Reproductive cycle, maturation mode, and body size and age at maturity of the hexagrammid fish, Hexagrammos agrammus, at Aburatsubo in central Japan were examined by analyzing the seasonaltrends in gonadosomatic index (GSI) and gonadal maturity as revealed by histological observations.Gonads were assigned to the following 5 phases of maturity: (0) immature phase, (I) maturing phase, (II) early spawning phase, (III) late spawning phase, and (IV) recovery phase, based on conditions ofthe most developed oocytes and the presence of empty follicles or atretic oocytes for females, and onthe presence and the amount of spermatocytes or sperm for males. Females appeared to be multiplespawners, i.e., spawning more than oncein a spawning season, judging from the coexistence of oocytesat the pre-mature stage and empty follicles in mature ovaries. Spawning, corresponding to maturity phases II and III, occurred from late November to late January. All females aged 1+and older matured.Smaller 0+females less than 105 mm in standard length (SL)did not spawn within the current spawningseason, but larger fish (≥105mm SL) spawned in the season. Testes of all males were ripe at age 0+ (≥88mm SL), but the firstegg-guarding age was 1+ (121mm SL).

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Oxygen consumption in the developmental larvae of the flounder Paralichthys olivaceus was measured by an improved water bottle method. Syringes were used as a volume variable respiration chamber. Significant differences were observed in mass specific oxygen consumption among the early morning measurement at 10-day intervals. The formula M=aW^b was adopted, where M and W were metabolic rate and body mass. Two deflection points were detected in the metabolic exponent (b). Metabolic exponent for the larvae on the third phase was calculated to be 0.7135. Mass-specific metabolic rate (M/W) of the larvae on the first phase decreased withan increase of the body mass, however, there wa no evident relationship betweenthe morphological changes and metabolic rate.

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Genetic differentiation among 12 populations of Japanese char Salvelinus leucomaenis were examined based on allelic frequencies at 32 isozymic loci. Cluster analysis based on Nei's genetic distance usig UPGMA method classified the 12 populations into 5 groups that are Hokkaido-Tohoku, Tohoku-Kanto, Niigata-Gifu, Ishikawa, and Shiga groups. The five geographic groups showed the significant characteristics of allelic distribution.
The distance tree constructed by the Neighbor-Joining method based on Nei's genetic distance indicates good agreement with the cluster using UPGMA method. In the construction of the distance tree by Neighbor-Joining method, Tohoku-Kanto group joined finally with the Niigata-Gifu group in the center of the distance tree. This suggests that the Tohoku-Kanto group might be near to the original Japanese char.

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Testicular activity, as represented by the amount of each type of testicular germ cell in the seminal lobules, and the serum levels of three major male teleost steroids-testosterone (T), 11-ketotestosterone (11-KT), and 17α, 20β-dihydroxy-4-pregnen-3-one (17α, 20β-DP) -were investigated during the daily spawning cycle of the male Japanese flounder Paralichthys olivaceus.
B-type spermatogonia and spermatocytes increased in number from the lowest level at 22:00 (186 cells/lobule), and peaked at 10:00 (292 cells/lobule). The number of spermatozoa increased from 14:00 (370cells/lobule) and peaked at 22:00 (782 cells/lobule). In contrast, spermatid numbers decreased from 14:00 (579 cells/lobule) and showed the lowest level at 22:00 (348 cells/lobule). These results indicate that spermatogenesis (spermatogonial proliferation, the formation of spermatocytes and spermatids) occurs between 22:00 and 10:00, and spermiation (release of spermatozoa into the lobular lumen from the cysts) occurs between 14:00 and 22:00. Thus, spermatogenesis and spermiation occur on a daily basis in the male Japanese flounder. Serum T and 11-KT levels showed no significant fluctuation throughout the day. Serum 17α, 20β-DP was maintained at a low or undetectable level throughout the experimental period, but showed a surge (110 pg/m/) at 22:00. This short-lived 17α, 20β-DP surge corresponded to the peak of spermiation. This study demonstrates, therefore, the existence of a diurnal periodicity in (1) spermatogenesis and spermiation, and (2) 17α, 20β-DP production.

