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1.
For a period of 1 year, some blood parameters were evaluated on a monthly basis in a population of adult European sea bass (Dicentrarchus labrax L.) intensively reared in floating marine cages (Ionian Sea, Mediterranean). From April (13 months old) to July (16 months old) males (35–50%) and sexually indeterminate individuals were collected. From August to March (24 months old) only males were sampled. During this period the percentage of spermiated males was highest (100%) from November (20 months old) to January (22 months old). Plasma testosterone in males was inversely related to sunlight (h month?1) and was elevated between October and January, when males first achieved sexual maturity. Testosterone showed the highest value (0.49 ± 0.02 ng ml?1) in January and the lowest (0.09 ± 0.02 ng ml?1) in March. Haematocrit, red blood cell counts and haemoglobin concentration were elevated from November to March, being inversely related to sunlight. The two latter parameters were also inversely related to daily food intake. Haematocrit, red blood cell counts and haemoglobin concentration were highest in December [53 ± 1%, (5.36 ± 0.06) × 106 mm?3, 10.08 ± 0.14 g 100 ml?1, respectively] and lowest in June [35 ± 1%, (3.33 ± 0.05) × 106 mm?3, 6.47 ± 0.13 g 100 ml?1, respectively]. White blood cell counts were not correlated with sea water temperature, sunlight or daily food intake. They were highest in February [(8.45 ± 0.20) × 104 mm?3] and lowest in April [(6.07 ± 0.14) × 104 mm?3]. Total plasma protein concentration (4.88 ± 0.11–5.93 ± 0.10 g 100 ml?1) and mean cell volume (93.3 ± 0.9–105.5 ± 1.8 μm3) showed small fluctuations throughout the year. Sexual maturity appears to be a major factor that significantly affects haemopoiesis of D. labrax. This study contributes to the evaluation of normal levels of some blood parameters in European sea bass, which are helpful for the assessment of physiological status and health of this species.  相似文献   

2.
3.
The study purpose was the analysis of barbel Barbus barbus (L.) milt quality and quantity with regard to the time following stimulation with [(D‐Ala6, Pro9NEt)‐mGnRH+metoclopramide] i.e. Ovopel. Selected parameters such as total volume of milt (TVM, ml), volume of milt per kg of body weight (VOM, ml kg?1 b.w.), sperm concentration (×109 ml?1), total sperm production (TSP, ×109), osmolality (mOsm kg?1) and pH of seminal plasma were determined. Sperm motility was analyzed by the CASA system, i.e. the percentage of sperm motility (MOT, %) and their progressive motility (PRG, %), curvilinear velocity (VCL, μm s?1) and straight line velocity (VSL, μm s?1), amplitude of lateral head displacement (ALH, μm), and beat cross frequency (BCF, Hz). Milt was collected from 12 specimens (N = 12), with the first portion obtained 12 h following treatment with Ovopel (1 granule kg?1 b. w.). Subsequent portions of milt were taken at 24 h intervals, i.e. after 36, 60, 84, 108, and 132 h. The control group (Control, N = 12) was injected with 0.9% NaCl at 0.5 ml kg?1b.w. from which milt was taken 12 h post injection. The highest TVM, VOM and TSP values were recorded 12 h after Ovopel treatment (3.2 ± 0.7 ml, 36.7 ± 10.5 ml kg?1 b.w. and 39.1 ± 9.4 × 109, respectively); lowest values were recorded after 132 h (0.8 ± 0.4 ml, 11.1 ± 6.5 ml kg?1b.w. and 13.7 ± 7.5 × 109, respectively). The highest seminal plasma osmolality values (300.0 ± 42.6 mOsm kg?1) as well as the lowest sperm concentration (12.5 ± 1.5 × 109 ml?1) were observed 12 h after Ovopel treatment. No significant differences in the percentage of sperm motility (MOT) were noted during any of the periods after hormonal stimulation, however, a change in the character of their movement (PRG) was observed. The lack of significant differences (P > 0.05) in VCL and VSL values between 12 h and 60–132 h indicates that the lengthening of time does not lead to a decrease in sperm velocity and, therefore, is not likely to have a negative impact on their quality. The highest ALH (1.9 ± 0.2 μm) and BCF (11.5 ± 1.1 Hz) values were observed when the effect of stimulation was most noticeable, i.e. 12 h after Ovopel treatment. Based on the total milt volume and sperm production, the best time for milt collection from barbel is 12 h post‐hormonal treatment; 84 h post‐hormonal treatment, TVM, VOM, TSP and some CASA parameters decreased, which suggest the same aging process in sperm.  相似文献   

