Popular Fish Species Research Articles

The Determination of Lead, Arsenic, Mercury, Cadmium Contents in Some Edible Fish Species Retailed in Ibadan, Nigeria

Objective: The objective of this present study was to measure the contributions of some toxic heavy metals; namely lead, cadmium, arsenic and chromium in some edible fishes of marine origin (seafood) to the overall dietary intake of heavy metals in Ibadan, Nigeria. Materials and Methods: The samples under investigation were popular edible fish species namely; Scomber scombrus (mackerel), Haerengula jaguana (Sardine), Gadus morhua (Stockfish) and Exocoetidae volitans (flying fish) retailed in five open markets in Ibadan Metropolis, Nigeria. Sampling involved randomly procuring frozen forms of each of the experimental sample with an average length of 33.2cm in triplicate from each of the five markets on weekly basis for a month. A total of sixty samples per variety of fish used in this study was prepared for analysis by processes of homogenization and digestion of the whole fish (after their intestines have been removed); after which their individual lead, cadmium, arsenic and chromium contents were estimated by atomic absorption spectrophotometry. Results: The results revealed mean concentrations ranges in mg/kg as follows: lead (0.24 – 1.08), arsenic (0.02 – 0.19), mercury (0.16 – 0.64), and cadmium (0.13 – 0.36) in the fish samples analyzed. The mean concentrations and the estimated tolerable weekly intake (TWI) values respectively exceeded acceptable WHO/FAO permissible and tolerable weekly limits Conclusion: It can be concluded based on the findings of this present study that dietary fishes of marine origin may significantly contribute to an overall ingestion of heavy metals by the population of Ibadan. Further investigations on this present subject matter are hereby suggested.

Anatomical and Histological Characteristics of the Intestine of the Topmouth Culter (Culter alburnus)

With 3 figures and 1 table Topmouth culter (Culter alburnus), a freshwater carnivorous fish of the Cyprinidae, is one of the most popular fish species in aquatic market in China. The anatomy and histology features of fish intestine are very useful for understanding digestive physiology, diagnosing some intestinal diseases and formulating suitable feeds. Thus, here we first characterize topmouth culter intestine via light microscope, transmission electron microscope and scan electron microscope. The 'Z' shaped intestine can be divided into three parts (e.g. the anterior intestine, middle intestine and posterior intestine), with an intestinal coefficient of 0.68. The anterior intestine possessed the longest mucosa folds and thickest muscularis among the three intestinal parts, and microvilli were very well-developed whilst many mitochondria, endoplasmic reticulums and lysosomes were found in which. This indicated the anterior intestine was a main region for digestion and absorption of food in the topmouth culter. While the vacuoles observed in the posterior intestine may be closely related to the intracellular digestion. Neutral and acid mucus were strongly present throughout the intestine. This detailed descriptive paper will be very helpful for studies of topmouth culter related to its digestive physiology, intestinal disease control and feed nutrient.

Monoclonal Antibody‐Based Sandwich ELISA for Reliable Identification of Imported Pangasius Catfish

Pangasius catfish, primarily tra (Pangasius hypophthalmus) and basa (Pangasius bocourti), are farm-raised catfish imported from Asia and have become a common substitute for domestic catfish, grouper, and other high-valued fish in restaurant-served dishes in the United States. This article reports on the development of a monoclonal antibody-based sandwich enzyme-linked immunosorbent assay (ELISA) for the identification of cooked Pangasius fish, basa, and tra. The assay uses a pair of monoclonal antibodies (MAbs F7B8 and T7E10) specific to a heat-stable 36-kDa protein present in a saline extraction of the fish muscle; MAb F7B8, which cross-reacts to all fish species, is the capture antibody and the biotin-conjugated MAb T7E10, which is specific to Pangasius fish, is the detection antibody. This sandwich ELISA reliably identified fully cooked basa and tra from more than 70 common finfish, shellfish, land animal species, and other protein materials tested. It can also sensitively detect 0.5% of adulterated basa or 0.1% tra in a mixed crabmeat products with low intra-assay (%CV: 2.59 to 4.14) and inter-assay (%CV: 3.36 to 3.71) variabilities. The new assay provides a rapid and reliable means of distinguishing fish in the Pangasiidae family from other common food fish and nonfish species and will greatly assist efforts to discourage the illegal practice of substituting high-value popular fish species by the cheaper farm-raised imported Pangasius fish at the retail and restaurant levels.

