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1~AY-14-9
<br />•~~~a
<br />1t.~6
<br />S54
<br />CsIISAT Basuv Narva,-t.rtrr
<br />', furrhet explanation. 13y the time of hatc~iag,
<br />bwh sib of embryos wore of comparabW
<br />ie~th•
<br />rievelopttrg embryos were maintained in
<br />an indoor raceway at willow Beach For ~•
<br />hours at temperatmus ringing From 13 to 17
<br />C. Eggs were that traacporled oo aquaria at
<br />Arizona State University, wleee+e develo eat
<br />coniiaued at a caaestant tcmperat~e of 2.0 C.
<br />Obscrvatians and rocasurements were re'_
<br />cordoe'1 from living specimens by a srareo-
<br />micrnsonpe equipped with ocular snicramo-
<br />t~sr snd camera lucida, arbd with a range of
<br />etace~~ification of 2 to 2,000 X. AIl mcasY,ro-
<br />etuCUls arc of total length.
<br />Obscrvatians on the 1075 cohort were
<br />made hourly throw fire firs 3{i hams, then
<br />every 2 hours ~ ' niter hs-tching. Illustra-
<br />tions of selected sues tbrongh proluval de-
<br />velopnusit were prepared dirougb use of a
<br />camera hrcida and From photographs Oveua
<br />,~ through prolarvnl c~velopment prase:anted
<br />here is thus based ~ flee 111'5 fish. 5peci-
<br />:rrerrs were preserved perfodiC~.Qy in 8.ceta-
<br />~ fartaalic acid (AFA; 9.t1 parts ethanol, 0.4
<br />parts 4Q pen:ent formaldehyde, sad t1.5 parts
<br />glacial acetic ~id)w 3iVb~ea larvae began t4
<br />swim snd fc~d actively, samples were pro-
<br />servu] lass frequently.
<br />•' 1]evelopment of the raaorbaclc ~tc4ser was
<br />~ diritled into fiver major phases as defined by
<br />• Aubl~ {1943x: (1) embryological devel-
<br />optneat; fertilisnct3on of rho egg unlll hatc:h-
<br />ing; (Q) prolarval develapunent, lrAtching to
<br />a.bsorptiQn of yolk; (3) pastlarval devel-
<br />opncent, yolk absorption to esaification of
<br />pelvic fin-rays; and, (4) juventle dcvel-
<br />opsncnt, pcIvic ray assiCcation to maturation
<br />of gonads. DevoZopmncat slagitt~ followed Ba-
<br />Iitssky's (19lB) general pattern for cyprinid
<br />fishes. DesL~lpdve ternilrROlo wss derived
<br />from flydor {1$8.5}, Stewart 9,26), Tavolga
<br />(1949), Witut and Miller (1953), and Long
<br />and lkellaid {1978). ,
<br />. ~SUL1$
<br />~sllnyological Deveh~pmetet
<br />t Stage L• ®fc~rtil~d egg; day 0, 0 hour, I.5
<br />! mm diameter. Ova milky white aced
<br />• translucent.
<br />ISHERY & WILQLIFE 81U FAX 1~0. 904915091
<br />P, 0
<br />VaI.4E, No. 4
<br />Stage ~: fertflazesd egg; say I, I hour, 1.8
<br />rnen ctiamatstr. CLorirnn transixtreut seal yolk
<br />milky-white eeeid tresearlueeret; arlle,ial pole leaf
<br />yet visible to unaided cyet. Wat4r-hart]~~.r3
<br />eggs with greater speoifir: gravity ilcare water,
<br />ova demersal, chorian adln-live. ova atHtcri,ig
<br />to substrate and ono anotlusr. /~+
<br />.Sti~C 3: pi b1~5tt1mCr~'f, 3 llblli'S \r 'g' 1~,
<br />beginning of cleavage. 8lastoeneres traus-
<br />parent; approxirngtcly 0.5 mur rota] diarac-
<br />ter. Ateimaf and vegetal poles ~stinguixhable
<br />to uuaick~d eye; ova tulolc:cithal, cleavage
<br />meroblastio, Ova eio longer adhesive. AFA
<br />preservation cx;uses animal cells to whiten
<br />xnrl b~:ome opaque; yolk bcaomes yellow
<br />white; chorion remainR transparent.
<br />5tagc 4: 4 b]astomeresr 5 hotcrs; second
<br />cleave ,~. Bl:estameees eeFpruailreately 1.0 mm
<br />total diameter.
<br />Stage 5: 6 blastomeres, 6 hours; tLird
<br />C1eSV:lge.l3labtcuoeres ocK:upy 1.S- by O.S-tune
<br />ret`taagle on sndraal pule.
<br />Stage 6: 1S blastomeres, T baure; fourth
<br />cleavage.
<br />Stage 7: 38 blastomeras, 9 hours; fifth
<br />cleavage (Fig. IB).
<br />Stage 6: G~ b]astomeres, IO hours; sixth
<br />cleavage, 188 blaatamet+es, I1 hours; seventh
<br />cleav:~e. Large-c,•ellecl UlaStttli (tuorula); no
<br />blastotbel. Blastotneres occupy 25 percent of
<br />yolk surFactie.
<br />Stage ff: small-celled blastula (moruta), 14
<br />hDIIP9. Individual cells tilstiugnirbable; blarto-
<br />mess bulgiteg upward From round yolk taass,
<br />occupying 25 percent of yo11; surfa,ea 8lasto-
<br />mare layers progressively Nti:ntter toward pe-
<br />riphery of blastoderm; no blastncaoel.
<br />9ta:gd ltl. tnorula, 24 hours {I•ig. 1~)- Indi-
<br />vidual ells indistinguishable except with
<br />high power and chorion retnaved; bl~oderm
<br />with granular appeaeanoo; undersur~faao flak
<br />lying on flattened. surface of yolk sphere; no
<br />blas~twel. Cleavage terminated.
<br />Stage 21: blastula (epflwFy of blastoaemr),
<br />day 2.2,8 honxs; l.$ mm diameter (Fig. 1D).
<br />13)astoderm spreatlit~ over yolk where sad
<br />thinning (blastodisc). Blastocoe) present, Pcri-
<br />blast visibly as cxtlFular rim alnrrg periphery
<br />of blestoderm, beginning formation of inuar
<br />layer of yolk sac. Outer ]aver of yolk tae m
<br />be formed from ep~l:<est derived ftvrte blatao-
<br />dcrm. Blaat~adaroe ao longer bulging from
<br />yolk, capph~ under 33 percent of ephere.
<br />^eoeel
<br />Stag
<br />Uncle
<br />"rriruft
<br />layer
<br />pue+tur
<br />1'resut
<br />edge c
<br />blastol
<br />Cells +
<br />grates
<br />(carob]
<br />five tl
<br />posfdt
<br />ele8tb
<br />blast,
<br />tnvoly
<br />of yoF
<br />Sts
<br />eagle
<br />blisto
<br />Sta;
<br />irmbt
<br />~~
<br />peoxn
<br />imag
<br />end c
<br />cells,
<br />ma! +
<br />ureco~
<br />~s
<br />diasre
<br />longE
<br />im.~etc
<br />cent
<br />form
<br />clear
<br />P~
<br />meM
<br />meat
<br />St.
<br />Neuo
<br />scrub
<br />tract
<br />rB~L
<br />mom'
<br />Cher
<br />rata
<br />St
<br />emb
<br />spins
<br />pl3tr
<br />~~~.,•.
<br />
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