REPRODUCTIVE BIOLOGY OF PUNTI, PUNTIUS
SOPHORE IN RAJHDHALA BEEL, NETRAKONA
MS Thesis
MD. ASHFAQ SADAT
Depa men o Fishe ies Managemen
Bangladesh Ag icul u al Uni e si y
Mymensingh
Decembe (2021)
(Examina ion held in No embe 2022)
REPRODUCTIVE BIOLOGY OF PUNTI, PUNTIUS
SOPHORE IN RAJHDHALA BEEL, NETRAKONA
A Thesis
Submi ed o
Bangladesh Ag icul u al Uni e si y, Mymensingh
In Pa ial Ful ilmen o he Requi emen s o he Deg ee o
Mas e o Science
in
Fishe ies Managemen
by
MD. ASHFAQ SADAT
Roll No.: 19FMJD-01M
Regis a ion No.: 43747; Session: 2014-15
Depa men o Fishe ies Managemen
Bangladesh Ag icul u al Uni e si y
Mymensingh
Decembe (2021)
(Examina ion held in No embe 2022)
REPRODUCTIVE BIOLOGY OF PUNTI, PUNTIUS
SOPHORE IN RAJHDHALA BEEL, NETRAKONA
A Thesis
Submi ed o
Bangladesh Ag icul u al Uni e si y, Mymensingh
In Pa ial Ful ilmen o he Requi emen s o he Deg ee o
Mas e o Science
in
Fishe ies Managemen
App o ed as o s yle and con en s by
P o . D . Md. Mah uzul Haque
Supe iso
P o . D . Md. Shahjahan
Co-supe iso
P o . D . Zoa de Fa uque Ahmed
Chai man, De ence Commi ee
and
Head, Depa men o Fishe ies Managemen
Bangladesh Ag icul u al Uni e si y
Mymensingh
Decembe (2021)
(Examina ion held in No embe 2022)
i
ACKNOWLEDGEMENTS
Alhamdulillah, all p aises a e due o he Almigh y Allah Rabbul Al-Amin o His g acious kindness and
in ini e me cy in all he endea ou s he au ho o le him success ully comple e he esea ch wo k and he
hesis leading o Mas e o Science.
The au ho would like o exp ess his hea el g a i ude o his esea ch Supe iso , D . Md. Mah uzul
Haque, P o esso , Depa men o Fishe ies Managemen , Bangladesh Ag icul u al Uni e si y o his
cons an supe ision, aluable sugges ions, scholas ic guidance, con inuous inspi a ion, cons uc i e
commen s, ex ending gene ous help and encou agemen s du ing his esea ch wo k and guidance in he
p epa a ion o he hesis. The au ho also exp esses his hea el g a i ude o his men o D . Saleha Khan,
P o esso , Depa men o Fishe ies Managemen , Bangladesh Ag icul u al Uni e si y o he con inuous
inspi a ion, ad ice, and good wo ds.
The au ho since ely exp esses his hea ies espec , deepes sense o g a i ude and p o ound app ecia ion
o his co-supe iso P o . D . Md. Shahjahan, Depa men o Fishe ies Managemen , and PI, Fish
Ecophysiology Labo a o y, Bangladesh Ag icul u al Uni e si y o his cons an encou agemen , a able
sugges ions, help ul c i icisms and aluable ad ice du ing he esea ch pe iod and p epa ing he hesis.
The au ho would like o exp ess his deepes espec and boundless g a i ude o he head o he depa men
P o . D . Zoa de Fa uque Ahmed and all he espec ed eache s o he Depa men o Fishe ies
Managemen , Bangladesh Ag icul u al Uni e si y o hei aluable eaching, sympa he ic coope a ion,
and inspi a ion h oughou he cou se o his s udy and esea ch wo k.
I is a g ea pleasu e o he au ho o exp ess his p o ound g a i ude and deepes app ecia ion o his
belo ed pa en s o hei sac i ices, ne e -ending p aye s and dedica ed e o s o educa e he au ho o
his le el. The au ho is also g a e ul o his wi e Mos a a Nas in Suma o he con inuous inspi a ion
and suppo h oughou his jou ney. The au ho is acknowledging he sac i ices, encou agemen ,
inspi a ion and blessing o his sis e s h oughou he whole pe iod o he s udy.
Finally, he au ho app ecia es he assis ance ende ed by he s a membe s o he Fish Ecophysiology
Labo a o y and he Depa men o Fishe ies Managemen .
The Au ho
REPRODUCTIVE BIOLOGY OF PUNTI, PUNTIUS SOPHORE IN
RAJHDHALA BEEL, NETRAKONA
19FMJD-01M
ABSTRACT
To iden i y he b eeding season o Pool ba b, Pun ius sopho e h ough obse a ion
o he gonadosoma ic index (GSI), ecundi y, oocy es diame e , and gonadal
his ology o he species and o sugges managemen ecommenda ions, he
ep oduc i e biology was s udied wi h indi iduals o he popula ion om Rajdhala
beel, Ne akona om July 2020 o June 2021. The ish specimens we e collec ed
mon hly using a seine ne . Th ee me hods we e employed o de e mine he
spawning season. I is wo h men ioning ha , he mon hly mean gonadosoma ic
index was ound highes in June. Since he mean gonadosoma ic index was highes
in June, he e o e i was opined ha he spawning ook place in June appa en ly.
Va ious de elopmen al s ages o o a ies we e classi ied conside ing hei ex e nal
ea u es and he mac oscopic iews o eggs. The s ages we e imma u e, de eloping,
ma u ing, and spawning. Ex e nal mo phology and mac oscopic obse a ion o
emale gonads showed ha he spawning season o pool ba b was be ween Ma ch
and June. The mic oscopic examina ions o gonad his ology de ec ed he p esence
o i e s ages o oocy e ma u i y which we e ea ly pe inucleolus, yolk esicle s age,
p ima y yolk s age, mig a o y nucleus s age, and p ema u e s age. Mon hly
plo ing o pe cen da a o his ological s ages e ealed ha he mos ad anced s age
de ec ed in his s udy occu ed in Ap il, May, and June. Based on his ological
in es iga ion i was e en ually concluded ha he spawning season o P. sopho e
exis ed om Ap il o June. Pos o ula o y ollicles and hyd a ed eggs we e absen
in he ma u e o a ies o e he s udy pe iod which ga e he suppo ha P. sopho e
was a synch onous single spawne . The s udy also demons a ed ha he s anda d
leng h o he younges emale ha bo e ma u e eggs was 3056 mm, and i s
gonadosoma ic index was 7.48. The ange o ela i e ecundi y was om 540 o 4352
pe gm o ma u e emales in e ms o s anda d leng h ha ing a ange om 56 mm
o 92 mm. S anda d leng h and ecundi y yielded a cubic ela ionship, he equa ion
was F= 0.0232SL2.6877 ( 2 = 0.8683). The ela ionship be ween ecundi y and body
weigh was in he o m o a s aigh line, and he es ima ed equa ion was F =
213.44BW + 125.24 ( 2 = 0.892). High alues o coe icien s o de e mina ion in bo h
cases desc ibed s ong ela ionships be ween p edic o and esponse a iables in
ecundi y es ima ion.
i
CONTENTS
CHAPTER
TITLE
PAGE NO
ACKNOWLEDGEMENTS IV
ABSTRACT V
CONTENTS VI
LIST OF TABLES VIII
LIST OF FIGURES IX
LIST OF APPENDICES X
ABBREVIATIONS XI
INTRODUCTION 1
REVIEW OF LITERATURE 8
B eeding biology o Pun ius spp. 8
B eeding biology o some o he ishes 13
MATERIALS AND METHODS 18
Sampling si e 18
Rajdhala Beel, Pu badhala, Ne akona. 18
Labo a o y wo ks 19
Collec ion o gonad and sex de e mina ion 19
Es ima ion o GSI (Gonadosoma ic Index) 20
Obse a ion o o a ian ex e nal ea u es 20
His ological examina ion 21
Leng h a sexual ma u i y 22
Es ima ion o ecundi y (F) 22
Gonad his ology 23
Da a analysis 26
RESULTS 27
Fish size 27
S anda d leng h o ishes 27
Body weigh o ishes 28
De e mina ion o spawning season 30
Gonadosoma ic index (GSI) me hod 30
Ex e nal ea u e o o a y 32
His ology o o a y 34
F equency o spawning and measu emen o egg
diame e 37
Minimum leng h a ma u i y 38
Fecundi y 39
ii
CHAPTER
TITLE
PAGE NO
Rela ionship be ween ecundi y and s anda d leng h 39
Rela ion be ween ecundi y and body weigh 40
DISCUSSION 42
SUMMARY AND CONCLUSION 47
REFERENCES 49
APPENDICES 57
iii
LIST OF TABLES
SL NO
TITLE
PAGE NO
Table 1 Time schedule in he au oma ic issue p ocesso 24
Table 2 S aining p ocedu e o his ological s udy o gonad 25
Table 3 S anda d leng h (mm) o mon hly collec ed specimens (July
2019-June 2021) 27
Table 4 Body weigh (g) o mon hly samples specimens (July 2019-June
2021) 29
Table 5 Mon h-wise gonadosoma ic index o P. sopho e (July 2019-June
2021) 31
Table 6 Mon hly ecundi y o P. sopho e 39
ix
LIST OF FIGURES
SL. NO
TITLE
PAGE NO
Figu e 1 Pun ius sopho e 6
Figu e 2 A iew o Rajdhala beel 18
Figu e 3 Map showing he s udy a ea 19
Figu e 4 A: An adul emale o Pun ius sopho e wi h isola ed ma u ed
gonad; B: Taking body weigh and gonad weigh o samples in
labo a o y 20
Figu e 5 Flow cha showing his ology p ocesses o gonad 26
Figu e 6 F equency dis ibu ions o s anda d leng h o P. sopho e 28
Figu e 7 F equency dis ibu ions o body weigh o P. sopho e 29
Figu e 8 F equency dis ibu ions o gonadosoma ic index o P. sopho e 30
Figu e 9 Mon hly changes o gonadosoma ic index o P. sopho e (July
2019-June 2021) 32
Figu e 10 Ma u ed o a y o Pun ius sopho e 33
Figu e 11 Mon hly changes in he equency o he occu ence o o a ian
ma u i y 34
Figu e 12 Ma u i y s ages om his ology o P. shopo e's gonad 35
Figu e 13 F equency occu ence o ma u i y s ages o oocy es 37
Figu e 14 Size equency dis ibu ion o oocy es o P. sopho e 38
Figu e 15 Rela ionship be ween gonadosoma ic index (GSI) and s anda d
leng h o emale ha ing ma u e gonad. Yellow do indica es he
GSI o younges adul emale ha ing 56 mm SL in his s udy 38
Figu e 16 The ela ionship be ween ecundi y and s anda d leng h o P.
sopho e du ing spawning season 40
Figu e 17 The ela ionship be ween ecundi y and body weigh o P.
sopho e du ing spawning season 41
Figu e 18 Size equency dis ibu ion o oocy es o P. sopho e. Fecundi y
was coun ed wi h he eggs igh o he a ow 41
5
possible al e na i e s a es, bu he li e his o y o a gi en species consis s o only one
o hese s a es o each li e-his o y pe iod.