4.
In the present investigation a chromate tolerant rhizobacterium Kocuria flava was isolated and inoculated to the Cicer arietinum L to evaluate its effects on growth and chromium accumulation upon exposure of different concentration of chromium (1–10 μg ml?1) as Cr (VI) for 24 d. K. flava inoculated plant of C. arietinum demonstrated luxuriant growth as compared to non inoculated plant at respective concentration of Cr (VI). K. flava found to ameliorate chromium induced phytotoxicity in terms of chlorophylls, carotenoid and protein contents and thus helps the plant in acquiring higher biomass with high chromium concentration. After 24 d, maximum concentration of chromium recorded in root of C. arietinum (4892.39 μg g?1dw) inoculated with K. flava as compared to non inoculated plant (1762.22 μg g?1dw) upon exposure of 5 μg ml?1Cr (VI). Therefore, application of C. arietinum in association with K. flava could be more efficient in decontamination of chromium polluted site. Moreover, K. flava may be used as a bioresource for developing microbes assisted phytoremediation system due to its compatibility.  相似文献   

5.
Abstract

The emergent need for new treatment methods for multi-drug resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) has focused attention on novel potential tools like nanoparticles (NPs). In the present study, a drug-free cationic nanoparticles (CNPs) system was developed and its anti-MRSA effects were firstly investigated. The results showed that CNPs (261.7?nm, 26.1?mv) showed time- and concentration-dependent activity against MRSA growth, killing ~ 90% of planktonic bacterial cells in 3?h at 400?μg ml?1, and completely inhibiting biofilm formation at 1000?μg ml?1. Moreover, CNPs at 400?μg ml?1 reduced the minimum inhibitory concentration (MIC) of vancomycin on inhibition of planktonic MRSA growth (~ 25%) and biofilm formation (~ 50%). The CNPs–bacteria interaction force was up to 22 nN. Overall, these data suggest that CNPs have a good potential in clinical applications for the prevention and treatment of MRSA infection.  相似文献   

6.
A recent sample (28 specimens from South Georgia and 1 from Shag Rocks) of the plunderfish Artedidraco mirus collected in June 2004 during the ICEFISH Cruise yielded sufficient data to refute two long-held assumptions about this species: (1) it is endemic to South Georgia; (2) its mental barbel is sexually dimorphic (tapered in females and club-shaped with papillae in males). A. mirus exhibits three types of mental barbel: A: tapered without a terminal expansion; B: with a narrow terminal expansion composed of simple papillae; C: with a wide terminal expansion composed of convoluted or elaborately branched papillae. There is no correlation between barbel type and body size or sex. We also found sexual dimorphism in the relative height of the second dorsal fin (30% higher on average in males) and in the colour of the anal fin (black in males over 60 mm SL). The largest males possess a prominent ruffled urogenital papilla, also black in colour. Barbel histology resembles that of other artedidraconids (Dolloidraco longedorsalis, Pogonophryne scotti) studied in containing large nerve trunks and blood vessels lateral to a pseudocartilaginous core and dermal papillae with an extensive network of nerves and blood vessels. The high degree of intraspecific variation in artedidraconid barbel structure warrants caution in using this structure as a diagnostic taxonomic character.  相似文献   

7.
Aims: To determine if the purported deaminase inhibitors diphenyliodonium chloride (DIC) and thymol reduce the growth and survivability of Campylobacter. Methods and Results: Growth rates of Campylobacter jejuni and Camp. coli were reduced compared to unsupplemented controls during culture in Muellar–Hinton broth supplemented with 0·25 μmol DIC or thymol ml?1 but not with 0·01 μmol monensin ml?1 or 1% ethanol. Recovery of Camp. jejuni and Camp. coli was reduced >5 log10 CFU from controls after 24 h pure culture in Bolton broth supplemented with 0·25 or 1·0 μmol DIC ml?1 or with 1·0 μmol thymol ml?1. Similarly, each test Campylobacter strain was reduced >3 log10 CFU from controls after 24 h mixed culture with porcine faecal microbes in Bolton broth supplemented with 0·25 or 1·0 μmol DIC ml?1 or with 1·0 μmol thymol ml?1. Treatments with 0·25 μmol thymol ml?1, 0·01 μmol monensin ml?1 or 1% ethanol were less effective. Ammonia production during culture or incubation of cell lysates was reduced by 0·25 or 1·0 μmol DIC ml?1 but only intermittently reduced, if at all, by the other treatments. Conclusions: Diphenyliodonium chloride and thymol reduced growth, survivability and ammonia production of Camp. jejuni and Camp. coli. Significance and Impact of the Study: Results suggest a potential physiological characteristic that may be exploited to develop interventions.  相似文献   

