The induced maturation and breeding of Penaeus monodon in captivity was first developed in India in seventies (Alikunhi et al 1977; Alikunhi and Hameed Ali 1977; Muthu and Laxminarayana 1977). With the later standardisation of hatchery systems with designs, feeding schedules etc., amenable for convenient operation, shrimp hatcheries started proliferating not only along the Indian coastline but also along the coastline of the countries of the sub-continent

Imelda, Joseph

Mishra, S S

Rao, L H

Sudheesh, P S

CMFRI Digital Repository

Vol. 20 No. 6FISHING CHIMES ~b ^ <Quality Assessment of Hatchery reared PosMarvae of Tiger Shrimp Penaeus monodon (Fabrieius)Im e ld a  J o sep h * , L .H .R a o , S .S .M ish ra  and  P .S .S u d h eesh  Central Institu te o f  Brackishwater Aquaculture, 101/B, M ahalingapuram , Chennai - 600 034The authors followed a simple and practical methodology for determining the post-larval (PL) quality o f  Penaeus monodon  produced in eight commercial sh r im p  h a tc h e r ie s  in and around Chennai. Studies were carried out by tak ing  into co n s id e ra t io n  various parameters like, visual observations, microscopic studies and stress tests by salinity drop to less than 50% o f  the ambient and exposure to formalin at 100 ppm and 200 ppm concentrations for 2 hours. PL from three o f  the hatcheries were found to be not o f  good quality as per the studied norms. MBV occlusions were present in 15% to 30% PL from another two hatcheries. Poor quality of  post-larvae encountered in the present study can be attributed to lack o f  hygiene, improper feeding regime, and high stocking density which is stress inducing.T h e  in d u c e d  m a tu ra t io n  and breed ing  o f  P en a eu s m onodon  in captivity was first developed in India in seventies (Alikunhi et al 1977; Alikunhi and Hameed Ali 1977; Muthu and Laxminarayana 1977). With the later standardisation o f  hatchery systems with designs, feeding schedules etc., amenable for convenient operation, shrimp hatcheries started proliferating not only along the Indian coastline but also along the coastline o f  the countries o f  the sub-continent.It is reported that shrimp larval mortality is a global phenomenon and this is attributed to increased stocking density, inappropriate and insufficient feeding and occurrence o f  major disease problems (Liao 1985).One o f  the major diseases of  P. m onodon  was identified as monodonbaculovirus (M BV ) (Lightner and Redman 1981; Lightner 1983). It was found that a major factor for mortalities in shrimp ponds that occurred mainly in Andhra Pradesh and Tamil Nadu during nineties could be due to the outbreak of MBV. In fact, a similar situation of  MBV occurrence was reported to be the cause o f  mass mortality of  shrimps inTaiwanese shrimp ponds in 1988 (Liao 1989). In this background, the need for quality control measures for PL was emphasised and there were followed by several hatchery owners as well as farmers. PL harvest in hatcheries, transportation o f  PL to farms, their acclimation to farm conditions etc. are important aspects o f  shrimp farming (Olin and Fast 1989). There is a dearth information on PL quality studies and the p resen t  one was d irec ted  at evaluating the quality o f  PL o f  P. m o n o d o n  p ro d u c e d  in the  e igh t  commercial shrimp hatcheries.M a ter ia ls  and M eth o d sA p rac t ica l  m eth o d o lo g y  was followed for quality evaluation of  P. monodon  post larvae. Various criteria followed for this include length and w e ig h t  m e a su re m e n ts ,  v isua l  observations like movement, behaviour, feeding and pigmentation. Muscle to gut ratio (MGR) was estimated by m icroscopic  observations using a calibrated oculomotor, where, the ratio of  diameter o f  the sixth abdominal muscle to width o f  gut directly above it is determined (Bauman and Scura 1990). Further, moulting conditions, muscle deform ities, hind gut appearance, appendages, setae, rostral spine count were also observed (Olin and Fast 1992).Routine