Since each ish species e ol es unde a unique se o ecological condi ions, i has a
unique ep oduc i e s a egy wi h special adap a ions including ana omical
adap a ions, de elopmen al adap a ions, beha iou al adap a ions, physiological
adap a ions, and ene ge ic adap a ions.
The ep oduc i e p ocess allows species o pe pe ua e hemsel es. Almos all ishes
ep oduce sexually, hus pe mi ing mixing o he genes o he wo sexes. The
ep oduc i e p ocesses o ishes o m he basis o ea ly li e his o y s udies. The
g ea a ie y o hese p ocesses among ishes make hei s udy wo hwhile, bu also
de e mine how ea ly li e-his o y s udies o a ious ishes can be conduc ed. Fo
example, ishes ep oduce in esh and ma ine wa e s, ha e ex e nal and in e nal
e iliza ion, ha e sho annual ep oduc i e pe iods, o p oduce game es a egula
in e als h oughou he yea . This s udy summa izes he ep oduc i e pa e ns o
ishes, wi h an emphasis on how hese pa e ns a ec ea ly li e-his o y s udies.
In li e his o y o a ish species wo majo e en s a e e y impo an . One is
ep oduc ion ano he is ec ui men . In ishe ies s udies, he pa icula e en o
in e es in he ep oduc i e cycle o ish species is ime o spawning, when ully
de eloped game es a e eleased. S udy abou ep oduc i e biology o any ish is
essen ial o e alua ing he condi ion o i s s ock, li e his o y, cul u e p ac ice and
ac ual managemen o i s ishe y (Lagle , 1956; Doha and Hye, 1970). Po en iali y
o ep oduc ion o a popula ion is one o he basic exigencies o designa e he
indi iduals o ha popula ion in espec o hei gonadal condi ions (Jhing an and
Ve ma, 1972). I is impo an o assess he yea ly b eeding cycle o a ish species o
success ul ish cul u e. Spawning o ish occu s du ing a pa icula phase o
ep oduc i e cycle. Some o hem b eed once annually while some a egula
in e als h oughou he yea . Knowledge o gonadal de elopmen and he
spawning season o a species allow subsequen s udies on spawning equency o
i s popula ion, which is impo an o i s managemen . Ano he iden i ica ion o
he b eeding ac i i y o an exploi ed ish species p o ides managemen op ion o
p o ec ion o i s spawning s ocks (La oche and Richa dson, 1988). Rep oduc i e
6
pa ame e s do no p o ide di ec e idence o s ock s uc u e, bu do p o ide
in o ma ion o assis in unde s anding biological p ocesses ha may be esponsible
o main aining he unde lying s ock s uc u e o a species. The mos impo an
aspec o ep oduc ion is ecundi y es ima ion. Rep oduc i e s udies ha e been
impo an componen o he biological basis o managemen o ish and ishe ies.
This s udy is unde aken o de e mine he spawning season, o es ima e ecundi y,
he size a sexual ma u i y, age and pa e n o egg elease o pun i ish.
The ish species, Pun ius sopho e, one o he Cyp inid ishes unde he amily
Cyp inidae a e mos ly a ailable in ponds, small s eams, beels, inunda ed ields
and weedy di ches (Talwa and Jhing an, 1991a; Rahman, 1989, 2005) and la gely
dis ibu ed in Asia: Pakis an, India, Nepal, Bangladesh, Myanma and Yunnan,
China (Talwa and Jhing an, 1991b), Bhu an and A ghanis an (Pe , 1999).
Mo eo e , hey also emain in domes ic aqua ia and become ma u e a 7 o 8 cm
(Talwa and Jhing an, 1991a).
The English name o his ish species is pool ba b and is locally known as Ja i pun i
in Bangladesh. This is one o he mos common, small-sized ishes caugh in la ge
quan i ies om a ious eshwa e habi a s. Mo phologically, he body o Pun i is
elonga ed and comp essed la e ally wi h poin ed head. Lowe jaw is longe . The
numbe o scales on he la e al line se ies a e 20 o 25. The numbe o scales abo e
he la e al line is 8 o 10. Scales numbe below he la e al line is 3 o 4. Scales numbe
on he la e al line se ies men ioned by o he w i e s a e: 24 - 26 scales (Rahman,
2005), 22-27 scales (Talwa and Jhing an, 1991a).
Figu e 1 Pun ius sopho e
7
This small ish is well ega ded as a quali y ood con aining high amoun o Vi - A,
p o ein, zinc, calcium and mine al e c. (Boga d e al., 2015). In spi e o ha ing
eno mous economic and nu i ional impo ance o his species o he u al and
u ban people as well as he ishing communi y, adequa e s udies on hei
ep oduc i e biology, namely spawning season, minimum leng h a ma u i y and
ecundi y o his species a e needed o app op ia e managemen .
Rep oduc i e biology is an impo an pa ame e o de e mine he quali y and
quan i y o ish s ock in a na u al wa e body as well as o de e mine he
ep oduc i e po en ial (King, 2013). Success ul ep oduc ion and ec ui men
ensu e he sus ainabili y o a ish s ock in a na u al wa e body.
As pun i is sel - ec ui ing species in Rajdhala beel, a biological s udy can help o
make decisions o main aining i s sus ainabili y unde he condi ions o clima ic
change and na u al p oduc i i y (Rahman and Haque, 2008). I is e y impo an
o know he e ec s o en i onmen al a iabili ies and na u al p oduc i i y on
ep oduc i e biology o his ish. Knowing he biology, he indings o he cu en
s udy will be help ul in de eloping good managemen s a egies as well as ge ing
mi iga ion measu es o inc ease he p oduc i i y o pun i in o de o main ain
op imum s ock and sus ainable highe p oduc ion bene i ing he poo ishe ies
s akeholde s a ound he a ea o a g ea e ex en .
In iew o he abo e ac s, he p esen s udy was unde aken on he ep oduc i e
biology o Pool ba b (P. sopho e) wi h he ollowing objec i es:
1. To de e mine he mon hly gonadosoma ic indices o he species
2. To de e mine he ecundi y o he species
3. To es ima e he spawning season o he species
8
REVIEW OF LITERATURE
Be o e conduc ing any expe imen , i is impo an o analyse p e ious esea ch
wo k ele an o he in ended subjec . The ep oduc i e biology o pun i is no well
documen ed, bu he e is a ew esea ch on ce ain elemen s o he biology o
se e al small ishes. The men ioned li e a u e has limi a ions because he e a e ew
connec ions be ween i and he cu en s udy's scope and objec i es. Howe e , he
sugges ed wo k's associa ed li e a u e is examined. Despi e he abundance o
esea ch on spawning equency, b eeding season, and ecundi y o se e al ishes,
knowledge on he ep oduc i e biology o Pun ius sopho e is sca ce. The ollowing
in o ma ion on he spawning equencies, b eeding season, and ecundi y o ela ed
ishes ha has been ga he ed om p e ious s udies up o he p esen :
B eeding biology o Pun ius spp.
Acco ding o Bhuiyan (1964), du ing he monsoon season, Pun ius sopho e
ep oduces. Male ish g ow a b igh ed band along he middle o bo h lanks
du ing he b eeding season. In emale ish, his is less ob ious.
Sha i and Quddus (1974a) obse ed ha pun i, Pun ius s igma, wi h a sho li e cycle,
li ed only o a yea o wo and a ained ma u i y e y ea ly. The sex a io indica ed
ha 60% o he ish we e males and males we e mo e nume ous a lowe leng h-
g oups (4-7 cm) and emales in he highe g oup (8 cm and abo e).
In ano he s udy, Sha i and Quddus (1974b) s udied he ecundi y o common pun i,
Pun ius s igma, om Bangladesh wa e s and no ed ha he ecundi y a ied om
1,242 o 6,831. The ela ionship be ween ecundi y and gonad weigh was mo e
signi ican han ha o ecundi y wi h o he ac o s.
Mus a a (1991) obse ed he ecundi y and spawning equency o Pun ius chola in
pond condi ion and epo ed ha he ecundi y o Pun ius chola was 1,404 o 1,872
wi h an a e age o 1,581 ± 142. He also obse ed ha he species had a leas wo
dis inc g oup o eggs in he o a y wo b eeding seasons.
9
In ano he s udy, Sobhana and Nadi (1974) obse ed he b eeding season o
Punlius sa ana in Veli lake, T i and um ex ended om la e May o No embe . Peak
spawning occu ed in July and Oc obe . Gonadosoma ic index o bo h sexes
showed he highes alue in June and Sep embe and he ish ma u ed a 183 mm
in o al leng h. The o a diame e equency in e ed ha hese ishes could b eed
wice a yea (May and Sep embe ).
