 12 and 24 hours following feeding. However, Drupella was unable to transmit BBD in either transmission treatment. In a field experiment testing the vector potential of naturally-occurring fish assemblages, equivalent numbers of caged and uncaged coral fragments became infected with either BrB, BBD or skeletal eroding band, indicating that corallivorous fish were unlikely to have caused transmission. In aquaria, C. plebeius did not transmit either BBD or BrB, even following extended feeding on both infected and healthy nubbins. A literature review confirmed only four known coral disease vectors, all invertebrates, corroborating our conclusion that polyp-feeding fishes are unlikely to be vectors of coral diseases. This potentially because polyp-feeding fishes produce shallow lesions, not allowing pathogens to invade coral tissues. In contrast, corallivorous invertebrates that create deeper feeding scars increase pathogens transmission.

Why are prices in wild catch and aquaculture industries so different?

PubMed

Villasante, Sebastián; Rodríguez-González, David; Antelo, Manel; Rivero-Rodríguez, Susana; Lebrancón-Nieto, Joseba

2013-12-01

Through a comparative analysis of prices in capture fisheries and aquaculture sectors, the objectives of this paper are a) to investigate three the trends in prices of forage catches to feed the aquaculture species, b) to analyze the amount of fish species need to feed aquaculture species in order to assess the level of efficiency in resource use, and c) to examine the degree of economic concentration either in wild-catch industry and aquaculture sectors. The results show that prices of cultivated species are higher than prices of the same species when harvested from the sea. We explain this fact by the interplay of three forces. First, the amount of wild fish to feed aquaculture species continues to improve over time. Second, the pressure of fishing activities has not been reduced since catches of most forage fishes are declining, which induce higher prices of capture species that feed aquaculture production. Third, the level of seafood market concentration is significantly higher in aquaculture than in wild catches, which generates higher prices in aquaculture.

Dietary Supplementation with Allspice Pimenta dioica Reduces the Occurrence of Streptococcal Disease during First Feeding of Mozambique Tilapia Fry.

PubMed

Yılmaz, Sevdan; Ergün, Sebahattin

2014-09-01

Abstract Allspice Pimenta dioica as a feed additive was studied for its effects on growth performance and disease resistance in Mozambique Tilapia Oreochromis mossambicus. Five isonitrogenous (36% crude protein) and isocaloric (18.5 kJ/g) diets were formulated to contain 0 (control), 5, 10, 15, or 20 g of allspice/kg of fish feed. In a 50-d feeding trial, 15 plastic tanks (21 L) were stocked with 35 fish fry (0.012 g) each. After the feeding trial, fish were exposed to Streptococcus iniae and mortalities were recorded. The second-order polynomial regression indicated that the dietary allspice level of 10 g/kg provided the best growth performance and feed utilization. The greatest survival after pathogen challenge was also obtained from the diet supplemented with allspice at 10 g/kg. Therefore, allspice acts as a growth promoter to improve feed utilization and weight gain in Mozambique Tilapia fry and acts an antimicrobial agent to enhance disease resistance during first feeding of fry. These results suggest that allspice can be used as an alternative to antibiotics in controlling streptococcal disease in tilapia culture. Received October 19, 2012; accepted January 20, 2014.

Nutritional mitigation of winter thermal stress in gilthead seabream: Associated metabolic pathways and potential indicators of nutritional state.

PubMed

Richard, Nadège; Silva, Tomé S; Wulff, Tune; Schrama, Denise; Dias, Jorge P; Rodrigues, Pedro M L; Conceição, Luís E C

2016-06-16

A trial was carried out with gilthead seabream juveniles, aiming to investigate the ability of an enhanced dietary formulation (diet Winter Feed, WF, containing a higher proportion of marine-derived protein sources and supplemented in phospholipids, vitamin C, vitamin E and taurine) to assist fish in coping with winter thermal stress, compared to a low-cost commercial diet (diet CTRL). In order to identify the metabolic pathways affected by WF diet, a comparative two dimensional differential in-gel electrophoresis (2D-DIGE) analysis of fish liver proteome (pH 4–7) was undertaken at the end of winter. A total of 404 protein spots, out of 1637 detected, were differentially expressed between the two groups of fish. Mass spectrometry analysis of selected spots suggested that WF diet improved oxidative stress defense, reduced endoplasmic reticulum stress, enhanced metabolic flux through methionine cycle and phenylalanine/tyrosine catabolism, and induced higher aerobic metabolism and gluconeogenesis. Results support the notion that WF diet had a positive effect on fish nutritional state by partially counteracting the effect of thermal stress and underlined the sensitivity of proteome data for nutritional and metabolic profiling purposes. Intragroup variability and co-measured information were also used to pinpoint which proteins displayed a stronger relation with fish nutritional state. Winter low water temperature is a critical factor for gilthead seabream farming in the Mediterranean region, leading to a reduction of feed intake, which often results in metabolic and immunological disorders and stagnation of growth performances. In a recent trial, we investigated the ability of an enhanced dietary formulation (diet WF) to assist gilthead seabream in coping with winter thermal stress, compared to a standard commercial diet (diet CTRL). Within this context, in the present work, we identified metabolic processes that are involved in the stress-mitigating effect observed with diet WF, by undertaking a comparative analysis of fish liver proteome at the end of winter. This study brings information relative to biological processes that are involved in gilthead seabream winter thermal stress and shows that these can be mitigated through a nutritional strategy, assisting gilthead seabream to deal better with winter thermal conditions. Furthermore, the results show that proteomic information not only clearly distinguishes the two dietary groups from each other, but also captures heterogeneities that reflect intra-group differences in nutritional state. This was exploited in this work to refine the variable selection strategy so that protein spots displaying a stronger correlation with “nutritional state” could be identified as possible indicators of gilthead seabream metabolic and nutritional state. Finally, this study shows that gel-based proteomics seems to provide more reliable information than transmissive FT-IR spectroscopy, for the purposes of nutritional and metabolic profiling.

Long-term dietary replacement of fishmeal and fish oil in diets for rainbow trout (Oncorhynchus mykiss): Effects on growth, whole body fatty acids and intestinal and hepatic gene expression

PubMed Central

Lazzarotto, Viviana; Larroquet, Laurence; Corraze, Geneviève

2018-01-01

The effects of replacing fishmeal and fish oil with a plant-based diet were studied in juvenile (10g) and ongrowing (250-350g) rainbow trout from first-feeding. Feed-related differences in the intestinal and hepatic transcriptome were examined in juveniles after 7 months of feeding at 7°C. Based on microarray results obtained for juveniles, the expression of selected genes related to lipid, cholesterol and energy metabolisms, was assessed by RT-qPCR in ongrowing trout after 6 additional months of feeding at 17°C. Plasma glucose and cholesterol, lipid content and fatty acid profile of whole body were analyzed at both stages. After 7 months at 7°C, all juveniles reached the same body weight (10g), while at 13 months ongrowing fish fed the totally plant-based diet exhibited lower body weight (234 vs 330-337g). Body lipid content was higher in juveniles fed the totally plant-based diet (13.2 vs 9.4–9.9%), and plasma cholesterol was about 2-times lower in trout fed the plant-based diets at both stages. Fatty acid profile mirrored that of the respective diet, with low proportions of long-chain n-3 polyunsaturated fatty acids in fish fed plant-based diets. Genes involved in protein catabolism, carbohydrate metabolism and trafficking were down-regulated in the intestines of juveniles fed the plant-based diets. This was not true for ongrowing fish. Genes involved in lipid and cholesterol metabolisms were up-regulated in the livers of fish fed plant-based diets for both stages. In this study, feeding trout a totally plant-based diet from first-feeding affect a relatively low proportion of metabolism-related genes. In the longer term, when fish were reared at a higher temperature, only some of these changes were maintained (i.e. up-regulation of lipid/cholesterol metabolism). Although the plant-based diets tested in this study had no major deficiencies, small adjustments in the feed-formula are needed to further optimize growth performance while sparing marine resources. PMID:29364933

Vaccines for fish in aquaculture.

PubMed

Sommerset, Ingunn; Krossøy, Bjørn; Biering, Eirik; Frost, Petter

2005-02-01

Vaccination plays an important role in large-scale commercial fish farming and has been a key reason for the success of salmon cultivation. In addition to salmon and trout, commercial vaccines are available for channel catfish, European seabass and seabream, Japanese amberjack and yellowtail, tilapia and Atlantic cod. In general, empirically developed vaccines based on inactivated bacterial pathogens have proven to be very efficacious in fish. Fewer commercially available viral vaccines and no parasite vaccines exist. Substantial efficacy data are available for new fish vaccines and advanced technology has been implemented. However, before such vaccines can be successfully commercialized, several hurdles have to be overcome regarding the production of cheap but effective antigens and adjuvants, while bearing in mind environmental and associated regulatory concerns (e.g., those that limit the use of live vaccines). Pharmaceutical companies have performed a considerable amount of research on fish vaccines, however, limited information is available in scientific publications. In addition, salmonids dominate both the literature and commercial focus, despite their relatively small contribution to the total volume of farmed fish in the world. This review provides an overview of the fish vaccines that are currently commercially available and some viewpoints on how the field is likely to evolve in the near future.

Utilization of dipeptide/protein based diets in larval and juvenile Koi carp--post-prandial free amino acid levels.

PubMed

Kwasek, K; Zhang, Y; Dabrowski, K

2010-02-01

We have shown previously that diets in which the nitrogen portion is based on synthetic dipeptides (PP) resulted in weight gain by rainbow trout alevins when free amino acid (FAA) based diets did not. However, the protein-based diet used as a control in the previous study resulted in a significantly better performance of fish than peptide- or FAA based diet fed fish. Therefore, the objectives of our study were (i) to test how stomachless fish respond to peptide-based diets, (ii) to evaluate PP and protein-PP mixture diets and (iii) to examine if post-prandial response to FAA concentrations in the fish body can be used as an indicator of the availability of dietary amino acid sources. The first experiment was conducted with a 4-day old Koi carp (Cyprinus carpio) larvae and included groups fed a casein-gelatin (CG) based diet, a commercial diet and live Artemia nauplii. In the second experiment, fish fed live Artemia for 3 weeks (69 +/- 12 mg) were placed in glass aquaria in triplicate per dietary treatment. Four diets provided equivalent amounts of nitrogen in the form of a CG, a PP, a 50% PP and 50% CG (PP50) mix and as FAA. Fish were fed at 1 and 3 h intervals, and the survival and growth were monitored during the second and third weeks of experiments 1 and 2 respectively. Following the completion of feeding, juvenile carp were sampled prior to feeding and 3 h after a meal. Whole body FAA analyses were carried out. We observed marginal suitability of the CG diet for larval Koi carp, as earlier indicated in common carp. Juvenile Koi carp fed the CG diet achieved 236 +/- 19 mg, whereas PP50, PP and FAA diet fed fish grew to 140 +/- 37, 70 +/- 8 and 73 +/- 5 mg respectively. Free amino acids in the fish body, and in particular indispensable amino acids (IDAA), were excellent indicators of dietary availability. The present experiment shows that a dietary 1:1 ratio of protein to synthetic PPs results in better growth, survival and whole body IDAA concentrations in relation to FAA- and PP-based diets confirming earlier reports on the use of synthetic PP-based diets, although this diet does not match the performance of complete protein, CG-based diet.

Effect of nitrogen and fish manure fertilization on growth and chemical composition of lettuce

NASA Astrophysics Data System (ADS)

Yildirim, Ertan; Kul, Raziye; Turan, Metin; Ekinci, Melek; Alak, Gonca; Atamanalp, Muhammet

2016-04-01

Present experiment was designed to determine the response of various dozes of fish manure (FM) and commercial fertilizers on plant growth, yield and nutrient content of lettuce. The treatments consisted of fish manure, commercial fertilizer and the combination of fish manure and commercial fertilizer with four dozes of nitrogen (0 kg/ha, 100 kg/ha, 150 kg/ha and 200 kg/ha). The results of the study showed that treatments significantly affected the growth and chemical characteristics of lettuce. The best results in regard to plant growth and yield were obtained from 100 and 150 kg kg/ha nitrogen dozes of the combination of fish manure and commercial fertilizer.

Use of fish corrals in the seine fishery of the Virgin Islands

USGS Publications Warehouse

Jennings, C.A.

1990-01-01

Although selected aspects of the commercial fishery in the Virgin Islands have been documented since the early 1930's, fish corrals and their use have not been described. This account, based on personal observations made during 1985-86, summarizes commercial fishing methods in the Virgin Islands (U.S. and British), documents the use of fish corrals, and serves as an introduction to the methodologies of this harvesting technique. Interviews of commercial fishermen about how and when fish corrals are used provided information not available from direct observation.

Development of farmed fish: a nutritionally necessary alternative to meat.

PubMed

Sargent, J R; Tacon, A G

1999-05-01

The projected stagnation in the catch from global fisheries and the continuing expansion of aquaculture is considered against the background that fishmeal and fish oil are major feed stocks for farmed salmon and trout, and also for marine fish. The dietary requirement of these farmed fish for high-quality protein, rich in essential amino acids, can be met by sources other than fishmeal. However, the highly-polyunsaturated fatty acids eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3) present in high concentrations in fish oil are essential dietary constituents for marine fish and highly-desirable dietary constituents for salmonids. Currently, there is no feasible alternative source to fish oil for these nutrients in fish feeds. Vegetable oils rich in linoleic acid (18:2n-6) can partially substitute for 20:5n-3 and 22:6n-3 in salmonid and marine-fish feeds. However, this is nutritionally undesirable for human nutrition because the health-promoting effects of fish-derived 20:5n-3 and 22:6n-3 reflect a very high intake of 18:2n-6 relative to linolenic acid (18:3n-3) in Western diets. If partial replacement of fish oils in fish feeds with vegetable oils becomes necessary in future, it is argued that 18:3n-3-rich oils, such as linseed oil, are the oils of choice because they are much more acceptable from a human nutritional perspective, especially given the innate ability of freshwater fish, including salmonids, to convert dietary 18:3n-3 to 20:5n-3 and 22:6n-3. In the meantime, a more judicious use of increasingly-expensive fish oil in aquaculture is recommended. High priorities in the future development of aquaculture are considered to be genetic improvement of farmed fish stocks with enhanced abilities to convert C18 to C20 and C22 n-3 polyunsaturated fatty acids, enhanced development of primary production of 20:5n-3 and 22:6n-3 by single-cell marine organisms, and continuing development of new species.

Time trend investigation of PCBs, PBDEs, and organochlorine pesticides in selected n-3 polyunsaturated fatty acid rich dietary fish oil and vegetable oil supplements; nutritional relevance for human essential n-3 fatty acid requirements.

PubMed

Jacobs, Miriam N; Covaci, Adrian; Gheorghe, Adriana; Schepens, Paul

2004-03-24

In addition to being used in the food and animal feed industry, fish oils have also been used traditionally as dietary supplements. Due to the presence of long-chain n-3 fatty acids, fish oils have therapeutic benefits in the prevention and treatment of cardiovascular, immunological, and arthritic diseases, as well as childhood deficiency diseases such as rickets, because of a high content of vitamin D. However, fish oils are also susceptible to contamination with lipophilic organic chemicals that are now ubiquitous contaminants of marine ecosystems. Many vegetable oils are sources of the shorter chain precursor forms of n-3 fatty acids, and in recent years the specialist dietary supplement market has expanded to include these oils in a variety of different formulations. This paper reports analytical results of selected contaminants, including polychlorinated biphenyls, organochlorine pesticides, and polybrominated diphenyl ethers, for a range of commercially available n-3 fatty acid rich fish and vegetable oil dietary supplements. Using principal component analysis, the values are compared with historic samples to elucidate time trends in contamination profiles. Levels of contaminants are discussed in relation to the nutritional benefits to the consumer of long- and short-chain forms of n-3 fatty acids.

Improving protein production of indigenous microalga Chlorella vulgaris FSP-E by photobioreactor design and cultivation strategies.

PubMed

Chen, Chun-Yen; Lee, Po-Jen; Tan, Chung Hong; Lo, Yung-Chung; Huang, Chieh-Chen; Show, Pau Loke; Lin, Chih-Hung; Chang, Jo-Shu

2015-06-01

Fish meal is currently the major protein source for commercial aquaculture feed. Due to its unstable supply and increasing price, fish meal is becoming more expensive and its availability is expected to face significant challenges in the near future. Therefore, feasible alternatives to fish meal are urgently required. Microalgae have been recognized as the most promising candidates to replace fish meal because the protein composition of microalgae is similar to fish meal and the supply of microalgae-based proteins is sustainable. In this study, an indigenous microalga (Chlorella vulgaris FSP-E) with high protein content was selected, and its feasibility as an aquaculture protein source was explored. An innovative photobioreactor (PBR) utilizing cold cathode fluorescent lamps as an internal light source was designed to cultivate the FSP-E strain for protein production. This PBR could achieve a maximum biomass and protein productivity of 699 and 365 mg/L/day, respectively, under an optimum urea and iron concentration of 12.4 mM and 90 μM, respectively. In addition, amino acid analysis of the microalgal protein showed that up to 70% of the proteins in this microalgal strain consist of indispensable amino acids. Thus, C. vulgaris FSP-E appears to be a viable alternative protein source for the aquaculture industry. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Relative Condition Factors of Fish as Bioindicators One Year after the Deepwater Horizon Oil Spill

DTIC Science & Technology

2012-02-01

parts of the water column, and they have different but somewhat overlapping feeding habits . Black drum eat at the seafloor and prefer shellfish like...oysters and bottom-dwelling crustaceans like crab (Matlock 1990). Red drum feed throughout the water column and prefer to eat shrimp, smaller fish... Feeding habits of red drum (Sciaenops ocellatus) in Galveston Bay, Texas: Seasonal diet variation and predator- prey size relationships. Estuaries and

Compensatory responses in common carp (Cyprinus carpio) under ammonia exposure: additional effects of feeding and exercise.

PubMed

Diricx, Marjan; Sinha, Amit Kumar; Liew, Hon Jung; Mauro, Nathalie; Blust, Ronny; De Boeck, Gudrun

2013-10-15

Ammonia is an environmental pollutant that is toxic to all aquatic animals. The toxic effects of ammonia can be modulated by other physiological processes such as feeding and swimming. In this study, we wanted to examine these modulating effects in common carp (Cyprinus carpio). Fish were either fed (2% body weight) or starved (unfed for seven days prior to the sampling), and swimming at a sustainable, routine swimming speed or swum to exhaustion, while being exposed chronically (up to 28 days) to high environmental ammonia (HEA, 1 mg/L ~58.8 μmol/L as NH4Cl at pH 7.9). Swimming performance (critical swimming speed, Ucrit) and metabolic responses such as oxygen consumption rate (MO2), ammonia excretion rate (Jamm), ammonia quotient, liver and muscle energy budget (glycogen, lipid and protein), plasma ammonia and lactate, as well as plasma ion concentrations (Na(+), Cl(-), K(+) and Ca(2+)) were investigated in order to understand metabolic and iono-regulatory consequences of the experimental conditions. Cortisol plays an important role in stress and in both the regulation of energy and the ion homeostasis; therefore plasma cortisol was measured. Results show that during HEA, Jamm was elevated to a larger extent in fed fish and they were able to excrete much more efficiently than the starved fish. Consequently, the build-up of ammonia in plasma of HEA exposed fed fish was much slower. MO2 increased considerably in fed fish after exposure to HEA and was further intensified during exercise. During exposure to HEA, the level of cortisol in plasma augmented in both the feeding regimes, but the effect of HEA was more pronounced in starved fish. Energy stores dropped for both fed and the starved fish with the progression of the exposure period and further declined when swimming to exhaustion. Overall, fed fish were less affected by HEA than starved fish, and although exercise exacerbated the toxic effect in both feeding treatments, this was more pronounced in starved fish. This suggests that fish become more vulnerable to external ammonia during exercise, and feeding protects the fish against the adverse effects of high ammonia and exercise. Copyright © 2013 Elsevier B.V. All rights reserved.

Trace elements in farmed fish (Cyprinus carpio, Ctenopharyngodon idella and Oncorhynchus mykiss) from Beijing: implication from feed.