8.
To study growth rates, movements and estimate population size of shortfin eels Anguilla australis in a small lake (2·5 ha) near Christchurch, New Zealand, 617 A. australis were tagged with PIT tags. Tag retention was high (95%) and over the seven recapture events spread over 2 years, 55% of tagged A. australis were recaptured. Growth of recaptured A. australis averaged 13·1 mm year?1 and declined slightly with increasing total length. Distance moved from original capture site increased with increasing time at large. Population estimates of A. australis > 400 mm (susceptible to capture by fyke net) from recaptures of individuals averaged 1451 A. australis, with a biomass of 170 kg ha?1. An average of 6·6% of the estimated total population matured as male silver A. australis each year. Results from radio‐tracking of four A. australis gave an average nightly foraging area of 2780 m2, and there was no apparent preference for inshore movement (within 5–6 m of the shoreline) or offshore movement. Fyke‐net efficiency (total catch relative to the estimated total population available to each net) measured over four consecutive nights fishing was 88%. The lack of precision of the shoreline triangulation system used, ±10 m, meant that the positional data were considered too coarse to be used in a proposed novel population estimation technique based on determining population size within foraging areas.  相似文献   

9.
Abstract

P22 phage >105 PFU ml?1 could be used to inhibit Salmonella Typhimurium biofilm formation by 55–80%. Concentrations of EDTA >1.25?mM and concentrations of nisin >1,200?µg ml?1 were also highly effective in reducing S. Typhimurium biofilm formation (≥96% and ≥95% reductions were observed, respectively). A synergistic effect was observed when EDTA and nisin were combined whereas P22 phage in combination with nisin had no synergistic impact on biofilm formation. Triple combination of P22 phage, EDTA and nisin could be also used to inhibit biofilm formation (≥93.2%) at a low phage titer (102 PFU ml?1), and low EDTA (1.25?mM) and nisin (9.375?µg ml?1) concentrations. A reduction of 70% in the mature biofilm was possible when 107 PFU ml?1 of P22 phage, 20?mM of EDTA and 150?μg ml?1 of nisin were used in combination. This study revealed that it could be possible to reduce biofilm formation by S. Typhimurium by the use of P22 phage, EDTA and nisin, either alone or in combination. Although, removal of the mature biofilm was more difficult, the triple combination could be successfully used for mature biofilm of S. Typhimurium.  相似文献   

10.
A pharmacokinetic study of oxytetracycline (OTC) following a single (100 mg kg?1) or a multi‐dose (100 mg kg?1 for 5 days) oral administration was carried out in yellow catfish, Pelteobagrus fulvidraco. After oral administration at 25°C, a one‐compartment model was developed. The absorption half‐life (t1/2(ka)) was 3.92, 1.44, 2.75, and 3.34 h in plasma, muscle, liver, and kidney after the single dose, and 0.35, 0.22, 0.42, 0.32 h after the multi‐dose, respectively. The order of peak concentration (Cmax) was liver > kidney > plasma > muscle, at 3.48 μg g?1, 2.90 μg g?1, 1.46 μg ml?1, and 1.39 μg g?1 after the single dose, and 14.02 μg g?1, 8.51 μg g?1, 4.17 μg ml?1, and 3.84 μg g?1 after the multi‐dose, respectively. The elimination half‐lives (t1/2(ke)) of OTC in plasma, muscle, liver, and kidney were calculated to be 7.64, 26.29, 19.08, and 10.61 h after the single dose, and 47.54, 70.99, 49.87, and 47.73 h after the multi‐dose, respectively. The results suggest that OTC was absorbed faster after the multi‐dose than after the single dose, suggesting that OTC could be more efficacious after the multi‐dose and more effective in the control bacterial diseases in aquaculture, with the side effects of longer withdrawal periods.  相似文献   