The ma u i y and ecundi y o Pun ius sa ana we e also s udied by Sinha (1975) a
Loni Rese oi , India. He epo ed he p esence o a single ba ch o ma u e eggs
wi h a mean model size o 99 mm. The cycle o ma u a ion and coe icien o
ma u a ion indica ed he spawning season o his ish was July-Augus . Fecundi y
o he species has been es ima ed o ange om 58.327 o 139.984 wi h a o al leng h
o 230 o 326 mm. The ecundi y o Pun ius sa ana wi h a leng h o 155 o 250 mm
was ound o ange om 18,925 o 78,929. The ma hema ical ela ionships be ween
ecundi y and o al leng h, ecundi y and body weigh , and ecundi y and o a y
weigh we e linea , whe eas a cu ilinea ela ionship was no ed be ween
ecundi y and he s anda d leng h o he ish.
Acco ding o S i as a a (2003), maximum alue o gonadosoma ic index was 1.849
o male and 12.075 o emale in he mon h o July. The leng h a ma u i y was
measu ed as 58 mm o he male and 66 mm o he emale o Pun ius sopho e,
which was disco e ed o be a single spawne in a yea . Fish leng h, ish weigh ,
o a y leng h, and o a y weigh we e ound o ha e linea ela ionships wi h
ecundi y. Fecundi y was signi ican ly co ela ed wi h o a ian weigh ( 2 =
0.95479), ish leng h ( 2 = 0.91047), and ish leng h ( 2 = 0.88959) bu no wi h o a y
weigh ( 2 = 0.73668) o ish leng h ( 2 = 0.88959). This demons a es ha o a ian
and ish leng h and weigh bo h a ec e ili y.
Mi a e al. (2005) in es iga ed leng h weigh ela ion, ep oduc i e cha ac e s and
condi ion o Pun ius sopho e (Hamil on) om a loodplain we land in Wes Bengal.
This s udy ound ha while males conside ably de ia ed om cube law, emales
ollowed i . The emales ma u ed when hey we e 6l-65 mm in leng h. The gende
a io was sligh ly in women's a ou (a . 1:1.2). The ish had a ecundi y o be ween
759 (85 mm and 7.66g size) and 29.650 (113 mm and 25.25g size). The diame e o
10
he o a a ied om 0.l6 o 0.86 mm. The ish's spawning season las ed om
Feb ua y o Augus .
Ma ina (2006) s udied he ep oduc i e biology and Pun ius sopho e o a pe ennial
wa e body in Bangladesh. She sugges ed ha he spawning seasons o Pun ius
sopho e we e s a ed om Ap il and con inued up o Sep embe .
Pun ius sopho e was a single spawned and i s spawning equency o s a egy was
synch onous ype. The minimum s anda d leng h (SL) a ma u i y was 51 mm, and
he mean SL a i s ep oduc ion es ima ed om he Logis ic model was 66.5 mm
o emales. Fecundi y es ima es we e 3494 o 31723 eggs om emales o 23 o 91
mm s anda ds leng h. The ela ions be ween ecundi y (F) and s anda d leng h
(SL), and be ween ecundi y and body weigh (BW) we e es ima ed as F =
0.00109SL. ( 2 = 0.708) and F = 1105.645BW - 1709.041 ( 2 = 0.948) espec i ely.
Ta eque e al. (2008), s udied he aspec s o biology o Pun ius sopho e sampled om
Mou i i e , Khulna, Bangladesh. The mean weigh o he bilobed gonads (WG)
was 1.36 0.438 g. A he an e io , cen al, and pos e io po ions o bo h lobes, he
mean o a diame e was 6.50.51 mm, 6.50.68 mm, and 6.310.56 mm, espec i ely.
Fecundi y anged om 743 o 4013. (LT: 7.0-9.9 cm, W: 5.3-14.3 g). Posi i e bu
shaky connec ions exis ed be ween LT-F and W-F. The WG-F link was ex emely
solid. In Augus , he GSI was 15.25 ± 3.80.
Mannan e al. (2010) obse ed he gonad de elopmen and ep oduc i e cycle o
Pun ius ilamen osus and obse ed ha he spawning mon h o No embe and Ap il
coincided wi h No h-Eas Monsoon (No embe ) and Sou h-Wes Monsoon (Ap il)
in India. The g oss mo phology o P. ilamen osus showed 6 o a ian s ages. The
his ological appea ance o he o a ies showed en s ages (oogonia o a e ic
oocy es). The es es o P. ilamen osus showed i e mo phological s ages each. The
p og ession o gonadal cycle o P. ilamen osus collec i ely e ealed ha he
ma u a ion o males coincided wi h he ma u a ion o emales du ing he spawning
pe iod.
Bi hy e al. (2013) es ima ed he ecundi y o Ja pun i (Pun ius sopho e) om he
expe imen al ponds o he Field Labo a o y Complex, Facul y o Fishe ies,
11
Bangladesh Ag icul u al Uni e si y (BAU), Mymensingh. The es ima ed ecundi y
o he h ee ish g oups was 7951 o 17670; 8135 o 23053; and 12461 o 15105 eggs,
wi h a mean gonadosoma ic index (GSI) o 23.44 2.50; 30.47 4.52; and 28.43 2.99,
espec i ely. The associa ion be ween ecundi y and o al leng h was linea , wi h
Ln F= 1634 ln TL-1972, Ln F= 119405 ln TL-273.53, and Ln F= 1831.6 ln TL+ 825.31,
o h ee g oups espec i ely. The linea eg ession equa ion be ween body weigh
and o al leng h was Ln W= 2.2128 ln TL- 0.7048, Ln W= 2.0207 ln TL+ 0.3493, and
Ln W= 1.4438 ln TL+ 5.5694, espec i ely, in 3 g oup. The linea eg ession equa ion
be ween body weigh and ecundi y was F= 656.84 W+199.96, F= 438.16 W+2470,
and F= 1116.1 W-3433.5, espec i ely. The o al leng h and body weigh we e
closely linked wi h ecundi y, sugges ing ha P. sopho e was a mode a ely ecund
ish.
Using di ec obse a ion o sexual ea u es (e.g., gonadosoma ic index) and he
indi ec me hod o ela i e g ow h, Ahamed e al. (2015) de e mined he size o he
emale Pun ius sopho e a sexual ma u i y in he Old B ahmapu a Ri e , No h
Eas e n Bangladesh. Based on he link be ween s anda d leng h and gonadosoma ic
index, emale P. sopho e was de e mined o be 4.2 cm s anda d leng h a sexual
ma u i y. Rela i e g ow h o o k leng h o s anda d leng h, on he o he hand,
indica ed a changeo e poin a 4 cm s anda d leng h, indica ing emale P. sopho e
size a sexual ma u i y.
Acco ding o Hossain e al. (2012) in he Padma Ri e , Pun ius sopho e emale size
a i s ma u i y was calcula ed o be 5.00 cm TL. Fecundi y was calcula ed using
specimens g ea e han 5.00 cm TL. Be ween 1580 o 16590, he mean o al ecundi y
anged om 5300 o 2700. To al leng h and o al ecundi y we e ound o be
posi i ely exponen ially co ela ed ( 2 = 0.421). In he Padma Ri e , ela i e
ecundi y a ied om 466 o 4036 (mean 1100 580).
Lange e al. (2013) iden i ied he b eeding pe iod o Pun ius sopho e is om July-
Augus . Pun ius sopho e was ound o con ain oocy es in se en s ages. Th oughou
he en i e ep oduc i e cycle, oogonia we e p esen .
12
Fecundi y o Pun ius sopho e was es ima ed by Kan e al. (2016) o be be ween 1560
and 2314 eggs, wi h a mean o al leng h o 5.5 cm and a mean body weigh o 5.47
gm. The absolu e ecundi y anged om 6106.73 o 6942.35 eggs, whe eas he
ela i e ecundi y a ied om 390.85 o 480.18 eggs pe ish. Absolu e ecundi y has
a s ong ( 2=0.809) co ela ion wi h o a ian weigh bu a weak ( 2=0.047) and
mode a e ( 2=0.216) co ela ion wi h o al leng h and body weigh . The e o e, i
would seem ha o a ian weigh had a g ea e in luence on e ili y han did body-
ela ed ac o s. A s aigh -line link be ween ela i e and absolu e ecundi y and
body pa ame e s has been ound du ing he cu en in es iga ions.
Choudhu y e al. (2015), s udied he ep oduc i e ea u es o Pun ius sopho e om
he i e s o T ipu a, India. Es ima ed b eeding season was July-Augus . Fecundi y
was es ima ed du ing he peak spawning season (July) and he ela i e ecundi y
obse ed was 4073±310 g-1 body weigh . The a e age GSI eco ded in male and
emale popula ions was highes du ing July mon h (14.22±3.9 and 20.88±4.55%
espec i ely)
Hasan e al. (2018) iden i ied he b eeding season o Pool ba b h ough obse a ion
o he gonadosoma ic index (GSI), ecundi y, oocy es diame e , and gonadal
his ology o he species. This s udy compa ed wo popula ions o Pool ba bs (one
om Gazipu and he o he om Jesso e). The highes GSI alue was 15.43 2.20 in
Ap il a Gazipu , while i was 15.60 1.74 in June a Jesso e. The maximum e ili y
(5053 878.27) was obse ed in Gazipu in Ap il, while he highes ecundi y (5433
968.26) was eco ded in Jesso e in June. Du ing Ma ch, his ology o Pool ba b's
o a y e ealed he p esence o ea ly and la e pe i nucleola s age oocy es,
indica ing imma u e oocy es. Pool ba b spawning season uns om Ma ch o July,
wi h a peak in Ap il o May o he Gazipu egion and May o July o he Jesso e
egion, acco ding o his ological da a. Finally, hese indings sugges ha b eeding
season a ies om egion o egion due o en i onmen al and o he a iables.
13
B eeding biology o some o he ishes
Mookhe jee and Basu (1946) who s udied he li e his o y o Amblypha yngodon mola
was epo ed ha he b eeding season o he ish las ed om May o Oc obe and a
single emale can lay 500 eggs a a ime.
Qayyum and Qasim (1964) s udied he biology o eshwa e ishes including
Ba bus s igma om Indian wa e s and ound he o a ies o his ish con ained only
once du ing he b eeding season.
Ka amchandani e al. (1967) s udied he ecundi y o To o in India and es ima ed
43,410 numbe s o eggs in a specimen o 750 mm leng h and also es ima ed 30,420
eggs om a specimen o 625 mm o al leng h. He epo ed ha he ecundi y o T.
o would inc ease wi h he inc ease o body leng h.
