UNIVERSITI PUTRA MALAYSIA

VIRAL DISEASES OF CULTURED PENAEUS SEMISULCATUS DE HAAN WITH EMPHASIS ON CONTROL MEASURES OF

PENAEUS MONODON BACULOVIRUS (MBV) IN THE ISLAMIC REPUBLIC OF IRAN

MOHAMMAD TOKHMAFSHAN

FPV 2001 2

VIRAL DISEASES OF CULTURED PENAEUS SEMISULCA TUS DE HAAN WITH EMPHASIS ON CONTROL MEASURES OF

PENAEUS MONODON BACULOVIRUS (MBV) IN THE ISLAMIC REPUBLIC OF IRAN

MOHAMMAD TOKHMAFSHAN

DOCTOR OF PHILOSOPHY UNIVERSITI PUTRA MALAYSIA

2001

VIRAL DISEASES OF CULTURED PENAEUS SEMSULCATUS DE HAAN WITH EMPHASIS ON CONTROL MEASURES OF PENAEUS MONODON

BACULOVIRUS (MBV) IN THE ISLAMIC REPUBLIC OF I RAN

By

MOHAMMAD TOKHMAFSHAN

Thesis Submitted in Fulfilment of the Requirement for the Degree of Doctor of Philosophy in the Faculty of Veterinary Medicine

Universiti Putra Malaysia

August 2001

Dedicated to

My parent: Abdolreza Tokhmafshan and Setare Ajafen dake

My wife: Kolsoum Golestan i

My daughter's: Sedigheh, Maedah, and Fatemah, My son: Masoud

For thei r Love, Support and Trust

II

Abstract of the thesis submitted to the Senate of the Universiti Putra Malaysia in fulfilment of the requirement for the degree of Doctor of Philosophy

VIRAL DISEASES OF CULTURED PENAEUS SEMISULCATUS DE HAAN WITH EMPHASIS ON CONTROL MEASURES OF PENAEUS MONODON

BACULOVIRUS (MBV) IN THE ISLAMIC REPUBLIC OF I RAN

By

MOHAMMAD TOKHMAFSAN

August 2001

Chairman: Professor Dr. Mohamed Shariff Mohamed Din

Faculty: Faculty of Veterinary Medicine

Shrimp aquaculture in Islamic Republic of Iran has a short history. Farmed

shrimp production grew slowly from 1992 until 2000 when a number of large

farms started to begin production. In 2000, the production was 4,500 MT and

estimated that more than 7,000 MT will be produce by 2001.

The present study was carried out to investigate the status of viral shrimp

diseases and their impact on the shrimp industry in the I. R. Iran. From August

1997 to March 1998, about two thousand samples of cultured Penaeus

semisulcatus postlarvae and subadults were collected from five hatcheries and

20 growout farms distributed in three provinces along the coast of Persian Gulf

and Oman Sea.

iii

bacu lovirus was infective at salinity ranging from 5-40 ppt whereas at pH 3 and

1 2 , M BV was comp letely inactivated . M BV were not affected at pH 5 , 7 , 8 a nd 9 .

Shr imp exposed for 1 0 h r to M BV at d ifferent ch lorine concentrat ion ( 5 , 25, 5 0 .

1 00 and 2 0 0 ppm) showed that M BV was completely inactivated after 1 0 h r of

exposure to 200 ppm . Formalin in concentration rang ing from 0- 1 00 ppm had no

v i rucidal effect on the infectivity of M BV.

v

Abstrak tesis yang dikemukakan kepada senat Universiti Putra Malaysia sebagai memenuhi keperluan untuk Ijazah Doktor Falsafah

PENYAKIT -PENYAKIT VIRUS UDANG TERNAKAN PENAEUS SEMISULCATUS DE HAAN 01 REPUBLIK ISLAM IRAN DENGA N

TUMPUAN TERHADAP CARA-CARA PENGAWALAN BAGI PENAEUS MONODON BACULOVIRUS (MBV)

Oleh

MOHAMMAD TOKHMAFSHAN

Ogos 2001

Pengerusi: Professor Dr. Mohamed Shariff Mohamed Din

Fakulti: Fakulti Perubatan Veterinar

Ternakan udang di Republik Islam Iran mempunyai sejarah yang singkat.