PubMed

Jiang, Haifeng; Qin, Dongli; Mou, Zhenbo; Zhao, Jiwei; Tang, Shizhan; Wu, Song; Gao, Lei

2016-06-01

Concentrations of 30 trace elements, Li, V, Cr, Mn, Fe, Ni, Cu, Mo, Zn, Se, Sr, Co, Al, Ti, As, Cs, Sc, Te, Ba, Ga, Pb, Sn, Cd, Sb, Ag, Tm, TI, Be, Hg and U in major cultured freshwater fish species (common carp-Cyprinus carpio, grass carp-Ctenopharyngodon idella and rainbow trout-Oncorhynchus mykiss) with the corresponding feed from 23 fish farms in Beijing, China, were investigated. The results revealed that Fe, Zn, Cu, Mn, Sr, Se were the major accumulated essential elements and Al, Ti were the major accumulated non-essential elements, while Mo, Co, Ga, Sn, Cd, Sb, Ag, Tm, U, TI, Be, Te, Pb and Hg were hardly detectable. Contents of investigated trace elements were close to or much lower than those in fish from other areas in China. Correlation analysis suggested that the elemental concentrations in those fish species were relatively constant and did not vary much with the fish feed. In comparison with the limits for aquafeeds and fish established by Chinese legislation, Cd in 37.5% of rainbow trout feeds and As in 20% of rainbow trout samples exceeded the maximum limit, assuming that inorganic As accounts for 10% of total As. Further health risk assessment showed that fish consumption would not pose risks to consumers as far as non-essential element contaminants are concerned. However, the carcinogenic risk of As in rainbow trout for the inhabitants in Beijing exceeded the acceptable level of 10(-)(4), to which more attention should be paid.

Role of mariculture in the loading and speciation of mercury at the coast of the East China Sea.

PubMed

Liang, Peng; Gao, Xuefei; You, Qiongzhi; Zhang, Jin; Cao, Yucheng; Zhang, Chan; Wong, Ming-Hung; Wu, Sheng-Chun

2016-11-01

The effects of mariculture on mercury (Hg) contamination and speciation in water, sediment and cultured fish in a typical mariculture zone located in Xiangshan bay, Zhejiang province, east China, were studied. Water, sediment and fish samples were collected from mariculture sites (MS) and from corresponding reference sites (RS) 2500 m away from the MS. The THg concentration in overlying water in Xiangshan bay reached as high as 16.6 ± 19.5 ng L -1 , indicating that anthropogenic sources in this bay may contribution on Hg contamination in overlying water. Mariculture activities resulted in an increase in THg concentration in water from surface and bottom layers, which may be attributed to the discharge of domestic sewage and the accumulation of unconsumed fish feed and fish excreta in the benthic environment. Methylmercury (MeHg) concentrations in the bottom layer of overlying water and top surface layer of porewater underneath MS were higher than at RS, implying that mariculture activities promote Hg methylation in the interface between sediments and water. In addition, the concentrations of MeHg in sediment and porewater were significantly higher in summer than winter. It was observed that THg and MeHg contents in the muscle of blackhead seabream (Acanthopagrus schlegelii) (fed by the trash fish) were significantly higher (p < 0.001) than those in red snapper (Lutjanus campechanus) or perch (Perca fluviatilis) (fed by pellet fish feed). The THg and MeHg concentrations in the fish meat were closely related to the feeding mode, which indicate that fish feed rather than environmental media is the major pathway for Hg accumulation in fish muscle. Copyright © 2016 Elsevier Ltd. All rights reserved.

Selective feeding by coral reef fishes on coral lesions associated with brown band and black band disease

NASA Astrophysics Data System (ADS)

Chong-Seng, K. M.; Cole, A. J.; Pratchett, M. S.; Willis, B. L.

2011-06-01

Recent studies have suggested that corallivorous fishes may be vectors for coral disease, but the extent to which fishes actually feed on and thereby potentially transmit coral pathogens is largely unknown. For this study, in situ video observations were used to assess the level to which fishes fed on diseased coral tissues at Lizard Island, northern Great Barrier Reef. Surveys conducted at multiple locations around Lizard Island revealed that coral disease prevalence, especially of brown band disease (BrB), was higher in lagoon and backreef locations than in exposed reef crests. Accordingly, video cameras were deployed in lagoon and backreef habitats to record feeding by fishes during 1-h periods on diseased sections of each of 44 different coral colonies. Twenty-five species from five fish families (Blennidae, Chaetodontidae, Gobiidae, Labridae and Pomacentridae) were observed to feed on infected coral tissues of staghorn species of Acropora that were naturally infected with black band disease (BBD) or brown band disease (BrB). Collectively, these fishes took an average of 18.6 (±5.6 SE) and 14.3 (±6.1 SE) bites per hour from BBD and BrB lesions, respectively. More than 40% (408/948 bites) and nearly 25% (314/1319 bites) of bites were observed on lesions associated with BBD and BrB, respectively, despite these bands each representing only about 1% of the substratum available. Moreover, many corallivorous fishes ( Labrichthys unilineatus, Chaetodon aureofasciatus, C. baronessa, C. lunulatus, C. trifascialis, Cheiloprion labiatus) selectively targeted disease lesions over adjacent healthy coral tissues. These findings highlight the important role that reef fishes may play in the dynamics of coral diseases, either as vectors for the spread of coral disease or in reducing coral disease progression through intensive and selective consumption of diseased coral tissues.

Cold physiology: postprandial blood flow dynamics and metabolism in the Antarctic fish Pagothenia borchgrevinki.

PubMed

Sandblom, Erik; Davison, William; Axelsson, Michael

2012-01-01

Previous studies on metabolic responses to feeding (i.e. the specific dynamic action, SDA) in Antarctic fishes living at temperatures below zero have reported long-lasting increases and small peak responses. We therefore hypothesized that the postprandial hyperemia also would be limited in the Antarctic fish Pagothenia borchgrevinki. The proportion of cardiac output directed to the splanchnic circulation in unfed fish was 18%, which is similar to temperate fish species. Contrary to our prediction, however, gastrointestinal blood flow had increased by 88% at twenty four hours after feeding due to a significant increase in cardiac output and a significant decrease in gastrointestinal vascular resistance. While gastric evacuation time appeared to be longer than in comparable temperate species, digestion had clearly commenced twenty four hours after feeding as judged by a reduction in mass of the administered feed. Even so, oxygen consumption did not increase suggesting an unusually slowly developing SDA. Adrenaline and angiotensin II was injected into unfed fish to investigate neuro-humoral control mechanisms of gastrointestinal blood flow. Both agonists increased gastrointestinal vascular resistance and arterial blood pressure, while systemic vascular resistance was largely unaffected. The hypertension was mainly due to increased cardiac output revealing that the heart and the gastrointestinal vasculature, but not the somatic vasculature, are important targets for these agonists. It is suggested that the apparently reduced SDA in P. borchgrevinki is due to a depressant effect of the low temperature on protein assimilation processes occurring outside of the gastrointestinal tract, while the gastrointestinal blood flow responses to feeding and vasoactive substances resemble those previously observed in temperate species.

Development of observational learning during school formation in jack mackerel Trachurus japonicus juveniles.

PubMed

Takahashi, Kohji; Masuda, Reiji; Yamashita, Yoh

2014-03-01

We assessed whether the development of observational learning in jack mackerel Trachurus japonicus juveniles corresponds with that of their schooling behaviour. Schooling behaviour was quantitatively analyzed by nearest neighbour distance and separation angle in two size classes of fish, 20-mm and 40-mm in body length. Observer and non-observer fish with matching sizes were conditioned to pellets by temporarily stopping aeration. Observer fish were provided with five observation trials of other individuals feeding near an air stone when aeration was stopped. After the observation trial, fish were conditioned to pellets with the stop of aeration, and then the learning process was evaluated by the increase in the association with the feeding area when aeration was stopped. In 20-mm fish, which were at an immature stage of schooling behaviour, there was no difference in the learning process between observer and non-observer fish. In contrast, 40-mm fish were confirmed to have a well-developed schooling behaviour, and the observer learnt the feeding area more efficiently than the non-observer. This study provides evidence that observational learning develops along with the development of the social interaction. Copyright © 2013 Elsevier B.V. All rights reserved.

The Complete and Updated "Rotifer Polyculture Method" for Rearing First Feeding Zebrafish

PubMed Central

Lawrence, Christian; Best, Jason; Cockington, Jason; Henry, Eric C.; Hurley, Shane; James, Althea; Lapointe, Christopher; Maloney, Kara; Sanders, Erik

2016-01-01

The zebrafish (Danio rerio) is a model organism of increasing importance in many fields of science. One of the most demanding technical aspects of culture of this species in the laboratory is rearing first-feeding larvae to the juvenile stage with high rates of growth and survival. The central management challenge of this developmental period revolves around delivering highly nutritious feed items to the fish on a nearly continuous basis without compromising water quality. Because larval zebrafish are well-adapted to feed on small zooplankton in the water column, live prey items such as brachionid rotifers, Artemia, and Paramecium are widely recognized as the feeds of choice, at least until the fish reach the juvenile stage and are able to efficiently feed on processed diets. This protocol describes a method whereby newly hatched zebrafish larvae are cultured together with live saltwater rotifers (Brachionus plicatilis) in the same system. This polyculture approach provides fish with an "on-demand", nutrient-rich live food source without producing chemical waste at levels that would otherwise limit performance. Importantly, because the system harnesses both the natural high productivity of the rotifers and the behavioral preferences of the fish, the labor involved with maintenance is low. The following protocol details an updated, step-by-step procedure that incorporates rotifer production (scalable to any desired level) for use in a polyculture of zebrafish larvae and rotifers that promotes maximal performance during the first 5 days of exogenous feeding. PMID:26863035

The Complete and Updated "Rotifer Polyculture Method" for Rearing First Feeding Zebrafish.

PubMed

Lawrence, Christian; Best, Jason; Cockington, Jason; Henry, Eric C; Hurley, Shane; James, Althea; Lapointe, Christopher; Maloney, Kara; Sanders, Erik

2016-01-17

The zebrafish (Danio rerio) is a model organism of increasing importance in many fields of science. One of the most demanding technical aspects of culture of this species in the laboratory is rearing first-feeding larvae to the juvenile stage with high rates of growth and survival. The central management challenge of this developmental period revolves around delivering highly nutritious feed items to the fish on a nearly continuous basis without compromising water quality. Because larval zebrafish are well-adapted to feed on small zooplankton in the water column, live prey items such as brachionid rotifers, Artemia, and Paramecium are widely recognized as the feeds of choice, at least until the fish reach the juvenile stage and are able to efficiently feed on processed diets. This protocol describes a method whereby newly hatched zebrafish larvae are cultured together with live saltwater rotifers (Brachionus plicatilis) in the same system. This polyculture approach provides fish with an "on-demand", nutrient-rich live food source without producing chemical waste at levels that would otherwise limit performance. Importantly, because the system harnesses both the natural high productivity of the rotifers and the behavioral preferences of the fish, the labor involved with maintenance is low. The following protocol details an updated, step-by-step procedure that incorporates rotifer production (scalable to any desired level) for use in a polyculture of zebrafish larvae and rotifers that promotes maximal performance during the first 5 days of exogenous feeding.

36 CFR 13.1142 - Can I appeal denial of my commercial fishing lifetime access permit application?

Code of Federal Regulations, 2010 CFR

2010-07-01

... commercial fishing lifetime access permit application? 13.1142 Section 13.1142 Parks, Forests, and Public... Regulations-Glacier Bay National Park and Preserve Commercial Fishing § 13.1142 Can I appeal denial of my... lifetime access permit is denied, the superintendent will provide the applicant with the reasons for the...

Morphology, Kinematics, and Dynamics: The Mechanics of Suction Feeding in Fishes.

PubMed

Day, Steven W; Higham, Timothy E; Holzman, Roi; Van Wassenbergh, Sam

2015-07-01

Suction feeding is pervasive among aquatic vertebrates, and our understanding of the functional morphology and biomechanics of suction feeding has recently been advanced by combining experimental and modeling approaches. Key advances include the visualization of the patterns of flow in front of the mouth of a feeding fish, the measurement of pressure inside their mouth cavity, and the employment of analytical and computational models. Here, we review the key components of the morphology and kinematics of the suction-feeding system of anatomically generalized, adult ray-finned fishes, followed by an overview of the hydrodynamics involved. In the suction-feeding apparatus, a strong mechanistic link among morphology, kinematics, and the capture of prey is manifested through the hydrodynamic interactions between the suction flows and solid surfaces (the mouth cavity and the prey). It is therefore a powerful experimental system in which the ecology and evolution of the capture of prey can be studied based on first principals. © The Author 2015. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Social interactions among grazing reef fish drive material flux in a coral reef ecosystem.

PubMed

Gil, Michael A; Hein, Andrew M

2017-05-02

In human financial and social systems, exchanges of information among individuals cause speculative bubbles, behavioral cascades, and other correlated actions that profoundly influence system-level function. Exchanges of information are also widespread in ecological systems, but their effects on ecosystem-level processes are largely unknown. Herbivory is a critical ecological process in coral reefs, where diverse assemblages of fish maintain reef health by controlling the abundance of algae. Here, we show that social interactions have a major effect on fish grazing rates in a reef ecosystem. We combined a system for observing and manipulating large foraging areas in a coral reef with a class of dynamical decision-making models to reveal that reef fish use information about the density and actions of nearby fish to decide when to feed on algae and when to flee foraging areas. This "behavioral coupling" causes bursts of feeding activity that account for up to 68% of the fish community's consumption of algae. Moreover, correlations in fish behavior induce a feedback, whereby each fish spends less time feeding when fewer fish are present, suggesting that reducing fish stocks may not only reduce total algal consumption but could decrease the amount of algae each remaining fish consumes. Our results demonstrate that social interactions among consumers can have a dominant effect on the flux of energy and materials through ecosystems, and our methodology paves the way for rigorous in situ measurements of the behavioral rules that underlie ecological rates in other natural systems.

Feeding ecology of some fish species occurring in artisanal fishery of Socotra Island (Yemen).

PubMed

Hassan Ali', Mohammed Kaed; Belluscio, Andrea; Ventura, Daniele; Ardizzone, Giandomenico

2016-04-30

The demersal species Lethrinus borbonicus, Lethrinus mahsena, Lethrinus microdon, Lethrinus nebulosus, Lutjanus bohar, Lutjanus gibbus, Lutjanus kasmira, Epinephelus fasciatus, Epinephelus stoliczkae, Carangoides gymnostethus and Euthynnus affinis are important coastal fishes species of the northern coast of Socotra (Yemen), exploited by local fishery. The biology and feeding ecology of these species are poorly known in the area. A total of 1239 specimens were sampled from the main fishing landing site of the island (Hadibo). Total length and weight were measured, stomach contents were analyzed, diet overlap, Fulton's Condition index, and trophic levels were estimated. C. gymnostethus, L. microdon and L. kasmira occupied the highest position (T=4.50), L. nebulosus occupied the lower one (TL=3.41). The role of the increasing abundance of small pelagic fish in the diet of many species after the upwelling event is evident, but also different feeding strategies are reported, according to fish ecology. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of Fishing and Fishing Closures on Beach Clams: Experimental Evaluation across Commercially Fished and Non-Fished Beaches before and during Harvesting

PubMed Central

Gray, Charles A.

2016-01-01

Management responses to reconcile declining fisheries typically include closed areas and times to fishing. This study evaluated this strategy for a beach clam fishery by testing the hypothesis that changes in the densities and size compositions of clams from before to during harvesting would differ between commercially fished and non-fished beaches. Sampling was spatially stratified across the swash and dry sand habitats on each of two commercially fished and two non-fished beaches, and temporally stratified across three six-week blocks: before, early and late harvesting. Small-scale spatio-temporal variability in the densities and sizes of clams was prevalent across both habitats and the components of variation were generally greatest at the lowest levels examined. Despite this, differences in the densities and sizes of clams among individual beaches were evident, but there were few significant differences across the commercially fished versus non-fished beaches from before to during harvesting. There was no evidence of reduced densities or truncated size compositions of clams on fished compared to non-fished beaches, contrasting reports of some other organisms in protected areas. This was probably due to a combination of factors, including the current levels of commercial harvests, the movements and other local-scale responses of clams to ecological processes acting independently across individual beaches. The results identify the difficulties in detecting fishing-related impacts against inherent levels of variability in clam populations. Nevertheless, continued experimental studies that test alternate management arrangements may help refine and determine the most suitable strategies for the sustainable harvesting of beach clams, ultimately enhancing the management of sandy beaches. PMID:26731102

Effects of Fishing and Fishing Closures on Beach Clams: Experimental Evaluation across Commercially Fished and Non-Fished Beaches before and during Harvesting.

PubMed

Gray, Charles A

2016-01-01

Management responses to reconcile declining fisheries typically include closed areas and times to fishing. This study evaluated this strategy for a beach clam fishery by testing the hypothesis that changes in the densities and size compositions of clams from before to during harvesting would differ between commercially fished and non-fished beaches. Sampling was spatially stratified across the swash and dry sand habitats on each of two commercially fished and two non-fished beaches, and temporally stratified across three six-week blocks: before, early and late harvesting. Small-scale spatio-temporal variability in the densities and sizes of clams was prevalent across both habitats and the components of variation were generally greatest at the lowest levels examined. Despite this, differences in the densities and sizes of clams among individual beaches were evident, but there were few significant differences across the commercially fished versus non-fished beaches from before to during harvesting. There was no evidence of reduced densities or truncated size compositions of clams on fished compared to non-fished beaches, contrasting reports of some other organisms in protected areas. This was probably due to a combination of factors, including the current levels of commercial harvests, the movements and other local-scale responses of clams to ecological processes acting independently across individual beaches. The results identify the difficulties in detecting fishing-related impacts against inherent levels of variability in clam populations. Nevertheless, continued experimental studies that test alternate management arrangements may help refine and determine the most suitable strategies for the sustainable harvesting of beach clams, ultimately enhancing the management of sandy beaches.

Parrotfish size: a simple yet useful alternative indicator of fishing effects on Caribbean reefs?

PubMed

Vallès, Henri; Oxenford, Hazel A

2014-01-01

There is great need to identify simple yet reliable indicators of fishing effects within the multi-species, multi-gear, data-poor fisheries of the Caribbean. Here, we investigate links between fishing pressure and three simple fish metrics, i.e. average fish weight (an estimate of average individual fish size), fish density and fish biomass, derived from (1) the parrotfish family, a ubiquitous herbivore family across the Caribbean, and (2) three fish groups of "commercial" carnivores including snappers and groupers, which are widely-used as indicators of fishing effects. We hypothesize that, because most Caribbean reefs are being heavily fished, fish metrics derived from the less vulnerable parrotfish group would exhibit stronger relationships with fishing pressure on today's Caribbean reefs than those derived from the highly vulnerable commercial fish groups. We used data from 348 Atlantic and Gulf Rapid Reef Assessment (AGRRA) reef-surveys across the Caribbean to assess relationships between two independent indices of fishing pressure (one derived from human population density data, the other from open to fishing versus protected status) and the three fish metrics derived from the four aforementioned fish groups. We found that, although two fish metrics, average parrotfish weight and combined biomass of selected commercial species, were consistently negatively linked to the indices of fishing pressure across the Caribbean, the parrotfish metric consistently outranked the latter in the strength of the relationship, thus supporting our hypothesis. Overall, our study highlights that (assemblage-level) average parrotfish size might be a useful alternative indicator of fishing effects over the typical conditions of most Caribbean shallow reefs: moderate-to-heavy levels of fishing and low abundance of highly valued commercial species.

Comparison of the effects of dietary single and multi-probiotics on growth, non-specific immune responses and disease resistance in starry flounder, Platichthys stellatus.