Ras ogi and Saxena (1968) s udied annual changes in he o a ian ac i i y o he ca
ish Mys us enga a and ound nine s ages o de elopmen showing peak
ma u a ion om Ap il o Augus .
Ka im and Hossain (1972) s udied he biology o Mas acembelus pancalus (Spiny Eel,
Hamil on) in a i icial ponds. They ound he ecundi y a y om 1,296 o 3,246
wi h he mean 2,013. The co ela ion coe icien o he o al leng h o M. pancalus
was =0.93. A s aigh - line eg ession (Ye) o ecundi y (Y) on weigh （X) o o a y
o M. pancalus was calcula ed o be Ye = 439.19+1.786 X.
Dewan (1973) obse ed he spawning season o mola o las om Ap il o
No embe in he lake o Bangladesh Ag icul u al Uni e si y Campus. The peak
pe iod o spawning occu ed in Augus and Sep embe . The ecundi y o ish
anged om 1,021 o 13,815. The numbe o eggs inc eased wi h he inc ease in
leng h o he ish.
Malho a e al. (1978) s udied o a ian cycle and spawning season o Ophiocephalus
punc a us, inhabi ing Jammu wa e s, India and epo ed six well de ined s ages o
ma u a ion and he ish had a p olonged spawning season ex ending om May o
Augus .
14
Acco ding o P asad e al. (1979) he male and emale Mac ogna hus aculea us
become sexually ma u e a leng h o 15.5 cm (abou 15 gm) and nea ly 18 cm (22
gm) espec i ely. The ecundi y es ima ed by hem was anging om 210 o 1828.
De-sil a and Chand asoma (1980) s udied he ep oduc i e biology o Sa o he odon
mossambicus, an in oduced species, in an ancien a man-made lake in S i Lanka.
The ep oduc i e biology o Sa o he odon mossambicus (Pe e s), a species exo ic o
S i Lanka, was es ablished in Pa ak ama Amud a an ancien man-made lake. Males
ma u e a a leng h o 27.5 cm and emales a a leng h less han 15 cm. S. mossambicus
b eeds h oughou he yea wi h ou possible peak pe iods, which coincide wi h
he ail end o he monsoon and in e monsoon ains. The egg diame e dis ibu ion
indica es he p esence o ese e oocy es and yolked oocy es, he la e alling in o a
single mode be ween 1.2 o 3.6 mm. Fecundi y a ied be ween 360 and 1775 o ish
anging in leng h om 22 o 31.9 cm and 145 o 538 g in weigh .
Mus a a e al. (1980) s udied on ood, eeding habi and ecundi y o eshwa e
Pe ch Nandus nandus (Hamil on), meni ish (Bangladesh). The ecundi y anged
be ween 7,381 eggs o a ish wi h body leng h o 9.7 cm and 46,222 eggs o a ish
wi h body leng h o 13.5 cm. B eeding season anged om June o July.
Ma hema ical ela ionship be ween body leng h- ecundi y and weigh - ecundi y
we e ound o be linea .
The ecundi y Colisa ascia a was s udied by Banu e al. (1984), who men ioned ha
his ish spawned only a a pa icula ime o he yea , i.e., om Ma ch o Ap il. The
g a id emale o his ish con ained ma u e eggs, which anged om 5,123 o 13,450.
Rela ionship be ween ecundi y and gonad weigh was mo e signi ican han ha
be ween ecundi y wi h o he s ac o s.
Mus a a (1991) obse ed he ecundi y and spawning equency o Kholisa in pond
condi ion and obse ed ha he ecundi y o Kholisa was 1,578 o 2,684 wi h an
a e age o 2,175±431. He s a ed ha he species a leas wo dis inc g oup o eggs
in he o a y indica ing wo b eeding seasons.
Kabi e al. (1998) de e mined he ecundi y and gonadosoma ic index o chapila,
Gudusia chap a and obse ed ha he male ish a ained sexual ma u i y a 7.7 cm
21
His ological examina ion
Con en ional his ological p ocessing began wi h p ese a ion o o a ies. P ese ed
o a ies we e immed and o ien ed, dehyd a ed, in il a ed wi h pa a in, and
o med in o blocks o issue su ounded by suppo ing medium.
These blocks we e hen sec ioned and slices we e moun ed on glass slides and
s ained. Once a co e slip was added, he sec ions we e iewed mic oscopically.
Pun i o a ies we e used o his ological examina ion a e he ollowing p ocedu e:
1. A ans e se segmen o abou 4 mm hick om he middle pa o le o a y
was aken.
2. Dehyd a ion o o a ian segmen was achie ed by he passage o issue piece
h ough a se ies o e hyl alcohol solu ions in he oom empe a u e
acco ding o he ollowing schedule in which a epea ed s ep mean a change
o medium.
3. Imp egna ion o issue wi h benzene, a sol en o pa a in was done wice
successi ely o 1 hou each o emo e aces o alcohol in o de o ha e
consis en pa a in block.
4. In il a ion by mel ed pa a in a 600 °C was done wice consecu i ely o a
pe iod o 40 minu es each.
5. Following dehyd a ion, cleaning and in il a ion by mel ed pa a in, o a ian
segmen was placed in a clay mold wi h mel ed pa a in o embedmen .
Ca e was gi en o ensu e o ien a ion o issue wi hin he esul block, which
was allowed o cool wi hin he mold.
6. The pa a in block was cu o se ial sec ions wi h a hickness o 5 μm each
using a mic o ome and he sec ions we e moun ed on clean and adhesi e
coa ed slide, he slide was placed in ack wi hin an o en and hea ed
o e nigh a 200 °C.
7. The slides moun ed wi h gonadal sec ions we e s ained by haema oxylin
and eosin.
8. Finally, Canada balsam, a moun ing medium was applied and co e slip
was lowe ed in o place, comple ely co e ing he sec ions.
22
9. The sec ions we e examined unde ligh mic oscope (x 200). A leas h ee
sec ions we e examined o eco ding he occu ence o a ious his ological
s ages o o a y.
Leng h a sexual ma u i y
Female classi ied in o a ious spawning s ages by o a ian his ology we e used o
de e mine minimum leng h a sexual ma u i y. Fo he de e mina ion o minimum
leng h a ma u i y, s anda d leng h and GSI alues o all emale specimens we e
plo ed and emale wi h he lowes s anda d leng h ha ing inal spawning s age
was conside ed capable o spawning and i s s anda d leng h was he minimum
s anda d leng h a ma u i y o he popula ion.
Es ima ion o ecundi y (F)
Fecundi y was es ima ed using he olume ic me hod (Diaz e al., 1983). Weigh o
o a ies we e aken using he elec onic balance. Po ions o o a ies weighed and
placed in Gilson’s luid and shaken pe iodically o elease he oocy es. A e
suspending he oocy es in a olume o (1-1.5 L) wa e subsamples we e aken. In
each subsample, oocy es we e coun ed a 50x magni ica ion. The eliabili y o sub-
samples es ed h ough analysis o a iance (ANOVA) es . The o al numbe o
oocy es in he o a ies will be es ima ed using he ollowing o mula:
N= (V
V1)n × (W
W1)
Whe e, V= Volume o sample, V1= Volume o subsample, W= Weigh o o a y, W1=
Weigh o po ion o o a y, n is he numbe o oocy es in he sub-sample.
The e a e se e al me hods o he es ima ion o ecundi y o ish o which a e ac ual
coun ing me hod was ound o be he mos accu a e one. Bu his me hod is e y
edious and ime consuming and o ce ain ex en a he impossible in case o high
ecund ishes. When he ac ual coun ing o eggs is imp ac icable, app oxima e
ecundi y may be ob ained by one o he ollowing me hods as ou lined by (Lagle ,
1952).
a) Volume ic me hod b) G a ime ic me hod c) Von Vaye me hod
23
Volume ic me hod and Von aye me hod ha e been ound o be sui able o
ela i ely la ge eggs. Bu he eggs o P. sopho e a e compa a i ely smalle and which
may lead o e o in he es ima ion o ecundi y by Von aye me hod and
olume ic me hod. G a ime ic me hod was ound o be mo e e icien han hose
o o he me hods and ga e ai ly accu a e esul s. The g a ime ic o weigh
me hod has been success ully used by Doha and Hye (1970), Sha i and Quddus
(1974) e c. The e o e, g a ime ic me hod was hough , may o e he bes
possibili y o minimizing e o due o i s simple and easy sampling echnique.
Fecundi y is de ined as he numbe o oocy es shed by a emale in a spawning
season was es ima ed g a ime ically. In his me hod, p io o es ima ion, oocy es
om samples (0.0001 g) ob ained om h ee po ions (an e io , middle and
pos e io ) o i e o a ian lobes andomly we e coun ed and measu ed o de e mine
whe he hey had signi icance di e ences be ween loca ions. Resul s showed ha
oocy es we e uni o mly dis ibu ed, and in he succeeding analysis, sample was
aken om he middle po ion. A sec ion o abou 4 mm long was cu om middle
pa o he igh o a y, weigh ed o nea es 0.0001 g (gw) a e emo al o o malin
om he o a y su ace wi h issue pape , and pu in o a Pe i dish wi h a small
amoun o wa e . All he eggs we e sepa a ed om each o he wi h needles and
measu ed along hei longes axis unde s e eomic oscope. A equency
dis ibu ion o egg size by 1 mμ in e al was cons uc ed, he numbe o eggs in he
la ges modal g oup, b, was summed. Fecundi y, F was calcula ed using he
ollowing o mula:
F= B × GW
gw
Whe e,
F = Fecundi y o ish, GW = Gonad weigh , B = Numbe o eggs in sample and
gw = Sample weigh
Gonad his ology
To ge solid e idence o he indings, his ology o emale gonads was done o
de e mine he gonadal de elopmen . His ology p ocess was done a Ecophysiology
24
Labo a o y, Depa men o Fishe ies Managemen , Bangladesh Ag icul u al
Uni e si y.