11.
Administration of flumequine and oxolinic acid to turbot, Scophthalmus maximus L., by bath resulted in significant levels of both drugs in the muscle tissue. Bath treatment using 150 mg L?1 of flumequine and 200 mg L?1 of oxolinic acid for 72 h gave muscle concentrations of 10.2 and 6.2 μg g?1, respectively. Excretion of both antibacterials was rapid, reaching concentrations of 0.8 and 0.9 μg g?1, respectively, for flumequine and oxolinic acid 24 h after the end of treatment. At day 3 post‐treatment the concentration of flumequine was below the limit of quantitation (0.1 μg g?1) of the analytical method. Based on a minimum inhibitory concentration (MIC) of 0.0625 μg ml?1 for susceptible strains, bath treatment maintain muscle levels in excess of 0.5 μg ml?1, corresponding to eight times the MIC‐value for approximately 118 h for oxolinic acid and 104 h for flumequine.  相似文献   

12.
Anti-fungal activities of two essential oils (peppermint oil and eucalyptus oil) and their main components (menthol and eucalyptol, respectively) against molds (Aspergillus niger, Penicillium chrysogenum, and Penicillium sp.) and a white-rot decay fungus (Trametes versicolor) identified from rubberwood surfaces were investigated. The broth dilution method and the agar diffusion technique were employed to determine the minimal inhibitory concentration (MIC) and the minimal fungicidal concentration (MFC) using the concentration of substances between 100 and 800 μl ml?1. Inhibitory effects of essential oils and their main components at the MICs against mold growth, fungal decay, and termite attack on rubberwood were further examined by means of the dip treatment method. It was found that MFC values against molds for all treatments examined were about 50–100 μl ml?1 higher than MIC values. Peppermint oil and menthol exhibited high fungistatic and fungicidal activities, with MICs of 300 μl ml?1 and 350 μl ml?1, respectively, against the test molds and the decay fungus. Eucalyptus oil and eucalyptol were also effective against these microbes but at higher concentrations of 600 μl ml?1 and 500 μl ml?1, respectively. Only peppermint oil at the MIC was capable of providing a complete protection from mold growth on rubberwood for up to 12 weeks at storage conditions of 25 °C and 100% RH. Both peppermint oil and eucalyptus oil at the MICs showed moderate resistance to fungal decay and high resistance to termite attack.  相似文献   

13.
The sensitivity of Alternaria solani isolates to the fungicides mancozeb and chlorothalonil was evaluated, to determine if inadequate disease management by these fungicides could be attributed to reduced sensitivity of A. solani isolates to these fungicides. The sensitivity of 60 isolates of A. solani was assessed using the inhibition of radial mycelial growth (RG) method, using fungicide concentrations of 0, 1.0, 10, 100, 500 and 1000 μg a.i ml?1 medium. EC50 was calculated for each isolate and fungicide combination. The EC50 values of different A. solani isolates to mancozeb ranged from 9.05 to 712.65 μg ml?1. EC50 values of different isolates to chlorothalonil ranged from 4.25 to 849.4 μg ml?1. The percentage of isolates with reduced sensitivity was 46.7 and 53.3% for mancozeb and chlorothalonil, respectively. Results of the in vivo tests demonstrated decline in disease control by the two fungicides with the reduced-sensitivity isolates compared to the sensitive ones.  相似文献   

14.
The hemolymph of last instar Manduca sexta larvae contains a protein factor that enhances ecdysone synthesis by prothoracic glands in vitro. The titer of the factor fluctuates during development in a pattern that suggests that it is regulated by juvenile hormone (JH). In untreated control larvae, the titer drops from 2.17 U ml?1 on day 1 to 0.27 U ml?1 on day 3. When larvae were treated with (7S)-hydroprene (a JH analog), the titer remained elevated (2.09 U ml?1 on day 3). JH I, however, was ineffective in preventing the precommitment drop in the titer of the factor. After pupal commitment, the titer of the factor increases in untreated larvae from 0.84 U ml?1 on day 5 to 1.62 U ml?1 on day 7. This increase was blocked when the sources of JH (the corpora allata) were removed on day 5 by head ligation. When head-ligated day 5 larvae were treated with either (7S)-hydroprene or JH I, the titer of the factor was driven to a level (1.88 U ml?1 and 2.05 U ml?1, respectively) that was not significantly different from that found in untreated day 7 larvae (1.62 U ml?1). The combined results indicate the titer of the hemolymph factor is regulated by JH.  相似文献   

