298
MAKO‘I‘O OMOR1
Ix. (_’tTBMI(’AIA C:OnfPOSITION
Prclimiiiary hiorlicmionl iuittlysce of some pelagic shrimps in the
Izu rcgioii Iisvc besn c*arricd out, to chtrrminc the contents of total
c*arboii, nitrogen, h y d r o p i allti i t ~ l i . All scimples bltt Acetes j f t p ~ n i c ~
wcre obtteincd in tht- it\lt11)>31> : thcy w c w f~ee.r,e-dried at -GoC and
wc4ghrd. Inmcdiatcly prior to the biocheriiical malyses, each sample
~oritairiing t i t least three, but rnostJlv eight to ten, individuals was
thoroughly ground. The sndyses were carried out by the same method
ILR dcwribetl previously for several zooplankton species (Omori, 1969b).
To detcrniiw thr amount of total protein, the value of nitrogen
obtniiicd wits tnultiplird by i t factor 6 - 2 5 The result is shown in Table
V1I. Total cwt)on (*ontent varied from 40.20(, to 64.3% of the dry
weight. Tht. nvwage valur obtuinccl for spccies was 47.3%. Three
bitttiyp(~lu#io specictl, i.c. Brntheopnmemn borealis, J’arapasiphae
sulcntifron,s i ~ n d I’hys~tocaris microphthalmu, showcd apparently
highrr rnrlon wntent thttn the other shrimps. Total nitrogen content
ranged betwecii 5.?y0 iind I1.5%, with un average of 9.5%. A clear
rliffereiicr: 11 ;is forintl in the protein content of the shrimps occuring in
epipclirgic a n d upper rneuopchgic zoncs lts compared to those of the
btithypelagio zone. ‘ I2 hc average protein contciit of six species including
juveniles of the deeper forms which inhabit the upper 400 r n was 67*5y0,
whereas that of three bi~thypebgic species was 39.3%. There was
il tmdency for clccp-living forms to hitve a higher C/N ratio. The
water coiitont of pclitgic shrimps ruiiged from 75 to 85% approxirnutely i d iwh contcnt reprcscntcd from 4.4% of the dry weight for
ocwinic. sproios BvntheogunnPma borwlis to 1.?.5%, for neritic form
.4cetm jczponicu.?.
Little i~if~r~nittion exists on t h c b biodiernical composition of pelagic
sliritiips. Jtityniont et ul. ( 1!W7. l!%Ij) hitvc analyseci thc fraction8 of
protein, lipid, cwboliydratcb uiid L L R ~ of Cennadas propinpus (as
0. rluuicnrpus), rl cnniheph!/ra yurpurpu and wpecien of the genera
Ir’uticlrtrlin. Scrpstes. A wnthrphyur arid S!/s!ellaspis. Their data suggefit
53-64?, protein, 1 - 3 Y o carbohydrate ltnd 15-24% ash in dry weight
of the shrimps. Although their m h valiics arc’ relatively higher than the
present one, the iippcr range is siiniliir.
Table VIIl shows lipid contrnt of sonic pelagic shrimps that have
so fiir beeii iLiialyscd. Apiirt from Hiwfheoqmncma borealis, Petalidium
foliacpu)ti, StjrgeutPs sirnilis, h y i a hisu1catu.v (N’ood-Miison) and
S . h c e n s which were obtaiard in tlic North Pacific, all sarnplw were
taken i i i tho North AtliLntiv ( h t ~ n . I n most cases, thc lipid contents
were ex-presscd as percxwtugr. of wet w i g h t . They wtm nonvrrted to
MAKO‘I‘O OMOR1
Ix. (_’tTBMI(’AIA C:OnfPOSITION
Prclimiiiary hiorlicmionl iuittlysce of some pelagic shrimps in the
Izu rcgioii Iisvc besn c*arricd out, to chtrrminc the contents of total
c*arboii, nitrogen, h y d r o p i allti i t ~ l i . All scimples bltt Acetes j f t p ~ n i c ~
wcre obtteincd in tht- it\lt11)>31> : thcy w c w f~ee.r,e-dried at -GoC and
wc4ghrd. Inmcdiatcly prior to the biocheriiical malyses, each sample
~oritairiing t i t least three, but rnostJlv eight to ten, individuals was
thoroughly ground. The sndyses were carried out by the same method
ILR dcwribetl previously for several zooplankton species (Omori, 1969b).
To detcrniiw thr amount of total protein, the value of nitrogen
obtniiicd wits tnultiplird by i t factor 6 - 2 5 The result is shown in Table
V1I. Total cwt)on (*ontent varied from 40.20(, to 64.3% of the dry
weight. Tht. nvwage valur obtuinccl for spccies was 47.3%. Three
bitttiyp(~lu#io specictl, i.c. Brntheopnmemn borealis, J’arapasiphae
sulcntifron,s i ~ n d I’hys~tocaris microphthalmu, showcd apparently
highrr rnrlon wntent thttn the other shrimps. Total nitrogen content
ranged betwecii 5.?y0 iind I1.5%, with un average of 9.5%. A clear
rliffereiicr: 11 ;is forintl in the protein content of the shrimps occuring in
epipclirgic a n d upper rneuopchgic zoncs lts compared to those of the
btithypelagio zone. ‘ I2 hc average protein contciit of six species including
juveniles of the deeper forms which inhabit the upper 400 r n was 67*5y0,
whereas that of three bi~thypebgic species was 39.3%. There was
il tmdency for clccp-living forms to hitve a higher C/N ratio. The
water coiitont of pclitgic shrimps ruiiged from 75 to 85% approxirnutely i d iwh contcnt reprcscntcd from 4.4% of the dry weight for
ocwinic. sproios BvntheogunnPma borwlis to 1.?.5%, for neritic form
.4cetm jczponicu.?.
Little i~if~r~nittion exists on t h c b biodiernical composition of pelagic
sliritiips. Jtityniont et ul. ( 1!W7. l!%Ij) hitvc analyseci thc fraction8 of
protein, lipid, cwboliydratcb uiid L L R ~ of Cennadas propinpus (as
0. rluuicnrpus), rl cnniheph!/ra yurpurpu and wpecien of the genera
Ir’uticlrtrlin. Scrpstes. A wnthrphyur arid S!/s!ellaspis. Their data suggefit
53-64?, protein, 1 - 3 Y o carbohydrate ltnd 15-24% ash in dry weight
of the shrimps. Although their m h valiics arc’ relatively higher than the
present one, the iippcr range is siiniliir.
Table VIIl shows lipid contrnt of sonic pelagic shrimps that have
so fiir beeii iLiialyscd. Apiirt from Hiwfheoqmncma borealis, Petalidium
foliacpu)ti, StjrgeutPs sirnilis, h y i a hisu1catu.v (N’ood-Miison) and
S . h c e n s which were obtaiard in tlic North Pacific, all sarnplw were
taken i i i tho North AtliLntiv ( h t ~ n . I n most cases, thc lipid contents
were ex-presscd as percxwtugr. of wet w i g h t . They wtm nonvrrted to