3.2.7.1 P ocess o gonad his ology:
His ological p ocesses we e unde aken a he Fish Ecophysiology Labo a o y,
Depa men o Fishe ies Managemen , Bangladesh Ag icul u al Uni e si y. The
gonad o each ish was p ese ed in 10% bu e ed o malin wi h labeled ials o
u he s udy. The p ese ed samples a e cu ing in o squa e size we e aken ou
in a pe o a ed plas ic holde , which was co e ed by pe o a ed s eel pla es.
Cleaning, in il a ion and dehyd a ion p ocess will be ca ied ou in an au oma ic
issue p ocesso using a se ies o alcohol o inc easing concen a ions, wo changes
o xylene and inally h ough mol en wax ( h ee se ies) as men ioned in Table 1
Time schedule in he au oma ic issue p ocesso
Pa a in embedded blocks we e cu by mic o ome kni e a 4-5 µm size and le he
sec ions in o a wa e ba h a a empe a u e o 40 ºC. The sec ions we e placed on a
glass slide and kep o e nigh on a slide d ie ho pla e a a empe a u e o 20 ºC.
Then he sec ions we e s ained ou inely wi h haema oxylin and eosin (Humason,
1962) as pe he schedule gi en in Table 2. The consecu i e s eps o conduc ing
his ology o gonad o P. sopho e a e demons a ed in Figu e 5.
Table 1 Time schedule in he au oma ic issue p ocesso
Sl. No.
S eps o p ocess
Time (hou )
P ocess
1
50% Me hyla ed spi i
1
Dehyd a ion
2
80% Me hyla ed spi i
2
3
100% Me hyla ed spi i
2
4
100% Me hyla ed spi i
2
5
100% Me hyla ed spi i
2
6
100% Alcohol
2
7
100% Alcohol
2
8
Xylene
2
Clea ing
9
Xylene
1
10
Mol en wax
1
In il a ion
11
Mol en wax
2
12
Mol en wax
2
To al
21
25
Table 2 S aining p ocedu e o his ological s udy o gonad
Sl. No.
S aining p ocess
Solu ion
Times (min)
1
2
Clea ing
Xylene
Xylene
3
3
3
4
5
6
Rehyd a ion
100% Alcohol
100% Alcohol
95% Alcohol
870% Alcohol
2
2
2
2
7
Running ap wa e
5
8
S aining
Haema oxylin
1 dip
9
Running ap wa e
25
10
Coun e s ain
Eosin
1
11
12
13
14
Dehyd a ion
70% Alcohol
95% Alcohol
100% Alcohol
100% Alcohol
1
2
2
2
15
16
Clea ing
Xylene
Xylene
2
2
26
Figu e 5 Flow cha showing his ology p ocesses o gonad
Da a analysis
Mic oso Excel 2019 (Mic oso Co po a ion, 2020) was used o abula e he aw
da a and analysed using he R p og amming language (R Co e Team, 2021). The
analyses we e done using R-S udio (RS udio Team, 2022), and ggplo 2 (Wickham,
2016) package was used o make g aphs and cha s. A one-way ANOVA (Analysis
o Va iances) was pe o med o de e mine whe he he e we e signi ican
di e ences in body indices be ween mon hs. The Duncan's Mul iple Range Tes
(DMRT) was u ilized o de e mine he di e ences (Duncan, 1955).
The models o eg ession ega ding di e en ela ionships we e compa ed and he
bes model we e selec ed o measu ing he dependencies o ecundi y. The
ela ionships be ween bodyweigh and s anda d leng h we e measu ed and ela ed
analysis we e done in R-s udio IDE. R-sc ips o da a analysis has been p o ided
in o he Appendix -2.
P ese ed gonads
Taking in pe o a ed plas ic holde
Au oma ic issue p ocesso
(Dehyd a ion, cleaning, in il a ion p ocess)
Pa a in embedded block (Embedding)
Cu ing in o 5 µm hick sec ions (Sec ioning)
Wa e ba h o 1-2 minue s @ 40 °C
Placing he sec ions on glass slides
Slide d ye
(D ying he slides o e nigh @ 20 °C
Rou ine s aining wi h s ains (haema oxylin and eosin)
Moun ing on glass slides, moun ing he sec ions on glass slides using Canada
balsam and co e ing wi h a co e slip
Examina ion unde mic oscope and keeping pho og aphic eco ds.
27
RESULTS
Fish size
S anda d leng h o ishes
S anda d leng h o collec ed ishes anged om 49 o 96 mm o e he s udy pe iod
Table 3 and Figu e 6). Fish specimens collec ed on June 2021 we e la ges (P < 0.01)
in size in e ms o s anda d leng h anging om 58-87 mm and 61.00-96.00 mm
espec i ely. Fish samples caugh on Ma ch 2021, Ap il 2021, May 2021 and July
2020 we e medium in e ms o s anda d leng h a ied om 56.00–72.10 mm, 56-82
mm, 58 - 87 mm and 55 – 82 mm espec i ely. On o he mon hs, s anda d leng h
anged om 52.50–59.00 mm in Janua y-2021, 49.30–61.50 mm in Augus , 50.80–
60.60 mm in Sep embe 2020, 50.60–78.00 mm in Oc obe 2020, and 49–70 mm in
Decembe 2021 which we e s a is ically smalles (P <0.01) h oughou he s udy
pe iod.
Table 3 S anda d leng h (mm) o mon hly collec ed specimens (July 2020- June
2021)
Mon hs
Min.
SL
Max.
SL
Mean
SL
SD
No o
emale ish
F alue
LSD
(5%)
Jan
52.50
59.00
55.64d
0.16
20
42.454
4.95
Feb
50.80
66.00
57.94cd
0.46
20
Ma
56.00
72.10
66.59b
0.47
22
Ap
56.00
82.00
69.38b
0.77
13
May
58.00
87.00
66.33b
0.69
24
Jun
61.00
96.00
83.18a
0.79
28
Jul
55.00
82.00
65.10b
0.76
21
Aug
49.30
61.50
55.24d
0.34
22
Sep
50.80
60.60
55.12d
0.27
20
Oc
50.60
78.00
55.62d
0.66
15
No
51.07
77.00
60.59c
0.91
20
Dec
49.00
70.00
57.45cd
0.56
20
SL: S anda d Leng h; SD: S anda d De ia ion; LSD: Leas signi ican di e ence;
In a column igu e wi h same le e do no di e signi ican ly whe eas igu es wi h
dissimila le e di e signi ican ly (as pe DMRT).
28
Figu e 6 F equency dis ibu ions o s anda d leng h o P. sopho e
Body weigh o ishes
Du ing he sampling pe iod, he body weigh o ish specimens cap u ed anged
om 3.8-19.5 g (Table 4 and Figu e 7). Specimens caugh in Augus 2020, Sep embe
2020, Oc obe 2020 and Decembe 2020 had he lowes a e age body weigh wi h
one pe cen le el o signi icance (P < 0.01) (Table 4). Fish samples collec ed in
No embe 2020, Feb ua y 2021 and Ma ch 2021 comp ised medium weigh anging
om 4.59-10 g, 5.37-8.66 g and 5.35-9.19 g espec i ely, hough he e we e some
la ge and small ish bu hese we e ew in numbe . Fish sample collec ed on July
2020, Ap il 2021, May 2021, June 2021 and we e la ge in weigh which ange a ied
om 4.6-15.75 g, 5.84-15 g, 6.34-17 g and 7.65-19.50 g espec i ely. Among he
specimens wi h high body weigh specimens om June 2020 we e s a is ically
highe han all o he mon hs (p < 0.01).
29
Table 4 Body weigh (g) o mon hly samples specimens (July 2020-June 2021)
Mon hs
Min. BW
Max. BW
Mean BW
SD
No o
samples
F
alue
LSD
(5%)
Jan
5.07
6.43
5.89de
0.34
20
48.268
1.73
Feb
5.37
8.66
6.54cde
0.94
20
Ma
5.35
9.19
7.51c
1.18
22
Ap
5.84
15.00
9.74b
3.15
13
May
6.34
17.00
10.06b
2.92
24
Jun
7.65
19.50
15.77a
3.14
28
Jul
4.66
15.75
9.00b
3.10
21
Aug
4.48
6.32
5.74de
0.62
22
Sep
4.00
7.30
6.03de
0.72
20
Oc
4.65
9.95
5.83de
1.20
15
No
4.59
10.00
7.17cd
2.27
20
Dec
3.84
9.00
5.50e
1.37
20
BW: Body Weigh ; SD: S anda d De ia ion; LSD: Leas signi ican di e ence;
In a column igu e wi h same le e do no di e signi ican ly whe eas igu es wi h
dissimila le e di e signi ican ly (as pe DMRT).
Figu e 7 F equency dis ibu ions o body weigh o P. sopho e
30
De e mina ion o b eeding season
The mon h-wise gonadosoma ic index, ex e nal ea u es, ecundi y o P. sopho e
we e de e mined and es ablished he ela ionship be ween s anda d leng h-
ecundi y, body weigh - ecundi y o s udy he ep oduc i e biology o his species.
O a ian de elopmen s we e obse ed o de e mine he b eeding season.
Gonadosoma ic index (GSI) me hod
The gonadosoma ic index, he indica o o he s a us o gonadal de elopmen and
ma u i y o indi iduals o expe imen al species, was calcula ed o ish P. sopho e
du ing July 2020 o June 2021. The equency dis ibu ions and he alues o
gonadosoma ic index o ish a e shown in Figu e 8, and Table 5.
Figu e 8 F equency dis ibu ions o gonadosoma ic index o P. sopho e
The GSI alues in he mon h o Ma ch, Ap il, May, June and July we e anged om
4.63-14.45, 8.12-13.57, 8.78-18.10, 12.50-17.17, and 8.8-12.64 espec i ely. F om
Augus 2020 o Feb ua y 2021, he e was e y small GSI alues a ied om 1.78-
4.03, 0.23-4.27, 1.88-4.42, 0.34-0.82, 0.08-0.74, 0.37-0.82, and 0.37-0.82 espec i ely.
Only in Ma ch he GSI alue was medium.