Pengeluaran udang meningkat perlahan daripada tahun 1992, dan mencapai

4,500 MT pada tahun 2000 apabila ladang-Iadang besar mula beroperasi.

Pengeluaran pad a tahun 2001 dijangka mencapai 7,000 MT.

Kajian ini dijalankan untuk menyiasat status penyakit-penyakit virus udang

dan kesannya terhadap industri ternakan udang di Republik Islam Iran.

Daripada Ogos 1997 hingga Mac 1998, lebih kurang 2,000 sampel pasca larva

(PL) dan subdewasa udang Penaeus semisulcatus telah dikumpulkan daripada

lima pusat penetasan dan 20 ladang ternakan yang terletak di tiga daerah di

sepanjang pantai Teluk Persian dan Laut Oman.

vi

Virus sama hepatopankreatlk parvo (HPV) d an virus baculo monodon (MBV)

ada lah keell ( d iameter 20-24nm) dan merupakan v i rus DNA, kerana terdapat

jasad rang kuman Intranukleus dl d a lam hepatopankreas Virus Penaeus

monodon baeu lov l rus ada lah virus D NA berbentuk rod dengan d i ameter 300 ±

25 nm Organ-organ sasarannya la lah hepatopankreas d an eplte l l um usus

tengah D I ladang udang , j umlah kes MBV dan H PV dl ladang u dang mas Ing­

masmg ada lah 50 d an 27% Jumlah kes MBV dl pusat-pusat penetasan ada lah

60% dan H PV 5%

Rentan larva d an pasea l a rva pelbaga l penngkat kepada MBV telah

dlslasat dengan kaedah Inoku lasl mela lU l a i r ke atas zoea , mysis d an PL 1

hmgga 1 2 Kadar jangk ltan (ROI), seventl jangk ltan (SO l ), morta l ltl kumulatlf d an

kadar tumbesaran te lah d ltentu kan Zoea d an mysis masmg-mas lng tldak

menunJukkan Jangk ltan MBV yang boleh d l kesan l ima dan t lga han lepas

Inokulas l Pada penng kat mysis 2 dan PL 1 , MBV boleh d ld lagnosls d ua han

lepas Inoku lasl N i lal ROI d an SOl bagl PL yang leb lh matang ( P L7 h lngga 1 2)

ada lah leb lh tlnggl berbandlng dengan PL yang leb l h muda

Kesan penyahkuman pH, sa l imtl , formal in d an ka ls lum h lpok lond ke atas

MBV telah d ls lasat dengan kaedah Inoku lasl meia lul a i r d engan mendedahkan

P semlsu/catus selama 1 0 jam,dan memanta u perkembangannya selama 1 0

han MBV menunJukkan Infektlvltl terhadap Sa l lnltl 5 h lngga 4 0 ppt d an

membunuh semua udang yang dldedahkan Virus baeu lovlrus monodon bo leh

berjang klt pad a ta hap sal lnltl 5-40ppt tetap i takaktlf pada pH 3 d an 1 2 Virus

VII

Penaeus monodon bacu lovlrus pada udang yang terdedah kepada berbagal

kepa kata n h lpok lond (5 , 25 , 50 , 1 00 dan 200 mg/L) d ldapatl t ld a k a ktlf selepas

1 0 Jam terdedah kepada 200 ppm Forma l i n pad a tahap 0 hlngga 1 00 ppm tlada

kesa n sebagal penyahvlrus atas j angk lta n MBV

VIII

ACKNOWLEDGMENTS

Glory and pra ise be to God , the Omnipotent Omniscient and Omnipresent

for p rovid ing me with the strength and perseverance to complete th is

d issertation despite several obstacles encountered throughout the course of th is

research wh ich at times seemed Insu rmountable

I would l i ke to express my deep sense of g rat itude to my C h ief S upervisor

P rofessor Dr Mohamed Shanff Mohamed Din, for h is Inva l uab le g U i dance and

constructive s uggestions throughout the thesIs research I s incerely appreciate

the Innumerable hours he spent reading the draft and the suggest ions to

provided to Improve the thesIs Gratitude IS also expressed to my co-su perv isors

