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ABSTRACT The purpose of this work is to find out the
reproductivephysiology of female Uca vocans borealis in the
Tanshui Mangrove Swamp of Northern Taiwan. In reproductive
season(March-August), more than eighty percent of the female Uca
vocans borealis collected in the Tanshui mangrove swamp of
northern Taiwan were found to carry eggs. On the contrary, no
eggcarrying crabs were found in nonreproductive season (October-
December).Females collected either on springtide or neaptide,
were tentatively categorizedin four groups:carried yellow,
brown, black eggs and noneggcarrying. Each category contributed
about 25%. Different developing stages of embryo were foundamong
crabs carried brown eggs. The embryos of crabs carried black
eggs nearly reached hatching stage. Therefore, it is suggested
that the spwaning and releasing of Uca vocans borealis is not
synchronized and not correlated to the tide. The incubation time
of the carried eggs was 15-20 days according to the record of
the raised crabs on the field and in the laboratory. It is
estimatedthat the reproductive cycle of Uca vocans borealis is
about 20 days. The GSI offemales of the nonreproductive season
was about a half of that of the reproductive season.The ovaries
of crab carried black eggs contained more protien and fat.
(107.3-187.4 ng/g of ovary;312.3-377.2 ng/g of ovary). The
protein content of hepatancreas of crab carried brown eggs did
not show sibnificant variation(p>0.05) during the reproductive
season. However, the crabsof nonreproductive season contained
less protein (68.57-89.9mg/g of hepatopancreas), and
nonreproductive season contained similar amounts of fat.During
reproductive, the hepatopancreas of crab carried black eggs
contained more protein and fat(102.8-148.7 mg/g of
hepatopancreas ; 102.8-346.3 mg/g ofhepatopancreas) than those
crabs carried brown or yellow eggs.The progesterone-like
substance was detected in the hemolymph of the female crabs. The
hemolymphic progesterone-like substance levels of the
nonreproductive season(0.051-0.086 ng/g of wbw) were lower than
that of reproductive season (0.121-0.464 ng/g of wbw). The
progesterone-like substance was also detested by HPLC and RIA in
the purified steroid residues of ovary, hepatopancreas and
hemolymph.The hemolymph contained least amout of progesterone-
like substance (0.003-0.520ng/g of wbw). Among ovaries, crab
carried yellow eggs had more progesterone-
likesubstance(0.117-0.521 ng/g of ovary) than crab carried
brown eggs(0.067-0.361 ng/g of ovary). The ovaries of crab
carried black eggs had least amount (0.003-0.071 ng/g of ovary).
The function of hormones of crustaceans, including
theprogesterone-like substance of Uca vocans borealis,
isdiscussed in this work.
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