PubMed

Park, Youngjin; Moniruzzaman, Mohammad; Lee, Seunghan; Hong, Jeongwhui; Won, Seonghun; Lee, Jong Min; Yun, Hyeonho; Kim, Kang-Woong; Ko, Daegyun; Bai, Sungchul C

2016-12-01

An 8-week feeding trial was conducted to evaluate the effects of dietary probiotics on growth performance and non-specific immune responses in starry flounder, Platichthys stellatus. Fish averaging 46.5 ± 0.65 g (mean ± SD) were fed one of the six experimental diets; one control (Cont), and five other diets were prepared by supplementing single-probiotics 1 (Bacillus subtilis; SP 1 , 2 × 10 9  CFU kg -1 diet), single-probiotics 2 (Bacillus licheniformis; SP 2 , 2 × 10 9  CFU kg -1 diet), multi-probiotics 1 (Bacillus subtilis + Bacillus licheniformis; MP 1 , 2 × 10 9  CFU kg -1 diet), multi-probiotics 2 (commercial probiotics; Bacillus subtills + Bacillus licheniformis + Paenibacillus polymyxa + Aspergillus oryzae + Saccharomyces cerevisiae; MP 2 , 2 × 10 9  CFU kg -1 diet) and oxytetracycline (OTC) at 5 g OTC kg -1 diet. At the end of 8 weeks feeding trial, weight gain (WG) and specific growth rate (SGR) of fish fed SP 1 , MP 1 and MP 2 diets were significantly higher than those of fish fed control diet (P < 0.05). Superoxide dismutase (SOD) activity of fish fed MP 2 diet was significantly higher than those of fish fed OTC diet (P < 0.05). Nitro blue tetrazolium (NBT) activity and lysozyme activity of fish fed SP 1 , MP 1 and MP 2 diets were significantly higher than those of fish fed OTC diet (P < 0.05). However, there was no significant difference among fish fed SP 1 , SP 2 , MP 1 and MP 2 diets. During the Edwardsiella tarda challenge test, the first mortality occurred on day 2. After the 14 days challenge test, cumulative survival rate of fish fed MP 1 and MP 2 diets were significantly higher than those of fish fed control diet (P < 0.05). However, there was no significant difference among fish fed SP 1 , SP 2 , MP 1 , MP 2 and OTC diets in survival rate at the termination of the challenge test. Although there was little advantage in immunological parameters with fish fed MP diets, single and multi-probiotics were equally effective statistically. These results demonstrated that single or multi-probiotics had equal beneficial effect as an antibiotic replacer in terms of growth performance, non-specific immune responses and disease resistance in starry flounder. Copyright © 2016 Elsevier Ltd. All rights reserved.

Atypical feeding behavior of Long-tailed Ducks in the wake of a commercial fishing boat while clamming

USGS Publications Warehouse

Perry, Matthew; Osenton, Peter C.; White, Timothy P.

2017-01-01

A foraging group of Clangula hyemalis (Long-tailed Duck) was observed on 10 February 2010 diving behind a commercial boat that was clamming near Monomoy Island, Nantucket Sound, MA. We used a shotgun to collect 9 of the ducks, and our analyses of gizzard and gullet (esophagus and proventriculus) revealed 37 food items in the gizzard and 16 in the gullet. Mollusca were the dominant food in the gizzard (49%), whereas Crustacea were dominant in the gullet (57%). Crustacea were the second most important food in the gizzard (38%), whereas Mollusca were the second most important food in the gullet (31%). Relatively high volumes of the Amphipoda Caprella sp. (skeleton shrimp) and the Decopoda Crangon septemspinosa (Sand Shrimp) were recorded in the gullet and gizzard. Ensis directus (Atlantic Jackknife Clam) formed the greatest volume of Mollusca in the gizzard (15%) and in the gullet (15%). Long-tailed Ducks had fed on this Bivalvia and several other species of Mollusca that had no shell or broken shell when consumed. Many of the food organisms were apparently dislodged and some damaged by the clamming operation creating an opportunistic feeding strategy for the Long-tailed Ducks.

Temperature affects the timing of spawning and migration of North Sea mackerel

NASA Astrophysics Data System (ADS)

Jansen, Teunis; Gislason, Henrik

2011-01-01

Climate change accentuates the need for knowing how temperature impacts the life history and productivity of economically and ecologically important species of fish. We examine the influence of temperature on the timing of the spawning and migrations of North Sea Mackerel using data from larvae CPR surveys, egg surveys and commercial landings from Danish coastal fisheries in the North Sea, Skagerrak, Kattegat and inner Danish waters. The three independent sources of data all show that there is a significant relationship between the timing of spawning and sea surface temperature. Large mackerel are shown to arrive at the feeding areas before and leave later than small mackerel and the sequential appearance of mackerel in each of the feeding areas studied supports the anecdotal evidence for an eastward post-spawning migration. Occasional commercial catches taken in winter in the Sound N, Kattegat and Skagerrak together with catches in the first quarter IBTS survey furthermore indicate some overwintering here. Significant relationships between temperature and North Sea mackerel spawning and migration have not been documented before. The results have implications for mackerel resource management and monitoring. An increase in temperature is likely to affect the timing and magnitude of the growth, recruitment and migration of North Sea mackerel with subsequent impacts on its sustainable exploitation.

Polychlorinated Biphenyls (PCBs) in Predator and Bottom-Feeding Fish from Abiquiu and Cochiti Reservoirs in North-Central New Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

G.J. Gonzales, P.R. Fresquez

2006-03-01

Concern has existed for years that the Los Alamos National Laboratory (LANL), a complex of nuclear weapons research and support facilities, has released polychlorinated biphenyls (PCBs) to the environment that may have reached adjacent bodies of water through canyons that connect them. In 1997, we began measuring PCBs in fish in the Rio Grande upstream and downstream of ephemeral streams that cross LANL and later began sampling fish in Abiquiu and Cochiti reservoirs, which are situated on the Rio Chama and Rio Grande upstream and downstream of LANL, respectively. In 2005, six species of fish from Abiquiu and Cochiti reservoirsmore » were collected and the edible portion (fillets) was analyzed for 209 possible PCB congeners. Fish from the reservoirs were last sampled in 2001. Mean total PCB concentrations in fish from Abiquiu Reservoir ({mu} = 2.4 ng/g) were statistically similar ({alpha} = 0.01; P (T{le}t) [range = 0.23-0.71]) to mean total PCB concentrations in fish from Cochiti Reservoir ({mu} = 2.7 ng/g), implying that LANL is not the source of PCBs in fish in Cochiti Reservoir. The levels of PCBs in fish from Cochiti Reservoir generally appear to be declining, at least since 2001, which is when PCB levels might have peaked resulting from storm water runoff after the Cerro Grande Fire. Although a PCB ''fingerprinting'' method can be used to relate PCB ''signatures'' in one area to signatures in another area, this method of implicating the source of PCBs cannot be effectively used for biota because they alter the PCB signature through metabolic processes. Regardless of the source of the PCBs, certain species of fish (catfish and carpsuckers) at both Abiquiu and Cochiti reservoirs continue to harbor levels of PCBs that could be harmful to human health if they are consistently eaten over a long period of time. Bottom-feeding fish (carpsucker and catfish) from Cochiti Reservoir contained statistically higher levels of total PCBs ({mu} = 4.25 ng/g-fillet-wet) than predator fish (walleye, northern pike, bass) ({mu} = 1.67 ng/g) and the bottom-feeding fish had levels of PCBs that fall into a restricted consumption category in U.S. Environmental Protection Agency (EPA) charts. Similarly, bottom-feeding fish from Abiquiu Reservoir also contained statistically higher levels of total PCBs ({mu} = 4.25 ng/g-wet) than predator fish (walleye, bass) ({mu} = 0.68 ng/g-wet) and only the bottom-feeding fish had levels of PCBs that fall into a restricted consumption category in the EPA charts.« less

Economic values of growth and feed efficiency for fish farming in recirculating aquaculture system with density and nitrogen output limitations: a case study with African catfish (Clarias gariepinus).

PubMed

Besson, M; Komen, H; Aubin, J; de Boer, I J M; Poelman, M; Quillet, E; Vancoillie, C; Vandeputte, M; van Arendonk, J A M

2014-12-01

In fish farming, economic values (EV) of breeding goal traits are lacking, even though they are key parameters when defining selection objectives. The aim of this study was to develop a bioeconomic model to estimate EV of 2 traits representing production performances in fish farming: the thermal growth coefficient (TGC) and the feed conversion ratio (FCR). This approach was applied to a farm producing African catfish (Clarias gariepinus) in a recirculating aquaculture system (RAS). In the RAS, 2 factors could limit production level: the nitrogen treatment capacity of the biofilter or the fish density in rearing tanks at harvest. Profit calculation includes revenue from fish sales, cost of juveniles, cost of feed, cost of waste water treatment, and fixed costs. In the reference scenario, profit was modeled to zero. EV were calculated as the difference in profit per kilogram of fish between the current population mean for both traits (µt) and the next generation of selective breeding (µt+Δt) for either TGC or FCR. EV of TGC and FCR were calculated for three generations of hypothetical selection on either TGC or FCR (respectively 6.8% and 7.6% improvement per generation). The results show that changes in TGC and FCR can affect both the number of fish that can be stocked (number of batches per year and number of fish per batch) and the factor limiting production. The EV of TGC and FCR vary and depend on the limiting factors. When dissolved NH3-N is the limiting factor for both µt and µt+Δt, increasing TGC decreases the number of fish that can be stocked but increases the number of batches that can be grown. As a result, profit remains constant and EVTGC is zero. Increasing FCR, however, increases the number of fish stocked and the ratio of fish produced per kilogram of feed consumed ("economic efficiency"). The EVFCR is 0.14 €/kg of fish, and profit per kilogram of fish increases by about 10%. When density is the limiting factor for both µt and µt+Δt, the number of fish stocked per batch is fixed; therefore, extra profit is obtained by increasing either TGC, which increases the annual number of batches, or by decreasing FCR, which decreases annual feed consumption. EVTGC is 0.03 €/kg of fish and EVFCR is 0.05-0.06 €/kg of fish. These results emphasize the importance of calculating economic values in the right context to develop efficient future breeding programs in aquaculture.

21 CFR 573.700 - Sodium nitrite.

Code of Federal Regulations, 2010 CFR

2010-04-01

..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive... as a preservative and color fixative in canned pet food containing fish, meat, and fish and meat... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium nitrite. 573.700 Section 573.700 Food and...

78 FR 20496 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Commercial Trap Sectors of the...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-05

... Caribbean, Gulf of Mexico, and South Atlantic; Commercial Trap Sectors of the Reef Fish and Spiny Lobster..., 2011, to control future access to the commercial trap sectors of the reef fish and spiny lobster... reef fish and spiny lobster fisheries should be controlled. DATES: Written comments must be received on...

Characterization of zebrafish larvae suction feeding flow using μPIV and optical coherence tomography

NASA Astrophysics Data System (ADS)

Pekkan, Kerem; Chang, Brian; Uslu, Fazil; Mani, Karthick; Chen, Chia-Yuan; Holzman, Roi

2016-07-01

The hydrodynamics of suction feeding is critical for the survival of fish larvae; failure to capture food during the onset of autonomous feeding can rapidly lead to starvation and mortality. Fluid mechanics experiments that investigate the suction feeding of suspended particles are limited to adult fishes, which operate at large Reynolds numbers. This manuscript presents the first literature results in which the external velocity fields generated during suction feeding of early zebrafish larvae (2500-20,000 μm total length) are reported using time-resolved microscopic particle image velocimetry. For the larval stages studied, the maximum peak suction velocity of the inflow bolus is measured at a finite distance from the mouth tip and ranges from 1 to 8 mm/s. The average pressure gradient and the velocity profile proximal to the buccal (mouth) cavity are calculated, and two distinct trends are identified. External recirculation regions and reverse flow feeding cycles are also observed and quantified. One of the unresolved questions in fish suction feeding is the shape and dynamics of the buccal cavity during suction feeding; optical coherence tomography imaging is found to be useful for reconstructing the mouth kinematics. The projected area of the mouth cavity during the feeding cycle varies up to 160 and 22 % for the transverse and mid-sagittal planes, respectively. These findings can inspire novel hydrodynamically efficient biomedical and microfluidic devices.

Comprehensive characterization of ethoxyquin transformation products in fish feed by traveling-wave ion mobility spectrometry coupled to quadrupole time-of-flight mass spectrometry.

PubMed

Negreira, Noelia; Regueiro, Jorge; Valdersnes, Stig; Berntssen, Marc H G; Ørnsrud, Robin

2017-05-01

Feed additives are typically used in intensive farming production over long periods, and hence, they can accumulate in farmed animal tissues. Concerns regarding the use of ethoxyquin as an antioxidant feed additive, have recently arisen due to its potential conversion into a series of transformation products (TPs). The aim of this work was to characterize the TPs of ethoxyquin in fish feed by a novel approach based on the use of traveling-wave ion mobility spectrometry (TWIMS) coupled to high-resolution quadrupole time-of-flight mass spectrometry (QTOFMS). First, ethoxyquin was oxidized under controlled conditions and the generated TPs were added to a comprehensive database. Atlantic salmon feeds were then screened for ethoxyquin TPs using both targeted and untargeted approaches. Twenty-seven TPs were tentatively identified during the oxidation experiments, fifteen of them also being present in the feed samples. In addition, ten other potential TPs were detected in fish feed following the untargeted approach. Thirty-one of these TPs have been reported for the first time in this work through the oxidation experiments and the feed samples. Therefore, this study provides valuable information on the oxidative fate of ethoxyquin in feed, which can be used for future evaluations of potential risk related to this additive. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of the squid viscera hydrolysate on growth performance and digestion in the red sea bream Pagrus major.

PubMed

Kondo, Fumitaka; Ohta, Takashi; Iwai, Toshiharu; Ido, Atsushi; Miura, Chiemi; Miura, Takeshi

2017-12-01

The improvement in feed efficiency is one of the most important subjects in fish culture. The development of feed, in terms of good intake, high growth performance, and high feed efficiency is needed. Squid viscera are one of the candidates for alternative material in improving feed efficiency in fish culture. In the present study, we described the dietary effect of the squid viscera hydrolysate (SVH) on the growth performance of the red sea bream. The addition of SVH to feed caused significant increases in feed intake, fork length, and body weight and produced a marked improvement in feed conversion after 4 weeks of feeding. Furthermore, the results of this feeding revealed that low dietary levels of SVH promote growth performance in the red sea bream. We physiologically analyzed digestion and appetite in fish fed diet containing SVH. SVH promoted the activity of hepatic trypsin and lipase, gene expression of stomach pepsin, hepatic lipase, and pyloric caeca trypsin, thereby improving the nutrient availability in red sea bream. Moreover, the mRNA expression of appetite regulating factor, such as brain NPY and stomach ghrelin was significantly improved by dietary SVH. Our current results indicate that dietary SVH as alternative material produced excellent effects on growth performance, which is dependent on the promoting effect on digestion and appetite in red sea bream.

Significant improvement of intestinal microbiota of gibel carp (Carassius auratus gibelio) after traditional Chinese medicine feeding.

PubMed

Wu, Z B; Gatesoupe, F-J; Li, T T; Wang, X H; Zhang, Q Q; Feng, D Y; Feng, Y Q; Chen, H; Li, A H

2018-03-01

Increasing attention has been attracted to intestinal microbiota, due to interactions with nutrition, metabolism and immune defence of the host. Traditional Chinese medicine (TCM) feed additives have been applied in aquaculture to improve fish health, but the interaction with fish gut microbiota is still poorly understood. This study aimed to explore the effect of adding TCM in feed on the intestinal microbiota of gibel carp (Carassius auratus gibelio). Bacterial communities of 16 fish intestinal contents and one water sample were characterized by high-throughput sequencing and analysis of the V4-V5 region of the 16S rRNA gene. The results showed that the composition and structure of the bacterial community were significantly altered by the TCM feeding. Some phyla increased markedly (Proteobacteria, Actinobacteria, Acidobacteria, etc.), while Fusobacteria were significantly reduced. Concurrently, the richness and diversity of the taxonomic units increased, and the microbiota composition of TCM-treated fish was more homogeneous among individuals. At the genus level, the addition of TCM tended to reduce the incidence of potential pathogens (Aeromonas, Acinetobacter and Shewanella), while stimulating the emergence of some potential probiotics (Lactobacillus, Lactococcus, Bacillus and Pseudomonas). These data suggested that the feed additive could regulate the fish intestinal microbiota by reinforcing the microbial balance. This study may provide useful information for further application of TCM for diseases prevention and stress management in aquaculture. © 2017 The Society for Applied Microbiology.

Water Quality Improvement of Media Culture for Tilapia (Oreochromis niloticus) with Cleaner Production Method

NASA Astrophysics Data System (ADS)

Haeruddin; Supriharyono; Febrianto, S.

2018-02-01

The tilapia (Oreochromis niloticus), is known as a high adaptability and brackish water tolerance fish. This fish is also has a meat with high protein content, that ranges about 65 -75%. Generally the tilapia is cultured using a conventional system with high density. It is caused degradation of water quality of media culture, and finally increase mortality rate of fish cultured. The application of tilapia cultivation with cleaner production method by giving enzyme into the feed to upgrade the efficiency of feed utilization, presumed that could improve the water quality of cultivation media. It is due to the lower of feed and feces residues. Therefore the concentration of toxic compounds, such as ammonia, nitrite and sulfide, will be lower. The experiments were conducted for 35 days with a completely factorial randomized design. The first factor was the dosage of enzyme in the feed, consisting of 4 dosages, and the second factor was the duration of the test fish maintenance (5 weeks). Water quality variables examined included ammonia, nitrite and sulfide. The results showed that enzyme dosage had no significantly impact on ammonia, nitrite and sulfide concentrations in the test media culture. However, the feeding with enzyme in low dosage, resulted less concentration of ammonia, nitrite and sulfide than it was without enzyme). The duration of fish cultured has significantly effect on the concentration of ammonia, nitrite and sulfide in the test media. While it is no significantly correlation between dosage and duration of maintenance.

Piscicultura. Productor Comercial de Peces. Guia Tecnica. Documento de trabajo, Programa de Educacion Agricola (Fish Farming. Commercial Fish Producer. Technical Guide. Curriculum Document, Agriculture Education Program).

ERIC Educational Resources Information Center

Puerto Rico State Dept. of Education, Hato Rey. Area for Vocational and Technical Education.

This curriculum guide begins with an introduction, course description, and description of the occupation of commercial fish farmer. A course outline covers five units: starting a business, establishing the fish farm, managing the enterprise, harvesting the fish, and administering the business. For each unit, the following are provided: terminal…

7 CFR 760.211 - Farm-raised fish payment calculations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 7 2012-01-01 2012-01-01 false Farm-raised fish payment calculations. 760.211 Section..., Honeybees, and Farm-Raised Fish Program § 760.211 Farm-raised fish payment calculations. (a) An eligible farm-raised fish producer may receive payments for fish feed losses due to an eligible adverse weather...

7 CFR 760.211 - Farm-raised fish payment calculations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 7 2011-01-01 2011-01-01 false Farm-raised fish payment calculations. 760.211 Section..., Honeybees, and Farm-Raised Fish Program § 760.211 Farm-raised fish payment calculations. (a) An eligible farm-raised fish producer may receive payments for fish feed losses due to an eligible adverse weather...

7 CFR 760.211 - Farm-raised fish payment calculations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 7 2014-01-01 2014-01-01 false Farm-raised fish payment calculations. 760.211 Section..., Honeybees, and Farm-Raised Fish Program § 760.211 Farm-raised fish payment calculations. (a) An eligible farm-raised fish producer may receive payments for fish feed losses due to an eligible adverse weather...

7 CFR 760.211 - Farm-raised fish payment calculations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 7 2013-01-01 2013-01-01 false Farm-raised fish payment calculations. 760.211 Section..., Honeybees, and Farm-Raised Fish Program § 760.211 Farm-raised fish payment calculations. (a) An eligible farm-raised fish producer may receive payments for fish feed losses due to an eligible adverse weather...

7 CFR 760.211 - Farm-raised fish payment calculations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Farm-raised fish payment calculations. 760.211 Section..., Honeybees, and Farm-Raised Fish Program § 760.211 Farm-raised fish payment calculations. (a) An eligible farm-raised fish producer may receive payments for fish feed losses due to an eligible adverse weather...

Successful selection of rainbow trout (Oncorhynchus mykiss) on their ability to grow with a diet completely devoid of fishmeal and fish oil, and correlated changes in nutritional traits.

PubMed

Callet, Thérèse; Médale, Françoise; Larroquet, Laurence; Surget, Anne; Aguirre, Pierre; Kerneis, Thierry; Labbé, Laurent; Quillet, Edwige; Geurden, Inge; Skiba-Cassy, Sandrine; Dupont-Nivet, Mathilde

2017-01-01

In the context of limited marine resources, the exponential growth of aquaculture requires the substitution of fish oil and fishmeal, the traditional components of fish feeds by terrestrial plant ingredients. High levels of such substitution are known to negatively impact fish performance such as growth and survival in rainbow trout (Oncorhynchus mykiss) as in other salmonids. In this respect, genetic selection is a key enabler for improving those performances and hence for the further sustainable development of aquaculture. We selected a rainbow trout line over three generations for its ability to survive and grow on a 100% plant-based diet devoid of both fish oil and fishmeal (V diet) from the very first meal. In the present study, we compared the control line and the selected line after 3 generations of selection, both fed either the V diet or a marine resources-based diet (M diet). The objective of the study was to assess the efficiency of selection and the consequences on various correlated nutritional traits: feed intake, feed efficiency, digestibility, composition of whole fish, nutrient retention and fatty acid (FA) profile. We demonstrated that the genetic variability present in our rainbow trout population can be selected to improve survival and growth. The major result of the study is that after only three generations of selection, selected fish fed the V diet grew at the same rate as the control line fed the M diet, whilst the relative reduction of body weight was 36.8% before the selection. This enhanced performance on the V diet seems to be mostly linked to a higher feed intake for the selected fish.

