Pieces Of Fish Research Articles

High Hydrostatic Pressure Treatment of Finfish To Inactivate Anisakis simplex

High hydrostatic pressure has been demonstrated to be a useful technique for treating food to reduce the number of pathogenic organisms and to extend shelf life. Most research in this area has focused on bacteria. However, a concern in the sashimi (raw fish) industry is that nematode worms such as Anisakis simplex occur naturally in cold-water marine fish. The objectives of this research were to perform a pilot study to determine the effect of high hydrostatic pressure on the viability of Anisakis simplex larvae, commonly found in king salmon and arrowtooth flounder, and to evaluate the effects of high hydrostatic pressure on the color and texture of the fish fillets. Pieces of fish (ca. 100 g per bag) containing 13 to 118 larvae were exposed to pressures of up to 80,000 lb/in2 (552 MPa) for up to 180 s. The times and pressures required to kill 100% of the larvae were as follows: 30 to 60 s at 60,000 lb/in2 (414 MPa), 90 to 180 s at 40,000 lb/in2 (276 MPa), and 180 s at 30,000 lb/in2 (207 MPa). For all salmon treatments that killed 100% of the larvae, a significant increase in the whiteness of the flesh was observed. Although high hydrostatic pressure was effective in killing A. simplex larvae in raw fish fillets, its significant effect on the color and overall appearance of the fillet may limit its application to the processing of fish for raw fish markets.

Preparation and use of freshwater fish, rohu ( Labeo rohita) protein dispersion in shelf-life extension of the fish steaks

A process to enhance shelf-life of freshwater fish, rohu, on ice using combination treatment of coating the fish steaks with gel dispersion from the same fish and low-dose gamma irradiation is described. Washed pieces of freshwater fish, rohu were converted into gel by dilute acetic acid treatment. The gel was homogenized in water to a dispersion having 29 g/L protein, apparent viscosity of 1.0 Pa s and pH 3.5. Coating of fresh rohu steaks by dipping in the dispersion for 1 h or gamma irradiation at 1 kGy gave a shelf-life of 32 days in ice, in comparison to 20 days for the untreated steaks. Irradiation at 1 kGy of the dispersion-coated steaks enhanced their shelf-life to 42 days. Bleaching of the pink colour of the steaks by the treatment was prevented when one of either butylated hydroxy anisole or ascorbic acid was incorporated at 5 g/kg (w/v) in the dispersion.

An improved scheme for temperature calculations in food

In an earlier paper, an empirical approach was reported to calculate the surface film conductance during cooling of slab shaped fish pieces. It was demonstrated there that when this surface film conductance value was used for temperature calculations, improved results were obtained. During repeated calculations, surface film conductance values were found to be a function of temperature. A correlation was developed for variable film conductance, and this correlation was used instead of a constant value. This resulted in an excellent agreement between the calculated and measured temperatures.

Crescimento em Goniopsis cruentata (Latreille) (Crustacea, Brachyura, Grapsidae) em laboratório

The growth of the crab Goniospis cruentata (Latreille. 1803), was studied in the laboratory, through of the molt increment and intermolt period. A total of 86 crabs (48 males and 38 females) were collected in the ltacuruca's Mangrove in Mangaratiba's county. Rio de Janeiro. The crabs were maintened in the laboratory in four 1000 l tanks, with continuous water circulation during fifteen months. They were fed each two days with pieces of fish and fruits. The crabs varied in size from 19.3 to 56.0 mm in males and 23.3 to 48.8 mm in females. The males presented until four molts during the experiment and the females until six molts. The molts oceurred during ali the months. The mean percentage of molt increment was 6.1 ± 2.7%, for both sexes and it decreased with the animal growth. The relation between the molt increment and the carapace width can be expressed by the equation IM = -0.32LC + 18.26 (r = -0.82). This relation didn't show any significative difference between the sexes. The mean intermolt period was of 87.6 + 37.3 days in male crabs and 97.3 ± 27.6 days in females. The growth was contiguous, through successive molts, although the increment was reduced with animal size. The intermolt period was proportional to the animal size increase, however males with autotomy of limbs had the intermolt period reduced.