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The efficacy of three different algae (Ascophyllum nodosum, Porphyra yezoensis, and Ulva pertusa) were compared in fingerling red sea bream Pagrus major. Oregonmoist diet containing 5% of algae meal were fed for 41 days and the effects weremonitored in terms of growth, feed efficiency, and body composition.
Feeding algae commonly elevated body weight grain, and tended to increase feed efficiency and muscle protein deposition. Algae-fed groups were higher in liver glycogen andtriglyceride accumulation in muscle. Feeding Porphyra showed the most pronouncedeffects on growth and energy accumulation, followed by Ascophyllum and Ulva. Theresults suggest the practical efficacy of using algae as a feed additive for theeffective use of nutrients in cultured fish.

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The incorporation and retention of water-borne strontium in otoliths (asterisci and/or lapilli) were studied using the freshwater goldfish Carassius auratus. The effects of strontium concentrations, temperature, and 17β-estradiol were examined using atomic absorption spectrophotometry and X-ray analysis. Water-borne strontium (0.1, 1.0, and 10.0 mgl^-1) was incorporated into otoliths (asterisci) in a concentration-dependent manner after an 88-day exposure, but a high concentration of 10.0 mgl^-1 rather depressed the rate of incorporation. Similar results were seen with Sr-Ca ratios in plasma and otoliths. The strontium incorporatedinto otoliths remained after 92 days in nonstrontium-enriched water, while that in scales and ribs decreased. Otolith (lapillus) Sr-Ca ratios distinctly differ d between freshwater (Sr/Ca=2.6×10^-3) -and diluted (1/9, 1/6, and 1/3) seawater (25×10^-3 on an average)-reared groups, but no difference was found among the seawater groups. These ratios linearly increased with temperatures between 16 and 24°C in asterisci (r=0.65). However, they somewhat decreased at 28°C. A single administration of 17β-estradiol resulted in hypercalcemia and decreas d strontium incorporation into the lapillus but not in the asteriscus. The lapi lus contained 12 times more strontium than the asteriscus.

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This paper presents a new approach to distinguishing an observed length distribution into each of those by age using the genetic algorithms. The length distribution of each age is assumed to follow a normal distribution with mean T_x, and variance σ²_x. Three pieces of model independent biological information are incorporated instead of assuming a growth function, and then analyze the undistinguishably mixed length-frequency into each of those by age. The first isthat the number of age class is known. The second and the third are that the ranges of themean length and variance of each age class are roughly known from the other biological studies. For the latter parameter, two models are examined. Artificial data and actual sardine data are analyzed to know the efficiency of this approach. The efficiency depends on the width of ranges given for the mean length and standard deviation of each age class which were used to estimate the parameters mentioned above. However, the results showed even though the width of the ranges werenot so small, both models of this approach worked well to distinguish total length distribution into each of those by age.

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Trace element concentration in fish otoliths was analyzed by particle induced X-ray emission (PIXE). Otoliths were collected from juvenile red sea bream, Pagrus major, in accordance with their growth stage from 19 days after hatching to 106 days. Individuals were reared in three different sea-farming stations: Momoshimaand Hakatajima stations located along the western Seto Inland Sea and Miyazu station along the western coast of the Sea of Japan. Seawater temperatures were continuously measured using micro-data logger type thermometers at 1.5 m depth fromJune to August 1993 in aquaculture basins during fish rearing periods at 20-minute or one hour intervals. Fluctuations of temperature at the three stations showed different positive thermal gradients and different mean temperatures from the beginning to the end of the experiment. Otolith surfaces without cutting or polishing werethen exposed in air to a 1.16 MeV proton beam. X-ray spectra detectedwith a lithium-drift silicon Si(Li) detector indicated that reared fish tolithscontained some trace elements of 2+ valence such as Mn (40-64 ppm), Fe (169-246 ppm), Zn (61-120 ppm), and Sr (1634-2330 ppm). We ascertained that trace elementsin the surface of otoliths can be detected accurately to several tens ppm by using PIXE. Concentrations of these trace elements appear to increase in proportionto temperature.