P rofessor Dr Fatlmah Md Y usoff, and Dr Hassan HJ Mohd Daud for the i r

va l uab le suggestion and k ind assistance th roughout th is study

I would a lso l ike to thank Dr Sohrab Akban for being the co-supervisor

d u nng the penod spent In I ran, and for mak ing necessary a rrangements for me

to spend SIX months In his laboratory at Shlraz University Iran and for his

assistance with electron microscopy

I am g ratefu l to the head and staff of the Persian G u lf F lshenes Research

Centre (PGFRC) for the ir co-operation d u nng the p rocess of cond uct ing the

study

IX

I would l ike to thank Dr Wang Y G for keen Interest I n my theSIS

research HIs suggest ions throug hout the period d U ring my stay In UPM was

extremely usefu l without which the completion of the theSIS wou ld h ave been

delayed I would also l ike to express my tha nks to my col leag ues Deva ra)a

San)oy , N a)lah , Feen le , Abeer, Ag us and those who have he lped me In ma ny

ways The camaraderie w ith these students and friends at UPM IS memorable

I must also thank to Mr Ho 01 Kuan and Ms Azi lah Ja l ll, the staff I n

Electron Microscope U n it, UPM Thei r assistance fac I l itated m y electron­

microscoPIc work successfully

Specia l thanks a re extended to my wife , Kolsoum Golestanl , for he lp ing

and understand ing my absence d U ri ng the complete of theS IS I a lso appreciate

the concern of my d a ug hte rs Sed lg heh , Maeda h , and Fatemah , and son

Masoud , for their sacrifice of need ing attent ion of the i r father

Pra ise be to the Almig hty Al lah Had I t not been H IS Wi ll I would not have

the patience to Withstand the pressure of my research and completion of study

wou ld not have been pOSSib le

x

I certify that an Examination Committee met on 17'h August 2001 to conduct the final examination of Mohammad Tokhmafshan on his Doctor of Philosophy thesis entitled "Viral Diseases of Cultured Penaeus semisu/catus de Haan with Emphasis on Control Measures of Penaeus monodon Baculovirus (MBV) in the Islamic Republic of Iran" in accordance with Universiti Pertanian Malaysia (Higher Degree) Act 1980 and Universiti Pertanian Malaysia (Higher Degree) Regulation 1981. The Committee recommends that the candidate be awarded the relevant degree. Members of the Examination Committee are as follows:

MOHD HAIR BEJO, Ph.D. Associate Professor Faculty of Veterinary Medicine Universiti Putra Malaysia (Chairman)

MOHAMED SHARIFF MOHAMED DIN, Ph.D. Professor J Deputy Dean Faculty of Veterinary Medicine Universiti Putra Malaysia (Member)

FATIMAH MD. YUSOFF, Ph.D. Professor Department of Biology Faculty of Science and Environmental Studies Universiti Putra Malaysia (Member)

HASSAN HJ. MOHD DAUD, Ph.D. Faculty of Veterinary Medicine Universiti Putra Malaysia (Member)

POH-SHING CHANG, Ph.D. Professor Department of Aquaculture National Kaohsiung Institute of Marine Technology Taiwan (Independent Examiner)

AZJS:U'MOHA YIDIN, Ph.D. Professor / Deputy Dean of Graduate School Universiti Putra Malaysia

Date: '1"4 SEP ZODJ

xi

Th is thesIs submitted to the Senate of Unlversltl Putra M alaysia has been accepted as fu lfi lment of the requ i rement for the degree of Doctor of Ph ilosophy

XII

AINI IDERIS, Ph.D. Professor / Dean of G raduate School Unlversltl Putra Malaysia

Date 08 NOV 2001

DEC LARA TION

I hereby declare that the thesis is based on my original work except for quotations and citations, which have been duly acknowledged. I also declare that it has not been previously or concurrently submitted for any other degree at UPM or other institutions.

