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The purpose of this paper was to purify and amplify the DNA fragment of Penaeus monodon -type baculovirus (MBV). Using 30-50% caesium chloride gradients, MBV virions and occlusion bodies with density parameters of 1.28-1.29 and 1.32-1.33 g/ml, respectively, were purified. Two oligonucleotide primers have been successfully designed and utilized for the amplification of a DNA fragment of MBV. After 35 amplification cycles of the MBV DNA fragment, a large amount of amplified product with an approximate molecular weight of 600 bp was obtained. This is the first successfully published work on the amplification of MBV using the polymerase chain reaction (PCR). Using the same primers, DNA extracted from MBV noninfected P. monodon, P. japonicus, and P. orientalis had a negative PCR response. However, a positive PCR response was obtained from DNA extracted from MBV-infected postlarval P. monodon. DIG-dot blot hybridization technique using PCR product obtained from the present study as a probe further confirmed that the product is originated from a portion of MBV polyhedrin gene. It is also suggested that PCR product may be beneficial for an accurate and early diagnosis of MBV infection in larval shrimp.

The present study defines a culture system for heart tissue of hard clam,Meretrix lusoria (Roding). The tissue explants were cultured in six synthetic media supplemented with 10% fetal bovine serum and grown at 28° C. All of the media used in the present study support good cell migration and L15 medium gave the best result. Monolayer cell sheets of heart tissue established in 2X L15 growth medium consist of cardiac myocytes, epithelial-like, and fibroblastlike cells. Mitoses were observed in the culture system. To trigger the proliferation of cells, pronase, collagenase, insulin, fibroblast growth factor (FGF), and epidermal growth factor (EGF) were used individually or combined in the L15 growth medium. The results showed pronase and collagenase at a concentration level of 100 μg/ml promoted cell proliferation. In contrast, insulin, FGF, and EGF gave no positive result. To date, cell cultures derived from the hard clam have been subcultured 6 times. Morphologic characterizations for the cells were also performed.

Quantitative descriptions of prawn growth are important for fisheries and aquaculture management. The Black tiger prawn, Penaeus monodon Fabricius, 1798, has been cultured and studied for a long time (Anonymous, 1932). However, adequate quantitative descriptions of its complete growth are still not available. Such descriptions are particularly important for the culture of

Schizophyllum commune is a widely distributed mushroom used as an herbal medicine and an ingredient in healthy food. In this study, a protease from a fermented culture broth of S. commune demonstrated strong fibrinolytic and fibrinogenolytic activities. This fibrinolytic protease showed a suppression effect in blood coagulation in co-incubation with rat citrated blood through thromboelastographic analysis. The protease suppressed aggregation of fibrin (ogen), but not the platelets, in clotting formation and significantly decreased the clot strength. We also found very little potency in this protease to activate plasminogen, thus it exhibits the potential for an ideal fibrinolytic candidate for therapeutic applications in the future.

The nematode fauna of 369 spotted mackerel of the species Scomber australasicus, collected off the northeastern Taiwanese coast of the northwestern Pacific, was investigated monthly from April 2004 to March 2005. The following nematode species were recorded: Anisakis simplex complex, Hysterothylacium aduncum, Porrocaecum decipiens and Raphidascaris trichiuri. The seasonal variation in the infection with A. simplex third stage larva (L3) was studied throughout the 12 months. The prevalence of A. simplex L3 recorded for total fish samples was 93.6%, varying between 86.7 and 100%. There was an increase in the abundance of this nematode in spring, with the peak occurring in April. To reveal whether intrinsic factors of the spotted mackerel host contributed to infection with this nematode, fish were grouped according to their body weight, age and gonad development (reported as gonadoosomatic index, GSI), respectively, and infection parameters (i.e., prevalence, abundance and intensity) were analyzed. Results showed that abundance was significantly higher in both larger (>450 g) and older (>3 years old) fish. The gonad development of the host fish was not correlated with the intensity of the larval infection in both female and male fish. Two distinct Anisakis species were identified by PCR-RFLP, namely A. pegreffii and a recombinant genotype of A. pegreffii and A. simplex sensu stricto. These species occurred with frequencies of 97% and 3%, respectively. The usefulness of using parasites as biomarkers for spotted mackerel stock identification around Taiwanese waters was confirmed herein. A second group of 58 spotted mackerel were obtained from the coastal waters off southwestern Taiwan. In addition to the two species, A. pegreffii and the recombinant one, which were found with frequencies of 63% and 9%, respectively, an additional Anisakis species A. typica was identified with a frequency of 28% from these fish. Two spotted mackerel stocks could thus be identified based on their infrastructure of Anisakis species community and their frequency. To the best of our knowledge, this is the first report of stock identification of spotted mackerel using endoparasite biomarkers.