37
Figu e 13 F equency occu ence o ma u i y s ages o oocy es
F equency o spawning and measu emen o egg diame e
Fo he measu emen o egg diame e abou 100 eggs we e aken andomly om
he mixed sample o eggs o ma u e ish species. These we e a anged in se e al
ows on a glass slide and diame e o indi idual o a was aken wi h he help o
s e eomic oscope. The diame e o o a along wha e e axis hey lay pa allel o he
g adua ion o he mic ome e, we e measu ed o ensu e andom na u e o he
eadings and unbiased alues as sugges ed by Cla k (1934). The measu emen s o
egg diame e we e aken in millime e along he longes axis o he egg. F equency
dis ibu ions o egg diame e o o a ies we e anged om 0.4 mm o 0.8 mm in size
and ecundi y we e coun ed as om 0.6 mm o 0.8 mm. The size ange o 0.4 mm
we e no included as ecundi y es ima ion because o hei e y smalle in size
(Figu e 18). The abo e ac s concluded ha Pun ius sopho e was a single spawne ,
i.e., synch onous species and i spawned once in a spawning season.
38
Figu e 14 Size equency dis ibu ion o oocy es o P. sopho e
Minimum leng h a ma u i y
Female o a ies classi ied o p ema u e s ages we e used o de e mine he minimum
leng h a ma u i y. Female ha ing p ema u e oocy e was in s anda d leng h o 56
mm and i s gonadosoma ic index was 7.48. The ela ionship be ween
gonadosoma ic index (GSI) and s anda d leng h (SL) o emale ha ing ma u e
gonad has been demons a ed in Figu e 15.
Figu e 15 Rela ionship be ween gonadosoma ic index (GSI) and s anda d leng h o
emale ha ing ma u e gonad. Yellow do indica es he GSI o younges
adul emale ha ing 56 mm SL in his s udy
39
Fecundi y
A e es ima ing he b eeding season, depending on he egg diame e 133 emale
specimens we e aken o ecundi y es ima ion. The ange o ela i e ecundi y was
om 450 o 4352 pe gm o ma u e emale in e ms o s anda d leng h om 56 mm
o 92 mm espec i ely (Table 6).
Table 6 Mon hly ecundi y o P. sopho e
Mon hs
Mean
ecundi y
Min. o
ecundi y
Max. o
ecundi y
No o Fish
examined
F-
alue
LSD
(5%)
Ma - 21
1713.129c
520
2315
22
65.904
386.76
Ap - 21
1827.909c
720
2781
11
May-21
2284.833b
1440
4005
12
Jun-21
3358.654a
1494
4352
26
Jul-20
1546.35c
520
2621
20
Aug-20
1262d
998
1478
22
Sep-20
1092.85d
816
1500
20
LSD: Leas signi ican di e ence
In a column igu e wi h same le e do no di e signi ican ly whe eas igu es wi h dissimila le e
di e signi ican ly (as pe DMRT).
Rela ionship be ween ecundi y and s anda d leng h
The sca e diag am ob ained om he ecundi y and s anda d leng h showed a
non-linea cubic ela ionship (Figu e 16). In he de e mina ion o his ela ion,
s anda d leng h was aken as independen a iable, while ecundi y as dependen
a iable. S anda d leng h and ecundi y yielded cubic ela ionship, he equa ion
was F= 0.0232SL2.6877 ( 2=0.8683) and he yielded equa ion indica ed ha ecundi y
was highly co ela ed wi h he s anda d leng h o ish.
40
Figu e 16 The ela ionship be ween ecundi y and s anda d leng h o P. sopho e
du ing spawning season
Rela ion be ween ecundi y and body weigh
The sca e diag ams ob ained om he ecundi y and body weigh showed a linea
ela ionship (Figu e 17). In he de e mina ion o his ela ion, body weigh was
aken as independen a ian , while ecundi y as dependen a ian . The
ela ionship be ween ecundi y and body weigh was in he o m o s aigh line,
and he es ima ed equa ion was F = 213.44BW + 125.24 ( 2 = 0.892) and i was
concluded ha ecundi y was highly co ela ed wi h he body weigh o ish.
Figu e 18 shows he equency dis ibu ion o egg diame e s o he expe imen al
uni s and he diame e o egg om whe e ecundi y coun ing was s a ed.
y = 0.0232x2.6877
R² = 0.8683
0
1000
2000
3000
4000
5000
6000
020 40 60 80 100 120
No o Eggs
SL (mm)
41
Figu e 17 The ela ionship be ween ecundi y and body weigh o P. sopho e du ing
spawning season
Figu e 18 Size equency dis ibu ion o oocy es o P. sopho e. Fecundi y was
coun ed wi h he eggs igh o he a ow
y = 212.76x - 110.14
R² = 0.8891
0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
0 5 10 15 20 25
No o Eggs
BW (g)
42
DISCUSSION
The knowledge on ep oduc i e biology o ish is essen ial o e alua ing he
comme cial po en iali ies o i s s ock, li e his o y, cul u e p ac ice and managemen
o i s ishe y. In o de o achie e success in ish cul u e i is impo an o assess he
yea ly b eeding cycle o cul u able ishes. Some o hem b eed once a yea while
some a egula in e als h oughou he yea . In o ma ion o gonadal de elopmen
and he spawning season o a species is also impo an o i s managemen .
The aim o he s udy o ep oduc i e biology o Pool ba b, P. sopho e was o iden i y
he spawning seasons, de e mine he minimum leng h a ma u i y, equency o
spawning, ma u a ion s ages o oocy es, equency dis ibu ion o eggs and
ecundi y o he species. The e o e, he in es iga ion was ca ied ou om July 2020
o June 2021 in a na u al ese oi o he Rajdhala beel, Pu badhala, Ne okona,
Bangladesh.
The gonadosoma ic index (GSI), which is indica i e o he b eeding season o he
ish, had been calcula ed om Ma ch o June. The e was a sudden ise in he alues
in Ma ch and g adually inc eased ill June. The highes gonadosoma ic index o P.
sopho e was in June and he lowes was in Decembe . This indica es ha P. sopho e
may b eed in Ma ch o June. These da a sugges ha one spawning season migh
occu om Ma ch o July. These indings ag ee wi h he indings o Mi a e al.
(2005) and Hasan e al. (2018).
Alam e al. (2014) ound he b eeding season o pool ba b om May o Augus while
Bi hy e al. (2013) epo ed he mon hs om June o Augus . Bi hy e al. (2013) also
de e mined July as a b eeding mon h o P. sopho e. Mo eo e , Mi a e al. (2005)
obse ed ha he b eeding season o his ish ex ended Feb ua y o Augus and
May-June as spawning mon hs.
Hasan e al. (2018) ound ha he b eeding season uns om Ma ch o July, peaking
in Ap il and May in Gazipu Bangladesh. The same s udy also iden i ied May o
July as he b eeding season in Jesso e, Bangladesh. Due o he ac ha Jesso e is a
43
bao a ea wi h nume ous bao s and beels, he cu en s udy loca ion Rajdhala beel
has simila hyd og aphic cha ac e is ics, which could be one explana ion o he
pa allels be ween he wo s udies.
Peaks o he GSI index alue in June migh be due o comple ion o ma u i y and
subsequen s eep all in he index alue clea ly indica ed al e na i ely he
spawning and spen condi ion o ish. The gonadosoma ic index inc eased wi h he
ma u a ion o ish, being maximum du ing he pe iod o peak ma u i y and
declined ab up ly he ea e , when ish became spen (LeC en, 1951). T easu e and
Holiday (1981) in s udies wi h Pe ca lu in ilis, Piska e al.（1991) wi h Salmos ona
phulo s a ed ha GSI was use ul o es ablishing spawning pe iod. The mon hly
changes in GSI e lec he o a ian ac i i y o ish and i mus be no iced ha GSI is
a eliable ool o de e mine peak spawning season (Vladimi , 2000). Howe e , he
p esen esul s we e ully ag eed wi h ha o Mi a e al. (2005). Addi ionally, he
occu ence o spawning o a ies examined by ex e nal cha ac e is ics began o
appea in Ma ch and con inued up o July. Pe cen occu ence o o a ies s a ed o
inc ease in Ma ch and peaked in June. I appea ed in Ma ch o some ex en and
g adually peaked in June and s eadily declined in Augus . A e ha i was no
ound in Sep embe o Feb ua y.
In he p esen s udy, mon hly changes o gonadosoma ic index o P. sopho e
e ealed ha mean GSI inc eased once in a yea in June sugges ed one peaks o GSI.
Va ious de elopmen al s ages o o a ies we e classi ied conside ing hei ex e nal
ea u es and he mac oscopic iews o eggs. The s ages we e imma u e, de eloping,
ma u ing and spawning. Ex e nal mo phology and mac oscopic obse a ion o
emale gonads showed ha he spawning season o pool ba b was Ma ch o July.
This inding is simila o indings o Mi a e al. (2005); Bi hy e al. (2013) and Alam
e al. (2014) who ound one peak b eeding season o P. sopho e in di e en egions.
Alam e al. (2014) ound he season o be May o Augus in Bangladesh while Bi hy
e al. (2013) epo ed he season o be June o Augus wi h July as peak mon h in
Bangladesh. These esul s a e simila o he inding o his s udy, whe e Ma ch o
July is he b eeding pe iod o Pool ba b in Rajdhala beel in Ne akona, Bangladesh.
44
His ology is a powe ul ool o biological assessmen . In his s udy, oocy es
ma u i y s ages we e classi ied in o i e s ages as ea ly pe inucleolus s age, yolk
esicle s age, p ima y yolk s age, mig a o y nucleus s age and p ema u e s age.
The p ema u e s age was obse ed as he mos ad anced s age in he s udy. Mos
ad anced ma u e s ages indica ed ha p obabili y o spawning migh be occu ed
wi hin sho ime. O he ad anced ma u i y s ages we e no ound su ely because
he sampling ime was du ing he mo ning, when o a ies migh no supposed o
be eady o o ula ion and spawn ye . I is belie ed ha i samples a e aken in la e
a e noon and e ening du ing he spawning season, mo e ad anced ma u i y
s ages may appea (Vladimi , 2000). Howe e , emales classi ied in o p ema u e
s age we e supposed o eady o capable o spawning o nea o spawn. The mos
ad anced p ema u e s age oocy e i.e., p ema u e oocy e was p esen om Ma ch
o June. The e was no p ema u e oocy e obse ed in he mon h o Sep embe . These
esul s indica ed one spawning season o P. sopho e p ecisely las ed om Ma ch o
June. O a y o P. sopho e was a synch onous ype ha con ained almos simila
oocy e ma u a ion s ages.