15.
The maturation and growth pattern of the fluvial eight-barbel loach Lefua sp. (Japanese name: nagare-hotoke-dojo), an endangered species, was investigated using an individual identification-recapture method from 1995 to 1998 in an upper reach of a headwater tributary of the Kako River, Hyogo Prefecture, Japan. Based on observations of the gonads through the abdominal skin, the loach was estimated to breed mostly from May to July. All the males matured by age 1+, and all the females matured by age 2+. Gamete release in all individuals of both males and females was predicted from recaptured loaches during each breeding season. The standard length of mature females was significantly larger than that of males, showing sexual size dimorphism (SSD). The maximum sizes recorded were 75.4 mm SL for females and 61.2 mm SL for males. Both males and females of immature specimens grew mainly from May to November, including the breeding season, with no significant differences in growth rates between them. After sexual maturity, both males and females grew mainly from July to October (or November), after the breeding season, and the females exhibited higher growth rates than males. Therefore, SSD of the species seems to be attributable to the different growth rates after maturity. The longevity of the loach was estimated to exceed ten years based on individual growth patterns of various sizes during the survey period. It is likely that the loach has an iteroparous life history, breeding every year, and moderate growth rates after maturity.  相似文献   

16.
Plant essential oils are potential sources of insecticidal compounds, but have rarely been explored for their effect on termites. In the present study, we assessed the chemical composition of essential oils of Lippia sidoides Cham. (pepper‐rosmarin; Verbenaceae) and Pogostemon cablin (Blanco) Benth. (patchouli; Lamiacaeae) and evaluated their toxicity, behavioral impairment, and repellence to termite species of the genera Amitermes and Microcerotermes (Isoptera: Termitidae: Termitinae). The main components of essential oils of L. sidoides and P. cablin were thymol (44.6%) and patchouli alcohol (36.6%), respectively. The essential oil of P. cablin was most potent against Amitermes cf. amifer Silvestri and had the lowest LD50 (0.63 μg mg?1). There was no difference in toxicity for Microcerotermes indistinctus Mathews between the essential oils of L. sidoides (LD50 = 1.49 μg mg?1) and P. cablin (LD50 = 1.67 μg mg?1). Pogostemon cablin essential oil was the most toxic to M. indistinctus (LC50 = 0.32 μl ml?1) and A. cf. amifer (LC50 = 0.29 μl ml?1). The essential oils analyzed exhibited high toxicity and repellence to the termites, in addition to reducing behavioral interactions among individuals, thus constituting potential termiticides.  相似文献   

17.
This study investigated the antimicrobial effects of the ethanolic extract of Brazilian red propolis (BRP) on multispecies biofilms. A seven-day-old subgingival biofilm with 32 species was grown in a Calgary device. Biofilms were treated with BRP (1,600, 800, 400 and 200?μg ml?1) twice a day for 1?min, starting from day 3. Chlorhexidine (0.12%) and dilution-vehicle were used as positive and negative controls, respectively. On day 7, metabolic activity and the microbial composition of the biofilms by DNA-DNA hybridization were determined. The viability data were analyzed by one-way ANOVA followed by Tukey’s post hoc, whereas the microbial composition data were transformed via BOX-COX and analyzed using Dunnett’s post hoc. BRP (1,600?μg ml?1) decreased biofilm metabolic activity by 45%, with no significant difference from chlorhexidine-treated samples. BRP (1,600?μg ml?1) and chlorhexidine significantly reduced levels of 14 bacterial species compared to the vehicle control. Taken together, BRP showed promising antimicrobial properties which may be useful in periodontal disease control.  相似文献   