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The arrangement of carp α-and β-globin genes were examined at the nucleotide sequence level. Then, the nucleotide sequence of 1, 249 base pairs (bp) for the 5' untranslated region of the carp β-globin gene was determined. This region showed a high homology with the previously reported carp a-globin gene No. 7. The overall nucleotide sequence homology of these two clones was 96.7%. DNA sequencing analysis indicated that the 1-globin gene closely linked the α-globin gene. Additionally, the close linkage of carp α-and β-globin genes was proven by Southern blot hybridization and PCR amplification. The direction of the transcription of the α-and β-globin genes was the opposite. The length between the a-and β-globin gene translation initiation site was 792 bp and the nucleotides of this region was high in of A and T contents. Carp α-and β-globin genes show unique symmetrical arrangement.

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This series of studies on nutritional energetics in carp and rainbow trout aims to provide basic data necessary for standardization of feed quality evaluation for fish in captivity. At the outset, endogenous nitrogen excretion (ENE) through the gills and in the urine was determined by feeding a non-protein diet which is essential for calculation of metabolizable energy.
The amounts of ENE in carp of 21-289g were 5.6-9.3mg/100g body weight/day anddecreased with increase of fish body weight and with decrease of water temperature. The rates of ENE were 10.0-15.7mg/100g BW/day for carp weighing below 20g. The ENE rates in rainbowtrout were proportional to water temperature, ranging from 6.6mg at 14°C to 12.4mg at 21°C (9.0mg on average).
Secondly, to determine non-fecal energy losses carp or rainbow trout weighing more than 100g were fed four kinds of experimental diets. There were no marked differences in the non-fecal losses among the fish fed the same diet once or three times daily at almost the same feeding levels. The proportion of energy lost through non-fecal wastes seems to be not so influenced by temperature.

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A simple, low-cost and efficient bioreactor system for production of anti-infectious hematopoietic necrosis virus (IHNV) substances by bacteria isolated from aquatic environments was devised on a laboratory scale. Whole living cells of anti-IHNV substances producing bacteria, Pseudomonas sp. 51 BBW-29 and Alteromonas sp. 48 HS-27, were immobilized in calcium alginate beads prepared by 1% sodium alginate, 0.45M CaCl₂, and C₂Y or MC₂Y broth. Eighteen g of the beads were packed into a 25 ml reaction column and incubated at 15°C for 5 days in a circulating broth medium at a flow rate of 0.35 ml/h. After activation of the immobilized bacteria, the beads were incubated in a continuous flow of fresh broth with intermittent exposure to air. In the beads incubated under these conditions, the immobilized bacteria grew well at the gel surface and high viability of approximately 10¹⁰ CFU/bead was retained for at least 6 days from day 8 to 14. During 31 days of the experiment with the bioreactor system, the highest production was 69.3 ΔIHD₅₀ for Pseudomonas sp. 51 BBW-29 (at 14-17 days incubation) and 48.0 ΔIHD₅₀ for Alteromonas sp. 48 HS-27 (at 8-11 days incubation), which were 2.5 and 2.7 times higher than those of conventional batch culture (27.3 and 18.0 ΔIHD₅₀ for the two strains at 2-5 days incubation). The immobilized bacteria continuously produced high levels of anti-IHNV substances for 15 days (day 5-20).

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According to the Cypridina chemiluminescence method for measuring rate constantsbetween superoxide (O^-₂) and antioxidants established in our previous report, the reaction constants between O^-₂ and metallo-chlorophyllins or chlorins e₆, whose oxidative stress relief activities at ischemiareperfusion were inspected, were measured by quenching experiments of chemiluminescence of a Cypridina luciferin analogue, 2-methyl-6-phenyl-3, 7-dihydroimidazo [1, 2-α] pyrazin-3-one (CLA), in 25mM buffer solutions (pH 7.0) at 25°C. The results were compared with known data in the literature, and showed that the present method can be used to measure reaction activities of antioxidative samples even if fairly unstable. The results show that oxidative stress relievers have strong antioxidative activity against in aqueous solutions.