microbiological observations fo r  d isea se  d iag n o s is  (B ray  and Lawrence 1989) like bacterial necrosis, filamentous forms, fungus, protozoan attack etc., were done, and MBV infections were diagnosed by their characteristic occlusion bodies in wet mounts o f  hepatopancreas using 0.05% malachite green stain. Stress tests by exposing PL to 100 ppm and 200 ppm formalin and salinity drop to 10 ppt from ambient for 2h (Tackaert et al1989); Bauman and Jamandre 1990) were also done and found to be practicable and convenient for application to assess PL quality. Hatcheries were selected on random basis and samples were collected during February to May. PL was obtained in two cycles from each o f  the hatcheries.R e su lts  and  D iscu ss io nMany workers have reported that PL length and weight are dependent on the diet supplied to them (Wilkenfield et al., 1984; Fuze et al., 1985 and Samocha et al., 1989). The present study also has shown that size o f  the PL is dependent on the diet given but not much related to quality. PL o f  2 to 8 mg and 9 to 13mm lengths were e n c o u n te re d  in the  p re se n t  observations. Table 1 shows the mean length and weight o f  PL along with standard deviation, from different hatcheries. PL is generally planktonic fo r  5 to 7 days  fo l lo w in g  its metamorphosis from mysis stage (upto PL5 to PL?). During this time they actively swim using their pleopods with occas iona l  ab rup t  m ovem ents  by vigorous tail flicks. The age o f  PL samples in the present study varied from PLS to PL20. Erratic behaviour like irregular, zig zag or spiral swimming is^ P r e s e n t  a d d r e s s  : N R C  o f  C I B A ,  N a r a k k a l ,  C o c h in -6 8 2  50 5 ,  K er a la[X44> September 2000Vol. 20 No./6FISHING CHIMESTable 1: Mean length, weight, MGR and rostral spine count along with standard o f Penaeus monodon Post larvae from different hatcheriesHatcheryCodeLength(mm) Weight(mg) Muscle: Gut Ratio (MGR)RostralSpineI 8.7+0.46 2.1+0.51 5.6+0.87:1 3/1II 10.5+0.84 2.8+0.36 3.8+0.68:1 3/2III 12.0+0.98 .. 6.7+1.13 3.9+1.90:1 6/2IV : 11.3+1.10 6.1+1.02 8.7+1.80:1 4/2V 10.9+0.94 3.6+1.57 6.0+0.91:1 6/3VI ' 9.5+0.50 2.6+0.50 6.3+0.74:1 4/2VII 9.4+1.0 2.3+0.68 4.2+0.61:1 5/2v m 10.7±1.0 3.2+0.49 7.7+1,79:1 5/2Table 2: M orphological, physiological and pathological observations o f Penaeus monodon  Postpathological observations o f  PL from differen t ha tcheries . Feeding, as evidenced by full gut, is not clearly conclusive o f  PL quality. All PL from hatcheries coded as V and VI had full guts. Others had 45 to 95% PL with ful I gut. It was noticed PLs at hatqheries II, III and VII, which had 30% and more PL with empty gut were not o f  good qual ity. This is in conformity with the results o f  Bauman and Jamandre (1990) who reported that PL stock with 30% or more o f  it with empty gut was not o f  good quality as per stress test result obtained. Muscle deformity was observed in 5 to 10%) o f  PL from hatcheries II and III.larvae from different hatcheriesParameters studied for quality assessmentHatchery Codel i f e II HI IV V VI VII VIIIFulness o f  Stomach. (%) : 90 70 60 80 100 100 45 85Muscle Deformity (%) Nil 5 10 Nil Nil Nil Nil NilIncomplete Moulting (%) 10 10 15 5 Nil Nil Nil NilSwollen Hind Gut (%) Nil Nil 10 10 Nil Nil ' Nil NilBroken Appendages (%) Nil 10 15 10, Nil Nil 20 NilBacterial Necrosia (%) Nil 5 . 15 Nil Nil Nil .. 15 NilFilamentous Forms (%) Nil Nil Nil Nil Nil Nil Nil NilF u n g u s (%) Nil Nil Nil Nil Nil Nil Nil , NilMBV Occlusion bodies (%) Nil Nil 15 Nil. Nil Nil -  15/ Nil;Protozoans (%) Nil Nil ‘ Nil Nil Nil - Nil Nil NilOthers (%) Nil 30 Nil Nilt . Nil ; Nil t  Nil NilTable3 Showing survival rate of Penaeus monodon Post larvae from different hatcheries on exposure to stress testsHatcheryCode% survival at lOppt salinity% survival at 1 OOppm formalin% survival at200ppm formalinI . 80 87 8011 • . 