18.
This study evaluated the effect of the protease inhibitor ritonavir (RIT) on Trichosporon asahii and Trichosporon inkin. Susceptibility to RIT was assessed by the broth microdilution assay and the effect of RIT on protease activity was evaluated using azoalbumin as substrate. RIT was tested for its anti-biofilm properties and RIT-treated biofilms were assessed regarding protease activity, ultrastructure and matrix composition. In addition, antifungal susceptibility, surface hydrophobicity and biofilm formation were evaluated after pre-incubation of planktonic cells with RIT for 15 days. RIT (200 μg ml?1) inhibited Trichosporon growth. RIT (100 μg ml?1) also reduced protease activity of planktonic and biofilm cells, decreased cell adhesion and biofilm formation, and altered the structure of the biofilm and the protein composition of the biofilm matrix. Pre-incubation with RIT (100 μg ml?1) increased the susceptibility to amphotericin B, and reduced surface hydrophobicity and cell adhesion. These results highlight the importance of proteases as promising therapeutic targets and reinforce the antifungal potential of protease inhibitors.  相似文献   

19.
Aims: We report the analysis of genetic determinants conferring resistance to pristinamycin in Staphylococcus epidermidis strains and epidemiology typing of these strains by pulsed‐field gel electrophoresis. Methods and Results: Staphylococcus epidermidis (346 isolates) were searched for strains with pristinamycin resistance. Pristinamycin‐resistant strains (seven isolates) were isolated in five patients with haematological cancer in the Bone Marrow Transplant Centre of Tunisia in 2002. Resistance to pristinamycin was observed in 2% of isolates. The seven pristinamycin‐resistant strains shared resistance to oxacillin (MIC = 8–512 μg ml?1), gentamicin (MIC = 16–512 μg ml?1), erythromycin (MIC > 1024 μg ml?1), lincomycin (MIC > 1024 μg ml?1), pristinamycin (MIC = 4–16 μg ml?1) and rifampin (MIC = 128–256 μg ml?1). erm genes were amplified: ermA from six strains and ermC from one. vga gene encoding streptogramins A resistance (pristinamycin résistance) was amplified from all strains and typed as vgaA by analysis after electrophoresis of restriction profiles of vga amplicons (two fragments with Sau3A of 164 and 378 bp; one fragment with EcoRI). Pulsed‐field gel electrophoresis (PFGE) of SmaI chromosomal DNA digests of the seven S. epidermidis isolates divided them into two distinct pattern types: pulsed‐field type A (classified from A1 to A6 subtypes) and type B. The six strains harbouring ermA genes belonged to the PFGE type A while the strain harbouring ermC genes belonged to the PFGE type B. We characterized an epidemic strain carrying the vgaA and ermA genes responsible for the outbreak. Conclusions: Two clones of pristinamycin‐resistant S. epidermidis were isolated in our patients. One of them, isolated in all patients, had expanded over six months suggesting acquisition by cross‐contamination. Significance and Impact of the study: Increasing isolation of pristinamycin resistant S. epidermidis strains is an alarming indicator of nosocomial dissemination. The vector will be determined to establish a system of epidemiological surveillance.  相似文献   

20.
In 1998, 9500 juvenile New Zealand longfin eels Anguilla dieffenbachii (mean total length, LT, 42 cm) captured from the lower Clutha River were transferred upstream to Lake Hawea, a high‐country oligotrophic lake in the same catchment where recruitment of juvenile eels has been prevented by hydroelectric dams since 1958. A total of 2010 of the transferred A. dieffenbachii were tagged with coded wire tags. Ten years later in 2008, the A. dieffenbachii population in Lake Hawea was sampled resulting in 399 recaptures (distinguishable by the presence of tags and by LT from the remnant resident population of large old A. dieffenbachii) of the 1998 transfers; 79 (19·2%) of the recaptured fish had tags compared with 21·3% at release, indicating good tag retention and low mortality due to tagging. All recaptured tagged A. dieffenbachii were female. Mean annual growth over the 10 years since release was 3·80 cm year?1 for all recaptures and 3·65 cm year?1 for tag recaptures, and both were significantly greater than the estimate of 2·38 cm year?1 at release. After release, mean condition (K) increased significantly (P < 0·001) for all recaptures and tag recaptures. Annual length growth increment was linear. Tag recaptures showed significant increases in somatic growth rate post‐transfer, and otoliths from the 2008 recaptured A. dieffenbachii were examined to see whether any similar enhanced growth after transfer was incorporated into the otolith structure that would serve as a date stamp. Measurement of otolith ring radii indicated that an increase in the radius occurred on most otoliths corresponding to the year after transfer. Because there was 9 years of completed growth following the observed growth inflection on the otoliths, this was strong evidence that opaque rings were formed annually.  相似文献   

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