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Eight neuroactive molecules were examined for their larval metamorphosis-inducing activities in three species of serpulid polychaetes, Hydro ides ezoensis, Pomatoleios kraussii, and Ficopomatus enigmaticus. L-3, 4-dihydroxyphenylalanine (L-DOPA) and D-DOPA induced larval metamorphosis in all species, while dopamine did not. Epinephrine and norepinephrine also inducedlarval metamorphosis in H. ezoensis and P. kraussii. Approximately 58-67% of H. ezoensis larvae metamorphosed when exposed to L-DOPA at concentrations of 3×10^-6_-1×10^-5 M, while D-DOPA induced 43-44% metamorphosis at 2×10^-5_-3×10^-5 M. Dose-dependent induction by L-DOPA and lowactivity of the enantiomer suggest the possibility of receptor mediation in metamorphosis induction by L-DOPA. Because of the delayed reaction and the absence of tube formation, L-DOPA is thought to act not on epithelial chemoreceptors but to affect other pathways of metamorphosis. Competence for metamorphosis in H. ezoensis by L-DOPA fluctuated with larval age and two peaks were observed on the 5-6 th and 9-11 th days after fertilization.

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This research investigated sarcoplasmic protein (Sp-P) contribution to the thermal gelation of meat paste and myofibrillar protein. The Sp-P was recovered by an ultrafiltration unit from the wash water of milkfish meat paste preparations. Washed meat paste showed gel strength 1.4-2.0 times that of unwashed paste. This may be caused by the concentration effect of myofibrillar protein. Adding Sp-P increased gel strength in both washed and unwashed meat pastes. The larger the amount of Sp-P added, the stronger the effect. Suwari occurred at 40-50°C and modori occurred at 60-70°C for milkfish meat pastes irrespective of the addition of Sp-P. Sp-P addition (10mg/g) caused suwari indices to change from 41 to 51, and modori indices from 37 to 33. These results show that the additionof Sp-P improves thermal gelation, has a promotive effect on suwari and a restrictive effect on modori.

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The contribution of transglutaminase (TGase) to the setting of fish flesh paste was studied using TGase-free actomyosin (AM) from five fishes. Sarcoplasmic proteins (SP) were extracted from each fish and one part of them was treated with N-ethylmaleimide in order to inactivate TGase contained in them (NEM-SP). The addition of SP to the AM paste promoted the cross-linking of myosin heavy chain during its setting and increased the breaking force of resulting suwari gel. In the breaking force, the gel added with SP was higher than the one added with f-SP by 40% for Alaska pollack and sardine, 20% for common horse mackerel and flounder, and less than 10% for Spanish mackerel. From the result and our previous study, it is presumed that TGase increases the breaking force of the suwari gel from the fish flesh paste nearly by a few ten per cent.

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Distribution and genus/species composition of histamine (Hm) -decomposing bacteriaduring thestorage of common mackerel meat at 5°C and 30°C were examined. Pseudomonas I/II, Micrococcus, Moraxella and Corynebacterium-Arthrobacter were detectedasHm-decomposing bacteria at the beginningof the storage. Pseudomonas I/II becamedominant with the progress of spoilage at both 5°C and 30°C. These Pseudomonas I/II, which were identified as Pseudomonas putida, seemed to play a major role inthe decomposition of Hm accumulated during the storage of the fish muscle.

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Based on the result that the water velocity of a rearing pond greatly influenceslipid mobilization, this paper examines the nature of intraperitoneal fat body (PF) on ayu Plecoglossus altivelis reared ina low water velocity (4cm/s) and high water velocity (55cm/s) pond for 58 days.
Water velocity scarcely influenced lipid content of IPF, but high water velocity increased thelipid/DNA ratio which isused as an index of adipose cell size. Fatty acid and triglyceride compositionswere not influenced by water velocity.
Although water velocity had no effect on serum fatty acid level, the free fatty acid level in IPF wasslightly higher at thehigh water velocity. In vitro lipolysis activity was defined as the level of fatty acidsreleased from an IPF slice during 120 min incubation. The high water velocity increased the activity, despite the difference in sensitivity to lipolytic hormones. Rearing in high water velocities induced highlipolysis activity to adapt to high energy requirements.