c

---- --�

MOHAMMAD TOKHMAFSHAN

Date: \ L\ / q I 0 \

xiii

TABLE OF CONTENTS

D E D I CATI O N ABSTRACT ABSTRAK AC KNOWLEDG E M E NTS APP ROVAL SH EETS DECLARATION FORM L IST OF TABLES L IST OF F I G U R ES L IST O F P LATES L IST OF ABBREVIAT ION/NOTATION S

CHAPTER

"

G E N E RAL I NTRODUCTION

L ITERATU R E REVI EW Charactenstlcs of the Known Penaeld S h nmp Viruses

Bacu lovl rus M id-g ut G land NecrOSIs Virus Baculovlrus Penael Hepatopancreatlc Parvo- l i ke v i rus I nfect ion Hypodermal and H ematopoietic NecroSIS Virus Shnmp I ndov l rus Lympho lda l Parvo-l ike Virus Lympholda l Organ Vacuol ization Virus Penaeus monodon baculovlrus Penaeld Hemocytlc Rod-shaped Virus Reo-l ike Virus Rabdovl rus of Penaeld S h nmp Ta u ra Synd rome Virus White Spot Synd rome virus Yel low Head Virus

D iagnostic Techniq ues for Vira l I nfect ion Wet mount m icroscopy H isto logy and H istochemical Test Tra nsmission E lectron M ICroscopy Molecular Methods In situ Hybnd lzatlon Po lymeraes Cha in React ion

Relat ionsh ip of EnV i ronmenta l Factors With D isease O utreak

Sa l i n ity

X IV

Page I i i i i VI

IX XI

XI I I xvI X IX XX I XX i i i

1

1 1 1 2 1 2 13 1 4 1 6 1 8 1 9 20 2 1 2 5 25 27 27 28 3 1 35 35 35 36 36 37 38

40 4 1

Temperature 43 pH 45 Dissolved Oxygen 48

Bio log ica l and p hysio log ical C ha ractenstlcs of Penaeus semlsu/catus 49

State of Shnmp aq uacultu re I nd ustry I n I s lamic Republ ic of I ra n a n d other Countnes 51

III DETECTION AND I DE NTI F I CATI O N OF V I RAL D ISEASES OF C U LTURED PENAEUS SEM/SULCA TUS I N I R I RAN I ntroduction 55

Matena l and Methods 57 1 Detection and Identificat ion of Viral D iseases of C u ltu red Penaeus Semlsu/catus In I R I ran 57

Col lection of Specimens 57 2 V i ra l Disease DiagnosIs 58

Wet Mount M icroscopy and Gross Examinat ion of Live Shnmp 58 H istopatho log ical and H istochemical Techn iq ues In S hnmp D isease DiagnosIs 62 TransmiSS ion Electron M Icroscopy 63

3 The Preva lence of Viral I nfect ion ( R O I ) and the Grad ing of their Seventy of I nfection (SO l ) 65

Estimation of Preva lence 65 Terminology 66

Resu lts 72 Hepatopancreatlc Parvo-l i ke Virus (HPV) Gross Sign and H i stopathology 72 H istochemical Stud ies 74 U ltrastructra l Cytopathology and V i rus Morphology 75 Penaeus Monodon Bacu lov l rus (MBV) Gross Sig n and H istopathology 76 H istochemica l Stud ies 79 U ltrastructra l Cytopathology and Virus Morphology 79 Prevalence and Seventy of MBV and

HPV In Penaeus Semlsu/catus 81 DISCUSSion 87

IV SUSCEPTI B I L ITY OF THE D I FFERENT LARVAL AND POSTLARVAL STAGES O F PENAEUS SEMISULCA TUS TO M BV I ntroduction Matenals and Methods Resu lts D ISCUSSion

xv

1 1 4 1 17 1 22 1 35

V THE E FFECT OF pH AND SAL I N I TY ON THE OCCURRENCE OF M BV IN PENAEUS SEMISULCA TUS I ntrod uction Materia ls and Methods Resu lts D Iscussion

VI E F F I CACY OF CALC I U M HYPO C H L O R I D E AND F O R MAL I N

VI I

AS D I S I N F ECTANTS FOR M BV I N PENAEUS SEMISULCA TUS I ntrod uct ion Materials and Methods Resu lts D Iscussion