The present paper describes a herpes-like virus, tentatively designated as EHVF (Eel Herpesvirus in Formosa), isolated from diseased Japanese eels (Anguilla japonica Temminck & Schlegel) in Taiwan.This virus had DNA as its nucleic acid, sensitive to ether and chloroform, and resistant to freezing and thawing treatments. Enveloped mature viral particle measured 200 nm in diameter with nucleocapsid of 120 nm.The virus successfully replicated in CCF, CCT, TO-2, BGK, DK-1 and EO-2 cell lines at temperatures from 15°C to 33°C (optimal temperature 24°C). When these cells were infected with EHVF, syncytium formations were observed in CCF, CCT, TO-2, BGK, EK-1 and EO-2 cell lines. However, HeLa, Vero, L, AF, AK, BF-2, CCG, CCO, CF, CHH-1, CHSE-214, EPC, FHM, FS, JF, LF, MH and RTG-2 cell lines were refractory to the multiplication of this virus.No mortalities were observed among eels injected with EHVF, but the virus was reisolated from the kidneys and livers of infected eels 60 days after injection. On the other hand, carp injected with EHVF showed 37% mortality during 60 days and the virus was reisolated from all the dead fish and 84% of the survivors.

In the present study, occlusion bodies (OBs) of Penaeus monodon-type baculovirus (MBV) were collected from infected juvenile P. monodon and then the OBs were purified by centrifugation for 30 min at a speed of 100, 000×g using 35-65% (w/w) sucrose gradient. Analysis of polypeptides of MBV occlusion bodies showed 12 polypeptides in SDS-PAGE gel. It was also concluded that the major band with molecular mass of 62k dalton may be derived from protein of polyhedrin.

White tail disease (WTD) is a serious problem in Macrobrachium rosenbergii hatcheries and nursery ponds in Asia. The causative agents have been identified as M. rosenbergii nodavirus (MrNV) and its associated extra small virus. This is the first report demonstrating MrNV virus in M. rosenbergii displaying WTD signs in Taiwan by reverse transcriptase-polymerase chain reaction (RT-PCR). Amplified fragments of 850 and 425 bp for RNA-1 and RNA-2 of MrNV, respectively, were obtained by RT-PCR. RT-PCR products of about 850 and 1121 bp for RNA-1 and RNA-2 of MrNV were also obtained using different primer pairs. The amplicons were individually cloned into pGEM-T vector and sequenced. Using this recombinant plasmid of MrNV RNA-2 as DNA template, the non-radioactive DNA probes were prepared by PCR amplification with DIG-11-dUTP. The probes were used to successfully detect MrNV infection in the striated muscle tissues of WTD-diseased prawns using in situ hybridization. The 1121 bp genomic fragment of RNA-2 of MrNV consisted of a unique open reading frame with 1116 nucleotides, and it encoded a structural protein with 371 amino acids. The nucleotide sequence of the partial genome of MrNV RNA-2 revealed a 97% identity with an Indian isolate. A phylogenetic tree constructed using the nucleotide sequence of the viral capsid gene from insect and fish nodaviruses revealed that the MrNV Taiwan isolate could be interpreted as a new genus within the family Nodaviridae. However, its position showed more affinity with Alphanodavirus than with Betanodavirus. The study confirmed the presence of MrNV infection in freshwater prawns cultured in Taiwan suffering from WTD.

Post-larvae of Macrobrachium rosenbergii infected with white tail disease (WTD) have been reported in Taiwan. The causative agents have been identified as M. rosenbergii nodavirus (MrNV) associated with extra small virus (XSV). The present study is the first report confirming the presence of XSV virus in M. rosenbergii displaying WTD symptoms in Taiwan by reverse transcription polymerase chain reaction (RT-PCR). A 772 bp amplified product was obtained by RT-PCR, cloned and sequenced. The nucleotide sequence analysis of the 772 bp DNA fragment revealed 98% and 97% identity with XSV isolated from China and India, respectively. Comparison of the deduced amino acid sequences of the XSV partial genome showed strong homology (99% and 97%) with isolates from China and India. Phylogenetic analysis revealed the XSV-Taiwan isolate was more closely related to the Chinese rather than the Indian isolates. The results demonstrated the presence of XSV virus co-infection in M. rosenbergii cultured in Taiwan suffering from WTD.