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The activity of erythrocyte 5-aminolevulinic acid dehydratase (ALA-D) of carp Cyprinus carpio wasmeasured under a variety of lead exposure conditions. A two-week exposure of carp to water leadconcentrations of 10-1, 000 ppb strongly inhibited their ALA-D activities with increasing water leadconcentrations. When carp were exposed to water lead concentration of 100 ppb, depressed activity ofALA-D became visible after only 2 days, and this activity became even less with increasing exposureperiods. The ALA-D activity of carp after the fish were transferred from water lead concentration of 200 ppb to lead-free water recovered to only 50% of the value in the control fish even after four weeks. Therefore, these characteristics concerning ALA-D in carp blood indicate that this enzyme is useful asa short-term indicator of lead pollution in the fresh waters of Japan.

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This study was conducted in order to improve a method for determining the activity of 5-aminolevulinic acid dehydratase (ALA-D) in the blood of carp Cyprinus carpio using the reagent without HgCl₂. Seven % TCA solution was used to terminate the enzyme reaction of ALA-D and to removeSH groups which impede the coloring reaction with the Ehrlich reagent. HgCl₂ was also removed fromthe Ehrlich reagent. In the case of the modified method which did not use HgCl₂, the reaction mixturewas left to stand for 10 min after being at first immediately mixed three times, then, after 10 min andthirdly, after 20min following the addition of the TCA solution to the reaction mixture. When the bloodALA-D activities of carp exposed to various concentrations of lead in water were determined by thepresent method, the levels of ALA-D activities were found to be much the same as the previous methodusing HgCl₂.

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High polarity products (HPP) are observed to increase dramatically during the embryogenesis of Macrobrachium rosenbergii; in this investigation, their identity was examined employing high performanceliquid chromatography (HPLC) and radioimmunoassay (RIA). 20-Hydroxyecdysonoic and ecdysonoicacid were seen to comprise over 70% of total HPP immunoreactivity. Conjugates of 20-hydroxyecdysone, inokosterone, and ecdysone accounted for up to 25% of HPP immunoreactivity, and 20, 26-hydroxy-ecdysone comprised less than 5%. Therefore, as development proceeds, the acidic 26-oic derivativesbecome the dominant ecdysteroid species. It has been postulated on the basis of this investigationthat 26-oic derivative formation is the major route of ecdysteroid inactivation; concommittantlyincreasing 20-hydroxyecdysone and 20-hydroxyecdysonoic acid titres and observed low quantities of 20, 26-dihydroxyecdysone suggest the rapid conversion of active hormones to 26-oic derivatives. Conjugate formation may also be a route of ecdysteroid inactivation. These pathways may be importantin controlling the titres of active ecdysteroids within the egg, and are possibly manifested by the ac-cumulation of metabolites during embryogenesis.

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Species-specificity of suwari gel-formability was examined on the pastes from various fish fleshes, in which transglutaminase (TGase) was inactivated. The gels were prepared by setting the pastes withand without adding polyol (4% sucrose-4% sorbitol) and N-ethylmaleimide (NEM) at 35°C for 1.5 and3 h, respectively. Thebreaking force of the gels was high in the order of red barracuda, jack mackerel. hairtail, Spanish mackerel, stone flounder, Alaska pollack, filefish, bottom threadfin bream, salmon, andcod. The TGase activity of the pastes was generally higher for those fish whose gels showed higherbreaking force. As setting progressed, cross-linked myosin heavy chain (cross-linked MHC) in the pastes also increasedremarkably in those fish whose gels showed a higher breaking force.

