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Volume 35, Issue 6
Displaying 1-18 of 18 articles from this issue
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Observations on Ovarian Eggs.Kikuo HIRAMOTO1969 Volume 35 Issue 6 Pages 517-523
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSIn order to observe the process of maturation and the number of eggs to be discharged during the spawning season, 175 specimens of female Japanese anchovy taken off BosoPeninsula during February through July 1966 and April through June 1967 were examined.
The maturity of Japanese anchovy could be classified by the diameter of large egg group and the number of modes in the distribution of diameter of eggs. The group of large eggs is called II-group.
The number of eggs in II-group estimated by gravimetric method was almost equal to the value estimated by volumetric method.
Frequency distribution of mean diameter of eggs has wider range at advanced stage than at earlier stage. The diameter of eggs in II-group increased with progress of maturation, although this was not referable to II'-group (medium-size egg group).
The diameter of eggs in II-group at spawning stage (D) was 1.05-1.60mm, which exce-eded the diameter of spawned eggs taken from the sea.
The number of eggs in II-group at Ba-C stage range from 600 to 20, 600 per individual female; mostly from 4, 000 to 17, 000.
The number of eggs (N) at ripening stage (C) was significantly correlated with body length of fish (L) at the coefficient of correlation, 0.774. The relationship between N and L can be expressed by the following formula: log N=0.155L+2.023
In the same stages (Bc-D), there was a trend that the heavier the ovaries weight the larger the number of eggs is.View full abstractDownload PDF (393K) -
Effect of Light Intensity and Population Density on the Growth Rate in Porphyra FrondsShigeru SHIMO, Shigeru NAKATANI1969 Volume 35 Issue 6 Pages 524-532
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThrough various experiments on artificial mass culture of Porphyra tenera, it was found that the growth rate relevant to light intensity and population density can be expressed as following equations.
The general equation of growth rate, expressed in complicated function of the factors; such as aging, population density, light intensity, and mutual shading, may be:
when f, g, and h are the functional notations of W (dry weight of a frond), C (number of fronds), and I (light intensity) respectively.
And, the mutual shading effect:
when Ic is light intensity of transmitted through the vessel, and I ?? is intensity of incident light, and B and α are constants.
Mean value of light intensity:
when L is width of the vessel.
Light intensity effect h(I) in the first equation
when b and a are constants.View full abstractDownload PDF (376K) -
Teiji KARIYA1969 Volume 35 Issue 6 Pages 533-536
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSIt has been suggested that the presence of a large caecum in active predaceous swimmers such as Scomber may be correlated with their capacity to attack shoals of fish and to consume large quantites of prey in a short time, In previous papers, the relationship of food intake to the weight of stomach contents was reported on Scomber. In this paper, the relationship above mentioned was examined on Mebaru (Sebastes inermis), which has the stomach of the same kind, but a different mode of life. Sebastes has a large ceacum, too. However, Sebastes is not an active swimmer unlike Scomber but rather a sluggish reef fish.
Food intake rate of Sebastes was smaller than that of Scomber. The maximum weight of the stomach contents in the state of satiety was 6.5-7.5%. The time required for the ingested food materials to be propelled out from the stomach into the intestine varied with water temperature, viz., 70 hours at 14°C, 120 hours at 10°C and 140 hours at 7°C. At a low temperature of 4.5°C, food intake rate was reduced to 1.4% of the body weiget. It was concluded that digestion speed in Sebastes was slower than that in Scomber.
In the state of the complete satiation the length and diameter of the stomach become the maximum; that is, the length of the longitudinal muscular layer of the stomach was 2.1-2.3 times as large as that of empty stomach, while the length of the circular muscular layer extended 2.5-3.0 times. This suggested that the Sebastes stomach is more elastic than the Scomber stomach.View full abstractDownload PDF (191K) -
Simultaneous Estimation of Parameters with the Transfer Effect of Pacific Yellowfin TunaTakeo ISHII1969 Volume 35 Issue 6 Pages 537-545
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESS1. The population parameters with transfer effect were estimated by tracing method for Pacific yellowfin tuna.
2. In stead of the recruitment ratio (γR), the ratio of the number of fish which recruits to Subarea W to the total, an index of the recruitment ratio (ζ=ln{γR/(1-γR)}) was suggested. The value of ζ was estimated simultaneously with other parameters by the tracing method.
3. In simultaneous five-factor-estimation, following results were obtained; ?? =0.0583, îr=1.767 (r1=r5=0.0040, r2=r4=0.1845 and r3=0.6228), ?? =0.4440, ζ=3.565 (γR=0.9725) and ?? =0.1385.
4. When age groups were stratified for T, it was found that the older ages had larger value of T than that of younger ages.
5. Five factors (M21, M22, T21, T22 and ζ) were estimated for various levels of q and Ir, and the values which make ξ value minimum were as follows; ?? =0.051, Îr=1.682, ?? 21=0.3421, ?? 22=0.9146, ?? =3.614 (γR=0.9737), ?? 21=0.1440 and ?? 22=0.5439 (r1=r5=0.0058, r2=r4=0.1943 and r3=0.5996).View full abstractDownload PDF (400K) -
Relation between Catch and Size of the GearNobuo HIRAYAMA1969 Volume 35 Issue 6 Pages 546-549
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThe catch in tuna longline fishing depends chiefly on the knowledge of the behaviour of tuna and the techniques of the gear handling. Biological factors, however, have hitherto often been neglected in the construction of the gear because of few data to be concerned with.