A comparative study between EHVF (eel herpesvirus in Formosa) and HVA (Herpesvirus anguillae) was performed. Similar syncytia were produced by each virus in cell lines infected with the viruses and similar viral yields were obtained. Significant cross-reactivity was observed in neutralization tests between HVA and EHVF but HVA and EFVF were distinctly different from channel catfish virus (CCV). An electrophoretic analysis of the structural proteins of EHVF and HVA produced similar electrophoretic patterns. Western blotting analysis of the viral proteins, using antiserum against EHVF, supported the results obtained in the cross-neutralization test. In conclusion, the isolates of HVA and EHVF are tightly clustered.

Since 1993, an epizootic viral disease has occurred in net-cage cultured red sea bream, Pagrus major (Temminck & Schlegel), in Peng-hu Island located on the south-western coast of Taiwan. The diseased fish exhibited abnormal swimming and were lethargic, but few visible external signs were observed. The cumulative mortality because of the disease sometimes reached 50-90% over 2 months. Histopathogical studies of the affected fish showed enlarged basophilic cells in the gill, kidney, heart, liver and spleen. These necrotic cells were Feulgen-positive and stained blue using Giemsa. Transmission electron microscopy revealed icosahedral virions in the cytoplasm of the necrotic cells. The viral particles consisted of a central nucleocapsid (75-80 nm) and envelope, and were 120-150 nm in diameter. These results suggest that the virus belongs to the Iridoviridae. Using polymerase chain reaction (PCR), approximately 570 bp fragments were produced from the viral DNA using as a template 1-F and 1-R primers derived from red seabream iridovirus (RSIV) from red sea bream in Japan. Similar results were also obtained using nested-PCR with different primer sets (1-F, 2-R and 2-F, 1-R). Although the size and some features of epizootics of this virus differed from RSIV in Japan, it shows close genetic affinities with the latter and it is suggested that RSIV has been introduced to Taiwan.

Experiments performed to show that one of the respiratory oxygen species, hydrogen peroxide was an attractant factor for macrophage that consequently affects the phagocytosis of macrophage and gene expression. Results obtained from the present study also show that LPS-induced inflammation would cause hepatocytes to produce hydrogen peroxide which subsequently attract macrophage migration to the inflamed region and promote scavenging function. Furthermore, this reaction is suggestive of macrophage interacts with oxidative stress which promotes the transcription factors activity to cause inflammation responses and suggested hydrogen peroxide act as cellular messenger to affect permeability of calcium ion channel to increase intracellular Ca2+ concentration as a migration messenger

In the present study, the ultrastructural changes of BPK cells, a fibroblast-like cell line, derived from the kidney of juvenile black porgy Acanthopagrus schlegeli, under heat shock treatment are described.The BPK cells were maintained in L-15 medium supplemented with 10% fetal calf serum and 0.15 M NaCl at 28|C2. The heating was carried out in precalibrated water baths. Monolayers of cells, grown on coverslips in parafilm-sealed petri dishes were submerged under water for 30 min at 40|C treatments. Cells were fixed in 2.5% glutaraldehyde in 0.1 M cacodylate buffer supplemented with 6.6% sucrose, postfixed in 1% OsO4 and flat embedded in Spurr’s resin. Silver section were cut parallel to the substratum, stained with uranyl acetate and Reynold’s lead citrate, and examined in a Hitachi H-600 electron microscope at 75 KV.

Efforts were made to serotype the Vibrio anguillarum strains isolated from fish in Taiwan from 1976 to 1986. Included were 100 strains from milkfish (Chanos chanos), 10 from ayu (Plecoglossus altivelis), 1 from tiger shrimp (Penaeus monodon) and 8 from culture environments. Seven distinct serotypes (T-O-I through T-O-VII) were established from these 119 strains of V. anguillarum examined on the basis of agglutination test with thermostable (O) antigens. Eighty-five strains isolated from milkfish and 5 strains from ayu belonged to serotype T-O-I which appeared to be dominant. However, serotypes II, III, IV, V, VI and VII only occurred sporadically. Besides these, 9 strains isolated from milkfish and 1 from pond water were found to be nontypable. V. anguillarum strains PT213, LS174 and ITAL72 belong to our serotype T-O-I, ATCC19264 (NCMB6), PT24. and SG7701 to our serotype T-O-V and strain PT493 to our serotype T-O-VI.