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Changes in the glycogen and triglyceride levels of the muscle and mid-gut gland of fed and starvedjuvenile disk abalone Haliotis discus discus were examined over a 70 day period. In the starved treatment, the glycogen and triglyceride contents in both tissues were consumed within 30 days, and from then, the water solubleprotein content decreased. The mortality ratio increased after40 days and reachedapproximately 50% on the 70 th day, suggesting that juvenile Haliotis discus discus are able to resistcomparatively long-term starvation. However, abalones which were starved for more than 30 days wereconsidered to show high physiological stress, that is with a reduction of behavioral activity and increaseof mortalityratio due to degradation of water soluble protein.

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Eighty-three of 200 bacterial strains isolated from seawater sampled at two locations near a Laminaria culture farm in Hokkaido decomposed Laminaria japonica fronds in a simple screeningtest after 4 weeks of incubation at 20°C. The proportion of L. japonica frond-decomposing bacteria (LDB) to the total isolates was 54% in water sampled at Kushiro and 29% in that sampled at Hakodate.The LDB were commonly identified as belonging to the Alteromonas group. Most of the LDB were characterized as alginate decomposers, and showed decomposing ability against Eisenia bicyclis and Ecklonia cava fronds. Bacteria capable of decomposing brown algaefronds were abundantly distributedin waters where Laminaria vegetates.

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A cysteine protease was purified from the white muscle of common mackerel Scomber japonicus by ammonium sulfate fractionation and successive column chromatography. The final enzyme preparation appeared to be homogeneous on polyacrylamide gel electrophoresis. The purified enzyme hydrolyzed Z-Arg-Arg-MCA, but not Z-Phe-Arg-MCA. The molecular mass of the enzyme was estimated to be 55 kDa by gel filtration and have a pH optimum of 5.5. The enzyme was activated by sulfhydryl compounds such as dithiothreitol and cysteine. The enzyme was strongly inactivated by TLCK, TPCK, antipain, leupeptin, and E-64. Consequently, we concluded that the enzymeis a cathepsin B-like enzyme because of its substrate specificities.

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Concentrations of four cations, protein content and osmolarity were measured on coelomic fluids and sera from 8 salmonid species. Sodium was the major cation inboth serum and coelomic fluid. The concentrations ranged 144-163mM in serum and 146-163mM in coelomic fluid and showed similar levels between serum and coelomic fluid in the same species. Meanwhile, potassium concentrations of both fluids varied in species (serum, 0.25-2.50mM; coelomic fluid 2.44-3.81mM), andtend tobe high in coelomic fluid. On the contrary, magnesium concentrations of coelomic fluid werelower than those of serum. Protein concentration of coelomic fluid wasabout 7-20% of that in serum in the individual species. Osmolality of coelomic fluid measured by the freezing point depression was only slightly but lower than the level of serum in all species. Immunoelectrophoretic test using antiserum against male serum proteins demonstrated that a part of coelomic fluid proteins originated from blood.

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The hemolymph of kuruma prawn Penaeus japonicus agglutinated horse, sheep, chicken, and human erythrocytes, but not a marine bacterium Vibrio anguillarum. The hemagglutinating activity was dependent on the presence of calcium ions. The higher titer values were obtained by keeping the reaction mixture at 6°C for 16 h compared to those observed at room temperature. The hemagglutinating activity was inhibited by glycoproteins and simple sugars such as mucin Type I, mucin Type II, fetuin, D-mannosamine, N-acetyl-D-glucosamine, and N-acetylneuraminic acid. The lectins were purified by affinity chromatography on mucin Type II-Sepharose 6 B. Succeeding separation by ion-exchange chromatography and gel-filtration revealed that the affinity purified lectins were a mixture of the lectins with different molecular species and also sugar-binding specificity. The two lectins were obtained in electrophoretically pure form; one (Fraction B-1) was a protein of 370 kDa consisted of subunits of 84 kDa and the other (Fraction D, 240 kDa) consisted with subunits of 34 kDa.