Substitute and complement relations among various fish species in the Japanese market: implications for fishery resource management

A demand system analysis was conducted to examine the substitute relationships between tuna and skipjack tuna in the Japanese market. Data from the Annual Report on Family Income and Expenditure Survey from 1965 to 2006 were used for the analysis using the almost ideal demand system (AIDS). Results suggest that skipjack tuna can be a strong substitute for tuna, while other fish groups are not a clear substitute. Our analysis of substitute relationships among fish species in a market indicates that this is a factor that should be considered for better fisheries resource management. For instance, even under a situation where one fish species is underexploited, proper attention to its fishery management is necessary if the fish is a strong substitute for another popular fish species in the market.

Biogenic and volatile amine-related qualities of three popular fish species sold at Kuwait fish markets

Three fish species commonly consumed in Kuwait were studied for their total volatile base nitrogen (TVBN) and biogenic amine composition during normal commercial activities at the fish markets. Samples of the fish species Zubaidi or silver pomfret ( Pampus argenteus), Hammour or orange–spotted grouper ( Epinephelus coioides), and Negrule or grunt ( Pomadasys kaakan) were analyzed using steam distillation and high performance liquid chromatography (HPLC) procedures. Fish samples collected in the morning had lower levels of TVBN, ranging from 25.9 mg/100 g to 30.2 mg/100 g compared with the range of 31.2 mg/100 g to 40.9 mg/100 g for samples collected in the evening. Among all three fish species, Zubaidi ( Pampus argenteus) showed the lowest TVBN content while Negrule ( Pomadasys kaakan) had the highest. Biogenic amine levels were also low in the fish species. The data suggest that fish handling practices at the fish markets in Kuwait do not result in significant abuse of fish temperatures, and that the amounts of volatile and biogenic amines produced during normal activities did not rise to levels indicating fish decomposition.

Fish as an indicator of aquatic environment: Multielemental neutron activation analysis of nutrient and pollutant elements in fish from Indian coastal areas

Fish is the main food in coastal areas and its analysis for toxic metals has been used as an indicator of the pollution status of the aquatic environment. Several different fish species from the three Indian coasts, Visakhapatnam in the east, Mumbai in the west and Mangalore in the south west and also inland freshwater fish from Nagpur in the central region for comparison were analyzed for up to 20 elements (As, Au, Ba, Br, Cl, Co, Cr, Cu, Fe, Hg, K, Mn, Na, P, Rb, Sb, Sc, Se, Sr, Zn) by instrumental neutron activation analysis (INAA). Dried fish samples in powdered form were irradiated with thermal neutrons in a nuclear reactor followed by high resolution gamma ray spectrometry at different intervals. Several Reference Materials (RMs) of biological origin were analyzed for quality assurance and data validation. Elemental contents in different fish species vary in a wide range depending on the species, its size, location, and aquatic environment. Fish from Mangalore showed highest mean contents of Cr (14.8 ± 29.9 µg g−1), Cu (1005 ± 643 µg g−1) and Sb (849 ± 888 ng g−1) whereas those from Mumbai exhibited highest Hg (2066 ± 2146 ng g−1) and P (20.3 ± 4.63 µg g−1) but lowest Cu (6.30 ± 3.10 µg g−1) contents. Fish from all the regions showed significant amounts of nutrient elements such as Na, K, P, Mn, Fe, Se and Zn as well as some pollutant elements (Br, Cr, Sb, Hg). No regularity in variation of elemental contents with the size was observed. Prawn (Panaeus latisulcatus), a popular fish species from four different regions showed wide variation in elemental contents of Cr, Mn, Fe, Zn, Se, P including toxic pollutants, Sb and Hg. An attempt has been made to calculate daily dietary intake (DDI) for some nutrient elements from Indian fish. Elemental data for Cr, Cu, Fe, Hg, Se, and Zn have been compared with those from other fish exporting countries.