Kinematic Analysis of Suction Feeding in the Nurse Shark, Ginglymostoma cirratum (Orectolobiformes, Ginglymostomatidae)

Inertial suction feeding is known to occur in some sharks, but the sequence and temporal kinematics of head and jaw movements have not been defined. We investigated the feeding kinematics of a suction feeding shark, the nurse shark Ginglymostoma cirratum, to test for differences in the timing and magnitude of feeding components with other shark taxa when sharks were fed pieces of bony fish. Thirteen kinematic variables were measured from high-speed video recordings. Food capture in this species consists of expansive, compressive, and recovery phases, as in most other sharks, but there is little or no cranial elevation. Mean time to maximum gape (32 msec) is the fastest recorded for an elasmobranch fish. Other relatively rapid events include mandibular depression (26 msec), elevation (66 msec), and total bite time (100 msec). Buccal valves assist the unidirectional flow of water into the mouth and out of the gill chambers. Food capture under these experimental conditions appears to be a stereotyped modal action pattern but with significant interindividual variability in timing of kinematic events. Ginglymostoma cirratum exhibits a suite of specializations for inertial suction feeding that include (1) the formation of a small, anteriorly directed mouth that is approximately round and laterally enclosed by modified labial cartilages; (2) small teeth; (3) buccal valves to prevent the backflow of water; and (4) extremely rapid buccal expansion. Sharks that capture food by inertial suction have faster and more stereotyped capture behavior than sharks that primarily ram feed. Inertial suction feeding, which has evolved multiple times in sharks, represents an example of functional convergence with inertial suction feeding bony fishes.

Feeding behaviour of free-ranging penguins determined by oesophageal temperature.

Sea birds play a major role in marine food webs, and it is important to determine when and how much they feed at sea. A major advance has been made by using the drop in stomach temperature after ingestion of ectothermic prey. This method is less sensitive when birds eat small prey or when the stomach is full. Moreover, in diving birds, independently of food ingestion, there are fluctuations in the lower abdominal temperature during the dives. Using oesophageal temperature, we present here a new method for detecting the timing of prey ingestion in free-ranging sea birds, and, to our knowledge, report the first data obtained on king penguins (Aptenodytes patagonicus). In birds ashore, which were hand-fed 2-15 g pieces of fish, all meal ingestions were detected with a sensor in the upper oesophagus. Detection was poorer with sensors at increasing distances from the beak. At sea, slow temperature drops in the upper oesophagus and stomach characterized a diving effect per se. For the upper oesophagus only, abrupt temperature variations were superimposed, therefore indicating prey ingestions. We determined the depths at which these occurred. Combining the changes in oesophageal temperatures of marine predators with their diving pattern opens new perspectives for understanding their foraging strategy, and, after validation with concurrent applications of classical techniques of prey survey, for assessing the distribution of their prey.

Freshwater crayfish farming technology in the 1990s: a European and global perspective

This paper aims to describe the state of crayfish farming technology in the USA, Australia and Europe, and to discuss some of the prerequisites for this industry. Data from Europe are partly based on replies from a questionnaire sent out to scientists in all European countries. For other parts of the world, the crayfish literature has been reviewed and data from the August 2000 meeting of the International Association of Astacology are also included. Issues addressed in this review are cultivated species, production and productivity figures, production technique with regard to enclosures, reproduction and feed items, disease problems, predators, pond vegetation and water quality.Fewer than a dozen crayfish species are cultivated. The most attractive ones for culture and stocking in natural waters have been transferred to more than one continent. Pond rearing techniques predominate in all countries, and the technology required to achieve the spawning and rearing of juveniles is relatively simple. Pieces of fish, carrots and potatoes are frequent supplementary feed items; plants, cereals, pieces of meat, zooplankton and pellets are also common. Diseases are not usually a major concern, except in Europe where the American plague fungus, Aphanomyces astaci, has eradicated many European crayfish populations. Predators identified as common include insects and amphibians, as well as fishes, birds and mammals. Many water macrophytes are common in crayfish farms. These may either serve a useful function or cause problems for the crayfish farmer. Water temperature is the crucial factor for crayfish production. Water parameters such as pH and certain inorganic ion concentrations may also be of concern. Acidic waters that occur in some areas are generally detrimental to crayfish.The total yield from crayfish production from farming and fishery is in the order of 120 000–150 000 tonnes, more than four times the quantity given by FAO statistics. The largest crayfish producer is the Peoples’ Republic of China, followed by the USA (70 000 and 50 000 tonnes in 1999, respectively). Of the quantity produced in the USA in 1999, about 35 000 tonnes was farmed. The yield in Europe was about 4500 tonnes in 1994, and of this quantity only 160 tonnes came from aquaculture. There are no official statistics for crayfish fishery production in Australia, but about 400 tonnes came from aquaculture in 1999.

