Influences of thermal environment on fish growth

Indexación: Scopus.Thermoregulation in ectothermic animals is influenced by the ability to effectively respond to thermal variations. While it is known that ectotherms are affected by thermal changes, it remains unknown whether physiological and/or metabolic traits are impacted by modifications to the thermal environment. Our research provides key evidence that fish ectotherms are highly influenced by thermal variability during development, which leads to important modifications at several metabolic levels (e.g., growth trajectories, microstructural alterations, muscle injuries, and molecular mechanisms). In Atlantic salmon (Salmo salar), a wide thermal range (ΔT 6.4°C) during development (posthatch larvae to juveniles) was associated with increases in key thermal performance measures for survival and growth trajectory. Other metabolic traits were also significantly influenced, such as size, muscle cellularity, and molecular growth regulators possibly affected by adaptive processes. In contrast, a restricted thermal range (ΔT 1.4°C) was detrimental to growth, survival, and cellular microstructure as muscle growth could not keep pace with increased metabolic demands. These findings provide a possible basic explanation for the effects of thermal environment during growth. In conclusion, our results highlight the key role of thermal range amplitude on survival and on interactions with major metabolism-regulating processes that have positive adaptive effects for organisms.http://onlinelibrary.wiley.com/doi/10.1002/ece3.3239/ful

Bayesian Bioeconomics of Marine Reserves

We use Bayesian econometric methods to estimate dynamic bioeconomic models of marine reserve formation using simulated data and real data from the Gulf of Mexico reef fish fishery. We test the effects of reserves on fish growth and catchability.Resource /Energy Economics and Policy,

Fish growth parameters and their monitoring

Recent studies have predicted that fish consumption in developing and developed countries will increase by 57 percent and 4 percent, respectively. Rapid population growth, increasing affluence and urbanization in developing countries are leading to major changes in supply and demand for animal protein, from both livestock and fish. The need for suitable sites has resulted in the cage aquaculture subsector accessing and expanding into new untapped open-water culture areas such as lakes, reservoirs, rivers and coastal brackish and marine offshore water

SOUND OF PADDLE WHEEL ON SEA BASS GROWTH

The objective of this research is sound effect for brackish water for Sea bass (Cynoscion nobilis). Breeding farm 25x100m, 2m of depth, and 6 paddle wheels which generate the sound are available for research. Sound profile has been measured to investigate the amplitude at various measurement points at various depths by using Cetacean hydrophone C304. The output of hydrophone has been analyzed by using SpectraPlus software. For the second measurement, two cages which size 3x3m have been used for life fish habitat. Then, fish put in the edge cage (20), center cage (20), and out of cage (12500). Sound profile has been measured for position-based (edge/center cage), time-based (morning/noon/evening), and point-based. Time series, spectrum frequency, and phase have been analysis. Fish growth progress has been monthly measured at every cage. Fish in the cage is growth as linearly, while fish growth for out of cage is exponentially. Size and weight of fish in the both cages is less than out of cage. This research concludes that sound have no significantly effect for fish growth. Limited mobility to look for food and stress are more influences to fish growth than sound effect

Integration of technologies for understanding the functional relationship between reef habitat and fish growth and production

Functional linkage between reef habitat quality and fish growth and production has remained elusive. Most current research is focused on correlative relationships between a general habitat type and presence/absence of a species, an index of species abundance, or species diversity. Such descriptive information largely ignores how reef attributes regulate reef fish abundance (density-dependent habitat selection), trophic interactions, and physiological performance (growth and condition). To determine the functional relationship between habitat quality, fish abundance, trophic interactions, and physiological performance, we are using an experimental reef system in the northeastern Gulf of Mexico where we apply advanced sensor and biochemical technologies. Our study site controls for reef attributes (size, cavity space, and reef mosaics) and focuses on the processes that regulate gag grouper (Mycteroperca microlepis) abundance, behavior and performance (growth and condition), and the availability of their pelagic prey. We combine mobile and fixed-active (fisheries) acoustics, passive acoustics, video cameras, and advanced biochemical techniques. Fisheries acoustics quantifies the abundance of pelagic prey fishes associated with the reefs and their behavior. Passive acoustics and video allow direct observation of gag and prey fish behavior and the acoustic environment, and provide a direct visual for the interpretation of fixed fisheries acoustics measurements. New application of biochemical techniques, such as Electron Transport System (ETS) assay, allow the in situ measurement of metabolic expenditure of gag and relates this back to reef attributes, gag behavior, and prey fish availability. Here, we provide an overview of our integrated technological approach for understanding and quantifying the functional relationship between reef habitat quality and one element of production – gag grouper growth on shallow coastal reefs