Recovery and distribution of natural antioxidants (α-tocopherol, polyphenols and terpenic acids) after pan-frying of Mediterranean finfish in virgin olive oil

Samples of eight finfish representing the most popular fish species in Greece were pan-fried in virgin olive oil according to the Greek traditional culinary practice. Analyses for polyphenols, hydroxy pentacyclic triterpene acids (HPTA) and α-tocopherol were performed in the fresh and fried oils and fish. Polyphenols and HPTA were determined by GC/MS and α-tocopherol by HPLC. Nine polyphenols were determined in the frying oil samples; six of them were also found in fried fish. The terpenic acids oleanolic, maslinic and ursolic were also determined in frying oils and fried fish. No polyphenols and no HPTA were detectable in raw fish, while α-tocopherol was present in all samples. Besides water loss and oil absorption, pan frying caused the partial loss of all the antioxidants studied in the fried oils, as well as their enrichment in the fried fish. The overall retention of α-tocopherol in the fried oil and fish ranged from 30% to 80%, the respective values for polpyphenols and HPTA ranging between 51–87% and 46–88%. The polarity of the antioxidants studied, seems to affect to some extent their partition between the frying oil and the water-containing fish.

Using a popular pet fish species to study territorial behaviour

The colourful, vigorous territorial display behaviour of the Siamese fighting fish, Betta splendens, has great appeal for both pet enthusiasts and animal behaviourists. Their beauty, longevity, easy maintenance and rearing make them a popular pet and an ideal science laboratory specimen. This investigation utilises B. splendens to test for the adaptive significance of defending a living space. Such territorial behaviour increases survival and is expected when its benefits are greater than its costs. Students can test this hypothesis by quantifying the fish's responses to intruders under different conditions in timed trials. The exercises enable college preparatory and undergraduate students in biology and psychology courses to investigate how decision-making by territorial organisms balances conflicting survival needs. Sample student laboratory results are provided to facilitate data analysis in the classroom. B. splendens (n = 6) displayed less to small intruders than large intruders that pose greater risk of territory takeover; and they spent less time adjacent to small intruders when highly preferred prey were available. These behavioural responses exemplify how a territorial species can reduce the costs of defence without increasing the risks of losing the territory.

The influence of season on the lipid profiles of five commercially important species of Brazilian fish

This study aimed at determining the influence of season (summer and winter) the total lipid, fatty acid and cholesterol contents of five popular fish species: the sardine, Sardinella spp., the croaker Micropogonias furnieri (marine species), the curimbatá Prochilodus spp., the tilápia, Oreochromis spp. (fresh water species), and the seabob shrimp, Xiphopenaeus kroyeri. Total lipid analysis was performed by the dry column; fatty acids were determined by gas chromatography and cholesterol was determined by a colorimetric method. Statistical treatment of results showed that sardines collected during winter had the highest lipid contents (10.62). The sardine, the croaker, the tilápia and the curimbatá were not influenced by seasonality in terms of their total saturated and unsaturated acid contents. The highest contents of eicosapentanoic acid (3.02 and 1.87%) and docosahexaenoic acid (10.1 and 11.3%) were found in the sardine. The shrimp presented the highest cholesterol contents (165 mg/100 g in summer and 165 mg/100 g in winter).

Growth performance of Barbodes gonionotus (Bleeker) in intensively cultivated rice fields

Barbodes gonionotus (Bleeker) is a popular fish species in rice–fish culture. In Vietnam's Mekong Delta, the species is often grown in polyculture with Oreochromis niloticus (L.) and Cyprinus carpio L. In this study, we used the data of eight experiments into such polycultures at the Co Do rice–fish experimental station to look whether the rice stage or fish biomass had any effect on the specific growth rate (SGR) of B. gonionotus. The B. gonionotus net production figures varied from 1.7 to 547.7 kg/ha, while the SGR varied from 0.27% to 3.58% body weight/day. We found that SGR values did not depend on the developmental stage of the rice crop. However, the SGR values significantly decreased with increasing standing biomass (SB) of B. gonionotus, O. niloticus or wild fish. We concluded that intraspecific and interspecific competition is an important issue in B. gonionotus culture in rice fields. Besides this, SGR values were higher in the wet season and in plots with inorganic fertilizer or pig manure application.