Successful selection of rainbow trout (Oncorhynchus mykiss) on their ability to grow with a diet completely devoid of fishmeal and fish oil, and correlated changes in nutritional traits

PubMed Central

Médale, Françoise; Larroquet, Laurence; Surget, Anne; Aguirre, Pierre; Kerneis, Thierry; Labbé, Laurent; Quillet, Edwige; Geurden, Inge; Skiba-Cassy, Sandrine; Dupont-Nivet, Mathilde

2017-01-01

In the context of limited marine resources, the exponential growth of aquaculture requires the substitution of fish oil and fishmeal, the traditional components of fish feeds by terrestrial plant ingredients. High levels of such substitution are known to negatively impact fish performance such as growth and survival in rainbow trout (Oncorhynchus mykiss) as in other salmonids. In this respect, genetic selection is a key enabler for improving those performances and hence for the further sustainable development of aquaculture. We selected a rainbow trout line over three generations for its ability to survive and grow on a 100% plant-based diet devoid of both fish oil and fishmeal (V diet) from the very first meal. In the present study, we compared the control line and the selected line after 3 generations of selection, both fed either the V diet or a marine resources-based diet (M diet). The objective of the study was to assess the efficiency of selection and the consequences on various correlated nutritional traits: feed intake, feed efficiency, digestibility, composition of whole fish, nutrient retention and fatty acid (FA) profile. We demonstrated that the genetic variability present in our rainbow trout population can be selected to improve survival and growth. The major result of the study is that after only three generations of selection, selected fish fed the V diet grew at the same rate as the control line fed the M diet, whilst the relative reduction of body weight was 36.8% before the selection. This enhanced performance on the V diet seems to be mostly linked to a higher feed intake for the selected fish. PMID:29059226

Effect of diet processing method and ingredient substitution on feed characteristics and survival of larval walleye, Sander vitreus

USGS Publications Warehouse

Barrows, F.T.; Lellis, W.A.

2006-01-01

Two methods were developed for the production of larval fish diets. The first method, microextrusion marumerization (MEM), has been tested in laboratory feeding trials for many years and produces particles that are palatable and water stable. The second method, particle-assisted rotational agglomeration (PARA), produced diets that have lower density than diets produced by MEM. Each method was used to produce diets in the 250- to 400- and 400- to 700-??m range and compared with a reference diet (Fry Feed Kyowa* [FFK]) for feeding larval walleye in two experiments. The effect of substituting 4% of the fish meal with freeze-dried artemia fines was also investigated. In the first experiment, 30-d survival was greater (P < 0.05) for fish fed a diet produced by PARA without Artemia (49.1.0%) than for fish fed the same diet produced by MEM (27.6%). The addition of Artemia to a diet produced by MEM did not increase survival of larval walleye. Fish fed the reference diet had 24.4% survival. In the second experiment, there was an effect of both processing method and Artemia supplementation, and an interaction of these effects, on survival. Fish fed a diet produced by PARA without Artemia supplementation had 48.4% survival, and fish fed the same diet produced by MEM had only 19.6% survival. Inclusion of 4% freeze-dried Artemia improved (P < 0.04) survival of fish fed MEM particles but not those fed PARA particles. Fish fed FFK had greater weight gain than fish fed other diets in both experiments. Data indicate that the PARA method of diet processing produces smaller, lower density particles than the MEM process and that diets produced by the PARA process support higher survival of larval walleye with low capital and operating costs. ?? Copyright by the World Aquaculture Society 2006.

[Mercury concentration of fish in Tokyo Bay and the surrounding sea area].

PubMed

Zhang, R; Kashima, Y; Matsui, M; Okabe, T; Doi, R

2001-07-01

Total mercury in the muscles of three fish species was analyzed in fish caught in Tokyo Bay and the surrounding sea areas, Sagami Bay and Choshi. Tokyo Bay is a semi-closed sea area surrounded by Tokyo, Kanagawa and Chiba prefectures. Sagami Bay and Choshi are open to the Pacific Ocean. A total of 412 fish consisting of northern whiting (Sillago japonica), flatfish (Limanda yokohamae) and sardine (Sardinops melanosticta) were caught in these areas over a 6 months period from November 1998 to April 1999. Total mercury concentration ranged from 0.008-0.092 microgram/g (wet wt.) in northern whiting, 0.006-0.065 microgram/g in flatfish and 0.001-0.045 microgram/g in sardine. All concentrations were below the restriction limit of fish mercury in Japan, 0.4 microgram/g of total mercury concentration. A significant correlation was found between mercury concentrations and body length or body weight in northern whiting and flatfish, irrespective of the sea area. A correlation was also found between mercury concentration in fish and their feeding habits: among the 3 species caught in the same area, crustacean feeding northern whiting had the highest, polychaete feeding flatfish moderate, and plankton feeding sardine had the lowest mercury concentration. In a comparison of mercury concentration in the same species caught in different sea areas, a higher concentration was noted in fish caught in the semi-closed sea area of Tokyo Bay, than in fish caught in the open sea areas of Sagami Bay and Choshi. This difference was most marked in fish caught at the bottom of Tokyo Bay and we considered that the mercury concentration of seawater and sediment in these areas was the cause of mercury accumulation in fish. These findings suggest that improved water quality control and environmental monitoring is necessary in semi-closed sea areas such as Tokyo Bay.

Hypoxia Impacts on Food Web Linkages in a Pelagic Ecosystem

NASA Astrophysics Data System (ADS)

Sato, M.; Horne, J. K.; Parker-Stetter, S. L.; Essington, T.; Keister, J. E.; Moriarty, P.; Li, L.

2016-02-01

Low dissolved oxygen (DO), or hypoxia, causes significant disturbances on aquatic organisms, but the consequences for key food web linkages is not well understood. Here, we tested how the intensity of low DO events governs the degree of spatial overlap between pelagic zooplanktivorous fish and their zooplankton prey, fish feeding rates, and community compositions of zooplankton. We hypothesized that the greater sensitivity of fish to DO compared to zooplankton would lead to diminished spatial overlap at moderate DO and reduced feeding rates of fish, while severe hypoxia would amplify spatial overlap by preventing zooplankton from using deep refuge habitats leading to increased fish feeding rates. We also hypothesized shifts in zooplankton community composition towards less energetically profitable taxa such as small copepods and gelatinous species. We used a combination of multifrequency acoustic and net sampling for detecting distributions and abundance of zooplankton and pelagic fish in Hood Canal, WA, a seasonally hypoxic fjord. We employed a sampling design which paired hypoxic regions of Hood Canal with normoxic regions sampled prior to, during, and after the onset of hypoxia in two years. Contrary to our hypotheses, we found that fish and zooplankton did not change their horizontal and vertical distributions during periods and in locations with low DO levels. Consequently, the vertical overlap between fish and zooplankton did not change with DO. Fish feeding rates and the dominant zooplankton prey did not change with hypoxia events. The apparent resilience of fish to low DO in our system may be explained by decreased metabolic oxygen demand due to cool temperatures, increased availability and accessibility to their prey in low DO waters, or potential increase in predation risk at shallower depth. This study highlights the importance of both temperature and DO, instead of hypoxia threshold alone, in evaluating the impacts of hypoxia on pelagic communities.

Morphology of seahorse head hydrodynamically aids in capture of evasive prey.

PubMed

Gemmell, Brad J; Sheng, Jian; Buskey, Edward J

2013-01-01

Syngnathid fish (seahorses, pipefish and sea dragons) are slow swimmers yet capture evasive prey (copepods) using a technique known as the 'pivot' feeding, which involves rapid movement to overcome prey escape capabilities. However, this feeding mode functions only at short range and requires approaching very closely to hydrodynamically sensitive prey without triggering an escape. Here we investigate the role of head morphology on prey capture using holographic and particle image velocimetry (PIV). We show that head morphology functions to create a reduced fluid deformation zone, minimizing hydrodynamic disturbance where feeding strikes occur (above the end of the snout), and permits syngnathid fish to approach highly sensitive copepod prey (Acartia tonsa) undetected. The results explain how these animals can successfully employ short range 'pivot' feeding effectively on evasive prey. The need to approach prey with stealth may have selected for a head shape that produces lower deformation rates than other fish.

The effect of protected sardine fish oil as feed supplement on ruminal fermentation

NASA Astrophysics Data System (ADS)

Pramono, A.; Widayati, D. T.; Handayanta, E.

2018-03-01

The research aims to evaluate the influence of protected sardine fish oil as feed supplement on ruminal fermentation (pH rumen fluid, ammonia concentration and volatile fatty acids production in the rumen). Protected feed supplement was produced from sardine fish oil and soybean meal, through two protection methods, they were saponification and microencapsulation. The experiment consists of two treatments i.e. P0: basal diet (control) and P1: basal diet + 3 % protected feed supplement. Each treatment was repeated 10 times. The kinetics observation of the pH rumen fluid, ammonia concentration and volatile fatty acids production were performed at incubation times 0, 2, 4 and 6 hours respectively. Data were analyzed using independent samples t-test. Results in cow with protected feed supplement showed that kinetics of pH rumen fluid: 7.23; 7.13; 6.90 and 6.76 respectively; ruminal ammonia concentration: 26.70; 31.06; 19.75 and 15.52 respectively; and volatile fatty acids production: 22.75; 26.08; 29.19 and 25.79 respectively. The results could be concluded that the effect of supplementation of protected sardine fish oil have an optimal of pH rumen fluid, ammonia concentration, and volatile fatty acids production so it did not interfere the ruminal fermentation in the rumen.

Relationships between species feeding traits and environmental conditions in fish communities: a three-matrix approach.

PubMed

Brind'Amour, Anik; Boisclair, Daniel; Dray, Stéphane; Legendre, Pierre

2011-03-01

Understanding the relationships between species biological traits and the environment is crucial to predicting the effect of habitat perturbations on fish communities. It is also an essential step in the assessment of the functional diversity. Using two complementary three-matrix approaches (fourth-corner and RLQ analyses), we tested the hypothesis that feeding-oriented traits determine the spatial distributions of littoral fish species by assessing the relationship between fish spatial distributions, fish species traits, and habitat characteristics in two Laurentian Shield lakes. Significant associations between the feeding-oriented traits and the environmental characteristics suggested that fish communities in small lakes (displaying low species richness) can be spatially structured. Three groups of traits, mainly categorized by the species spatial and temporal feeding activity, were identified. The water column may be divided in two sections, each of them corresponding to a group of traits related to the vertical distribution of the prey coupled with the position of the mouth. Lake areas of low structural complexity were inhabited by functional assemblages dominated by surface feeders while structurally more complex areas were occupied by mid-water and benthic feeders. A third group referring to the time of feeding activity was observed. Our work could serve as a guideline study to evaluate species traits x environment associations at multiple spatial scales. Our results indicate that three-matrix statistical approaches are powerful tools that can be used to study such relationships. These recent statistical approaches open up new research directions such as the study of spatially based biological functions in lakes. They also provide new analytical tools for determining, for example, the potential size of freshwater protected areas.

50 CFR 622.58 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

Code of Federal Regulations, 2014 CFR

2014-10-01

... commercial ACL, then during the following fishing year, if commercial landings reach or are projected to reach the commercial ACL, the AA will file a notification with the Office of the Federal Register to close the commercial sector for the remainder of that fishing year. The commercial ACL for royal red...

50 CFR 622.58 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

Code of Federal Regulations, 2013 CFR

2013-10-01

... commercial ACL, then during the following fishing year, if commercial landings reach or are projected to reach the commercial ACL, the AA will file a notification with the Office of the Federal Register to close the commercial sector for the remainder of that fishing year. The commercial ACL for royal red...

Regulation of feeding behavior and food intake by appetite-regulating peptides in wild-type and growth hormone-transgenic coho salmon.

PubMed

White, Samantha L; Volkoff, Helene; Devlin, Robert H

2016-08-01

Survival, competition, growth and reproductive success in fishes are highly dependent on food intake, food availability and feeding behavior and are all influenced by a complex set of metabolic and neuroendocrine mechanisms. Overexpression of growth hormone (GH) in transgenic fish can result in greatly enhanced growth rates, feed conversion, feeding motivation and food intake. The objectives of this study were to compare seasonal feeding behavior of non-transgenic wild-type (NT) and GH-transgenic (T) coho salmon (Oncorhynchus kisutch), and to examine the effects of intraperitoneal injections of the appetite-regulating peptides cholecystokinin (CCK-8), bombesin (BBS), glucagon-like peptide-1 (GLP-1), and alpha-melanocyte-stimulating hormone (α-MSH) on feeding behavior. T salmon fed consistently across all seasons, whereas NT dramatically reduced their food intake in winter, indicating the seasonal regulation of appetite can be altered by overexpression of GH in T fish. Intraperitoneal injections of CCK-8 and BBS caused a significant and rapid decrease in food intake for both genotypes. Treatment with either GLP-1 or α-MSH resulted in a significant suppression of food intake for NT but had no effect in T coho salmon. The differential response of T and NT fish to α-MSH is consistent with the melanocortin-4 receptor system being a significant pathway by which GH acts to stimulate appetite. Taken together, these results suggest that chronically increased levels of GH alter feeding regulatory pathways to different extents for individual peptides, and that altered feeding behavior in transgenic coho salmon may arise, in part, from changes in sensitivity to peripheral appetite-regulating signals. Copyright © 2016 Elsevier Inc. All rights reserved.

Saltatory ontogeny of fishes and sensitive early life stages for ecotoxicology tests.

PubMed

Belanger, Scott E; Balon, Eugene K; Rawlings, Jane M

2010-04-15

Fish display a wide range of developmental ontogenies. These distinctions have taxonomic, evolutionary, and ecological importance in addition to practical implications on the use of fish in aquatic toxicity tests. With respect to animal welfare, vertebrates are afforded protected or non-protected status in the European Union based upon whether they feed endogenously off the yolk or exogenously by procurement and ingestion of food. The concept of saltatory ontogeny suggests development is not gradual but proceeds in leaps separated by a series of stable developmental states. In this context, endogenous/exogenous feeding also distinguishes the developmental phases of embryo (egg), eleutheroembryo (feeding off the yolk sac) and larvae (exogenous feeding) in fish. The recent proposal for the Fish Embryo Test (FET) as an animal alternative to the standard fish acute toxicity test (OECD 203 and equivalent tests) puts a clear focus on the need to identify the non-protected and protected life intervals in test species as well as their sensitivities which coincides with the developmental phases identified in saltatory ontogeny. In this paper we described a method to quantify embryo, eleutheroembryo, and larva phases in Danio rerio, the zebrafish. Danio eleutheroembryos preyed upon 5 different protozoan species (Euglena, Euplotes, Paramecium aurelia, Paramecium bursaria and Paramecium multimicronucleatum) between 24 and 48hr following hatching (85-95% of fish, n=20 per species, 25 degrees C). Based upon these data it is recommended that testing of developing zebrafish embryos should be terminated between 24 and 48hr after hatching in order to be compliant with existing animal welfare legislation within Europe.

Development of Sorting System for Fishes by Feed-forward Neural Networks Using Rotation Invariant Features

NASA Astrophysics Data System (ADS)

Shiraishi, Yuhki; Takeda, Fumiaki

In this research, we have developed a sorting system for fishes, which is comprised of a conveyance part, a capturing image part, and a sorting part. In the conveyance part, we have developed an independent conveyance system in order to separate one fish from an intertwined group of fishes. After the image of the separated fish is captured in the capturing part, a rotation invariant feature is extracted using two-dimensional fast Fourier transform, which is the mean value of the power spectrum with the same distance from the origin in the spectrum field. After that, the fishes are classified by three-layered feed-forward neural networks. The experimental results show that the developed system classifies three kinds of fishes captured in various angles with the classification ratio of 98.95% for 1044 captured images of five fishes. The other experimental results show the classification ratio of 90.7% for 300 fishes by 10-fold cross validation method.

7 CFR 1437.303 - Aquaculture, including ornamental fish.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 10 2013-01-01 2013-01-01 false Aquaculture, including ornamental fish. 1437.303... ASSISTANCE PROGRAM Determining Coverage Using Value § 1437.303 Aquaculture, including ornamental fish. (a... human consumption as determined by CCC. (2) Fish raised as feed for other fish that are consumed by...

7 CFR 1437.303 - Aquaculture, including ornamental fish.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 10 2012-01-01 2012-01-01 false Aquaculture, including ornamental fish. 1437.303... ASSISTANCE PROGRAM Determining Coverage Using Value § 1437.303 Aquaculture, including ornamental fish. (a... human consumption as determined by CCC. (2) Fish raised as feed for other fish that are consumed by...

33 CFR 1.07-100 - Summons in lieu of seizure of commercial fishing industry vessels.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Summons in lieu of seizure of... Proceedings § 1.07-100 Summons in lieu of seizure of commercial fishing industry vessels. (a) As used in this... specified in 19 CFR 171.51. (b) When a commercial fishing industry vessel is subject to seizure for a...

50 CFR 665.212 - Non-commercial bag limits.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Non-commercial bag limits. 665.212 Section... Non-commercial bag limits. No more than a total of five fish (all species combined) identified as... any individual participating in a non-commercial vessel-based fishing trip in the MHI management...

Evidence of euryhalinity of the Gulf corvina (Cynoscion othonopterus).

PubMed

Perez-Velazquez, M; Urquidez-Bejarano, P; González-Félix, M L; Minjarez-Osorio, C

2014-01-01

The effects of environmental salinity on physiological responses, growth, and survival of the Gulf corvina, C. othonopterus, were evaluated in a 6-week completely randomized design experiment. Corvina (17.2+/-2.3 g mean initial body weight) were subjected to salinities of 5, 15, 25, and 35 ‰ and fed a commercial feed with protein and lipid contents of 46 and 14 %, respectively. Plasma osmolality increased significantly with salinity, ranging from 335.1+/-5.3 mOsm/kg in fish maintained at 5 ‰, to 354.8+/-6.8 mOsm/kg in fish kept in seawater, while a significant inverse relationship was observed between salinity and moisture content of whole fish, ranging from 73.8+/-0.7 (measured at 5 ‰) to 76.9+/-1.0 % (measured at 35 ‰). In spite of this, growth indices (final weight, weight gain, specific growth rate, condition factor, survival) were not altered, suggesting that, like other members of the family Sciaenidae, the Gulf corvina is a strong osmoregulator. The isosmotic point for this species was estimated to correspond to a salinity of 9.8 ‰. The present study represents the first set of experimental data on salinity tolerance of C. othonopterus and confirms the euryhalinity of this species.

Isolation and in vitro maintenance of trypanosomes from naturally infected and commercially important Brazilian fish.

PubMed

Lemos, Moara; Souto-Padrón, Thaïs

2014-10-01

Fish trypanosomes are widely distributed in commercially important fish, with high prevalence in some Brazilian species. This study provides the first record of the isolation and in vitro maintenance of trypanosomes from Brazilian fish. We produced 49 trypanosome isolates from naturally infected catfish (Hypostomus affinis and Hypostomus luetkeni), using 9 different culture media (out of 31 tested). Trypanosomes were maintained in culture for at least 15 mo and were successfully cryopreserved. Culture forms-epimastigotes and short trypomastigotes-were capable of dividing in vitro. Our study is an important step in the investigation of ultrastructure, taxonomy, and phylogeny of trypanosomes from commercially important Brazilian fish.