Induction of Emesis by the Sodium Channel Activator Veratrine in the Lesser Spotted Dogfish, Scyliorhinus Canicula (Chondrichthyes: Elasmobranchii)

This study provides the first quantitative description of the emetic reflex (vomiting) in the dogfish (Scyliorhinus canicula) by using veratrine HC1 (lOmgkg−1, i.p.), the sodium channel activator as a stimulus. Vomiting occurred within 10 min of injection. The most notable features of the response in the correct temporal sequence were: (i) head shaking with wide gaping of the mouth; (ii) lowering of the ventral buccal cavity and expansion of the pharyngeal cavity; (iii) contraction of the gill arches, the buccopharyngeal musculature and lowering of the jaw rapidly followed by the expulsion of gastric contents (pieces of fish). The expulsion sequence (ii and iii) took ~ 1 s. The significance of the vomiting reflex in the dogfish is discussed in terms of its protective function and as a component of normal feeding to periodically eject indigestible food residues.

Food of Flesh-footed Shearwaters Puffinus carneipes Associated with High-seas Driftnets in the Central North Pacific Ocean

SummaryWe examined digestive tract contents and stable nitrogen isotope ratios in breast muscles of Flesh-footed Shearwaters Puffinus carneipes associated with high-seas driftnet fisheries in the central North Pacific Ocean. Small fish, Lanternfish (Myctophidae) and Pacific Saury Cololabis saira, were the principal prey found in the digestive tracts. Pieces of unidentified fish, possibly Pacific Pomfret Brama japonica, and shredded squid tissue, mostly Neon Flying Squid Ommastrephes bartrami, in the digestive tracts indicate scavenging at driftnet fishing operations. Although soft-bodied animals such as Velella sp. were rare in the digestive tracts, low stable nitrogen isotope values (δ15N) suggest Flesh-footed Shearwaters feed heavily on such low trophic level animals.

Predation on jellyfish by the cephalopod Argonauta argo

Predation on jellyfish by the cephalopod Argonauta argo

Response of Pheidole morrisi to two species of enemy ants, and a general model of defense behavior in Pheidole (Hymenoptera: Formicidae).

Response of Pheidole morrisi to two species of enemy ants, and a general model of defense behavior in Pheidole (Hymenoptera: Formicidae).

Lipid content and fatty acid profiles of various deep‐fat fried foods

AbstractForty‐one brands of nine different types of snack and convenience foods were purchased from food stores and fast service restaurants in the Sacramento area of California. All samples had been prepared by deep‐fat frying. They included potato chips, corn chips, tortilla chips, cheese chips, cheese puffs, cake donuts, french fries, chicken pieces and fish pieces. These samples were analyzed in duplicate for total fat and fatty acid composition. The total lipid content of each type of food varied among different commercial sources; the average percentages were as follows: potato chips, 40; cheese puffs, 38; corn chips, 35; cheese chips, 25; tortilla chips, 24; cake donuts, 22; chicken thighs, 14; french fried potatoes, 14, and fish pieces, 10. The fatty acid profiles of the total lipids in several brands of potato chips were relatively constant. The fatty acid profiles of the total lipids in the corn and cheese snack foods varied widely. Fatty acid compositions of donuts, chicken and fish pieces and french fries were influenced by the amount and fatty acid profile of the lipids in each uncooked food, as well as by the composition of the cooking fat.

Stomach content analysis of the sea barbel,Galeichthyes feliceps(Valenciennes in C & V), from the Swartvlei system, southern Cape

The diet of the sea barbel, Galeichthyes feliceps, in the Swartvlei estuarine system was investigated during the period April 1979 to March 1980. The stomachs of 393 specimens (TL 13,5 to 46,0 cm) were examined. The sea barbel appears to be a bottom feeder with the crown crab, Hymenosoma orbiculare, forming its main prey throughout the system. Unidentified pieces of fish and the tube- dwelling amphipod, Grandidierella lignorum, were respectively the second and third most important food items. The feeding habits of most adult male sea barbel were markedly affected by the breeding season, since during this time they were carrying developing eggs in their mouths and apparently did not feed.

Dolphin biosonar detection in clutter: Variation in the payoff matrix

An Atlantic bottlenose dolphin (Tursiops truncatus) was trained to detect targets in the presence of interference induced by a clutter screen. The screen consisted of forty‐eight 5.1‐cm‐diam cork spheres spaced 15.2 cm apart and arranged in a rectangular array. Hollow aluminum cylinders having the same outer diameter and wall thickness and three different lengths were used as targets. Only one target was presented per target‐present trial and it was placed in the plane of the clutter screen at its midpoint. The payoff matrix was manipulated by changing the amount of reinforcement (number of pieces of fish) for correct detections and rejections. In terms of the ratio of correct detections to correct rejections, the payoff matrix was varied over four values—1:1, 4:1, 8:1, and 1:4. As the payoff matrix increased from 1:1 to 4:1 and 8:1, the dolphin became progressively more liberal in reporting on the presence of a target with a subsequent increase in both the correct detection and false alarm rates. However...