In the present paper, the fishing mechanism of tuna longline is studied from the relation between the behaviour of the fish and the size of the gear, such as hook intervals, mainline, branch line and float line in length. The data used here are of many longline fishing boats which carry various different sizes of gears, and operated in nearly the same fishing ground and at the same period.
The results obtained are as follows. When the catch (C) is assumed to be influenced by the factors that the school density (s) in a fishing ground, the soaking time (t) of the bait, hook intervals (d) and the radius (r) of an estimated spherical surface into which the bait is liable to attract the fish, the relation among them seems to be explained by the following equations:
C=st×d when d<r
C=st×2r when d>r
The depth at which hooks are suspended has practically no effect on the catch.View full abstractDownload PDF (238K) -
Relation between Setting Course of the Gear and Moving Direction of the FishNobuo HIRAYAMA1969 Volume 35 Issue 6 Pages 550-554
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSIn the operation of tuna longline, the fishing boats have usually set the lines in the direction as fishermen think fit without any available data. If the moving direction of tuna school is assumed in advance, very successful catches will be to obtained at the case when the longline is set so as to intersect the moving direction of the school at right angle.
The present paper treates the relation between the moving course of fish and the direct-ion of setting gears, based on the assumptions as follows:
(1) The catch (F) is proportional to number of fish (S) encountering the set of longline.
(2) The school is moving in a certain definite direction with a constant speed (v). From the above assumptions, S may be assessed as follows;
S=Nv| sinθ| ?? L (1) where N is the density of fish in the fishing ground, ?? the angle of the moving course of fish against the direction of setting gear, _??_; the mean soaking time of the gear and L the total length of the lnngline.
Furthermore, F is obtained from the following equation:
F=αNv/sinθ| ?? L (2) when α means individual catching rate of a gear.
From the equation (2) and the data of current direction, estimated moving directions of the schools are shown in Table 1, and consequently, it was found that the moving direction of tuna is related to the current, most of them move against a current, and thus the most effective setting of the gear is achieved at the direction normal to the current.View full abstractDownload PDF (241K) -
Gel Filtration of Sarcoplasmic and Myofibrillar Proteins on Sepharose 2BShigeru UMEMOTO, Koichi KANNA1969 Volume 35 Issue 6 Pages 555-558
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSIn the previous paper1) it was reported that several peaks of eluted proteins were observed in the elution diagrams of fish muscle protein by gel filtration on agarose gels. To interpret the elution profiles of fish muscle protein, gel filtrations on Sepharose 2B were carried out on sarcoplasmic protein, myosin and actomyosin prepared from fish muscle and also on myosin from rabbit muscle. In the obtained elution patterns, peaks of major compon-ent protein were observed at each definite elution volume (Figs. 1 and 2). Their Kav values were 0.9-1.0 for sarcoplasmic protein, 0.4-0.5 for myosin and 0.0-0.1 for actomyosin (Table 1). These results suggest that fish muscle protein can be fractionated into three kinds of proteins, sarcoplasmic protein, myosin and actomyosin (and/or aggregated protein) by gel filtration on Sepharose 2B.View full abstractDownload PDF (367K) -
Norio INOUE, Terushige MOTOHIRO1969 Volume 35 Issue 6 Pages 559-561
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSThe haemocyanins of Erimacrus isenbeckii, Paralithodes camtschaticus and Chionoecetes opilio were examined for starch gel electrophoretic patterns in order to contribute to their classification. There were detected 4, 3, and 5 components for E. isenbeckii, p. camtschaticus and C. opilio, respectively. There was no difference between both sexes of E, isenbeckii.View full abstractDownload PDF (124K) -
Ryo OKAMOTO1969 Volume 35 Issue 6 Pages 563-566
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSDownload PDF (323K) -
Reijiro HIRANO1969 Volume 35 Issue 6 Pages 567-569
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
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Teruo HARADA1969 Volume 35 Issue 6 Pages 570-573
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSDownload PDF (356K) -
Yutaka MURAKAMI1969 Volume 35 Issue 6 Pages 574-575
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSDownload PDF (108K) -
Tsutomu KITAZIMA1969 Volume 35 Issue 6 Pages 576-582
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSDownload PDF (456K) -
Shiro FUJITA1969 Volume 35 Issue 6 Pages 583-586
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
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Kiyoshi UCHIHASHI1969 Volume 35 Issue 6 Pages 587-591
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
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Tomowo HAYASHI1969 Volume 35 Issue 6 Pages 592-595
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
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Hiroshi TSUKAHARA1969 Volume 35 Issue 6 Pages 596-598
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
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Minoru YANO1969 Volume 35 Issue 6 Pages 599-601
Published: June 25, 1969
Released on J-STAGE: February 29, 2008
JOURNAL FREE ACCESSDownload PDF (181K)
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