Applicability of Perinereis aibuhitensis Grube for fish waste removal from fish cages in Sanggou Bay, P. R. China

NASA Astrophysics Data System (ADS)

Fang, Jinghui; Jiang, Zengjie; Jansen, Henrice M.; Hu, Fawen; Fang, Jianguang; Liu, Yi; Gao, Yaping; Du, Meirong

2017-04-01

The present study investigated the applicability of integrated polychaete-fish culture for fish waste removal to offset negative impact induced by organic benthic enrichment. A field study demonstrated that deposition rate was significantly higher underneath the fish farm than that in control area. The material settling under the farm was characterized by a high amount of fish feces (45%) and uneaten feed (27%). Both feeding rate (FR) and apparent digestibility rate (ADR) increased with decreasing body weight, as was indicated by significantly a higher rate observed for the groups containing smaller individuals in a lab study. The nutrient in fresh deposited material (De) was higher than that in sediments collected under the farm (Se), resulting in lower feces production but higher apparent digestibility rate for the De group as feeding rate was similar. Consequently, higher nutrient removal efficiency was observed in the De group. A mass balance approach indicated that approximately 400-500 individuals m-2 is required for removing all waste materials deposited underneath the fish farm, whereas abundance can be lower (about 300-350 individuals m-2) when only the fish waste needs to be removed. The results showed that a significant amount of waste had been accumulated in the fish cages in Sanggou Bay. The integration of fish with P. aibuhitensis seems promising for preventing organic pollution in the sediment and therefore is an effective strategy for mitigating negative effect of fish farms. Thus such integration can become a new IMTA (integrated multi-trophic aquaculture) model in Sanggou Bay.

Alaska OCS socioeconomic studies program. Technical report number 44. Lower Cook Inlet petroleum development scenarios: commercial fishing industry analysis. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terry, J.M.; Scoles, R.G.; Larson, D.M.

1980-07-01

The objectives of the report are to increase the understanding of the potential relationships between the commercial fishing and Outer Continental Shelf (OCS) petroleum industries and to project the potential impacts on the commercial fishing industry of Cook Inlet and Shelikof Strait that may occur as a result of the proposed OCS Lease Sale Number 60. To meet this objective, the report consists of: (1) the documentation and examination of the history and current trends of the Cook Inlet and Shelikof Strait commercial fishing industry as necessary to develop a basis for projecting fishery development and potential interactions with themore » OCS petroleum industry, (2) the development of models used to forecast the level of commercial fishing industry activity through the year 2000 in the absence of OCS development pursuant to Lease Sale Number 60, and (3) an analysis of the potential impacts of Lease Sale Number 60 based on the hypothesized nature and magnitude of the activities of the commercial fishing and OCS petroleum industries. Both the harvesting and processing sectors of the fishing industry are considered. The sources of impacts considered are the competition for labor, ocean space use, and the infrastructure. Potential impacts due to environmental or biological changes resulting from OCS petroleum development are not considered.« less

Feeding behavior improves prediction of dairy cow voluntary feed intake but cannot serve as the sole indicator.

PubMed

Halachmi, I; Ben Meir, Y; Miron, J; Maltz, E

2016-09-01

Low-cost feeding-behavior sensors will soon be available for commercial use in dairy farms. The aim of this study was to develop a feed intake model for the individual dairy cow that includes feeding behavior. In a research farm, the individual cows' voluntary feed intake and feeding behavior were monitored at every meal. A feed intake model was developed based on data that exist in commercial modern farms: 'BW,' 'milk yield' and 'days in milking' parameters were applied in this study. At the individual cow level, eating velocity seemed to be correlated with feed intake (R 2=0.93 to 0.94). The eating velocity coefficient varied among individuals, ranging from 150 to 230 g/min per cow. The contribution of feeding behavior (0.28) to the dry matter intake (DMI) model was higher than the contribution of BW (0.20), similar to the contribution of fat-corrected milk (FCM)/BW (0.29) and not as large as the contribution of FCM (0.49). Incorporating feeding behavior into the DMI model improved its accuracy by 1.3 (38%) kg/cow per day. The model is ready to be implemented in commercial farms as soon as companies introduce low-cost feeding-behavior sensors on commercial level.

Short-Term Effects of the Anti-sea Lice Therapeutant Emamectin Benzoate on Clam Worms (Nereis virens).

PubMed

McBriarty, G J; Kidd, K A; Burridge, L E

2018-05-01

The polychaete Nereis virens occurs commonly in marine sediments, is widely distributed, and is a popular bait species, as well as a potential replacement for wild-caught fish in commercial fish feed preparations. It is being considered as a potential co-extractive species for culture in integrated multi-trophic aquaculture operations. However, it is not known whether pesticides or drugs used to treat sea lice on farmed salmon, such as emamectin benzoate (EB), would adversely affect cultured or wild worms, because these compounds may persist in the environment. To determine the potential effects of EB to N. virens, bioassays were performed wherein worms were exposed in sand for 30 days to a concentration of 400 µg/kg dw (nominal). While no treatment-related mortality occurred, significant decreases in worm mass and marked behavioral changes (lack of burrowing) were observed in EB-treated sand compared with controls. These lab-based observations suggest a potential hazard to worms at sites where EB treatments have occurred.

Distribution pattern and reduction of polychlorinated biphenyls (PCB) in bluefish fillets through adipose tissue removal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sanders, M.; Haynes, B.L.

1988-11-01

Bluefish, Pomatomus saltatrix, a migratory pelagic species of fish usually travel in large groups of like size along the Atlantic coast. Bluefish of all sizes are caught both commercially and recreationally for human consumption. Owing to its predacious nature, bluefish feed throughout the water column on a large variety of smaller fish and invertebrates. Bluefish bioaccumulate contaminants such as polychlorinated biphenyls (PCB) into various adipose tissues from the water column and through the marine food chain. Two recent reports concluded that PCB concentrations for all except some of the large bluefish caught along the Atlantic coast fell below the limitmore » of 2 ..mu..g/g set by FDA. The purpose of this study was to observe the distribution pattern of PCB in the various edible tissues. Further, it was to determine if the removal of adipose tissues would result in reduced PCB level and therefore decrease PCB exposure to the consumer.« less

Consumption of particulate wastes derived from cage fish farming by aggregated wild fish. An experimental approach.

PubMed

Ballester-Moltó, M; Sanchez-Jerez, P; Aguado-Giménez, F

2017-09-01

Particulate wastes derived from cage fish farming are a trophic resource used by wild fish. This study assesses waste consumption by wild fish and the impact on the final balance of wastes. Consumption was determined according to the difference between the particulate matter exiting the cages and that reaching 5 m away at three different depths, in the presence and absence of wild fish. Wild fish around the experimental cages were counted during feeding and non-feeding periods. A weighted abundance of 1057 fish 1000 m -3 consumed 17.75% of the particulate wastes exiting the cages, on average. Consumption was higher below the cages, where waste outflow was greater. However, waste removal by wild fish was noteworthy along the shallow and deep sides of the cages. Wild fish diminished the net particulate wastes by about 14%, transforming them into more easily dispersible and less harmful wastes. This study demonstrates the mitigating potential of wild fish in reducing environmental impact. Copyright © 2017 Elsevier Ltd. All rights reserved.

Emergence Time and Skin Melanin Spot Patterns Do Not Correlate with Growth Performance, Social Competitive Ability or Stress Response in Farmed Rainbow Trout.

PubMed

Gesto, Manuel; Skov, Peter V; Jokumsen, Alfred

2017-01-01

In wild salmonid fish, specific individual behavioral traits have been correlated with the timing of fry emergence from their gravel spawning nests; Early emerging fish display more aggressive behavior and have a higher probability of becoming socially dominant, compared to fish that emerge at a later stage. Apart from aggression and dominance, other behavioral and metabolic traits, such as boldness, metabolic rate, or growth, have also been linked to emergence time. Altogether, the traits of early- and late-emerging fish resemble those of the proactive and reactive stress-coping style, respectively. As proactive fish are considered more resilient to stress, it may be desirable to select these for aquaculture production. However, it is currently unclear to what extent the link between emergence time and stress-coping styles is maintained in the selective breeding of farmed fish. In the present study, eyed eggs from a commercial supplier were hatched, and larvae fractionated according to their emergence time. Later on, juvenile fish from different emergence fractions were subjected to a stress challenge and also tested to evaluate their competitive ability for food. Beyond some slight dissimilarities in the acute stress responses, emergence fraction displayed no correlation with growth rates, or the ability to compete for feed. Within the whole group of fish utilized in the experiments, no relationship between skin melanin spot pattern and growth performance, stress response intensity, or competitive ability was found. Altogether, the differences in physiological traits related to emergence time were not as strong as those found in earlier studies. It is hypothesized, that the origin and degree of domestication of the fish might be partly responsible for this. The predictive value of skin spots or emergence time to infer the fish stress coping style in farmed fish is also discussed.

Performance and lipid profiles of native chickens fed diet containing skipjack fish oil as by-product of fish canning factory

NASA Astrophysics Data System (ADS)

Leke, J. R.; Mandey, J. S.; Laihad, J. T.; Tinangon, R. M.; Tangkau, L.; Junus, C.

2018-01-01

The study was conducted to determine the use of fish oil as by-product of fish canning factory in diet on the performance and lipid profiles of native chickens. The experiment used 100 native chicken with an average initial body weight of 48,9 gram (sd + 9.9), was used in this study for 8 weeks experiment. These were arranged by a completely randomized design with 5 treatments, 5 replications and 4 hens in replication each. The diets were: R0 = 100% Based Diet (BD) + 0% Fish Oil (FO); R1 = 98.5% BD + 1.5% FO; R2 = 98% BD + 2% FO; R3 = 97.5% BD + 2.5% FO; R4 = 97 % BD + 3% FO. Feed and water were provided ad libitum. Variables were performance parameters and lipid profiles. Results showed that fish oil inclusion in diets were significantly increased feed intake, body weight gain, carcass percentage, liver, breast and thigh weight, and decreased blood cholesterol, carbohydrate and meat cholesterol, and also tended to decrease abdominal fat. However, there were no affected on feed conversion, water, protein, fat and ash of breast meat. It can be concluded that the use of fish oil in diet up to 3% could improved performance parameters of native chickens.

Formulation of a fish feed for goldfish with natural astaxanthin extracted from shrimp waste.

PubMed

Weeratunge, W K O V; Perera, B G K

2016-01-01

Astaxanthin is a xanthophyll carotenoid, which exhibits many important biological activities including a high degree of antioxidant capacity (AOC) and antibacterial activity, hence has a significant applicability in food, pharmaceutical and cosmetic industries. An attempt was made towards optimization of astaxanthin extraction conditions using three different extraction conditions and a solvent series, from uncooked, cooked and acid-treated shrimp waste, which is a readily available and cheap source of the pigment. The astaxanthin extracts were analyzed by comparing their UV-visible absorbance spectra and thin layer chromatograms with a standard astaxanthin sample. The percentage of astaxanthin in each crude sample was determined using the Beer-Lambert law. The Folin-Ciocalteu assay and the disk diffusion assay were used to investigate the antioxidant capacities and antibacterial activities of extracted astaxanthin samples respectively. The extracted astaxanthin was incorporated into fish feeds to test its ability to enhance the skin color of goldfish. The best astaxanthin percentage of 68 % was observed with the acetone:ethyl acetate (1:1) solvent system facilitated by maceration of cooked and acid treated shrimp, whereas the best crude yield of 33 % was found to be in the acetone extract of the acid-treated shrimp sample. The highest AOC of 65 µg pyrogallol equivalents/mg was observed for the EtOAc extract obtained by maceration of acid-treated shrimp waste. The highest AOC by sonication and soxhlet extraction methods were also obtained with the EtOAc solvent. The extracts exhibited antibacterial activity against four selected bacterial strains. The newly formulated astaxanthin enriched fish feed was economical and indicated a significant improvement of the skin color and healthiness of goldfish compared to the control feeds. Biologically active astaxanthin can be successfully extracted from shrimp waste in higher percentages. The extraction technique and the solvent used to extract astaxanthin from shrimp waste should be decided depending on the desired outcome and application of astaxanthin. Moreover, the novel astaxanthin enriched fish feed formulated during this study was found to effectively enhance the skin color of goldfish within 10 days, a much shorter feeding period compared to previously reported feeding periods in similar studies.Graphical abstractFormulation of a skin color enhancing fish feed for ornamental fish using crude astaxanthin extracted from shrimp waste.

Intake of farmed Atlantic salmon fed soybean oil increases hepatic levels of arachidonic acid-derived oxylipins and ceramides in mice

USDA-ARS?s Scientific Manuscript database

Introduction of vegetable ingredients in fish feed has affected the fatty acid composition in farmed Atlantic salmon (Salmo salar L). Here we investigated how changes in fish feed affected the metabolism of mice fed diets containing fillets from such farmed salmon. We demonstrate that replacement of...

Effect of fasting on body composition and responses to stress in sunshine bass

USDA-ARS?s Scientific Manuscript database

Technical Abstract The integrated responses of the hormonal regulation of growth and stress in sunshine bass as regulated by feed deprivation were investigated. Groups of fish were fed 1.5% of the body weight per day or offered no feed for 4 weeks. Another group of fish was not fed for 3 weeks ...

Effect of strain and diet on growth performance characteristics and relative expression of genes coding for electron transport chain in channel catfish

USDA-ARS?s Scientific Manuscript database

The major cost in aquaculture production systems is feed, and the use of biotechnology approaches to identify fishes with superior feed efficiency (FE) may have a positive influence on profitability. There been little use of genetically based technologies to assess FE in culture fishes. Mitochondria...

Combined effects of Chinese medicine feed and ginger extract bath on co-infection of Ichthyophthirius multifiliis and Dactylogyrus ctenopharyngodonid in grass carp

USDA-ARS?s Scientific Manuscript database

Dactylogyrus ctenopharyngodonid and Ichthyophthirius multifiliis are two important ectoparasites of freshwater fish. Co-infection by the two parasites leads to high fish mortality and results in heavy economic losses. This study aimed to evaluate the efficacy of medicated feed and a ginger extract b...

Viewpoints of high migratory tuna species ecology. Comment on ;Physics of metabolic organization; by M. Jusup et al.

NASA Astrophysics Data System (ADS)

Kitagawa, Takashi; Aoki, Yoshinori

2017-03-01

When discussing the evolution of fish migration, it is necessary to consider the total benefit fish acquire over their entire life history. With diadromous migration, for instance, some fish species migrate from freshwater and feed in the ocean (anadromous species), and others migrate from the ocean and feed in freshwater (catadromous). These contrasting directions of migration can largely be explained by the relative availability of food resources in ocean and freshwater habitats [1]. However, there are few examples that measure or quantify total energy as a concrete value that a single fish acquires through migration.

Restoration of fillet n-3 long-chain polyunsaturated fatty acid is improved by a modified fish oil finishing diet strategy for atlantic salmon (Salmo salar L.) smolts fed palm fatty acid distillate.

PubMed

Codabaccus, Mohamed B; Bridle, Andrew R; Nichols, Peter D; Carter, Chris G

2012-01-11

Reducing the lipid content in fish prior to feeding a fish oil finishing diet (FOFD) has the potential to improve n-3 long-chain (≥ C(20)) polyunsaturated fatty acid (LC-PUFA) restoration. This study had two main objectives: (1) determine whether feeding Atlantic salmon smolt a 75% palm fatty acid distillate diet (75PFAD) improves the apparent digestibility (AD) of saturated fatty acids (SFA) and (2) examine whether a food deprivation period after growth on 75PFAD leads to higher n-3 LC-PUFA restoration in the fillet when applying a FOFD. The AD of SFA was higher for 75PFAD compared to that of a fish oil (FO) diet. The relative level (as % total fatty acids (FA)) of n-3 LC-PUFA was higher in unfed fish compared to that in continuously fed fish after 21 and 28 day FOFD periods, respectively. Our results suggest that a food deprivation period prior to feeding a FOFD improves the efficiency of n-3 LC-PUFA restoration in the fillet of Atlantic salmon smolt.

Central control of cardiorespiratory interactions in fish.

PubMed

Taylor, Edwin W; Leite, Cleo A C; Levings, Jennifer J

2009-01-01

Fish control the relative flow rates of water and blood over the gills in order to optimise respiratory gas exchange. As both flows are markedly pulsatile, close beat-to-beat relationships can be predicted. Cardiorespiratory interactions in fish are controlled primarily by activity in the parasympathetic nervous system that has its origin in cardiac vagal preganglionic neurons. Recordings of efferent activity in the cardiac vagus include units firing in respiration-related bursts. Bursts of electrical stimuli delivered peripherally to the cardiac vagus or centrally to respiratory branches of cranial nerves can recruit the heart over a range of frequencies. So, phasic, efferent activity in cardiac vagi, that in the intact fish are respiration-related, can cause heart rate to be modulated by the respiratory rhythm. In elasmobranch fishes this phasic activity seems to arise primarily from central feed-forward interactions with respiratory motor neurones that have overlapping distributions with cardiac neurons in the brainstem. In teleost fish, they arise from increased levels of efferent vagal activity arising from reflex stimulation of chemoreceptors and mechanoreceptors in the orobranchial cavity. However, these differences are largely a matter of emphasis as both groups show elements of feed-forward and feed-back control of cardiorespiratory interactions.

Between-Habitat Variation of Benthic Cover, Reef Fish Assemblage and Feeding Pressure on the Benthos at the Only Atoll in South Atlantic: Rocas Atoll, NE Brazil

PubMed Central

Longo, G. O.; Morais, R. A.; Martins, C. D. L.; Mendes, T. C.; Aued, A. W.; Cândido, D. V.; de Oliveira, J. C.; Nunes, L. T.; Fontoura, L.; Sissini, M. N.; Teschima, M. M.; Silva, M. B.; Ramlov, F.; Gouvea, L. P.; Ferreira, C. E. L.; Segal, B.; Horta, P. A.; Floeter, S. R.

2015-01-01

The Southwestern Atlantic harbors unique and relatively understudied reef systems, including the only atoll in South Atlantic: Rocas atoll. Located 230 km off the NE Brazilian coast, Rocas is formed by coralline red algae and vermetid mollusks, and is potentially one of the most “pristine” areas in Southwestern Atlantic. We provide the first comprehensive and integrative description of the fish and benthic communities inhabiting different shallow reef habitats of Rocas. We studied two contrasting tide pool habitats: open pools, which communicate with the open ocean even during low tides, thus more exposed to wave action; and closed pools, which remain isolated during low tide and are comparatively less exposed. Reef fish assemblages, benthic cover, algal turfs and fish feeding pressure on the benthos remarkably varied between open and closed pools. The planktivore Thalassoma noronhanum was the most abundant fish species in both habitats. In terms of biomass, the lemon shark Negaprion brevirostris and the omnivore Melichtys niger were dominant in open pools, while herbivorous fishes (mainly Acanthurus spp.) prevailed in closed pools. Overall benthic cover was dominated by algal turfs, composed of articulated calcareous algae in open pools and non-calcified algae in closed pools. Feeding pressure was dominated by acanthurids and was 10-fold lower in open pools than in closed pools. Besides different wave exposure conditions, such pattern could also be related to the presence of sharks in open pools, prompting herbivorous fish to feed more in closed pools. This might indirectly affect the structure of reef fish assemblages and benthic communities. The macroalgae Digenea simplex, which is uncommon in closed pools and abundant in the reef flat, was highly preferred in herbivory assays, indicating that herbivory by fishes might be shaping this distribution pattern. The variations in benthic and reef fish communities, and feeding pressure on the benthos between open and closed pools suggest that the dynamics in open pools is mostly driven by physical factors and the tolerance of organisms to harsh conditions, while in closed pools direct and indirect effects of species interactions also play an important role. Understanding the mechanisms shaping biological communities and how they scale-up to ecosystem functioning is particularly important on isolated near-pristine systems where natural processes can still be studied under limited human impact. PMID:26061735

Between-Habitat Variation of Benthic Cover, Reef Fish Assemblage and Feeding Pressure on the Benthos at the Only Atoll in South Atlantic: Rocas Atoll, NE Brazil.