This study describes attempts to establish a culture system for cells derived from tissues of the grass prawn Penaeus monodon. No cell growth was observed in cultures on fragment of gill, nerve, muscle, gut and hepatopancreas. However, an observable cell growth was obtained in the culture of gonad and heart cells. The best growth of gonad cells occurred in a culture system containing double strength (2X) Leibovitz's L-15 medium supplemented with 10% fetal calf serum (FCS), 30% muscle extract, 0.006g/ml NaCl and 10% lobster or grass prawn haemolymph. When the gonad cells were cultured in this medium for 7-10 days and incubated at 28-31°C, a confluent monolayer cell sheet was formed. The primary cell culture, predominantly of epithelioid cells, could be maintained for approximately two months at 28-31°c with a weekly change of medium. After the third consecutive subculture, the cells degenerated and dislodged from the flask surface.

Studies on the epizootiology of MBV infection in P. monodon showed that the incidence of MBV in postlarval and juvenile P. monodon cultured in Taiwan increased from 15-17% in 1984-1986 to 80-85% in 1988. The infection rate of MBV in P. monodon broodstock populations investigated in 1988 was approximately 50%. A survey on cultured P. penicillatus in 1987 revealed 20-25% MBV infection rate.Studies of hatchery-reared postlarval P. monodon showed that MBV infection initiated mortality. Results from these pathogenic studies showed that environmental stressors significantly affect the survival of MBV-infected postlarvae, juvenile (s) and adult P. monodon and P. penicillatus. Histopathological observations performed in the present study revealed that mortality of P. monodon broodstocks may be caused by secondary infection of pathogenic bacteria.

The cytopathology and virogenesis of monodon-type baculovirus (MBV) in the hepatopancreatic cells of the cultured shrimps, giant tiger prawn (Penaeus monodon) and red tail prawn (P.penicillatus), were investigated. In the hepatopancreatocytes of infected giant tiger prawns, F, B, R and M cells were found to be susceptible to MBV. Detailed virogenesis of MBV including formation of nucleic acid, capsid substance, envelopment and formation of occlusion bodies in hepatopancreatocytes of the giant tiger prawn was also noted. The main cytopathogenic changes accompanying MBV infection observed on membranes of the hepatopancreatocytes, and nuclear hypertrophy were due to virogenesis and polyhedrin formation.Virus particles and occlusion bodies released from lysed cells entered the intestinal tract via the hepatopancreatic lumen.In addition to the giant tiger prawn, the red tail prawn, P.penicillatus, were also found to be infected by MBV. This is a new reported host for MBV. Average size of the viron and diameter of the nucleocapsid observed in red tail prawn was signilcantly smaller than those present in giant tiger prawn. However, no significant differences were obtained when the length of nucleocapsids and size of the polyhedrin subunits were compared.

A survey of disease problems adversely affecting cultured shrimp at farms in Southern Taiwan was conducted in March of 1986. Farms selected for inclusion in the survey were experiencing a variety disease problems in their shrimp stocks, including mortality, poor growth, and reduced food conversion efficiency. Some apparently healthy cultured penaeid stocks were also sampled and examined for signs of subclinical disease. Most of the eight facilities surveyed cultured Penaeus monodon exclusively, although two also contained other species (P. penicillatus, P. vannamei, and P. semisulcatus). These were also sampled and examined. Important virus pathogens found during the survey included the P. monodon-type baculovirus (MBV) found in both P. monodon and P. semisulcatus, and infectious hypodermal and hematopoietic necrosis (IHHN) virus disease in P. vannamei. MBV was the most prevalent major pathogen encountered in the survey, and it was found in samples of P. monodon from seven of the eight locations surveyed and in the single sample of P. semisulcatus. These findings indicate that MBV is a common infectious agent in cultured stocks of these species in Taiwan.The disease hemocytic enteritis (HE) was also commonly observed in shrimp from five of the eight locations surveyed. This may indicate that the disease, which may be caused by an enteric toxin produced by certain types of blue-green algae, is an important disease of cultured shrimp in Taiwan. Also found in the study were two idiopathic syndromes which often, but not always, occurred together in the same shrimp. The first of these syndromes was a generalized diffuse inflammatory disease (II), which was found in several populations of P. monodon and in two stocks of P. penicillatus. The other idiopathic condition, often was observed in shrimp with II, was characterized by hypertrophy of Oka's lymphoid organ, and disassociation and metastasis of spherical clumps of cells derived from the hypertrophied organ. A number of apparently ubiquitous penaeid epicommensals were observed on the gills, appendages, and general body surface of many shrimp sampled in the survey, and some were associated with disease and mortality.