4 6 70 68m 87.3 10 7IV 88 93.3 90V 80 90 90VI 100 100 100VII 75 65 60VIII 100 100 100indicative o f  either physical deformities or other problems o f  PL. They should neither be lethargic nor should bounce off from the bottom o f  rearing tanks(Olin and Fast 1992). It is observed in the present studythatPls(I,IV,V,VI& VIII) from five hatcheries were satisfactory in their visual qualities. These PLs were actively swimming, some benthic, well fed with normal pigmentation and well spread tail fan. Seeds from other hatcheries (II, III and VII) were slender, less active and were poorly fed with some abnormal pigmentation (II and III). R edd ish  p ig m en ta t io n  re su l ts  from  s tre ssed  h a tc h e ry  c o n d i t io n s  (Bauman and Jamandre 1990).T ab le  2 show s the re su lts  o f  m orpho log ica l,  physio log ica l andBroken appendages were present in the range o f  10 to 15%PL fro m  th ree  hatcheries (II, III and IV). As per r e p o r t s ,  fo r  a h e a l th y  PL, the h e p a t o p a n c r e a s  and a n te r io r  gut should be full and w e l l  d e v e lo p e d ,  w i th o u t  any swelling in thehind gu t .  T heappendages should be in tact without any deformities (Olein and Fast 1992). The criteria were satisfactory in the case o f  PL from two hatcheries only (V and VIII).The data on pathological observation (Table 2) shows 5 to 15% of PL from three hatcheries (II, III and VIII) were infected with bacterial necrosis. All PL from all the e ight ha tche r ie s  were free from filamentous forms, fungi and protozoans. Hatchery II had 30% o f  its seed infested with Zoothamnium  sp. MBV occlusion bodies were encountered in 15% of PL from two hatcheries (I II and V11). The intra nuclear  occ lus ion  bodies  in hepatopancreas have been reported from PL2 stage onwards (Chen 1989a). In Thailand, PL are detected with MBV occlusions as early as PL5 and PL|0 (Nash1990). C J P[X45> September 2000 <4|XjVol. 20 No. 6FISHING CHIMESF o r  q u a l i ty  a s s e s s m e n t  byp a th o lo g ic a l  o b s e r v a t io n s ,  it is important to note that a healthy PL does not accommodate any type of  pathogenic bacteria, fungi or protozoa in its body. The setae and gill chambers will be clean o f  debris and bacteria (Olin and Fast 1992). In the present study also, healthy PL from three hatcheries were free o f  all types o f  bacteria and other forms.The stress tests were intended to evaluate PL hardiness by subjecting them to sudden change in salinity and exposure to high concentrations of  formalin. Formalin is used for the above test because, it is being widely used as a disinfectant or for fast moulting o f  PL in hatcheries. Also formalin is easily available in all the hatcheries to perform such tests. It was kept in view that higher concentration (100 and 200ppm) o f  formalin will inflict some extent o f  stress on the PL causing a sort o f  irritation. Exposure to low salinity to cause stress on PL is very much in practice. This bioassay would allow the identification o f  healthy post larvae, which is not evident otherwise (Gomez et a l 1991). P. m onodon  could tolerate an abrupt reduction in salinity from 30ppt with less than 20% mortality, if the range o f  reduction was within 20ppt. In the present study, it is observed that, out o f  the PL from one of the hatcheries (hatchery II) only 46% survived at 1 Oppt salinity. PL from all the other hatcheries showed 80 to 100% survival after 2 h exposure in lOppt salinity (Table 3). Charmantier et a l(  1988) found that PL should be more tolerant to salinity variations upto PL20 stage. They also found out that age influences the acclimation capacity o f  penaeid post larvae. .Ontogeny of osmoregulatory capabilities with larvae and post larvae o f  P.japonicus is reported by the above w orkers .  