PubMed

Longo, G O; Morais, R A; Martins, C D L; Mendes, T C; Aued, A W; Cândido, D V; de Oliveira, J C; Nunes, L T; Fontoura, L; Sissini, M N; Teschima, M M; Silva, M B; Ramlov, F; Gouvea, L P; Ferreira, C E L; Segal, B; Horta, P A; Floeter, S R

2015-01-01

The Southwestern Atlantic harbors unique and relatively understudied reef systems, including the only atoll in South Atlantic: Rocas atoll. Located 230 km off the NE Brazilian coast, Rocas is formed by coralline red algae and vermetid mollusks, and is potentially one of the most "pristine" areas in Southwestern Atlantic. We provide the first comprehensive and integrative description of the fish and benthic communities inhabiting different shallow reef habitats of Rocas. We studied two contrasting tide pool habitats: open pools, which communicate with the open ocean even during low tides, thus more exposed to wave action; and closed pools, which remain isolated during low tide and are comparatively less exposed. Reef fish assemblages, benthic cover, algal turfs and fish feeding pressure on the benthos remarkably varied between open and closed pools. The planktivore Thalassoma noronhanum was the most abundant fish species in both habitats. In terms of biomass, the lemon shark Negaprion brevirostris and the omnivore Melichtys niger were dominant in open pools, while herbivorous fishes (mainly Acanthurus spp.) prevailed in closed pools. Overall benthic cover was dominated by algal turfs, composed of articulated calcareous algae in open pools and non-calcified algae in closed pools. Feeding pressure was dominated by acanthurids and was 10-fold lower in open pools than in closed pools. Besides different wave exposure conditions, such pattern could also be related to the presence of sharks in open pools, prompting herbivorous fish to feed more in closed pools. This might indirectly affect the structure of reef fish assemblages and benthic communities. The macroalgae Digenea simplex, which is uncommon in closed pools and abundant in the reef flat, was highly preferred in herbivory assays, indicating that herbivory by fishes might be shaping this distribution pattern. The variations in benthic and reef fish communities, and feeding pressure on the benthos between open and closed pools suggest that the dynamics in open pools is mostly driven by physical factors and the tolerance of organisms to harsh conditions, while in closed pools direct and indirect effects of species interactions also play an important role. Understanding the mechanisms shaping biological communities and how they scale-up to ecosystem functioning is particularly important on isolated near-pristine systems where natural processes can still be studied under limited human impact.

Effects of chronic dietary exposure of zinc oxide nanoparticles on the serum protein profile of juvenile common carp (Cyprinus carpio L.).

PubMed

Chupani, Latifeh; Zusková, Eliška; Niksirat, Hamid; Panáček, Aleš; Lünsmann, Vanessa; Haange, Sven-Bastiaan; von Bergen, Martin; Jehmlich, Nico

2017-02-01

Zinc oxide (ZnO) nanoparticles (NPs) have been dramatically used in industry, biology, and medicine. Despite their interesting physico-chemical properties for application in various industrial, medical, and consumer products, safe use of ZnO NPs are under challenges due to the inadequate information related to their toxicological endpoints. Proteomics was applied to evaluate the sub-lethal effects of dietary exposure to ZnO NPs on serum proteome profile of juvenile common carp, (Cyprinus carpio). Therefore, ZnO NPs solution (500mgkg -1 of feed) was added to a commercial carp feed for six weeks. We compared the serum proteome profile from 7 controls and 7 treated fish. In addition, zinc accumulation were measured in intestine, liver, gill and brain. In total, we were able to identify 326 proteins from 6845 distinct peptides. As a result of the data analysis, the abundance levels of four proteins were significantly altered (fold change (fc) ≥2 and p<0.05) after dietary exposure to ZnO NPs. The protein levels of the complement component C4-2 (fc 2.5) and the uncharacterised protein encoded by kng1 (fc 5.8) were increased and major histocompatibility class I (fc 4.9) and the uncharacterised protein encoded by lum (fc 3.5) were decreased (fc 2.5). Molecular pathway analysis revealed four canonical pathways including acute-phase response signalling, liver and retinoid X receptors activation, and intrinsic and extrinsic prothrombin activation pathways as significantly regulated in the treated fish. No significant difference was observed for zinc accumulation in exposed fish compared to controls. In summary, despite no apparent accumulation, ZnO NPs exposure to common carp probably disturbs the fish homeostasis by affecting proteins of the haematological and the immune systems. Copyright © 2016 Elsevier B.V. All rights reserved.

Isotope niche dimension and trophic overlap between bigheaded carps and native filter-feeding fish in the lower Missouri River, USA

USGS Publications Warehouse

Wang, Jianzhu; Chapman, Duane C.; Xu, Jun; Wang, Yang; Gu, Binhe

2018-01-01

Stable carbon and nitrogen isotope values (δ13C and δ15N) were used to evaluate trophic niche overlap between two filter-feeding fishes (known together as bigheaded carp) native to China, silver carp (Hypophthalmichthys molitrix) and bighead carp (Hypophthalmichthys nobilis), and three native filter-feeding fish including bigmouth buffalo (Ictiobus cyprinellus), gizzard shad (Dorosoma cepedianum) and paddlefish (Polyodon spathula) in the lower Missouri River, USA, using the Bayesian Stable Isotope in R statistics. Results indicate that except for bigmouth buffalo, all species displayed similar trophic niche size and trophic diversity. Bigmouth buffalo occupied a small trophic niche and had the greatest trophic overlap with silver carp (93.6%) and bighead carp (94.1%) followed by gizzard shad (91.0%). Paddlefish had a trophic niche which relied on some resources different from those used by other species, and therefore had the lowest trophic overlap with bigheaded carp and other two native fish. The trophic overlap by bigheaded carp onto native fish was typically stronger than the reverse effects from native fish. Average niche overlap between silver carp and native species was as high as 71%, greater than niche overlap between bighead carp and native fish (64%). Our findings indicate that bigheaded carps are a potential threat to a diverse and stable native fish community.

Does small-scale vertical distribution of juvenile schooling fish affect prey availability to surface-feeding seabirds in the Wadden Sea?

NASA Astrophysics Data System (ADS)

Dänhardt, Andreas; Becker, Peter H.

2011-02-01

Food availability is a key variable influencing breeding performance and demography of marine top predators. Due to methodological problems, proportionality between fish abundance and availability is often assumed without being explicitly tested. More specifically, better breeding performance of surface-feeding seabirds at times of large prey stocks suggests that prey availability is also a function of prey abundance. Using vertically resolved stow net sampling we tested whether local abundance and length composition of pelagic fish are reliable predictors of the availability of these fish to surface-feeding Common Terns ( Sterna hirundo) breeding in the German Wadden Sea. Prey fish were found to concentrate below the maximum diving depth of the terns. Individuals caught close to the surface were in most cases smaller than conspecifics caught at greater depth. Correlations between fish abundance within and out of reach of the terns appeared to be both species- and site-specific rather than driven by overall fish abundance. Vertical distribution patterns of the terns' main prey fish could be explained as anti-predator behavior, reducing prey availability to the terns. In 2007, when breeding performance was much better than in 2006, herring and whiting were much more abundant, suggesting that overall prey abundance may also increase prey availability in habitats other than those represented by the stow net sampling.

Dietary Aloe vera improves plasma lipid profile, antioxidant, and hepatoprotective enzyme activities in GIFT-tilapia (Oreochromis niloticus) after Streptococcus iniae challenge.

PubMed

Gabriel, Ndakalimwe Naftal; Qiang, Jun; Ma, Xin Yu; He, Jie; Xu, Pao; Liu, Kai

2015-10-01

The current study investigated the effects of dietary Aloe vera on plasma lipid profile status, antioxidant, and hepatoprotective enzyme activities of GIFT-tilapia juveniles under Streptococcus iniae challenge. Five dietary groups were designed including a control and 100 % Aloe powder incorporated into a tilapia feed at 0.5, 1, 2, and 4 %/kg feed, which were administered for 8 weeks. Fish fed dietary Aloe at 4 %/kg feed significantly reduced in total cholesterol, while triacylglycerol reduced (P < 0.05) in those fed 0.5, 2, and 4 % Aloe/kg feed compared to unsupplemented ones. High-density lipoprotein was significantly elevated in fish fed 0.5 and 1 % Aloe/kg feed compared to unsupplemented ones, and no significant changes (P > 0.05) were noted in low-density lipoprotein among test groups. Furthermore, high activities of superoxide dismutase, catalase, and glutathione peroxide in liver tissues were observed in Aloe-supplemented fish compared to unsupplemented ones, before and after S. iniae challenge (7.7 × 10(6) CFU cells/mL). Variations were also noted in malondialdehyde activity throughout the trial, but no significant difference (P > 0.05) was observed between groups. Meanwhile, Aloe-supplemented fish reduced serum aspartate and alanine aminotransferase (AST and ALT) activities before and after challenge. Based on the second-order polynomial regression analysis, dietary Aloe inclusion levels less than or equal to 1.88, 1.86, and 2.79 %/kg feed were determined to be suitable in improving plasma lipid profile status, antioxidant, and hepatoprotective enzyme activities in GIFT-tilapia in this study, respectively. Thus, A. vera extracts may be recommended as a tilapia feed supplement to enhance fish antioxidant and hepatoprotective capacities, especially during disease outbreaks.

The influence of microplastics and halogenated contaminants in feed on toxicokinetics and gene expression in European seabass (Dicentrarchus labrax).

PubMed

Granby, Kit; Rainieri, Sandra; Rasmussen, Rie Romme; Kotterman, Michiel J J; Sloth, Jens Jørgen; Cederberg, Tommy Licht; Barranco, Alex; Marques, António; Larsen, Bodil Katrine

2018-07-01

When microplastics pollute fish habitats, it may be ingested by fish, thereby contaminating fish with sorbed contaminants. The present study investigates how combinations of halogenated contaminants and microplastics associated with feed are able to alter toxicokinetics in European seabass and affect the fish. Microplastic particles (2%) were added to the feed either with sorbed contaminants or as a mixture of clean microplastics and chemical contaminants, and compared to feed containing contaminants without microplastics. For the contaminated microplastic diet, the accumulation of polychlorinated biphenyls (PCBs) and brominated flame retardants (BFRs) in fish was significantly higher, increasing up to 40 days of accumulation and then reversing to values comparable to the other diets at the end of accumulation. The significant gene expression results of liver (cyp1a, il1β, gstα) after 40 days of exposure indicate that microplastics might indeed exacerbate the toxic effects (liver metabolism, immune system, oxidative stress) of some chemical contaminants sorbed to microplastics. Seabass quickly metabolised BDE99 to BDE47 by debromination, probably mediated by deiodinase enzymes, and unlike other contaminants, this metabolism was unaffected by the presence of microplastics. For the other PCBs and BFRs, the elimination coefficients were significantly lower in fish fed the diet with contaminants sorbed to microplastic compared to the other diets. The results indicate that microplastics affects liver detoxification and lipid distribution, both of which affect the concentration of contaminants. Copyright © 2018 Elsevier Inc. All rights reserved.

Novel insights into iron regulation and requirement in marine medaka Oryzias melastigma

NASA Astrophysics Data System (ADS)

Wang, Jian; Wang, Wen-Xiong

2016-05-01

Iron (Fe) is an essential trace element for marine fish. However, our knowledge of Fe requirements at different development stages of marine fish is still limited. Here, we reported the efficient Fe absorption strategies adopted by larval fish under different dietary Fe supplementary levels (i.e., 0-640 mg/kg). Biokinetically, the larval fish controlled their dietary Fe assimilation efficiency (AE, 1.6-18.5%), and enhanced their waterborne Fe uptake (ca. 2.5 fold change of uptake rate constant) once the dietary Fe was deficient (i.e., 27.4 mg Fe/kg feed). Transcriptionally, the expression of hepcidin1 (hep1; Fe regulator; i.e., 2.3-15.7 fold change) in larval fish was positively correlated with the Fe supplementary levels. Comparatively, the female adult fish were poor in assimilating the added Fe source (i.e., ferric form) with similar life-sustainable levels of Fe (i.e., 0.046-0.12 μg/g/d assimilated for Fe supplementary levels of 27.4, 162 and 657 mg Fe/kg feed). The overall feeding experiments suggested that dietary net Fe flux sufficient for the normal growth of larval medaka was 0.71-1.75 μg/g/d (i.e., 83.9 mg Fe/kg feed), consistent with the modeled value (i.e., 1.09-2.16 μg/g/d). In female adults, the estimated essential net Fe flux was 0.88-0.90 μg/g/d.

Diastereoisomer- and enantiomer-specific determination of hexabromocyclododecane in fish oil for food and feed.

PubMed

Ortiz, Xavier; Guerra, Paula; Díaz-Ferrero, Jordi; Eljarrat, Ethel; Barceló, Damià

2011-01-01

Fish oils are one of the main sources of ω-3 fatty acids. However, they can present elevated levels of some lipophilic pollutants, such as hexabromocyclododecanes (HBCDs). Since data about HBCDs in fish oil samples are very limited, in this study, 25 samples of fish oil for feed and food have been analyzed. Total HBCDs, as well as, α-, β- and γ-diastereoisomers have been determined. Total HBCDs ranged from 0.09 to 26.8ngg(-1), with higher concentrations in fish oil for feed (average value of 9.69ngg(-1)) than those for food (1.14ngg(-1)). Concentrations of α-HBCD (average value of 4.12ngg(-1) in feed samples and 0.48ngg(-1) in food samples) and γ-HBCD (5.05 and 0.43ngg(-1) respectively) were higher than that of β-HBCD (0.52 and 0.19ngg(-1) respectively) in most of the samples. However, none of them was predominant in the samples. Concentrations of HBCDs were compared to concentrations of other pollutants and correlation between dioxin and dioxin-like PCBs levels and HBCDs levels were observed. Intake of HBCDs was calculated for fish oil with human consumption purposes and it ranged from 0.08 to 5.38ng HBCDsd(-1), which could contribute significantly to HBCDs total intake. Enantiomeric fractions were also determined. No clear enrichment was observed for γ-HBCD, while (-)-α-HBCD enrichment was detected in some samples. Copyright © 2010 Elsevier Ltd. All rights reserved.

40 CFR 63.11627 - What definitions apply to this subpart?

Code of Federal Regulations, 2010 CFR

2010-07-01

... feed supplements; prepared animal feeds; specialty animal (e.g., guinea pig, mice, mink) feeds; fish... the purposes of this subpart. Average daily feed production level means the average amount of animal... feed production level is based on the one-year period prior to the compliance date for existing sources...

Feeding ecology underlies the evolution of cichlid jaw mobility.

PubMed

Martinez, Christopher M; McGee, Matthew D; Borstein, Samuel R; Wainwright, Peter C

2018-06-19

The fish feeding apparatus is among the most diverse functional systems in vertebrates. While morphological and mechanical variation of feeding systems are well studied, we know far less about the diversity of the motions that they produce. We explored patterns of feeding movements in African cichlids from Lakes Malawi and Tanganyika, asking whether the degree of kinesis is associated with dietary habits of species. We used geometric morphometrics to measure feeding kinesis as trajectories of shape change, based on 326 high-speed videos in 56 species. Cranial morphology was significantly related to feeding movements, both of which were distributed along a dietary axis associated with prey evasiveness. Small-mouthed cichlids that feed by scraping algae and detritus from rocks had low kinesis strikes, while large-mouthed species that eat large, evasive prey (fishes and shrimps) generated the greatest kinesis. Despite having higher overall kinesis, comparisons of trajectory shape (linearity) revealed that cichlids that eat mobile prey also displayed more kinematically conserved, or efficient, feeding motions. Our work indicates that prey evasiveness is strongly related to the evolution of cichlid jaw mobility, suggesting that this same relationship may explain the origins and diversity of highly kinetic jaws that characterize the super-radiation of spiny-rayed fishes. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Encountering a bait is necessary but insufficient to explain individual variability in vulnerability to angling in two freshwater benthivorous fish in the wild

PubMed Central

Monk, Christopher Thomas; Arlinghaus, Robert

2017-01-01

Fish personality traits, such as swimming activity, or personality related emergent behavioural properties, such as the degree of space use shown by an individual fish, should affect encounter rates between individual fish and fishing gear. Increased encounters should in turn drive vulnerability to capture by passively operated gears. However, empirical evidence documenting a relationship between activity-based behaviours and vulnerability to capture by passive fishing gear in the wild is limited. Using whole-lake acoustic telemetry, we first documented significant repeatabilities over several months in a suite of encounter rate-associated behaviours (swimming distance, activity space size, time on baited feeding sites, switching frequency among baited feeding sites, distance to the lake bottom) in two recreationally important benthivorous cyprinid species, the common carp (Cyprinus carpio) and tench (Tinca tinca). We then experimentally targeted both species using stationary angling on baited feeding sites. Individual fish regularly visited the angling sites, documenting that the fishes encountered the angling baits. When attempting to explain individual variation in vulnerability as a function of repeatable behavioural traits, we found no evidence of a significant relationship among various encounter-based behaviours and vulnerability to angling for both species. There was also no evidence for size selection or for energetically less conditioned fish to be more vulnerable. The data cumulatively suggest that fine-scale behaviours after encountering a bait (e.g., frequency of bait intake) may be ultimately decisive for determining vulnerability to angling in benthivorous fish. Based on our work, fishing-induced selection on encounter-based behaviours in recreational angling for benthivorous fish in the wild appears unlikely. PMID:28301558

Preventing commercial fishing deaths in Alaska

PubMed Central

Lincoln, J. M.; Conway, G. A.

1999-01-01

OBJECTIVES: To evaluate the effectiveness of the United States Commercial Fishing Industry Vessel Safety Act of 1988 in reducing the high occupational death rate (200/100,000/year in 1991-2) among Alaska's commercial fishermen. METHODS: Comprehensive surveillance of deaths in commercial fishing was established by our office during 1991 and 1992 for Alaska. Demographic data and data on risk factors and incidents were compiled and analysed for trend. RESULTS: During 1991-8, there was a significant (p < 0.001) decrease in deaths in Alaska related to commercial fishing. Although drownings from fishermen falling overboard and events related to crab fishing vessels (often conducted far offshore and in winter) have continued to occur, marked progress (significant downward trend, p < 0.001) has been made in saving the lives of people involved in vessels capsizing and sinking. CONCLUSIONS: Specific measures tailored to prevent drowning associated with vessels capsizing and sinking in Alaska's commercial fishing industry have been successful. However, these events continue to occur, and place fishermen and rescue personnel at substantial risk. Additional strategies must be identified to reduce the frequency of vessels capsizing and sinking, to enable parallel improvements in the mortality among crab fishermen, and to prevent fishermen falling overboard and drownings associated with them.   PMID:10658549

Energy profiling of demersal fish: a case-study in wind farm artificial reefs.

PubMed

De Troch, Marleen; Reubens, Jan T; Heirman, Elke; Degraer, Steven; Vincx, Magda

2013-12-01

The construction of wind farms introduces artificial hard substrates in sandy sediments. As Atlantic cod (Gadus morhua) and pouting (Trisopterus luscus) tend to aggregate in order to feed around these reefs, energy profiling and trophic markers were applied to study their feeding ecology in a wind farm in the Belgian part of the North Sea. The proximate composition (carbohydrates, proteins and lipids) differed significantly between liver and muscle tissue but not between fish species or between their potential prey species. Atlantic cod showed to consume more energy than pouting. The latter had a higher overall energy reserve and can theoretically survive twice as long on the available energy than cod. In autumn, both fish species could survive longer on their energy than in spring. Polyunsaturated fatty acids were found in high concentrations in fish liver. The prey species Jassa and Pisidia were both rich in EPA while Jassa had a higher DHA content than Pisidia. Energy profiling supported the statement that wind farm artificial reefs are suitable feeding ground for both fish species. Sufficient energy levels were recorded and there is no indication of competition.

Hiding and feeding in floating seaweed: Floating seaweed clumps as possible refuges or feeding grounds for fishes

NASA Astrophysics Data System (ADS)

Vandendriessche, Sofie; Messiaen, Marlies; O'Flynn, Sarah; Vincx, Magda; Degraer, Steven

2007-02-01

Floating seaweed is considered to be an important habitat for juvenile fishes due to the provision of food, shelter, a visual orientation point and passive transport. The importance of the presence of the highly dynamical seaweed clumps from the North Sea to juvenile neustonic fishes was investigated by analysing both neuston samples (without seaweed) and seaweed samples concerning fish community structure, and length-frequency distributions and feeding habits of five associated fish species. While the neustonic fish community was mainly seasonally structured, the seaweed-associated fish community was more complex: the response of the associated fish species to environmental variables was species specific and probably influenced by species interactions, resulting in a large multivariate distance between the samples dominated by Chelon labrosus and the samples dominated by Cyclopterus lumpus, Trachurus trachurus and Ciliata mustela. The results of the stomach analysis confirmed that C. lumpus is a weedpatch specialist that has a close spatial affinity with the seaweed and feeds intensively on the seaweed-associated invertebrate fauna. Similarly, C. mustela juveniles also fed on the seaweed fauna, but in a more opportunistic way. The shape of the size-frequency distribution suggested enhanced growth when associated with floating seaweed. Chelon labrosus and T. trachurus juveniles were generally large in seaweed samples, but large individuals were also encountered in the neuston. The proportion of associated invertebrate fauna in their diet was of minor importance, compared to the proportions in C. lumpus. Individuals of Syngnathus rostellatus mainly fed on planktonic invertebrates but had a discontinuous size-frequency distribution, suggesting that some of the syngnathids were carried with the seaweed upon detachment and stayed associated. Floating seaweeds can therefore be regarded as ephemeral habitats shared between several fish species (mainly juveniles) that use them for different reasons and with varying intensity.