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A skin mucus extract of the loach Misgurnus anguillicaudatus agglutinated various types of mammalian erythrocytes including rabbit, sheep, human A, B, and AB. It did not react with horse or human 0 erythrocytes. The hemagglutinating activity of the mucus extract was lost when heatedand also at extreme pHs. The activitywas independent of the presence of calcium ion. Crossed absorptiontests revealedthat the skin mucus extract contained a single type of non-blood group specific lectins. Askin mucus lectin, named MAL-1, was isolated by ion-exchange column chromatography followed byrepeated gel-filtration on Sepharose S-200. The molecular weight of the intact MAL-1 was greater than300 kDa and consisted of heterogeneous subunits (40 and 41 kDa). MAL-1 was a glycoprotein and contained D-galactose(13.6%), D-mannose (2.1%), and L-xylose (2.5%). The absence of Cys residue in MAL-1 suggested that MAL-1 molecule held non-covalently. MAL-1 reacted with antibodies for the conger eel mucus lectin but not with those for acorn barnacle lectins. The lectin (MAL-2) having a smaller molecular weight was also present in themucus extract.

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Two experiments were conducted to find out if the occurrence of color abnormality and malformation in larval Japanese flounder could be prevented when enriching Artemia nauplii with vitamin A (VA) and its precursor. Ten-day-old larval flounder were chosen as the experimental fish and fed different strains of Artemia, Utahstrain in the first experiment and Tien-tsin strain in the second experiment.
Growth and VA content of larval flounder were almost the same in both experiments, except those fed Artemia enriched with 100×10³ IU VA in a 10 l medium which showed retarded growth and malformation. No abnormal coloration was observed in thefirst experiment. However, in the second experiment, color abnormality was recognized in all the groups, probably on feeding the Tien-tsin Artemia, and the percentage occurrence was effectively reduced by feeding the Artemia containing about 1, 000 IU VA. However, bone deformity of a higher degree, such as central fusion, abnormalbone formation in caudal fin, and abnormal formation of pterigiophores wasobserved in the fish fedthis level of VA.
These results suggest that VA seems to be effective in preventing the abnormal coloration caused by Tien-tsin Artemia, but the excess amount of this vitamin can exert ill effects on normal growth of flounder.

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This investigation was conducted to determine the total metal absorbed (μgg^-1 dry wt), removal (% day^-1), and accumulation rates of M. aeruginosa (Cyanophyceae), S. quadricauda (Chlorophyceae), and A. granulata (Bacillariophyceae) exposed to the different concentrations of copper, zinc, cadmium, and their combinations. Upon exposure to the different single and combination concentrations of heavy metals, the highest total metal absorbed, removal, and accumulation rates of thethree organisms were obtained for copper while their lowest values were obtainedfor cadmium. Total metal absorbed, removal, and accumulation rates were species specific. M. aeruginosa showed the highest values for all metals tested while S. quadricauda showed the lowest values. The accumulation rates of M. aeruginosa for a specific heavy metal were hardly affected by the presence of other metals inthe solution. However, in S. quadricauda and A. granulata, there were some remarkable reductions observed in their accumulation rates. This study provides information on the efficiency of the three freshwater microalgae to sequester heavy metals from an aqueous system as a possible pollution control and biomonitors or detectors of the biological impact of industries.

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Free D-amino acids were determined in the tissues of crustaceans, three macrurans and four brachyurans, using reversed-phase ion-pair HPLC after derivatization with (+)-1- (9-fluorenyl) ethyl chloroformate. Of several D-amino acids detected, D-alanine was the most abundant and widely distributed among every tissue of crustacean species determined. The content of D-alanine in the muscle of these crustaceans ranged from 3.2 to 16.8 μmol/g wet weight. The percentage of D-alanineto total alanine reached 31.7% on average.
The second predominant D-amino acid was D-arginine which was less than 2 μmol/g and accounted for less than 10% of the total arginine. Acidic amino acids, D-aspartate and D-glutamate, were presentonly in the tissues of macrurans and the contents were less than 1 μmol/g. The percentage of D-aspartate to total aspartate, however, varied from 12 to 70%. Several other D-amino acids were also detected in small quantities and low percentages.

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