C om paring  the resu lts  obtained by the authors with those published for different species, the authors found that age o f  the PL and feeding regime followed during the larval rearing period assured good quality PL. Also, as stated by Gomez et al (1991), it can be concluded that strong salinity resistance may be a se c u r i ty  f a c to r  fo r  g ro w -o u t  performance of  PL. AstudybyTackaert et al (1989) showed that resistance of  PL to salinity stress could be enhanced with n-3 HUFA enrichment o f  Artemia when it is supplied as food source.Data o f  survival percentage o f  PL in the two formalin concentrations (100 and 200 ppm) are shown in Table 3. Effects o f  two formalin concentrations on the fry do not differ significantly. PL from three hatcheries (II,III and IV) showed less than 70% survival. The rest were considered hardy and healthy PL. On exposure to 100 and 200 ppm formalin (35% aqueous solution) for 2 h, less than 30% mortality is expected for quality ones (Olin and Fast 1992).The evaluation results showed that Muscle-Gut Ratio (MGR), diagnosis o f  MBV occlusion bodies and stress tests are suitable criteria, which are useful to differentiate healthy PL from others. It is recommended to discard PL with MBV occlusion bodies and MGR less than 4:1. Visual and other microscopic observations were not found to be truly conclusive o f  quality studies, though 'they were useful. Also it was found necessary to have details about larval rearing period for knowing the feeding reg im es, w ater  quality  s tandards, stocking density and hygiene practices followed in various hatcheries. Age a lso  d e te rm in e s  the  g ro w -o u t  performance o f  PL and it is concluded that PL of P. m onodon  will be the best for stocking at PL,g to PL20 (10 -12mm length) stages. All the tests followed for quality assessment o f  PL were found to be ideal for laboratory as well as field conditions and they do not require high s c ie n t i f i c  sk i l l  o r  s o p h is t ic a te d  equipments.Further rearing o f  PL from all hatcheries in post larval tanks for 10 to20 days from the date o f  procurement was also carried out during this study. They were fed with chopped clam meat and particulate feed. Post-larvae from five hatcheries (I,IV, V, VI and VIII) had shown higher survival rate (above 80%).Recommendations o f  the study along with remarks are given in Table 4. PL from hatcheries V, VI and VIII were o f  very good quality and those from II and IV were o f  quality above average. Post larvae from hatcheries II, III and VII were found unsuitable for stocking)C4jT> September 2000Vol. 20 No. 6^TFISHIM G CHIMESin grow-out ponds. Also it should be borne in mind that good quality PL will get easily acclimatized to the stress during transport, harvest and to varying conditions in grow-out systems. It is possible to produce good quality PL only by following strict and optimal larval rearing practices.Further, PCR techniques followed in quality assessment o f  broodstock and of post-larvae collected from wild as well as from hatcheries, would need more o f  sophistication.A c k n o w le d g e m e n tThe authors are thank fu l 'to  the D ire c to r ,  C e n tra l  I n s t i tu te  o fBrackishwater Aquaculture (CIBA), Chennai for the facilities provided. Their thanks are also due to the various shrimp hatchery owners who supplied us the post larvae o f  P. monodon.R e f e r e n c e sALIKUNHI, K.H., A. POERNOMO, S.ADISUKRENSO, M.BUDINO AND S .B U SM A N , 1975. P re l im in a ry  o b s e rv a t io n s  on in d u c t io n  o fm a tu ra t io n  and  s p a w n in g  inP .m o n o d o n  F a b r ic iu s  and  P.m erg u ien sis  de M an by eyesta lk  extirpation. Bull Shr Cult Res Cent, 1:1- 11.ALIKUNHI, K.H. and HAMEED ALI, 1978. Induction o f  maturation and spawning on pond grown stocks o f  penaeid shrimps for large-scale seed production (Abstract). Proceedings of first National Symposium on Shrimp Farming, 16-18, Bombay.B au m an , R .H . and  D .R. JAMANDRE, 1990. A practical method for determining quality o f  Penaeus monodon (Fabricius) fry for stocking in grow out ponds. In Technical and economic aspects o f  shrimp farming. P roceedings o f  the A quatech  ’90 conference, ed. M.B New, H. de Saram and T. Singh, Infofish, Kuala Lampur, Malaysia, ppl24-131.BAUMAN, R.H. and E.D. SCURA, 1990. Determining the quality of  P