G E N E RAL D ISC USS ION AND RECOMM E N DATIO N

R E F ERENCES B I OGRAP H I CAL SKETCH

XVI

1 40 1 44 1 48 1 59

1 63 1 66 1 69 1 80

1 86

1 97 2 1 6

LIST OF TABLES

Table Page 2 1 Characteristics of the known types of penaeld sh rimp virus 33

2 2 The geograph ical d istrib ut ion of v i ral d iseases 34

3 1 Health state of specimen (P semlsulcatus) collected between March 1 997 April 1 998 from farms In Three provi nces of I ra n 6 0

3 2 Health state of specimen (P semlsulcatus) collected between March 1 997 to April 1 998 from hatchery In Three provinces of Iran 6 1

3 3 Observed cytopatholog lcal stages of development of a M BV infection I n P semlsulcatus hepatopa ncreatlc and a nter ior midgut epithel ium 67

3 4 A generalised scheme for ass ign i ng a n umerical q ualitative value to seventy g rade of i nfect ion , surface i nfestat ion and d isease synd rome severity 68

3 5 A generalised scheme for assig n ing a n umencal q ualitative value to severity g rade of M BV I nfect ion 6 9

3 6 A generalised scheme for assIgn ing a n umerical q ua l itative value to seventy g rade of H PV infect ion 70

3 7 RO I a nd SOl of the V i ral i nfect ion from P semlsu/catus postlarvae In I ra n (March 1 997 to Apn l 1 998 ) 83

3 8 RO I and SOl of the V i ral i nfect ion of P semlsulcatus ad ults I n I ran (March 1 997 to April 1 998 ) 84

4 1 Severity of i nfect ion (expressed as g rade of i nfect ion) of M BV In P semlsu/catus exposed to d ifferent stages of zoea 1 26

4 2 Percentage of I nfection (RO I ) of M BV to P semlsulcatus exposed In d ifferent stages of zoea 1 26

4 3 Seventy of i nfect ion (expressed as g rade of I nfect ion) of M BV to P semlsu/catus exposed In d ifferent stages of mysls 1 27

4 4 Percentage of I nfection (RO I ) of M BV to P semlsulcaus exposed In d ifferent stages of mysls 1 27

4 5 Seventy of infect ion (expressed as g rade of infection ) of M BV to P semlsu/catus exposed at d ifferent stage of PL 1 28

XVII

4 6

47

5 1

5 2

5 3

5 4

6 1

6 2

6 3

6 4

Percentage of infection (ROI) of MBV to P semlsu/catus exposed at different stage of PL

The accumu lative morta l ity rate (%) In diffe rent l a rva l and postlarval stages of P semlsulcatus

Rate of i nfection (RO I ) of PL 1 2 P semlsulcaus Infected with MBV In d ifferent sa lin ity

Seventy of infect ion (SOl ) of PL 1 2 P semlsulcatus Infecteed with MBV In d ifferent sa l in ity

Rate of i nfection (ROI) of PL 1 2 P semlsulcaus Infected With With MBV In d ifferent pH concentration

Seventy of Infection of PL 1 2 P semlsulcatus Infected With M BV In d ifferent p H concentration

Rate of infection (RO I ) of PL 1 2 P semlsulcaus Infected MBV I n d ifferent ca lC ium hypoch londe (TC)

Seventy of infection (SOl ) of PL 1 2 P semlsulcatus Infected With MBV In d ifferent ca lC ium hypochlonde (TC)

Percentage of infection (RO I ) of PL 12 P semlsulcatus Infected With MBV In d ifferent formal in concentration

Seventy of infect ion (SOl ) of PL 1 2 P semlsu/catus Infected With MBV In d ifferent forma l in concentration