Turbulence, Temperature, and Turbidity: The Ecomechanics of Predator-Prey Interactions in Fishes.

PubMed

Higham, Timothy E; Stewart, William J; Wainwright, Peter C

2015-07-01

Successful feeding and escape behaviors in fishes emerge from precise integration of locomotion and feeding movements. Fishes inhabit a wide range of habitats, including still ponds, turbulent rivers, and wave-pounded shorelines, and these habitats vary in several physical variables that can strongly impact both predator and prey. Temperature, the conditions of ambient flow, and light regimes all have the potential to affect predator-prey encounters, yet the integration of these factors into our understanding of fish biomechanics is presently limited. We explore existing knowledge of kinematics, muscle function, hydrodynamics, and evolutionary morphology in order to generate a framework for understanding the ecomechanics of predator-prey encounters in fishes. We expect that, in the absence of behavioral compensation, a decrease in temperature below the optimum value will reduce the muscle power available both to predator and prey, thus compromising locomotor performance, suction-feeding mechanics of predators, and the escape responses of prey. Ambient flow, particularly turbulent flow, will also challenge predator and prey, perhaps resulting in faster attacks by predators to minimize mechanical instability, and a reduced responsiveness of prey to predator-generated flow. Reductions in visibility, caused by depth, turbidity, or diel fluctuations in light, will decrease distances at which either predator or prey detect each other, and generally place a greater emphasis on the role of mechanoreception both for predator and prey. We expect attack distances to be shortened when visibility is low. Ultimately, the variation in abiotic features of a fish's environment will affect locomotion and feeding performance of predators, and the ability of the prey to escape. The nature of these effects and how they impact predator-prey encounters stands as a major challenge for future students of the biomechanics of fish during feeding. Just as fishes show adaptations for capturing specific types of prey, we anticipate they are also adapted to the physical features of their preferred habitat and show a myriad of behavioral mechanisms for dealing with abiotic factors during predator-prey encounters. © The Author 2015. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

[Feeding ecology of Conger myriaster and structure of the food webs in artificial reef zone, Laoshan Bay, China].

PubMed

Liu, Hong Yan; Sun, Tong Tong; Zeng, Xiao Qi; Zhang, Pei Dong; Li, Wen Tao; Zhang, Xiu Mei

2018-04-01

Based on cage net and longline fishing surveys in Laoshan Bay, China, from April 2015 to January 2017, a total of 279 Conger myriaster stomach samples were analyzed to study their feeding ecology, including diet composition, feeding type, feeding grade, feeding intensity, trophic niche, and trophic level. The stomach content analysis of nine key fish species (including Sebastes schlegelii, Hexagrammos otakii, Hexagrammos agrammus, Sebastiscus mamoratus, Lateolabrax maculatus, etc.), were conducted to examine the food webs in artificial reef zone. The results showed that the diet of C. myriaster consisted of more than 30 species belonging to seven orders, in which shrimps were the most dominant prey species, followed by fishes and cephalopods. The dominant species in the diet of C. myriaster were H.otakii, Enedrias fangi, Trachypenaeus curvirostris, Ammodytes personatus and Alpheus japonicas. The diet composition of C. myriaster varied with season and anal length. Fishes and shrimps were the two important groups throughout the years. Cephalopods were predominant in spring. Cephalopods and crabs were predominant in Autumn. Fish eggs were eaten mostly during winter. Fish eggs and T. curvirostris were the dominant prey groups of the C. myriaster with anal length ≤120 mm, whereas A. personatus and A. japonicas were the dominant prey groups of the C. myriaster with anal length 120-130 mm, H.otakii and E.fangi were the dominant prey of the C. myriaster with anal length ＞130 mm. The percentage of empty stomach of C. myriaster varied significantly with season, but the mean stomach fullness index did not. The percentage of empty stomach and mean stomach fullness index did not differ significantly among different anal length groups. The trophic levels of the key fish species were higher than level 3, with C. myriaster at the top of food webs (with a trophic level of 4.636). Decapoda, crabs, amphipoda and molluscs were the main prey of key fish species, while Crustaceans, E. fangi, H. otakii and A. personatus were the main preys of L. maculatus and C. myriaster.

50 CFR 660.75 - Essential Fish Habitat (EFH).

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 13 2012-10-01 2012-10-01 false Essential Fish Habitat (EFH). 660.75... Groundfish Fisheries § 660.75 Essential Fish Habitat (EFH). Essential fish habitat (EFH) is defined as those waters and substrate necessary to fish for spawning, breeding, feeding or growth to maturity (16 U.S.C...

50 CFR 660.75 - Essential Fish Habitat (EFH).

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Essential Fish Habitat (EFH). 660.75... Groundfish Fisheries § 660.75 Essential Fish Habitat (EFH). Essential fish habitat (EFH) is defined as those waters and substrate necessary to fish for spawning, breeding, feeding or growth to maturity (16 U.S.C...

50 CFR 660.75 - Essential Fish Habitat (EFH).

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Essential Fish Habitat (EFH). 660.75... Groundfish Fisheries § 660.75 Essential Fish Habitat (EFH). Essential fish habitat (EFH) is defined as those waters and substrate necessary to fish for spawning, breeding, feeding or growth to maturity (16 U.S.C...

50 CFR 660.75 - Essential Fish Habitat (EFH).

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 13 2013-10-01 2013-10-01 false Essential Fish Habitat (EFH). 660.75... Groundfish Fisheries § 660.75 Essential Fish Habitat (EFH). Essential fish habitat (EFH) is defined as those waters and substrate necessary to fish for spawning, breeding, feeding or growth to maturity (16 U.S.C...

50 CFR 660.395 - Essential Fish Habitat (EFH)

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Essential Fish Habitat (EFH) 660.395... Groundfish Fisheries § 660.395 Essential Fish Habitat (EFH) Essential fish habitat (EFH) is defined as those waters and substrate necessary to fish for spawning, breeding, feeding or growth to maturity (16 U.S.C...

Widespread microplastic ingestion by fish assemblages in tropical estuaries subjected to anthropogenic pressures.

PubMed

Vendel, A L; Bessa, F; Alves, V E N; Amorim, A L A; Patrício, J; Palma, A R T

2017-04-15

Our aim was to quantify microplastic ingestion by fish assemblages in two tropical Brazilian estuaries and to evaluate whether biological and ecological factors influence the ingestion of microplastics by fish species. Of 2233 fish from both estuaries (from 69 species) examined in this study, 9% of the individuals (24 species) had microplastics in their gut contents. Microplastic ingestion occurred irrespective of fish size and functional group. The diet of fish species was analyzed based on prey items identified in the fish's full stomach contents and five feeding guilds were defined. Microplastics were common throughout all feeding guilds. Low (average ingestion values 1.06±0.30 items/total fish) but widespread occurrence among estuaries also indicates proliferation of microplastic pollution. Our findings highlight the need to focus on assemblage level studies to understand the real magnitude of the problem and emphasize the urgency of mitigation measures directed at microplastic pollution in estuarine ecosystems. Copyright © 2017 Elsevier Ltd. All rights reserved.

FURTHER OBSERVATIONS AND EXPERIMENTS ON GOITRE (SO CALLED THYROID CARCINOMA) IN BROOK TROUT (SALVELINUS FONTINALIS)

PubMed Central

Marine, David

1914-01-01

1. Goitre in fish is a non-infectious, non-contagious, symptomatic manifestation of a fault of nutrition, the exact biochemical nature of which has not been determined. 2. Feeding the highly artificial and incomplete diet of liver is the major etiological factor in bringing about this fault of nutrition which is at once corrected by feeding whole sea fish. 3. Water plays no essential part in the etiology, transmission, or distribution of the disease in the fish of this hatchery. PMID:19867750

Gene expression analysis among rainbow trout selected for increased biosynthesis and muscle deposition of omega-3 fatty acids when fed plant protein and plant oil formulated feeds

USDA-ARS?s Scientific Manuscript database

Rainbow trout (Oncorhynchus mykiss) and other salmonids are piscivorous fish. In aquaculture, fish-based feed ingredients are rapidly becoming unsustainable due to increased demand and diminishing supply. Total replacement of fishmeal with plant proteins has been shown to cause severe intestinal ent...

75 FR 5887 - Listing of Color Additives Exempt From Certification; Paracoccus Pigment; Confirmation of...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-05

... pigment as a color additive in the feed of salmonid fish to enhance the color of their flesh. DATES: The... for the safe use of paracoccus pigment as a color additive in the feed of salmonid fish to enhance the... of Food and Drugs, and redelegated to the Director, Office of Food Additive Safety, notice is given...

Interactive effect of high environmental ammonia and nutritional status on ecophysiological performance of European sea bass (Dicentrarchus labrax) acclimated to reduced seawater salinities.

PubMed

Sinha, Amit Kumar; Rasoloniriana, Rindra; Dasan, Antony Franklin; Pipralia, Nitin; Blust, Ronny; De Boeck, Gudrun

2015-03-01

We investigated the interactive effect of ammonia toxicity, salinity challenge and nutritional status on the ecophysiological performance of European sea bass (Dicentrarchus labrax). Fish were progressively acclimated to normal seawater (32ppt), to brackish water (20ppt and 10ppt) and to hyposaline water (2.5ppt). Following acclimation to different salinities for two weeks, fish were exposed to high environmental ammonia (HEA, 20mg/L ∼1.18mM representing 50% of 96h LC50 value for ammonia) for 12h, 48h, 84h and 180h, and were either fed (2% body weight) or fasted (unfed for 7 days prior to HEA exposure). Biochemical responses such as ammonia (Jamm) and urea excretion rate, plasma ammonia, urea and lactate, plasma ions (Na(+), Cl(-) and K(+)) and osmolality, muscle water content (MWC) and liver and muscle energy budget (glycogen, lipid and protein), as well as branchial Na(+)/K(+)-ATPase (NKA) and H(+)-ATPase activity, and branchial mRNA expression of NKA and Na(+)/K(+)/2Cl(-) co-transporter (NKCC1) were investigated in order to understand metabolic and ion- osmoregulatory consequences of the experimental conditions. During HEA, Jamm was inhibited in fasted fish at 10ppt, while fed fish were still able to excrete efficiently. At 2.5ppt, both feeding groups subjected to HEA experienced severe reductions and eventually a reversion in Jamm. Overall, the build-up of plasma ammonia in HEA exposed fed fish was much lower than fasted ones. Unlike fasted fish, fed fish acclimated to lower salinities (10ppt-2.5ppt) could maintain plasma osmolality, [Na(+)], [Cl(-)] and MWC during HEA exposure. Thus fed fish were able to sustain ion-osmotic homeostasis which was associated with a more pronounced up-regulation in NKA expression and activity. At 2.5ppt both feeding groups activated H(+)-ATPase. The expression of NKCC1 was down-regulated at lower salinities in both fed and fasted fish, but was upregulated within each salinity after a few days of HEA exposure. Though an increment in plasma lactate content and a decline in energy stores were noted for both feeding regimes, the effect was more severe in feed deprived fish. Overall, several different physiological processes were disturbed in fasted sea bass during HEA exposure while feeding alleviated adverse effects of high ammonia and salinity challenge. This suggests that low food availability can render fish more vulnerable to external ammonia, especially at reduced seawater salinities. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of dietary fish meal replacement by red algae, Gracilaria arcuata, on growth performance and body composition of Nile tilapia Oreochromis niloticus.

PubMed

Younis, El-Sayed M; Al-Quffail, Abdullah S; Al-Asgah, Nasser A; Abdel-Warith, Abdel-Wahab A; Al-Hafedh, Yousef S

2018-02-01

A 12-week long feeding experiment was initiated to evaluate the effect of dietary supplementation of red algae, Gracilaria arcuata , on the growth performance, feed utilization and body composition of Nile tilapia Oreochromis niloticus (Linnaeus, 1758). The fish were fed with an algae-free control diet (C) and three experimental diets which replaced conventional fish meal with varying levels of dried G. arcuata (20%, 40% and 60%, represented as G20, G40 and G60, respectively). The growth parameters of final weight (FW), weight gain (WG), percentage of weight gain (WG%), daily growth rate (DGR) and specific growth rate (SGR) were significantly reduced (P < 0.05) at all levels of algae incorporation compared to the control diet. Moreover, the negative impact of Gracilaria meal on the growth performance of Nile tilapia increased as the proportion of algae in the diet increased, with fish on diet G20 exhibiting a significantly higher growth performance than the fish on either of the G40 and G60 diets. On the other hand, the feed utilization parameters feed conversion ratio (FCR) and protein efficiency ratio (PER) did not show significant differences between the fish in the control group and those on diet G20, although poorer FCR and PER outcomes were achieved in the case of fish on diet G60. The content of moisture, protein and ash in muscle and carcass increased as the proportion of Gracilaria meal in the diets increased, but the reverse was true for lipid level. These results indicate that incorporation of less than 20% red algae, Gracilaria arcuata , could be feasible in the diet of Nile tilapia and further studies are recommended to optimize the level of algae to improve growth performance.

Suction feeding across fish life stages: flow dynamics from larvae to adults and implications for prey capture.

PubMed

Yaniv, Sarit; Elad, David; Holzman, Roi

2014-10-15

Suction feeding is thought to be the primary mode of prey capture in most larval fishes. Similar to adult suction feeders, larvae swim towards their prey while rapidly expanding their mouth cavity to generate an inward flow of water that draws the prey into the mouth. Although larvae are known to experience flows with lower Reynolds numbers than adults, it is unclear how the suction-induced flow field changes throughout ontogeny, and how such changes relate to prey capture performance. To address these questions, we determined mouth dimensions and opening speeds in Sparus aurata from first-feeding larvae to adults. We proceeded to develop a computational model of mouth expansion in order to analyze the scaling of suction flows under the observed parameters. Larval fish produced suction flows that were around two orders of magnitude slower than those of adults. Compared with adult fish, in which flow speed decays steeply with distance in front of the mouth, flow speed decayed more gradually in larval fish. This difference indicates that viscous forces in low Reynolds number flows modify the spatial distribution flow speed in front of the mouth. Consequently, simulated predator-prey encounters showed that larval fish could capture inert prey from a greater distance compared with adults. However, if prey attempted to escape then larval fish performed poorly: simulations inferred capture success in only weakly escaping prey immediately in front of the mouth. These ontogenetic changes in Reynolds number, suction-induced flow field and feeding performance could explain a widespread ontogenetic diet shift from passive prey at early life stages to evasive prey as larvae mature. © 2014. Published by The Company of Biologists Ltd.

Fish mucus versus parasitic gnathiid isopods as sources of energy and sunscreens for a cleaner fish

NASA Astrophysics Data System (ADS)

Eckes, Maxi; Dove, Sophie; Siebeck, Ulrike E.; Grutter, Alexandra S.

2015-09-01

The cleaning behaviour of the bluestreak cleaner wrasse Labroides dimidiatus is extensively used as a model system for understanding cooperation. It feeds mainly on blood-sucking gnathiid isopods and also on the epidermal mucus of client fish; the nutritional quality of these foods, however, is unknown. The epidermal mucus of reef fish contains ultraviolet (UV)-absorbing compounds (mycosporine-like amino acids, MAAs), which are only obtained via the diet; nevertheless, while La. dimidiatus has high amounts of MAAs in its mucus, their source is unknown. Therefore, the energetic value (calories and protein estimated using carbon and nitrogen) and MAA level in gnathiids and mucus from several clients [parrotfishes, wrasses (Labridae), and a snapper (Lutjanidae)] were determined. The energetic value of mucus and gnathiids varied among fishes. Overall, carbon, nitrogen, calories, and protein per dry weight were higher in the mucus of most client species compared to gnathiids. Thus, depending on the client species, mucus may be energetically more advantageous for cleaner wrasse to feed on than gnathiids. UV absorbance, a confirmed proxy for MAA levels, indicated high MAA levels in mucus, whereas gnathiids had no detectable MAAs. This suggests that La. dimidiatus obtain MAAs from mucus but not from gnathiids. Hence, in addition to energy, the mucus of some clients also provides La. dimidiatus with the added bonus of UV-absorbing compounds. This may explain why cleaner fish prefer to feed on mucus over gnathiid isopods. The likely costs and benefits to clients of the removal of UV protecting mucus and parasitic gnathiids, respectively, and the variation in benefits gained by cleaner fish from feeding on these foods may explain some variation in cooperation levels in cleaning interactions.

Early migration and estuary stopover of introduced chinook salmon population in the Lapataia River Basin, southern Tierra del Fuego Island

NASA Astrophysics Data System (ADS)

Chalde, T.; Fernández, D. A.

2017-12-01

Established populations of chinook salmon (Oncorhynchus tshawytscha) have recently been reported in South America, at both Atlantic and Pacific basins. Several studies have evaluated different aspects of their life histories; however, little is known about the use of the estuaries by the juveniles of these populations. We examined spawning time, seaward migration timing, growth rate, scale patterns, diet, and geometric morphometric, contrasting the early life history during freshwater and estuary residence of a chinook population established in Lapataia Basin. Fall run spawning took place in March-April and the parr emerged in September. Two distinct seaward migration patterns were identified from sein net fishing records: one population segment migrating earlier to the estuary in October and a second group migrating later in February. The growth rate of fish captured at the estuary was significantly higher than the fish captured in freshwater. In addition, higher scale intercirculi distances were observed in estuary fish showing differences in growth rate. The feeding habitat in fish captured in both environments changed through time from bottom feeding to surface feeding and from significant diet overlap to no overlap. The morphology of the fish captured at the estuary was associated with the elongation of the caudal peduncle and a decrease in the condition factor index, both changes related to smolt transformation. The earlier migration and the higher growth rate of juveniles in the estuary together with fish of 1 + yo captured in this environment reveal that the estuary of Lapataia Basin is not only a stopover for the chinook salmon, but also a key habitat to reside and feed previous to the final seaward migration.

25 CFR 242.3 - Authority to operate.

Code of Federal Regulations, 2010 CFR

2010-04-01

... OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE COMMERCIAL FISHING ON RED LAKE INDIAN RESERVATION § 242.3 Authority to operate. The association may conduct commercial fishing operations on the reservation under authority of its articles of incorporation and by-laws only in accordance with the...

Replication and persistence of VHSV IVb in freshwater turtles.

PubMed

Goodwin, Andrew E; Merry, Gwenn E

2011-05-09

With the emergence of viral hemorrhagic septicemia virus (VHSV) strain IVb in the Great Lakes of North America, hatchery managers have become concerned that this important pathogen could be transmitted by animals other than fish. Turtles are likely candidates because they are poikilotherms that feed on dead fish, but there are very few reports of rhabdovirus infections in reptiles and no reports of the fish rhabdoviruses in animals other than teleosts. We injected common snapping turtles Chelydra serpentine and red-eared sliders Trachemys scripta elegans intraperitoneally with 10(4) median tissue culture infectious dose (TCID50) of VHSV-IVb and 21 d later were able to detect the virus by quantitative real-time reverse transcriptase PCR (qrt-RTPCR) in pools of kidney, liver, and spleen. In a second experiment, snapping turtles, red-eared sliders, yellow-bellied sliders T. scripta scripta, and northern map turtles Grapetemys geographica at 14 degrees C were allowed to feed on tissues from bluegill dying of VHSV IVb disease. Turtle kidney, spleen, and brain pools were not positive by qrt-RTPCR on Day 3 post feeding, but were positive on Days 10 and 20. Map turtles on Day 20 post-feeding were positive by both qrt-RTPCR and by cell culture. Our work shows that turtles that consume infected fish are a possible vector for VHSV IVb, and that the fish rhabdoviruses may have a broader host range than previously suspected.

Effects of protein hydrolysates supplementation in low fish meal diets on growth performance, innate immunity and disease resistance of red sea bream Pagrus major.

