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Page 1: Testes morphology and reproductive aspects of male Brazilian codling (Urophycis brasiliensis Kaup 1858)

J[ Appl[ Ichthyol[ 05 "1999#\ 023Ð024 Received] December 0\ 0887Þ 1999 Blackwell Wissenschafts!Verlag\ Berlin Accepted] February 5\ 0888ISSN 9064Ð7548

This is a companion paper to Acun½a\ A[^ Viana\ F[^ Vizziano\ D[^ Danulat\ E[] Reproductive cycle of female Brazilian codling\Urophycis brasiliensis "Kaup 0747#\ caught o} the Uruguayan coast[ Journal of Applied Ichthyolo`y\ 05"1#\ pp 37Ð44[

Short Communication

Testes morphology and reproductive aspects of male Brazilian codling "Urophycisbrasiliensis Kaup 0747#

By F[ Viana\ A[ Acun½a\ N[ Berois and E[ Danulat

Seccio�n Oceano`ra_a\ Facultad de Ciencias\ I`ua� 3114\ 00399 Montevideo\ Uru`uay

Summary

The very _rst data on male {bro�tola| Urophycis brasiliensis"Phycidae\ Gadiformes# are presented here[ Apart from thedescription of the macroscopic and microscopic morphology ofthe testes\ preliminary results are given with respect to repro!ductive aspects of the males caught o} the Uruguayan coast[

In Uruguay\ the gadiforms are represented by two species ofcommercial interest] the hake Merluccius hubbsi being theprincipal _shing resource\ and Brazilian codling Urophycisbrasiliensis locally called {bro�tola|\ one of the most importantcoastal resources of the artisanal _sheries "Anon[ 0880#[ Althoughthe latter species is common in coastal waters of the Atlanticbetween 12> and 39> S\ little information is available[ Between0882 and 0885\ a comprehensive 2!year study dedicated to aspectsof the biology and _sheries of U[ brasiliensis in Uruguayan waterswas carried out[ A manuscript on reproductive aspects of thefemales has been submitted for publication "Acun½a et al[ 1999#[ Inthe present paper\ _rst results on the gonadal morphology of themales are given[ Vladikov "0861# compared the testes of di}erentgadids\ including another species of the genus\ Urophycis chuss[However\ to date no related information has been published onU[ brasiliensis\ likely also due to the fact that males are much lessfrequent than females in nearshore captures[

Samples "N � 47# of shallow captures "³19 m# of {bro�tola|were obtained from artisanal _shermen in the two most impor!tant _shing ports in Uruguay] Piria�polis "23> S 44> W# and LaPaloma "23> S 43> W# "Acun½a et al[ 1999#[ Additional samples"N � 10# of deeper captures "up to 42 m# were obtained onspring and summer cruises of the research vessel {Aldebara�n|"INAPE^ National Fisheries Institute#[

In the _eld\ total length and weight were recorded to thenearest cm and g\ respectively "Table 0#[ Fish size ranged from12Ð59 cm and 002Ð1399 g\ respectively[ Following dissection\the _sh were sexed\ and in most cases "N � 58# testes wereweighed to the nearest 9[90 g[ Gonads were extracted and _xedin 09) bu}ered formalin until the histological analysis[ Inthe laboratory\ ten testes were cut at di}erent levels "cephalic\medium and caudal# to determine possible longitudinal di}er!ences in the spermatogenesis[ Twenty samples were analyzedhistologically to identify testicular structures and to diagnosethe gonad maturity stage[ Each piece was dehydrated\ embeddedin para.n\ cut to 6mm thickness and _nally stained with Mayer|shaematoxilin and eosin "Ganter and Jolle�s 0869#[ The gonado!