This ype o oocy e ma u i y was by a he mos common s a egy among eleos
(Wallace and Selmanm, 1981; Lee e al., 2005) s udied wi h Leiogna hus equulus and
ound eigh ma u i y s ages o oocy es as ch oma in nucleolus, pe inucleolus, yolk
esicle, p ima y yolk, seconda y yolk, e ia y yolk, mig a o y nucleus and ipe
s age by his ological examina ion o o a ies.
Spawning equency may be de e mined on he basis o he occu ence o p esence
o pos o ula o y ollicle, hyd a ed eggs (De Ma ini and Foun ain, 1981; Hun e
and Macewicz, 1985) and mode o equency dis ibu ion o egg diame e (She y
e al., 1996). In ac , hyd a ed eggs and pos o ula o y ollicles we e no obse ed in
he o a ies h oughou he s udy pe iod.
The p esence o almos same oocy e ma u i y s ages in he his ological sec ion o
ma u ed emale o a ies we e obse ed du ing he s udy pe iod which indica ed
ha emale P. sopho e we e single spawne (i.e., may spawn only once du ing a
single spawning season). While in case o mul iple o se ial spawne , ish may
45
spawn mo e han once du ing a single spawning season. Pos o ula o y ollicles o
hyd a ed eggs a e he indica ions o a se ial spawne (Geo ge, 1996). Bu no
pos o ula o y ollicles o hyd a ed eggs we e ound in he cu en s udy. Hence,
his in o ma ion e ealed ha he expe imen al ish spawned once in a spawning
season.
The s udy ound ha he s anda d leng h o he younges emale ha bo e ma u e
eggs was 56 mm, and i s gonadosoma ic index was 7.48. Minimum size o ma u i y
is no an independen c i e ion, bu is one ha closely associa ed wi h he o he
ea u es o g ow h, ood supply, e c. o a pa icula s ock o popula ion. In gene al,
minimum size o ma u i y is also ela ed o he longe i y and he a e o g ow h.
When he sexes di e in longe i y ha wi h he lowe longe i y ends o ha e a
highe a e o g ow h and minimum size o ma u i y and ice e sa. In he wes
coas spa he g ow h a e and longe i y o he sexes ha e been shown o be almos
iden ical (De-Sil a, 1973) and hence, as expec ed, bo h sexes ha e he same
minimum size and age a ma u a ion. This inding is simila o he indings o
Hossain e al. (2012) and Mi a e al. (2005).
The ange o ela i e ecundi y was om 540 o 4352 pe gm o ma u e emale which
main ained s anda d leng h om 56 mm o 92 mm. I was obse ed ha emale
specimens belonging o he same size g oup had di e en numbe o eggs in hei
o a ies. Lagle e al. (1967) epo ed ha he numbe o eggs p oduced by an
indi idual emale was dependen on a ious ac o s like size, age, condi ion and
ype o species o he ish. I was also obse ed in some cases ha he ecundi y o
some la ge ishes was much less han ha o some smalle ishes. This ype o
a ia ion was also epo ed by di e en wo ke s (Doha and Hye, 1970; Ka im and
Hossain, 1972). The ela ionship be ween he ecundi y and s anda d leng h o P.
sopho e ound o be nonlinea cubic ela ion and was exp essed as F= 0.0232SL2.6877
( 2=0.8683) du ing spawning season (i.e., om Ma ch o July). The equa ion yielded
2=0.8683 indica ed ha ecundi y was highly co ela ed wi h he s anda d leng h
o ish. Simila ela ionship o P. sopho e was ound by Ta eque e al. (2008). Some
o he s udies ound linea ela ionship be ween ecundi y and leng h o P. sopho e
(Bi hy e al., 2013; S i as a a, 2003; Kan e al., 2016).
46
The ela ionship be ween he ecundi y and body weigh o P. sopho e was linea
and i was exp essed as F = 213.44BW+125.24 ( 2 = 0.892) du ing spawning season.
F om he linea alue 2=0.892, i was concluded ha ecundi y was highly
co ela ed wi h he body weigh o ish which is ela ed o he indings o S i as a a
(2003); Ta eque e al. (2008); Bi hy e al. (2013) and Kan e al. (2016).
The indings o his s udy can be said eliable as all he indings we e mo e o less
ma ches wi h he ela ed li e a u es and indings. Mos o he dissimila i ies
occu ed due o a ia ion o egional and en i onmen al ac o s.
53
Ma ina A 2006: Rep oduc i e biology o Pool ba b Pun ius sopho e (Hamil on, 1822)
o a pe ennial wa e body in Bangladesh. M. S. Thesis, Depa men o
Fishe ies Managemen , Bangladesh Ag icul u al Uni e si y Mymensingh.
Mic oso Co po a ion 2020: Mic oso Excel 2019 [Compu e So wa e], Redmond,
Washing on, USA. h ps://o ice.mic oso .com/excel.
Mi hu M 2012: An in es iga ion o he ep oduc i e physiology and a i icial
p opaga ion o endange ed mud eel Monop e us cuchia. M.S. Thesis,
Depa men o Fishe ies Managemen , Bangladesh Ag icul u al Uni e si y,
Mymensingh.
Mi a K, Su esh VR, Vinci GK, Naska B 2005: Leng h weigh ela ion, ep oduc i e
cha ac e s and condi ion o Pun ius sopho e (Hamil on) om a loodplain
we land in Wes Bengal. Jou nal Inland Fishe ies Socie y o India 37(May) 16–22.
Mollah MFA 2005: Annual inal epo on Domes ica ion and Induc ion o B eeding
o Ri e ine Ca ish Ri a i a (Hamil on) submi ed o he Uni e si y G an s
Commission o Bangladesh. 18 pp.
Mookhe jee HK, Basu SP 1946: Li e his o y o Amblypha yngodon mola (Ham.)-a
delica e ood ish o Bengal. Science & Cul u e Calcu a 12(1) 54-56.
Mo in MA 2011: His ological s udy o game ogenesis in endange ed Pabo ca ish
(Ompok pabo) om he Sylhe basin in he no h-eas Bangladesh. M. S. Thesis,
Depa men o Fishe ies Managemen , Bangladesh Ag icul u al Uni e si y,
Mymensingh, Bangladesh.
Mus a a G 1991: Composi e cul u e and biology o some indigenous ishes o
Bangladesh. PhD Thesis, Facul y o Biological Science, Dhaka Uni e si y,
Dhaka.
Mus a a G, Islam KR, Ali S, Alam AKMA 1980: Food, eeding habi and ecundi y
o eshwa e pe ch Nandas nandas (Hamil on), meni ish [Bangladesh].
Bangladesh Jou nal o Ag icul u e 8(1) 59-73.
Pa ween S, Begum N, Rahman MH, Hossain MA 1993: On b eeding pe iodici y o
Esomus dan icus (Hamil on). Rajshahi Uni e si y Jou nal o Zoology 12 31-34.
54
Pe T 1999: Coldwa e ish and ishe ies in Bhu an. Food and Ag icul u e
O ganiza ion Fishe ies Technical Pape 385 6–12.
Piska RS, Wagh ay S, P asad MR 1991: Rep oduc i e biology o sil e ish,
Salmos oma phulo (Ham.) om lowe Manai ese oi , Ka imnaga , Andh a
P adesh. Indian Jou nal o Fishe ies 38(3) 157-164.
P asad S, Sinha DP, Chanchal AK, Pandey N 1979: S udies on some aspec s o he
biology o M. aculea us. Ancien Ins i u o de Ciencias del Ma y Limnologia,
Uni e si y o Na ional Au onomous Mexico 6(2) 59-66.
Qayyum A, Qusim SZ 1964: S udies on he biology o some eshwa e ishes. II:
B a bus s igma: (Cu : g. al.). Jou nal o he Bombay Na u al His o y Socie y 61(2)
330-347.
R Co e Team 2021: R: A Language and En i onmen o S a is ical Compu ing
[Compu e P og amming Language], Vienna, Aus ia. h ps://www. -
p ojec .o g/.
Rahman A 2005: F eshwa e ishes o Bangladesh, Zoological. Zoological Socie y o
Bangladesh. 2nd ed. Vol. 18. Dhaka: Zoological Socie y o Bangladesh.
Rahman MA, Haque MM 2008: Beel ishe y and li elihood o he local communi y
in Rajdhala, Ne akona, Bangladesh. Bangladesh Jou nal o Fishe ies Resea ch
12(1) 95–108.
Ras ogi RK, Saxena PK 1968: Annual changes in he o a ian ac i i y o he ca ish
Mys as enga a (Ham). Japanese Jou nal o Ich hyology 15(1) 22-25.
RS udio Team 2022: RS udio: In eg a ed de elopmen en i onmen o R [Compu e
So wa e], Bos on, Massachuse s. h p://www. s udio.com/.
Samad MA, Asaduzzaman M, Galib SM, Kamal MM, Haque MR 2010: A ailabili y
and consume p e e ence o small indigenous species (SIS) o he i e Padma
a Rajshahi, Bangladesh. In e na ional Jou nal o Bio esea ch 1(5) 27-31.
San os RS, Hawkins S, Mo eino LR, Al es M, Isid o EJ 1995: Case s udies and
e iews. Ma ine esea ch, esou ces and conse a ion in he A20. Aqua ic
Conse a ion: Ma ine F eshwa e Ecosys ems 4 311-354.
55
Sha i M, Quddus MMA 1974a: Bionomics o he common Pun i, Pun ius s igma
(Cu . & Val.) o Bangladesh. Bangladesh Jou nal o Zoology 2(1) 77-82.
Sha i M, Quddus MMA 1974b: The ecundi y o he common pun i, Pun ius s igma
(Cu ie & Alenciennes) (Cyp inidae: Cyp ini o mes). Bangladesh Jou nal o
Zoology 2(2) 133-145.