TRIVALENT CHROMIUM (CR+3) IN DIETARY CARBOHYDRATE AND ITS EFFECT ON THE GROWTH OF COMMONLY CULTIVATED FISH

Trivalent chromium (Cr+3) is an essential trace mineral for fish bio-physiological functions. Researches on Cr+3 in the form of organic compound indicated that the mineral affected the bio-activity of insulin, the blood glucose influx, and subsequently the blood glucose metabolic rate. By increasing the blood glucose metabolism, dietary carbohydrate will be more efficiently used as a main energy source, thereby, dietary protein could be efficiently retained as for somatic growth. Researches on various feeding habits of fish (e.g. gouramy-herbivorous fish, tilapia-omnivorous fish, and catfish-carnivorous fish) showed that dietary Cr+3 in certain amount increased diet utilization and the fish growth. Keywords: Blood glucose, chromium, feed, fish, growt

Fly fish growth pattern (Decapterus spp) in Likupang Water, Nort Sulawesi

This study was aimed to find out the size distribution of scad (Decapterus spp) caught by Likupang fishermen and to find out theirgrowth patterns. Fish samples were collected by traditional purse seine fishermen in Likupang waters. Total catches were 139 individuals consisting of 89 D. macarellus and 50 D. macrosoma.The former was dominated by size of 19.2-20.6 cm, while the latter was dominated by size of 13.1-14.1 cm. Length-weight relationship analysis showed that the growth patterns of D. macarellus and D. Macrosoma were isometric meaning that the increase in length is consistent with weight gain.Keywords: Likupang, Decapterus spp and growth patternsABSTRAKPenelitian ini bertujuan untuk mengetahui distribusi ukuran ikan layang (Decapterus spp) yang ditangkap oleh nelayan Likupang and untuk menduga pola pertumbuhannya. Sampel ikan diperoleh nelayan tradisional pukat cincin di perairan Likupang.Total hasil tangkapan adalah 139 ekor terdiri dari 89 ekor  D. macarellus dan 50 D. macrosoma. Hasil tangkapan D. macarellus didominasi oleh kelas ukuran 19,2-20,6 cm, sedangkan D. macrosomadidominasi oleh kelas ukuran 13,1-14,1 cm. Analisis hubungan panjang berat menunjukkan bahwa pola pertumbuhan ikan D. macarellusdan D. macrosoma bersifat isometrik yang artinya pertambahan panjang selaras dengan pertambahan berat.Kata kunci: Likupang, Decapterus spp dan Pola pertumbuha

Water Stability and Nutrient Leaching of Different Levels of Maltose Formulated Fish Pellets

The effects of different levels of maltose on feed pellet water stability and nutrient leaching were studied. Five treatments, including control with three replicates with setup (0.0, 20, 25, 30 and 35%). Pellet leaching rates were used to indicate pellet water stability. The results show that the presence of maltose in the diets significantly improved pellet water stability (p<0.05), but the leaching rates of the feed (35% maltose) observed higher than other feeds. Increased maltose resulted in the corresponding decrease in pellet stability. The protein leaching rate of control feed and feed (20% maltose) was significantly (p < 0.05) lower than the rates of other diets The lipid leaching rate of control feed was lower than the rates of other diets, while the feed (35% maltose) was more leaching rate. It improved feeds water stability is one important reason why maltose enhances fish growth

Seasonal changes in growth of coho salmon (Oncorhynchus kisutch) off Oregon and Washington and concurrent changes in the spacing of scale circuli

In this study we present new information on seasonal variation in absolute growth rate in length of coho salmon (Oncorhynchus kisutch) in the ocean off Oregon and Washington, and relate these changes in growth rate to concurrent changes in the spacing of scale circuli. Average spacing of scale circuli and average rate of circulus formation were significantly and positively correlated with average growth rate among groups of juvenile and maturing coho salmon and thus could provide estimates of growth between age groups and seasons. Regression analyses indicated that the spacing of circuli was proportional to the scale growth rate raised to the 0.4−0.6 power. Seasonal changes in the spacing of scale circuli reflected seasonal changes in apparent growth rates of fish. Spacing of circuli at the scale margin was greatest during the spring and early summer, decreased during the summer, and was lowest in winter or early spring. Changes over time in length of fish caught during research cruises indicated that the average growth rate of juvenile coho salmon between June and September was about 1.3 mm/d and then decreased during the fall and winter to about 0.6 mm/d. Average growth rate of maturing fish was about 2 mm/d between May and June, then decreased to about 1 mm/d between June and September. Average apparent growth rates of groups of maturing coded-wire−tagged coho salmon caught in the ocean hook-and-line fisheries also decreased between June and September. Our results indicate that seasonal change in the spacing of scale circuli is a useful indicator of seasonal change in growth rate of coho salmon in the ocean