Four birnaviruses isolated from fishes in Taiwan were compared to the three known serogroups of infectious pancreatic necrosis virus (IPNV) by neutralization tests and analyses of the virion polypeptides and RNA. Two viruses isolated from different populations of Japanese eels (Anguilla japonica) in the Lukang (LKE) and Dan Sway (DSE) regions and another virus from tilapia (Tilapia mossambica) in the Lukang area (LKT) were closely related to the AB strain of IPNV. A fourth virus isolated from rainbow trout (Salmo gairdneri) in the Kukuan region (KRBT) was similar to VR-299 IPNV. This indicates that North American and European serotypes of IPNV have been introduced to Taiwan. These studies represent the first complete characterizations of birnaviruses isolated from fish in Taiwan.

An epitheloid morphology cell line designated TO-2 was established from ovary of healthy adult tilapia hybrid(Tilapia mossambica×T.nilotica).Using Leibovitz's L-15 medium with 10% fetal calf serum at 31°C, TO-2 cell line has been passed for 106 times since its initiation in October, 1981.The cells were demonstrated to be free of bacterial, fungal and mycoplasma contaminations.Optimal temperature for TO-2 cell growth was 31°C. The cells are also able to grow at 15 or 24°C. However, in 37°C the cells grew very slowly and eventually died. The growth rate of the cells varied with different serum concentrations in culture media. At a low seeding density (1.6×102-1.6×103/25cm2 flask), the plating efficiency was approximately 12%. Chromosome number at passage level of 80 ranged from 24 to 76 with a modal number of 40.TO-2 cell line is susceptible to EVE, EVA, EVEX and IPNV.

1. 1. Eyestalk unablated and unilaterally ablated Penaeus monodon juveniles had survival rates after 5 months of 75–72.5 and 67.5–60%, respectively. 2. 2. Unilaterally ablated shrimps had significantly higher (P < 0.05) growth rate than unablated shrimps. 3. 3. Eyestalk-ablatement resulted in a decrease in the haemolymph sodium concentration and an increase in the potassium and calcium concentration of shrimps. 4. 4. The osmolarity of haemolymph and total protein concentration of unablated shrimps were demonstrated to be higher than those of unilaterally ablated shrimps. 5. 5. The eyestalk-ablated shrimps possess higher total ATPase and Na+,K+-ATPase activities in the gill than those of unablated shrimps.

The enzyme-linked immunosorbent assay (ELISA) was employed for the sero-diagnosis of Angiostrongylus cantonensis infections in rats and man. Metabolic and ‘purified’ antigens of adult or juvenile A. cantonensis were evaluated by ELISA and compared against Toxocara cant's antigen for sensitivity and specificity. Sera and cerebrospinal fluid (CSF) from both rats and man gave higher ELISA values against antigens of A. cantonensis than those obtained from negative control samples. The results showed that cross reaction occurred between T. canis and A. cantonensis . Of four A. cantonensis antigens tested, a Sephacryl S-300 “purified” fraction was shown to be superior in the ELISA to determine angiostrongyliasis.

In the analysis of excretory-secretory (ES) antigens from infective third-stage larvae (L3) of Angiostrongylus cantonensis, one major component of mol.wt 91,000 was not precipitated by pooled sera of patients with eosinophilic meningoencephalitis. Monoclonal antibodies (Mc Ab) secreted from two hybridoma cell lines, established against somatic antigens of L3, recognized this molecule but with different epitope specificities indicated by an additivity index (A.I.) of 83%. The 2 Mc Ab (TD2 and 3A5) belonged to IgG2a and IgM classes, respectively. Combinations of TD2 and 3A5 were used in a sensitive enzyme-linked fluorescent assay (ELFA) for the immunodiagnosis of human angiostrongyliasis. The double-antibody sandwich ELFA method was applied firstly to sera from experimentally infected rats using either TD2 or 3A5 to coat the assay plates. Two fluorescence unit (F.U.) peaks appeared in sera from infected rats collected 18 and 44 days after infection. Specimens from 35 patients were tested, all cerebrospinal fluids (CSF) and most sera (88%) showed positive reactions and the average F.U. of CSF was greater than that of serum.