en a eu s  m o n o d o n  p o s t  la rvae  (Abstract) World Aquaculture Society21 st annual conference, 101 p.CH A RM  A N TI E R , G ., M.C H A R M A N T IE R  C A U R E S , N. BOURAVICHA, P.THUET, D.E. AIKEN and J.P. THRILLES, 1988. Ontogeny of osmoregulation and salinity tolerance in two decapod crustaceans: Homarus americanus and Panaeus japonicus  BollBull., 175:102-110.COUCH, J. A., 1974. An enzootic nuclear polyhidrosis virus o f  pink shrimp: ultrastructure, prevalence and enhancement. J  Invert Pathol. ,24:311- 331.COUCH, J. A., 1981. Viral diseases o f  invertebrates other than insects. In: ed. E.W. Davidson, Pathogenesis of  invertebrate  diseases. Allanheld, OsmunPubl.,Totowa,N.J.ppl27-160.FUZE, D.M., J.S. WILKENFIELD and A.L. LAWRENCE, 1985. Studies on theuseofbo iledch ickeneggyo lkas  feed for rearing penaeid shrimp larvae, Texas JSci. XXXVII: 371-388.GOMEZ, R. D., J.M. RODRIGUEZ andJ.MORALES, 1991. Stress tests: a practical tool to control post larval shrimp quality. In: ed. P.Lavens, P. Sorgeloos, E. Jaspers and F. Ollevier, L a r v i ’9 1 -F ish  and C ru s ta c e a n  Larviculture Symposium, European  A q u a c u ltu re  S o c ie ty , S p e c ia l  Publication, No. 15, Gent, Gelgium.HIRONO, Y. and M. LESLIE, 1992. Shrimp culture industry in Ecuador. In: eds. A.W. Fast and J. Lester, Marine Shrim p  cu l tu re  : P r in c ip le s  and practices. Elsevier Science Publishers - pp783-835..LIAO, I.C., 1985. A brief review o f  the larval rearing techniques of  penaeid prawns. In: eds. Y.Taki, J.H. Primavera and J.A. Liobrena, Propeedings o f  the first international conference on the culture o f  penaeid shrimps, Iloilo City, Philippines, pp65-78.LIAO, I.C., 1989. Penaeus monodon culture in Taiwan: Through two decades o f  growth. In tJF ishTechnol., 1:16-24.LIGHTNER, D.V., 1983. Diseases of cultured penaeid shrimp. In: ed. J.P.McVey, CRC Handbook o f  Mariculture, Voll, Crustacean aquaculture, CRC Press. Inc., Boca Raton, Florida, pp289- 320.LIGHTNER, D.V., 1988. Diseases of cultured penaeid shrimps and prawns. In eds. C.J. C inderm an and D.V. Lightner, Disease diagnosis and control inNorth American marine aquaculture, Elsevier, Amsterdam, pp8-133.LIGHTNER, D.V. and REDMAN R.M., 1981. A baculovirus caused disease ofthe penaeid shrimp, Penaeus monodon, J  Invert Pathol., 3 8:299-3 02.LIGHTNER, D.V., R.M. REDMAN andT .A . BELL, 1983c. Observations on the  g e o g ra p h ic  d i s t r ib u t io n ,  pathogenesis and morphology o f  the baculovirus from Penaeus monodon  Fabricius. A quaculture,32:209-233.M U T H U , M .S . andA. L AX M IN A R A  Y A N A , 1977.Induced maturation and spawning of Indian penaeid prawns. Indian J  Fish., 24:172-180.N A SH , G .L .,  1990. P en a eu s  m onodon  grow out diseases. In: eds., M.B.New, H de Saram and T.S.Singh, Technical and economic aspects o f  shrimp farming. Proceedings o f  the Aquatech ’90 Conference, Infofish, Kuala Lumpur, Malaysia, pp 124-131.OLIN, P.G. and A.W. FAST, 1992. P e n a e id  P L  h a rv e s t ,  t r a n s p o r t ,  acclimation and stocking, In: eds, A.W. Fast and L.J. Lester, Marine shrimp culture: P r inc ip les  and prac tices ,  E lsevier Science Publishers , B.V. pp301-329.T A C K A E R T ,  W .P .A B E L I N ,  P.DHERT and P.SORGELOOS, 1989. S t re s s  r e s i s t a n c e  in p o s t  lkrval penaeid shrimp reared under different feed ing  p ro c e d u re s  (A b s t ra c t ) ,  J  W o rld A q u a cu lt S o c ., 20:74p.W I L K E N F I E L D ,  J .S . ,  A .L .  LAWRENCE and F.D.KUBAN, 1984. Survival, m etam orphosis  and growth o f  penaeid  shrimp larvae reared in a variety o f  algal and animal foods, J  W orld A q u a cu lt S o c ., 15:31-49.[X4?> S e p te m b e r 2 0 0 0  < 4 jX li

Quality Assessment of Hatchery reared Post Larvae of Tiger Shrimp Penaeus monodon (Fabricius)

http://eprints.cmfri.org.in/9229/1/10.pdf

Quality Assessment of Hatchery reared Post Larvae of Tiger Shrimp Penaeus monodon (Fabricius)

Abstract

Similar works

Full text

Available Versions

CMFRI Digital Repository