PubMed

Khosravi, Sanaz; Rahimnejad, Samad; Herault, Mikaël; Fournier, Vincent; Lee, Cho-Rong; Dio Bui, Hien Thi; Jeong, Jun-Bum; Lee, Kyeong-Jun

2015-08-01

This study was conducted to evaluate the supplemental effects of three different types of protein hydrolysates in a low fish meal (FM) diet on growth performance, feed utilization, intestinal morphology, innate immunity and disease resistance of juvenile red sea bream. A FM-based diet was used as a high fish meal diet (HFM) and a low fish meal (LFM) diet was prepared by replacing 50% of FM by soy protein concentrate. Three other diets were prepared by supplementing shrimp, tilapia or krill hydrolysate to the LFM diet (designated as SH, TH and KH, respectively). Triplicate groups of fish (4.9 ± 0.1 g) were fed one of the test diets to apparent satiation twice daily for 13 weeks and then challenged by Edwardsiella tarda. At the end of the feeding trial, significantly (P < 0.05) higher growth performance was obtained in fish fed HFM and hydrolysate treated groups compared to those fed the LFM diet. Significant improvements in feed conversion and protein efficiency ratios were obtained in fish fed the hydrolysates compared to those fed the LFM diet. Significant enhancement in digestibility of protein was found in fish fed SH and KH diets and dry matter digestibility was increased in the group fed SH diet in comparison to LFM group. Fish fed the LFM diet showed significantly higher glucose level than all the other treatments. Whole-body and dorsal muscle compositions were not significantly influenced by dietary treatments. Histological analysis revealed significant reductions in goblet cell numbers and enterocyte length in the proximal intestine of fish fed the LFM diet. Superoxide dismutase activity and total immunoglobulin level were significantly increased in fish fed the diets containing protein hydrolysates compared to the LFM group. Also, significantly higher lysozyme and antiprotease activities were found in fish fed the hydrolysates and HFM diets compared to those offered LFM diet. Fish fed the LFM diet exhibited the lowest disease resistance against E. tarda and dietary inclusion of the hydrolysates resulted in significant enhancement of survival rate. The results of the current study indicated that the inclusion of the tested protein hydrolysates, particularly SH, in a LFM diet can improve growth performance, feed utilization, digestibility, innate immunity and disease resistance of juvenile red sea bream. Copyright © 2015 Elsevier Ltd. All rights reserved.

Fish oil replacement in current aquaculture feed: is cholesterol a hidden treasure for fish nutrition?

PubMed

Norambuena, Fernando; Lewis, Michael; Hamid, Noor Khalidah Abdul; Hermon, Karen; Donald, John A; Turchini, Giovanni M

2013-01-01

Teleost fish, as with all vertebrates, are capable of synthesizing cholesterol and as such have no dietary requirement for it. Thus, limited research has addressed the potential effects of dietary cholesterol in fish, even if fish meal and fish oil are increasingly replaced by vegetable alternatives in modern aquafeeds, resulting in progressively reduced dietary cholesterol content. The objective of this study was to determine if dietary cholesterol fortification in a vegetable oil-based diet can manifest any effects on growth and feed utilization performance in the salmonid fish, the rainbow trout. In addition, given a series of studies in mammals have shown that dietary cholesterol can directly affect the fatty acid metabolism, the apparent in vivo fatty acid metabolism of fish fed the experimental diets was assessed. Triplicate groups of juvenile fish were fed one of two identical vegetable oil-based diets, with additional cholesterol fortification (high cholesterol; H-Chol) or without (low cholesterol; L-Chol), for 12 weeks. No effects were observed on growth and feed efficiency, however, in fish fed H-Col no biosynthesis of cholesterol, and a remarkably decreased apparent in vivo fatty acid β-oxidation were recorded, whilst in L-Chol fed fish, cholesterol was abundantly biosynthesised and an increased apparent in vivo fatty acid β-oxidation was observed. Only minor effects were observed on the activity of stearyl-CoA desaturase, but a significant increase was observed for both the transcription rate in liver and the apparent in vivo activity of the fatty acid Δ-6 desaturase and elongase, with increasing dietary cholesterol. This study showed that the possible effects of reduced dietary cholesterol in current aquafeeds can be significant and warrant future investigations.

Management of marine cage aquaculture. Environmental carrying capacity method based on dry feed conversion rate.

PubMed

Cai, Huiwen; Sun, Yinglan

2007-11-01

Marine cage aquaculture produces a large amount of waste that is released directly into the environment. To effectively manage the mariculture environment, it is important to determine the carrying capacity of an aquaculture area. In many Asian countries trash fish is dominantly used in marine cage aquaculture, which contains more water than pellet feed. The traditional nutrient loading analysis is for pellet feed not for trash fish feed. So, a more critical analysis is necessary in trash fish feed culturing areas. Corresponding to FCR (feed conversion rate), dry feed conversion rate (DFCR) was used to analyze the nutrient loadings from marine cage aquaculture where trash fish is used. Based on the hydrodynamic model and the mass transport model in Xiangshan Harbor, the relationship between the water quality and the waste discharged from cage aquaculture has been determined. The environmental carrying capacity of the aquaculture sea area was calculated by applying the models noted above. Nitrogen and phosphorus are the water quality parameters considered in this study. The simulated results show that the maximum nitrogen and phosphorus concentrations were 0.216 mg/L and 0.039 mg/L, respectively. In most of the sea area, the nutrient concentrations were higher than the water quality standard. The calculated environmental carrying capacity of nitrogen and phosphorus in Xiangshan Harbor were 1,107.37 t/yr and 134.35 t/yr, respectively. The waste generated from cage culturing in 2000 has already exceeded the environmental carrying capacity. Unconsumed feed has been identified as the most important origin of all pollutants in cage culturing systems. It suggests the importance of increasing the feed utilization and improving the feed composition on the basis of nutrient requirement. For the sustainable development of the aquaculture industry, it is an effective management measure to keep the stocking density and pollution loadings below the environmental carrying capacity. The DFCR-based nutrient loadings analysis indicates, in trash fish feed culturing areas, that it is more critical and has been proved to be a valuable loading calculation method. The modeling approach for Xiangshan Harbor presented in this paper is a cost-effective method for assessing the environmental impact and determining the capacity. Carrying capacity information can give scientific suggestions for the sustainable management of aquaculture environments. It has been proved that numerical models were convenient tools to predict the environmental carrying capacity. The development of models coupled with dynamic and aquaculture ecology is a requirement of further research. Such models can also be useful in monitoring the ecological impacts caused by mariculture activities.

Stocking of Offsite Waters for Hungry Horse Dam Mitigation Creston National Fish Hatchery, FY 2006 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hooley, Sharon

2009-03-20

A total of 350,000, M012 strain, westslope cutthroat trout (WCT) eggs were received from Montana Fish Wildlife & Parks (MFWP), Washoe Park State Fish Hatchery in June of 2005 to accomplish this fishery management objective. These eggs were incubated, hatched and reared entirely inside the hatchery nursery building using a protected well water supply. Fish grew according to schedule and survival was excellent. The hatchery achieved a 0.78 feed fed to pounds gained conversion ratio for this group of WCT. Not all of the progenies from this fish lot were used for Hungry Horse Dam Fishery Mitigation Implementation. Some weremore » used for other regional fishery management projects. Westslope cutthroat trout were reared using approved fish culture techniques as recommended in the USFWS Fish Hatchery Management Handbook and also utilizing a regimen adapted for hatchery specific site conditions. The fish health for these WCT was very good. Survival from first feeding fry stage to stocking was 79%. The hatchery had an annual fish health inspection performed by the USFWS Bozeman Fish Health Center in mid March of 2006. This inspection found all fish lots at Creston to be disease free. The Montana State Fish Health Board has placed the hatchery under a limited quarantine since May of 2005 due to an epizootic of Furunculosis. This classification has allowed the Creston NFH to stock disease free fish in locations approved by regional fish managers. The hatchery has been working with the State Fish Pathologist to remove the limited quarantine classification from the facility. Although fish health for all station fish lots remains disease free, MFWP has asserted it will not remove the limited quarantine until the new influent water treatment system, including the ultraviolet disinfection unit, is running full time, year round. The USFWS is working to secure the additional funding necessary to operate the treatment building year round. Distribution of the WCT took place from March through June. The stocking locations on the Flathead Reservation and State managed waters were identified by Confederated Salish and Kootenai Tribe (CSKT) and MFWP fishery biologists. Post release survival and angler success is monitored routinely by CSKT and MFWP fishery technicians. Stocking numbers and locations vary annually based on the results of biological monitoring, creel evaluations and adaptive management decisions. A total of 99,126 WCT were stocked during nine distribution trips in management approved waters (see Table 1). The average size of WCT at stocking was 3.91-inches. A total of 101,600, Arlee strain, rainbow trout (RBT) eggs were received from the Ennis National Fish Hatchery, Ennis, Montana, in December of 2005 and 35,000 Kamloops strain eggs were received from Murray Springs SFH, Eureka, Montana, in March of 2006 to accomplish this fishery management objective. The RBT were reared using approved fish culture techniques as recommended in the USFWS Fish Hatchery Management Handbook. There was no fish health related problems associated with this lot of fish. Survival from swim up fry stage to stocking was 93% for the Arlee's and 79% for the Kamloops. The hatchery achieved a 0.68 feed fed to pounds gained conversion ratio for the Arlee and 0.97 for the Kamloops RBT. The excellent feed conversion ratio can be attributed to refined feeding techniques and the use of an extruded high performance fry feed made with premium fish meal and marine fish oil. The Arlee strain of rainbow trout is requested for this fishery mitigation objective because the chosen stocking locations are terminal basin reservoirs or lakes, habitat conditions prevent natural spawning runs and returns to the creel are more favorable then for native westslope cutthroat trout. MFWP also requested a fall plant of Kamloops strain RBT and they will be evaluated for performance and future fall stockings in Echo Lake. Post release survival and angler success is monitored routinely by the Confederated Salish and Kootenai Tribe (CSKT) and Montana Fish Wildlife & Parks (MFWP) fishery technicians. Stocking numbers and locations vary annually based on the results of biological monitoring, creel evaluations and habitat conditions. The RBT were stocked in six distribution trips from June through September. The number of fish stocked and the receiving waters are identified below (see Table 2).« less

Indicators: Shallow Water Habitat/In-stream Fish Habitat

EPA Pesticide Factsheets

Shallow water habitat, also referred to as in-stream fish habitat, refers to areas that fish and other aquatic organisms need for concealment, breeding and feeding. This includes large woody snags, boulders, rock ledges, and undercut banks.

Microplastics in gut contents of coastal freshwater fish from Río de la Plata estuary.

PubMed

Pazos, Rocío S; Maiztegui, Tomás; Colautti, Darío C; Paracampo, Ariel H; Gómez, Nora

2017-09-15

The presence of microplastics (MPs) in gut contents of coastal freshwater fish of the Rio de la Plata estuary was studied. Samples were taken in six sites where 87 fish belonging to 11 species and four feeding habits were captured. Presence of MPs was verified in the 100% of fish. The fibres represented the 96% of MPs found. The number of MPs in gut contents was significantly higher close to sewage discharge. There was not found relationship between number of MPs and fish length, weight or feeding habit. The spatial differences in mean number of MPs in fish observed in this study, suggest that environmental availability of MPs could be of great importance to explain the differences found among sampling sites analysed. This work represents the first study about the interaction between MPs and aquatic organisms in this important estuarine ecosystem of South America. Copyright © 2017 Elsevier Ltd. All rights reserved.

The effect of shelter on welfare of juvenile Atlantic salmon Salmo salar reared under a feed restriction regimen.

PubMed

Persson, L; Alanärä, A

2014-09-01

This study investigated whether shelter (presence or absence) affected the frequency of fin damage in Atlantic salmon Salmo salar exposed to feed restrictions (0·73 or 0·33% of body mass day(-1) ). The presence of shelter had a positive effect on the pectoral fins at both feed ration levels and on the dorsal fin at the higher ration level but it had a negative effect on survival. The reduced feed rations resulted in fish of the same size and nutritional status as wild fish. The provision of shelter has potential to mitigate the negative effects of feed restrictions on fin quality, but the optimal shelter design requires some additional investigation. © 2014 The Fisheries Society of the British Isles.

75 FR 7445 - Western Pacific Fishery Management Council; Public Meetings

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-19

... measures for non-commercial fishing in the Rose Atoll Marine National Monument and Pacific Remote Islands... fishing in the Rose Atoll Marine National Monument as prescribed in Presidential Proclamation 8337... limited to issues regarding non-commercial fishing in the Rose Atoll Marine National Monument and the...

How to find a web interface for successful education (WISEbyte).

PubMed

Jacobs, Joshua L

2012-01-01

'Give a man a fish and you feed him for a day. Teach him how to fish, and you feed him for a lifetime…'. Although the exact origin of this proverb is unknown, its meaning is clear and wisdom self-evident. In the field of health professions education, there are many websites that can be used as teaching aids, some of which have undergone peer review. Some organizations have created repositories of online teaching materials hosted by various organizations. You can certainly find a lot of 'fish' there to feed your appetite for high-quality teaching materials. For examples of repositories that contain online teaching materials, see Table 1. However, these repositories and other lists of websites cannot be comprehensive, so it is important to know the basic review skills to evaluate websites that may be useful for your teaching that you come across in your journeys around the web. This article intends to teach you 'how to fish' for useful web-based teaching resources to help you succeed as a clinical teacher.

Sediment transport by fishes in Harrington Sound, Bermuda

NASA Astrophysics Data System (ADS)

Alheit, Jürgen

1983-11-01

Harrington Sound, Bermuda, is a shallow subtropical lagoon with carbonate sediments. The most important fishes in this lagoon, in terms of biomass, are grunts (Haemulon aurolineatum, H. flavolineatum, H. sciurus) and a sea-bream (Diplodus bermudensis). These undertake diel feeding migrations from the shallow rocky zone towards the deeper sand and mud zones. When feeding on zoobenthos they cannot avoid swallowing carbonate sediment particles. These sediment particles pass through the alimentary canal of the fishes and are deposited again, after digestion of the food, as faeces in the shallow zones. Thus, the fishes transport the sediment in an unusual direction, from the deep to the shallow zones, in effect against the force of gravity. By recording the fish stock densities, digestion rates, and calcium carbonate content of fish stomach and guts, it was possible to estimate the amount of sediment transported by the fishes. In Harrington Sound, this amounts annually to 4530 kg calcium carbonate, 40% of which is deposited in the very shallow areas. The pH-values measured in fish stomachs seem to be acidic enough for the dissolution of carbonate sediment particles when transported by fishes.

Is the feeding type related with the content of microplastics in intertidal fish gut?

PubMed

Mizraji, Ricardo; Ahrendt, Camila; Perez-Venegas, Diego; Vargas, Juan; Pulgar, Jose; Aldana, Marcela; Patricio Ojeda, F; Duarte, Cristian; Galbán-Malagón, Cristobal

2017-03-15

Microplastics pollution is a growing global concern that affects all aquatic ecosystems. Microplastics in the environment can be in the form of fibers and/or particles, being the former the most abundant in the marine environment, representing up to 95% of total plastics. The aim of this work was to compare the content of microplastics among intertidal fish with different feeding type. Our results show that omnivorous fish presented a higher amount of microplastic fibers than registered in herbivores and carnivores. Moreover, lower condition factors (K) were found in omnivorous specimens with higher microplastic content. We hypothesized that the type of feeding resulted in different microplastic ingestion, with species with wider range of food sources as omnivores with higher rates. Futures studies carried out to evaluate the biological impacts of microplastics on marine organisms, and microplastics cycling on the marine environment should consider the type of feeding of the studied species. Copyright © 2017 Elsevier Ltd. All rights reserved.

Quantitative estimate of commercial fish enhancement by seagrass habitat in southern Australia

NASA Astrophysics Data System (ADS)

Blandon, Abigayil; zu Ermgassen, Philine S. E.

2014-03-01

Seagrass provides many ecosystem services that are of considerable value to humans, including the provision of nursery habitat for commercial fish stock. Yet few studies have sought to quantify these benefits. As seagrass habitat continues to suffer a high rate of loss globally and with the growing emphasis on compensatory restoration, valuation of the ecosystem services associated with seagrass habitat is increasingly important. We undertook a meta-analysis of juvenile fish abundance at seagrass and control sites to derive a quantitative estimate of the enhancement of juvenile fish by seagrass habitats in southern Australia. Thirteen fish of commercial importance were identified as being recruitment enhanced in seagrass habitat, twelve of which were associated with sufficient life history data to allow for estimation of total biomass enhancement. We applied von Bertalanffy growth models and species-specific mortality rates to the determined values of juvenile enhancement to estimate the contribution of seagrass to commercial fish biomass. The identified species were enhanced in seagrass by 0.98 kg m-2 y-1, equivalent to ˜$A230,000 ha-1 y-1. These values represent the stock enhancement where all fish species are present, as opposed to realized catches. Having accounted for the time lag between fish recruiting to a seagrass site and entering the fishery and for a 3% annual discount rate, we find that seagrass restoration efforts costing $A10,000 ha-1 have a potential payback time of less than five years, and that restoration costing $A629,000 ha-1 can be justified on the basis of enhanced commercial fish recruitment where these twelve fish species are present.

Modelling the nitrogen loadings from large yellow croaker (Larimichthys crocea) cage aquaculture.

PubMed

Cai, Huiwen; Ross, Lindsay G; Telfer, Trevor C; Wu, Changwen; Zhu, Aiyi; Zhao, Sheng; Xu, Meiying

2016-04-01

Large yellow croaker (LYC) cage farming is a rapidly developing industry in the coastal areas of the East China Sea. However, little is known about the environmental nutrient loadings resulting from the current aquaculture practices for this species. In this study, a nitrogenous waste model was developed for LYC based on thermal growth and bioenergetic theories. The growth model produced a good fit with the measured data of the growth trajectory of the fish. The total, dissolved and particulate nitrogen outputs were estimated to be 133, 51 and 82 kg N tonne(-1) of fish production, respectively, with daily dissolved and particulate nitrogen outputs varying from 69 to 104 and 106 to 181 mg N fish(-1), respectively, during the 2012 operational cycle. Greater than 80 % of the nitrogen input from feed was predicted to be lost to the environment, resulting in low nitrogen retention (<20 %) in the fish tissues. Ammonia contributed the greatest proportion (>85 %) of the dissolved nitrogen generated from cage farming. This nitrogen loading assessment model is the first to address nitrogenous output from LYC farming and could be a valuable tool to examine the effects of management and feeding practices on waste from cage farming. The application of this model could help improve the scientific understanding of offshore fish farming systems. Furthermore, the model predicts that a 63 % reduction in nitrogenous waste production could be achieved by switching from the use of trash fish for feed to the use of pelleted feed.

Feed conversion efficiency in aquaculture: do we measure it correctly?

NASA Astrophysics Data System (ADS)

Fry, Jillian P.; Mailloux, Nicholas A.; Love, David C.; Milli, Michael C.; Cao, Ling

2018-02-01

Globally, demand for food animal products is rising. At the same time, we face mounting, related pressures including limited natural resources, negative environmental externalities, climate disruption, and population growth. Governments and other stakeholders are seeking strategies to boost food production efficiency and food system resiliency, and aquaculture (farmed seafood) is commonly viewed as having a major role in improving global food security based on longstanding measures of animal production efficiency. The most widely used measurement is called the ‘feed conversion ratio’ (FCR), which is the weight of feed administered over the lifetime of an animal divided by weight gained. By this measure, fed aquaculture and chickens are similarly efficient at converting feed into animal biomass, and both are more efficient compared to pigs and cattle. FCR does not account for differences in feed content, edible portion of an animal, or nutritional quality of the final product. Given these limitations, we searched the literature for alternative efficiency measures and identified ‘nutrient retention’, which can be used to compare protein and calories in feed (inputs) and edible portions of animals (outputs). Protein and calorie retention have not been calculated for most aquaculture species. Focusing on commercial production, we collected data on feed composition, feed conversion ratios, edible portions (i.e. yield), and nutritional content of edible flesh for nine aquatic and three terrestrial farmed animal species. We estimate that 19% of protein and 10% of calories in feed for aquatic species are ultimately made available in the human food supply, with significant variation between species. Comparing all terrestrial and aquatic animals in the study, chickens are most efficient using these measures, followed by Atlantic salmon. Despite lower FCRs in aquaculture, protein and calorie retention for aquaculture production is comparable to livestock production. This is, in part, due to farmed fish and shrimp requiring higher levels of protein and calories in feed compared to chickens, pigs, and cattle. Strategies to address global food security should consider these alternative efficiency measures.