Passive immunization, toxicity neutralization and the persistence of passive protection in the tiger prawn (Penaeus monodon) were investigated using rabbit antisera to the formalinized extracellular products (ECP) (R alpha ECP) and/or formalinized bacterial cells (R alpha BC) of luminescent Vibrio harveyi strain 820514 originally isolated from diseased tiger prawns. Rabbit antiserum to bovine serum albumin (R alpha BSA) or phosphate-buffered saline (PBS, pH 7.2) both served as controls. The toxicity of ECP to prawns was neutralized by pre-incubation with R alpha ECP. Passive immunization by pre-injection of R alpha BC or R alpha ECP into prawns 3 d in advance protected against a lethal dose challenge of bacteria. To determine the persistence of passive protection by rabbit antiserum in tiger prawns, the R alpha BC, R alpha ECP, R alpha BSA or PBS were injected into prawns. At 10, 17 or 24 d post-immunization, groups of prawns were given a lethal dose challenge of bacteria. The prawns in the two control groups were all killed within the first 2 d following challenge at all three challenge dates. Pre-injection with R alpha BC and R alpha ECP provided total protection for 10 and 17 d, respectively, with all treated prawns surviving for at least 2 weeks post-challenge. This is the first study using mammalian antisera to investigate toxicity neutralization, passive immunization and persistence of passive protection by rabbit antisera in prawns. The results could be useful in future studies on virulence mechanisms and disease control of vibriosis in cultured prawns.

P.-C. LIU, K.-K. LEE AND S.-N. CHEN. 1996. The pathogenicity of six Vibrio harveyi strains in tiger prawn, Penaeus monodon, was studied, using both live bacteria and extracellular products (ECP). The organisms originally isolated from diseased penaeids were more virulent using both live bacteria and ECP (LD50, 4.87–8.65 times 104colony-forming units (cfu) and 1.20–1.51 μg protein g-1body weight) than the two reference strains originally isolated from either sea water (ATCC 25919; LD50, 3.18 times 106cfu and 2.70 μg protein g-1body weight) or diseased Talorchestia sp. (ATCC 14126, 0.418 times 106cfu and 2.34 μg protein g-1body weight). Each strain was reisolated from the haemolymph and the hepatopancreas of moribund prawns following each bacterial challenge. Both the live bacteria and the ECPs of the penaeid isolates exhibited stronger proteolytic (caseinase), phospholipase and haemolytic activities than those of the reference strains. These results indicate that there are differences between penaeid and non-penaeid isolates of V. harveyi in pathogenicity and reveal that proteases, phospholipases, haemolysins or exotoxins might play leading roles in the pathogenicity of V. harveyi in the tiger prawn, Penaeus monodon.

The effects of eyestalk ablation on the acid-base balance of the haemolymph and on the haemocyanin concentration of Penaeus monodon were investigated in a period of 24 hrs. The pH of the haemolymph was low in the shrimps treated bilaterally, intermediate in the shrimps which were unilaterally treated, and high in intact shrimps. The treatment of eyestalk ablation resulted also in a decrease of haemolymph pO2 tension. The pO2 of the haemolymph was low in the shrimps treated bilaterally, intermediate in the shrimps treated unilaterally, and high in the intact shrimps. The pCO2, [HCO- 3] and [HCO- 3 + CO2- 3] of the haemolymph were low in intact shrimps, intermediate in unilaterally ablated shrimps, and high in bilaterally ablated shrimps. Eyestalk ablation resulted in an increase in the haemocyanin concentration. Haemocyanin concentration was high in the shrimps treated bilaterally, intermediate in the shrimps treated unilaterally, and low in the intact shrimps. Therefore, it is concluded that eyestalk ablation of shrimps causes the concentration of oxy-haemocyanin to increase, the pO2 of haemolymph to decrease, and that it also affects the carbonate buffer system.