Effects of food and shelter on aggressive activity in the crayfish Orconectes rusticus (Girard)

ABSTRACT In a simplified laboratory environment, aggressive activity (threats, strikes, fights) of Orconectesrusticus declined with increasing availability of both shelter and food. Shelter and food interacted to determine overall aggressive activity; however, in general, shelter reduced aggressive activity more than did food over the 42 h duration of our treatments. Preferred food (fish pieces) reduced activity more than did less preferred food (Tetramin). Individual crayfish varied substantially in amount of aggressive activity. Overall, threats accounted for 16% of aggressive interactions, strikes for 46%, and fights for 38%; proportions were relatively constant among most treatments and between day and night.

Study on the use of halophilic bacteria in production of fish sauce.

Accelerated production of fish sauce by adding some halophilic bacteria was studied. Sardines (200g) were cut into 2-3cm pieces, uneviscerated and well mixed with 50g of salt. Bacillus C1 and Bacillus C6, isolated from Chinese fish sauce and strain No. 3-19-1, isolated from sand of Kinko Bay were cultured in Sehgal and Gibbons Complex (SGC) medium with 3M NaCl and pH 6.6-6.8. The bacteria were harvested on the day of their maximal growth. Each of the bacterial slurry (12.5ml) was added to the mixture of fish pieces and salt and put into glass jar. To the control without bacteria, 12.5ml of solution containing NaCl and MgSO4, the concent-rations of which were identical with the cultural medium was added. Progress in proteolysis of fish sauce was investigated by determining pH, total soluble nitrogen content, amino-type nitrogen content and volatile basic nitrogen content of fish sauce throughout the fermentation process. Bacillus C1 showed remarkable effect on accelerating the process. The liquefaction step could be finishedwithin 3 months. Ripening at various conditions was investigated and it was observed that volatile organic acids appeared within one month in the sample ripened at 30°C under reciprocal shaking. Free amino acids of fish samples were determined and it was recognized that there was no great difference in free amino acid profile of control and that of bacteria-added samples.

Distastefulness as a defense mechanism inAplysia brasiliana(Mollusca: Gastropoda)

The biochemical literature on the toxicity of various species of Aplysia is reviewed to indicate that Aplysia are probably not toxic to predators under natural conditions. The possibility that Aplysia avoid prrdation by being distasteful is examined by offering various portions of Aplysia brasiliana and pieces of fish to sea gulls. Gulls are shown to find all parts of Aplysia more distasteful than fish, even fish soaked in a mixture of Aplysia blood, mucus, and ink. Ink gland, gill, and epidermal portions are shown to be significantly more distasteful than other portions, even the midgut and opaline glands, sites of compounds which can be toxic when injected. Distastefulness as a mechanism for avoiding predation and the possible function of the ink gland are discussed in light of these findings and current literature.

Some aspects of the biology of Dermestes maculatus Degeer (Coleoptera, Dermestidae) in dried fish

The development of Dermestes maculatus Deg. in dried fish has been studied under uncontrolled laboratory conditions. Females laid eggs within 12 hr of copulation, and oviposition was improved by the presence of free water. Hatching occurred about 48 hr after oviposition. The characteristic appearance of the egg and the changes that occurred during incubation and hatching are described. Larval development was completed in 33·5 days during which seven moults occurred and a body length of 14 mm was attained. Larval life was prolonged by crowding. When intact pieces of fish were available, the last instar larva bored into one of them and pupated within the hardened larval skin, but when ground fish was provided, a quiescent prepupal stage was observed. The adult emerged about 11 days after the last instar larval stage, irrespective of the mode of pupation.

Dehydration of membrane-coated foods by osmosis.

AbstractPreliminary studies have shown that pieces of fruit, meat, fish, and whole shellfish can be dehydrated osmotically. Fifty percent invert sucrose was used as a solute; edible semipermeable membranes maintained osmotic differential and reduced solute contamination of the product. The greatest weight loss was observed with component items of high molecular weight such as meats and fish. Some of the products when re‐hydrated show a marked similarity to the fresh food. Calcium pectate membranes gave the best results.

Studies on the adult and diplostomulum of Diplostomum (Dolichorchis) leonensis (Strigeida: Trematoda).

Large number of fishes of the family Cryprinodontidae collected from a stream at Hastings, Sierra Leone, were found with a diplostomulum encysting on the skin and in the musculature.Infected pieces of fish were fed to day-old chicks and cattle-egrets, and adult stages of a worm, considered to be new species and namedDiplostomum(Dolichorchis)leonensis, were obtained.Morphological details of the diplostomulum and the adult worm are described.The author wishes to express his gratitude to Dr G. Dubois for his interest and advice in connexion with the study, to Miss M. R. Coker who prepared the diagrams; and to Messrs F. Deen, T. Alhassan and M. Seisay for technical help.