Myofibrillar protein degradation of carp (Labeo rohita (Hamilton)) muscle after post‐mortem unfrozen and frozen storage

AbstractThe degradation of myofibrillar proteins of rohu carp (Labeo rohita (Hamilton)) muscle was analysed after post‐mortem storage. Muscle fillets were kept either unfrozen at 2 °C for up to 15 days or frozen at −8 °C or −20 °C for up to 6 months. A co‐ordinated histochemical, biochemical and electrophoretic study showed a differential response of the carp muscle, revealing clear degenerative/degradative changes specific to the post‐mortem storage temperatures. The myofibrillar protein fractions, namely myosin light chains and α‐actinin, showed degradative changes during the above storage conditions, whereas other protein fractions in the high‐molecular‐weight range fragmented to give lower‐molecular‐weight proteins. The importance of the post‐mortem storage temperature for controlling the degradation of the myofibrillar proteins was emphasised. This is the first report on this popular fish species, known for its culinary importance, showing that specific protein fractions of the myofibrils degrade during post‐mortem storage.© 2001 Society of Chemical Industry

Impact of the Venezuelan economic crisis on wild populations of animals and plants

Because of the relatively well-defined starting date of Venezuela's current economic crisis (early 1983), it provides an ideal model for exploring the effect of worsening economic conditions on biodiversity use. I focus on changing harvest intensities of wood, wildlife and fish, by comparing harvest patterns prior to and after the onset of the economic crisis (pre- and post-1983). Specifically, I analyze figures for (1) wood production, (2) ornamental fish exports, (3) commercial harvests of spectacled caiman ( Caiman crocodilus) and (4) capybara ( Hydrochaeris hydrochaeris), (5) national and (6) international illegal wildlife trade, and (7) Venezuela's fisheries. I also explore whether current resource use practices appear to be sustainable or not by concentrating on fisheries, as these have abundant data on both the annual per-species catch and the harvest effort. In general, the harvest of wood, wildlife and fish increased sharply after 1983 reaching previously unrecorded levels, growing at a higher rate than the human population. Also, the catch-per-unit effort of many popular fish species in local markets has declined, thus indicating an unsustainable harvest. Although more than one mechanism may explain these results, most of the evidence suggests that contraction of the economy led to increasing unemployment and the workforce shifted to natural resource exploitation as an alternative source of income and food. Regulating the growth of this largely informal and diffuse population of direct resource users will require innovative and creative policies both in Venezuela and other developing countries undergoing similar processes.

Bilingual Mail Survey Approach to Examine Seafood Consumption Practices among Hispanics Living in Metropolitan New York

Two bilingual mail surveys were used to assess seafood consumption habits of Hispanics living in metropolitan New York. Culturally sensitive survey instruments were developed through interviews with professionals, a site visit, a focus group, and personal interviews with representatives of the target audience. Questionnaires were mailed to households with Hispanic-sounding surnames randomly selected from the telephone directory. Response rates were 54% (Survey 1, n = 201) and 42% (Survey 2, n = 373), with more than half of the respondents answering the Spanish version of the questionnaire. Respondents to each survey represented more than 20 different countries of origin and a wide variety of socioeconomic characteristics. More than 80% of Survey 1 respondents ate some form of finfish at home at least once per month. Among the 97% of Survey 2 respondents who ate fish or shellfish, the mean seafood consumption in the past 2 weeks was 3.28 ± 2.15 times. Canned tuna and shrimp were the most popular fish and shellfish species consumed, and popularity of other species varied by country of origin. Data indicate that a bilingual mail survey approach and a food frequency instrument can be an effective means of gathering detailed information about food practices among a diverse Hispanic population.

Mercury levels in muscle of some fish species from the Dique Channel, Colombia.

Gold mining is an activity that has been increasing during the last ten years in Colombia. Most mining activities are carried out using mercury for gold amalgamation. In a recent publication we stated that in the Sur de Bolivar, the main gold mining zone in Colombia, the highest mercury concentration in hair was observed in fishermen. The Magdalena River, the largest and most important river in Colombia, receives all this contamination and carries it to the Atlantic Ocean through two means: The main river course and the Dique Channel. The Dique Channel is surrounded by many marshes, which are a major source of fish for nearly two hundred thousands people in northwestern Colombia. The goal of the present study was to determine, for the first time, the content of mercury in muscle tissue of the four most popular fish species purchased in some towns along the Dique Channel, to establish whether these concentrations fall within the WHO guidelines, and to identify those species which can be consumed with less risk. 11 refs., 1 fig., 2 tabs.