U[S[ Copyright Clearance Center Code Statement] 9064Ð7548:1999:0592Ð9023,04[99:9

somatic index "GSI# was calculated and compared in bothshallow and deeper capture areas in spring and summer[

Macroscopically\ the male gonad of U[ brasiliensis "Fig[ 0# iseasily distinguishable from the ovaries\ allowing a rapid andunmistakable sex identi_cation in the _eld[ Two testes of dissimilarlength are found below the swimbladder[ They can be seen as twowhitish ribbons presenting a smooth surface and several irregularlobes\ similar to U[ chuss testes "Vladykov 0861#[ Their macro!scopic structure corresponds to type IIIa of the classi_cation pre!sented by Vladykov "0861#[ The lobes are larger in the cephalicportion than in the caudal portion\ and fused to the vas deferensthat longitudinally crosses both testes[ In the caudal region\ theyare fused and open to the urogenital ori_ce[

Histologically\ the {bro�tola| testes correspond to the lobulartype described by Billard "0875# with anastomosing tubules"Fig[ 1#[ All along the testes\ similar spermatogenesis wasobserved[ They can also be de_ned as the unrestricted spermato!gonial type of Grier "0870#\ the most common testes type in _shspecies\ where it is possible to _nd spermatogenesis along theentire length of the tubule[ In the caudal region\ an area isfound without spermatogenetic epithelium but with a greaterconcentration of spermatozoa ready to be evacuated[

Males were signi_cantly less represented in the captures thanwere females "P³ 9[94#\ making up only 2) of the total catch"N � 1499#[ Wenner "0872# and Gallardo!Cabello "0875#showed sex segregation in two other species of the same family"Phycis phycis\ P[ blennoides#[ At the same time\ Eklund andTargett "0889# observed di}erent sex proportions in capturesof U[ re`ia "spotted hake# and U[ chuss "red hake#[ However\this e}ect was explained by selectivity of the capturing gear[

Mean total length of males showed signi_cant di}erences"P ³ 9[94# between shallow "23[7 cm# and deeper "18[2 cm# cap!tures[ The segregation by size might be explained by intrae!speci_c competition "Sedberry and Musick 0867# which\ incombination with the selectivity of the _sheries\ would result ina higher proportion of females in the samples[

Captures revealed a signi_cant size di}erence between males"this paper# and females "Acun½a et al[ 1999#\ reaching meanlengths of 22[5 cm and 33[9 cm\ respectively[ The size of allindividuals exceeds the one proposed as the mean size ofmaturity "12 cm# for U[ brasiliensis males caught o} SouthernBrazil "M[ Haimovici\ pers[ comm[#[

Due to the scarce representation of the males in the samples\it was not possible to study the spatial and temporal variation

Page 2: Testes morphology and reproductive aspects of male Brazilian codling (Urophycis brasiliensis Kaup 1858)

Testes morphology and reproductive aspects of male Brazilian codling 024

Table 0Total length "cm# and weight "g# of male U[ brasiliensis captured by theartisanal _shery and from RV {Aldebara�n|[ Mean values 2 standarddeviation are presented

Length "cm# Weight "g#Sample origin N Mean SD Mean N SD

Artisanal _shery 47 23[2 3[9 47 245 039RV {Aldebara�n| 10 18[3 2[1 10 140 001

Fig[ 0[ Macroscopic view of the U[ brasiliensis testes\ corresponding toan individual of 20 cm[ Note the dissimilar length and irregular lobesin the two testes[ Numbers indicate centimeters

of testicular maturation[ At any rate\ mainly stages of mid! andlate recrudescence\ partially spent and one post!spawn wereidenti_ed[ At a mean length of 21[5 cm\ signs of testes recrud!escence "Table 1# were observed[

Testicular GSI ranged between 9[93 and 1[79[ In deeper cap!tures\ mean GSI was signi_cantly higher\ indicating a greatermaturation activity during spring and summer[ This may sug!gest that reproductive events of U[ brasiliensis take place outsidethe artisanal _shing areas\ as proposed for females of the speciesby Vizziano et al[ "0882# and Acun½a et al[ "1999#[