XVI I I

1 29

130

15 1

15 2

153

153

1 72

1 73

1 74

1 75

LIST OF FIGURES

F ig u re Page 1 1 Fa rmed shrimp p roduct ion I n I ra n , 1 992 - 2000 8

1 2 Map of I R I ra n showing the sou rce of samp les Fa rmed 9

1 3 Farmed shrimp p rod uction by species, 1 992 - 2000 1 0

3 1 Farm h istory record for shnmp v i ra l d iseases 59

3 2 General external adu lt anatomy of shnmp 7 1

3 3 Genera l Interna l adu lt anatomy of shnmp 7 1

3 4 P reva lence of the vira l i nfect ion ( M BV a nd H PV) of cu ltu red P semlsu/catus based on the sample col lected from M a rch 1 997 to Apn l 1 998 85

3 5 Seventy of i nfect ion g rad ing of the v i ra l i nfect ion (MBV a n d H PV) of PLs and su bad u lts P semlsu/catus based on tota l n umber of cases from March 1 997 to Apnl 1998 86

4 1 Accu mulatrve morta l ity I n the d ifferent l a rval and post larva l stage of MBV-Infected and control g roups of P semlsu/catus 1 3 1

4 2 Genera l g rowth rate exh ib ited by the M BV-Infected and control g roups of d rfferent l a rva l a nd postla rva l stages of P semlsu/catus 1 32

5 1 Proced ure used to study the effect of d ifferent p H leve l on the viability of MBV 147

5 2 Effect of sa l i n ity on M BV InfectiVity I n P L 1 2 of P semlsu/catus The shnmp were ana lysed after 6 days post exposu re

5 3

5 4

Effect of p H o n M BV rnfectrvlty In P L 12 P semlsu/catus The sh rimp were ana lysed 6 days post exposure

Accumulative mortal ity I n P L 1 2 P semlsu/catus Infected with M BV and the contro l g roups ma inta ined at d ifferent sa l in ity

XIX

1 55

1 56

157

5 5

6 1

6 2

Accumu lative morta l ity I n PL 1 2 P semlsu/catus Infected w ith M BV and the control g roups ma i nta i ned at d ifferent pH

Procedure used to study the efficacy of ch lori ne as d iS infectant for M BV

Seventy of I nfect ion (express as g rade of I nfect ion) on M BV infectiV ity I n P L 1 2 P semlsu/catus at d ifferent con centrat ion of TC The shrimp were analysed 6 d ays post-exposu re

6 3 Seventy of I nfect ion (exp ress as g rade of i nfect ion) on M BV infectiV ity In PL 1 2 P semlsu/catus at d ifferent concentrat ion of forma l i n The shrimp were ana lysed 6 d ays post­exposu re

6 4 Accumulat ive morta l ity I n PL 1 2 P semlsu/catus of MBV Infected and cont:-ol g roups at d ifferent Concentration TC

6 5 Accumulative morta l ity I n PL 1 2 P semlsu/catus of M BV Infected and control g roups at d ifferent concentrat ion forma l in

xx

1 58

1 67

1 76

1 77

1 78

1 79

LIST OF PLATES

P late Page

3 1 H PV infect ion I n Juven i le P semlsu/catus 1 0 1

3 2 The en large Inc lus ion bod ies I n Juven i le P semlsu/catus s howi ng the hypertropled n u cleu s 1 0 1

3 3 The advan ce stage of H PV I nfect ion showing hypertroph ied nucleus , large wel l development I ntranuc lear 1 02 i ncl us ion bod ies, basoph i l i c i nc lus ion bod ies

3 4 Feu lgen sta in ing of I nc lus ion body of H PV i nfection I n P semlsu/catus 1 02

3 5 A h ig her magnification of the hepatopancraetlc t issue showing g ra n u lomas 1 03

3 6 F luorescent micrograph of AO sta i n i ng of H PV-Infected hepatopa ncreatlc t issue 1 03

3 7 Methylene blue sta i ned sect ions showing hepatopancreas tubu les heavi ly I nfected with H PV 1 04

3 8 Stage 1 H PV I nfection 1 04

3 9 Stage 2 H PV I nfect ion 1 05

3 1 0 Stage 3 H PV infect ion 1 05

3 1 1 A h igher magn ification of the H PV i nclus ion body 1 06

3 1 2 H i gh mag n ification of H PV partic les 1 06

3 1 3 Wet mount view of t issue squash preparation of the hepatopancreas (HP ) from P semlsu/catus post larvae with M BV I nfect ions 1 07