She y C, Heileman M, Nelson ME 1996: Spawning equency and spawning
po en ial o he whi e mou h C ocke Mic opogonias u nie i in T inidad, Wes
Indies. Bulle in Ma ine Science 58(1) 156-164.
Sinha M 1975: Obse a ion on he biology o Pun ius sa ana (Ham.) o Loni
Rese oi (Madhya P adesh). Jou nal o Inland Fishe ies Socie y, India 7 49-57.
Sobhana B, Nai NB 1974: Obse a ion on he ma u a ion and spawning o Pun ius
sa ana (Valeniennes). Indian Jou nal o Fishe ies 21(2) 357-363.
S i as a a R 2003: Some Aspec s o Fishe y Biology o Pun ius sopho e (Ham.).
Uni e si y o Allahabad.
Talwa PK, and Jhing an AG 1991a: Inland Fishes o India and Adjacen Coun ies.
Taylo & F ancis.
Talwa PK, and Jhing an AG 1991b: Inland Fishes o India and Adjacen Coun ies.
Ox o d and IBH Publishing Co. P . L d. New Delhi, Bombay and Calcu a.
pp. 1158.
Ta eque AMHB, Biswas B, Hossain SM, Rahman MM, Rahman MM 2008: Some
aspec s o biology o Pun ius sopho e (Hamil on) collec ed om he Mou i
Ri e , Khulna, Bangladesh. Bangladesh Resea ch Publica ions Jou nal 2(1) 68–74.
Thils ed SH, Roos N, Hasan N 1997: The ole o small indigenous ish species in
ood and nu i ion secu i y in Bangladesh. NAGA 20 (3/4) 82–84.
Thompson P, Roos N, Sul ana P, Thils ed SH 2002: Changing signi icance o inland
ishe ies o li elihoods and nu i ion. Bangladesh. Jou nal o C op P oduc ion 6
249-318.
56
T easu e JW, Holliday FGT 1981: Some aspec s o he ep oduc i e biology o
pe ch Pe ca lu ia ilis L, a his ological desc ip ion o he ep oduc i e cycle.
Jou nal o Fishe ies Biology 18 359–376.
Vladimi PG 2000: Age, g ow h and ep oduc ion o yellow belly Th ead in B eam,
Nemip e us ba hybius in Kagoshima Bay, Sou he n Japan. PhD Thesis,
Kagoshima Uni e si y, Japan.
Wallace RA and Selman K 1981: Cellula and dynamic aspec s o oocy e g ow h in
eleos s. Ame ican Zoologis 21 (2) 325–43.
WHO 2011: Wo ld Heal h O ganiza ion. Vi amin and mine al nu i ion
in o ma ion sys em (VMIS). Mic onu ien da abase.
Wickham H 2016: Ggplo 2: Elegan g aphics o da a analysis. Sp inge -Ve lag
New Yo k. h ps://ggplo 2. idy e se.o g.
Ziki TB 2006: Rep oduc i e biology o Mys uas i a us o a pe ennial wa e body in
Bangladesh, M.S. Thesis, Depa men o Fishe ies Managemen , Bangladesh
Ag icul u al Uni e si y, Mymensingh.
57
APPENDICES
Appendix- 1 Analysis o Va iance (One-way ANOVA) o mon hly s anda d leng h
(SL), body weigh (BW), gonadosoma ic index and ecundi y
Sum o Squa es
d
Mean Squa e
F
Sig.
SL(cm)
Be ween G oups
184.153
11
16.741
42.454
<0.001
Wi hin G oups
91.882
233
.394
To al
276.035
244
BW (g)
Be ween G oups
2377.303
11
216.118
48.268
<0.001
Wi hin G oups
1043.257
233
4.477
To al
3420.560
244
GSI
Sum o Squa es
d
Mean Squa e
F
Sig.
Be ween G oups
5635.013
11
512.274
236.455
<0.001
Wi hin G oups
418.130
193
2.166
To al
6053.143
204
Fecundi y
Sum o Squa es
d
Mean Squa e
F
Sig.
Be ween G oups
90681264.315
6
15113544.052
65.904
<0.001
Wi hin G oups
28895369.363
126
229328.328
To al
119576633.678
132
58
Appendix- 2 Sou ce code (R) o da a analysis
DATA ANALYSIS FOR REPRODUCTIVE BIOLOGY OF
PUNTI (P. SOPHORE) IN RAJHDHALA RESERVOIR,
NETROKONA
Md. Ash aq Sada
Loading Da a om Raw da a
lib a y( ead )
da a_pun i <- ead_cs ("da a_pun i.cs ",
col_ ypes = cols(Mon h_NO = col_ ac o (le els = c("1",
"2", "3", "4", "5", "6", "7", "8",
"9", "10", "11", "12")), Sex = col_skip(), Mon h = col_ ac o (le
els = c("Janua y", "Feb ua y", "Ma ch", "Ap il", "May", "June","July",
"Augus ","Sep embe ","Oc obe ","No embe ", "Decembe "))))
# Loading mon hly Gonadal S age F equency Da a
gonadF eq <- ead_cs ("F equncy o Gonad S ages.cs ",
col_ ypes = cols(Mon h = col_ ac o (le els = c("Janua y","Feb ua y",
"Ma ch", "Ap il", "May","June", "July", "Augus ", "Sep embe ","Oc obe "
, "No embe ", "Decembe ")),S ages = col_ ac o (le els = c("Res ing",
"De eloping", "Ripe", "Spawning",
"Spen ")), Pe cen = col_in ege ()))
## Wa ning: One o mo e pa sing issues, see `p oblems()` o de ails
# Loading mon hly his ology F equency Da a
his F eq <- ead_cs ("his F eq.cs ",
col_ ypes = cols(mon h = col_ ac o (le els = c("Janua y","Feb ua y",
"Ma ch", "Ap il", "May","June", "July", "Augus ", "Sep embe ","Oc obe "
, "No embe ", "Decembe ")),s ages = col_ ac o (le els = c("EP",
"YV", "PY", "MN",
"PM")), pe cen = col_in ege ()))
Dis ibu ion o To al leng h along mon hs
lib a y(ggplo 2)
ggplo (da a=da a_pun i, aes(SL_mm)) + geom_his og am(bins=5)+ ace _w ap(
da a_pun i$Mon h)+ylab("F equency")+xlab("S anda d Leng h (mm)")
59
Dis ibu ion o Body Weigh along mon hs
lib a y(ggplo 2)
ggplo (da a=da a_pun i, aes(BW)) + geom_his og am(bins = 5)+ ace _w ap(d
a a_pun i$Mon h)+ylab("F equency")+xlab("Body Weigh (g)")
Dis ibu ion o GSI along mon hs
lib a y(ggplo 2)
ggplo (da a=da a_pun i, aes(GSI)) + geom_his og am(bins=6)+ ace _w ap(da
a_pun i$Mon h)+ylab("F equency")+xlab("Gonadosoma ic Index")
## Wa ning: Remo ed 40 ows con aining non- ini e alues (s a _bin).
60
lib a y(ggplo 2)
ggplo (da a=da a_pun i, aes(Diame e )) + geom_his og am(bins = 7, bounda
y = 0)+ylab("F equency")+xlab("Egg Diame e ")
## Wa ning: Remo ed 118 ows con aining non- ini e alues (s a _bin).
Mon hly Changes in Gonadosoma ic index
F equency o Gonadal De elopmen
ggplo (gonadF eq,aes(x=Mon h, y = Pe cen , ill= S ages))+geom_col()+gui
des( ill=guide_legend( e e se=FALSE))+
61
heme(axis. ex .x = elemen _ ex (angle = 45, hjus =1))+labs(x ="Mon hs
", y = "F equency Pe cen (%)")
## Wa ning: Remo ed 16 ows con aining missing alues (posi ion_s ack).
F equency o His ology De elopmen
ggplo (his F eq,aes(x=mon h, y = pe cen , ill= s ages))+geom_col()+guid
es( ill=guide_legend( e e se=TRUE))+
heme(axis. ex .x = elemen _ ex (angle = 45, hjus =1))+labs(x ="Mon hs
", y = "F equency Pe cen (%)")
## Wa ning: Remo ed 27 ows con aining missing alues (posi ion_s ack).
62
Models
da a_pun i%>%
il e (!is.na(Fecundi y)) -> d
#
sl_model <- lm(log(d $Fecundi y) ~ log(d $SL_mm))
summa y(sl_model)
##
## Call:
## lm( o mula = log(d $Fecundi y) ~ log(d $SL_mm))
##
## Residuals:
## Min 1Q Median 3Q Max
## -0.78290 -0.13309 0.00608 0.14184 0.51336
##
## Coe icien s:
## Es ima e S d. E o alue P (>| |)
## (In e cep ) -3.8297 0.4827 -7.934 8.29e-13 ***
## log(d $SL_mm) 2.6877 0.1153 23.318 < 2e-16 ***
## ---
## Signi . codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
##
## Residual s anda d e o : 0.2228 on 131 deg ees o eedom
## Mul iple R-squa ed: 0.8059, Adjus ed R-squa ed: 0.8044
## F-s a is ic: 543.8 on 1 and 131 DF, p- alue: < 2.2e-16
coe (sl_model)
## (In e cep ) log(d $SL_mm)
## -3.829672 2.687672
# The o e all F- alue o he model is 511.2 and he co esponding p- alu
e is ex emely small (< 2.2e-16), which indica es ha he model as a wh
ole is use ul.
#
# Using he coe icien s om he ou pu able, we can see ha he i
ed powe eg ession equa ion is:
#
# ln(F) = -3.7614 + 2.6718*ln(SL)
#
# Applying exp o bo h sides, we can ew i e he equa ion as:
#
# F = exp (-3.7614 + 2.6718*ln(SL))
# calcula ing exp(2.6718)
exp (-3.7614)
## [1] 0.02325117
# i we plo he alue on he equa ion
# We ge he inal equa ion is F = 0.02325 SL^2.6877
# We can use his equa ion o p edic he esponse a iable, y, based on
he alue o he p edic o a iable, x.
# plo ing he da a