Acknowledgements

Funding was provided by the Comisio�n Sectorial de Investi!gacio�n Cient(�_ca "CSIC# and PEDECIBA!CONICYT ofUruguay[ Also\ the authors wish to thank the _shermen AlfredoHargain\ and Pelusa and Atilio Batista and personnel of theInstituto Nacional de Pesca "INAPE# for making available thestudy material[

References

Acun½a\ A[^ Viana\ F[^ Vizziano\ D[^ Danulat\ E[\ "1999#] Reproductivecycle of female Brazilian codling\ Urophycis brasiliensis "Kaup

Fig[ 1[ Histological section of U[ brasiliensis testes[ Z � spermatozoa^CC � spermatocyte cyst^ TC � spermatid cyst^ ZC � spermatozoacyst^ L � lumen of a spermatogenic tubule[ Scale bar � 099 mm

Table 1Mean total length "cm# of U[ brasiliensis males for each maturity stagediagnosed histologically "mid:late recrudescence^ partially spent andpost!spawn# 2 standard deviation

Length "cm#Maturity stages N Mean SD

Mid:late recrudescence 01 21[5 3[4Partially spent 6 28[2 2[3Post!spawn 0 37[6 −

0747#\ caught o} the Uruguayan coast[ J[ Appl[ Ichthyol[ 05\

37Ð44[Anon[\ 0880] Ana�lisis de las pesquer(�as artesanales del Uruguay[ I[

Documento de trabajo al foro[ Centro Cooperativista Uruguayo"CCU# Montevideo\ Uruguay[

Billard\ R[\ 0875] Spermatogenesis and spermatology of some teleost_sh species[ Reprod[ Nutr[ Dev[ 15\ 766Ð819[

Eklund\ A[ M[^ Targett\ T[ E[\ 0889] Reproductive seasonality of _shesinhabiting hard bottom areas in the Middle Atlantic Bight[ Copeia3\ 0079Ð0073[

Gallardo!Cabello\ M[\ 0875] Ana�lisis del crecimiento de la bro�tolaPhycis blennoides "Brunnich 0657# en el Mediterra�neo occidental"Pisces] Gadidae#[ Anales del Instituto de Ciencias del Mar y Limno!log(�a 02\ 096Ð016[

Ganter\ P[^ Jolle�s\ G[\ 0869] Histochimie normale et pathologique[ Eds]Gauthier!Villars\ Paris\ Vol[ 1\ pp[ 811Ð0893[

Grier\ H[ J[\ 0870] Cellular organization of the testes and spermato!genesis in _shes[ Amer[ Zoologist 10\ 234Ð246[

Sedberry\ G[ R[^ Musick\ J[ A[\ 0867] Food habits of some demersal_shes of the continental slope and rise o} the mid!Atlantic coast ofthe U[S[A[ Marine Biol[ 33\ 246Ð264[

Vizziano\ D[^ Lo�pez De Leo�n\ E[^ Ares\ L[\ 0882] Contribucio�n alestudio de la biolog(�a reproductiva de la hembra de Urophycisbrasiliensis "bro�tola# "Teleostei] Gadidae#[ Bolet(�n de la SociedadZoolo�gica del Uruguay 7\ 048Ð053[

Vladykov\ V[ D[\ 0861] Morphological di}erences in male gonadsamong nine genera of Gadidae "Pisces#[ J[ Fish[ Res[ Board Can[18\ 0698Ð0605[

Wenner\ C[ A[\ 0872] Biology of the long_n hake\ Phycis chesteri in thewestern North Atlantic Biol[ Oceanography 2\ 30Ð64[

Author|s address] Federico Viana\ Seccio�n Oceanogra_a\ Facultad deCiencias\ Igua� 0314\ 00399 Montevideo\ Uruguay[e!mail] fvianaÝfcien[edu[uy


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