3 1 4 Hepatopancrease of P semlsu/catus with M BV Infected cel ls In the developmenta l stages (stage 1 ) and (stage 2 ) 1 07

3 1 5 Hepatopancreas of P semlsu/catus I nfected with MBV 1 08

XXI

3 1 6

3 1 7

3 1 8

Hepatopancreas ce l ls of P sem/sulcatus I n advan ced (stage 3) M BV i nfect ion

Hepatopancreas of P sem/sulcatus with M BV I nfected ce l ls

Methylene b lue sta in showing typ ica l h istopatho logy of M BV i nfection I n Hepatopa ncreas

3 19 ACrid ine orange sta i ned sect ion observed by fl uorescent microscope s howing karyop lasms and OB a re In ye l low­g reen

3 20 Stage 1 M BV I nfected hepatopancreatocyte

3 2 1 Hepatopancreatocyte with stage 1 M BV i nfect ion

3 22 A h ig her mag n ification of the n ucleus of stage Infected hepatopancratocyte

3 23 The basa l port ion of a stage 2 M BV

3 24 Stage 3 M BV I nfected hepatopancreatocyte

3 25 A h igh mag n ification of a stage 3 M BV infect ion

2 M BV-

3 26 A h igh mag n ification of a n aggregat ion of nonoccluded MBV

4 1

42

4 3

4 4

Hepatopancreas of mysls 3 P sem/sulcatus showing the normal cel l (Grade 0 ) on the fi rst day

Hepatopancreas of mysis 3 P semlsu/catus stage 1 of M BV i nfect ion

Hepatopancreas of P L 6 of P sem/sulcatus showin g the stage 2 of MBV

Hepatopancreas of PL 6 of P sem/sulcatus showing the stage 3 of M BV

XX I I

1 08

1 09

1 09

1 1 0

1 1 0

1 1 1

1 1 1

1 1 2

1 1 2

1 1 3

1 1 3

1 33

1 33

1 34

1 34

LIST OF ABBREVA TIONS

AM accumu lative morta l ity

AO acndme orange

BBV Bennettae baculovlrus

BKC benza lkon ium chlonde

BMNV bacu lovl ral midgut g land necrosIs

BP Baculovlrus penael

CAl Cowdery type A Inc lUS ion body

C PV can ine parvov l rus

DO d issolved oxygen

DNV densonucleosls v i rus

dsRNA d oub le-stra nded ribon ucle iC aCid

EL ISA enzyme- l i nked Immunosorbent assay

EMU e lectron microscopy u ntte

ER endoplasmiC reticu lum

FAO Food a nd Agncu lture Organ isation

GR g rowth rate

GV g ranU la r v i rus

H&E hematoxyl i n a nd eosm

H P hepatopa ncreas

H PC hepatopa n creatocyte

H PV hepatopancreatlc parvo- I lke virus

XXIII

IB

I CTV

I H H NV

I H NV

I PNV

I R DO

Kb

KDa

LM

LO

LOW

LPV

MBV

M L

MT

NBF

N PV

08

PBV

PCR

PGFRC

P H RV

P I

P I B

i nc lus ion body

I nternat ional Committee on Taxonomy of V i ruses

I nfection hypoderma l & hematopo ietic necrosIs v i rus

I nfect ion hematopo ietic necros Is v i rus

i nfect ion pancreatic necros Is v i rus

sh rimp I r ldovlrus

k i lo base

k i lo Da lton

I Ig ht microscopy

lymphoid organ

lymphoid organ vacuol izat ion virus

lymphoid parvo-l i ke v irus

monodon bacu lovl rus

membranous labYrinth

metric tons

nuclear buffered forma l i n

n uclear polyhed rosls v irus

occlUSion body

plebJeus bacu lovlrus

polymerase chain react ion

Pers ian Gu lf Fisheries Resea rch Centre

penaeld haemocytlc rod-shaped v i rus

post I noculat ion

polyhedral i ncl us ion body

XXIV