Branchial Cavity Research Articles

Geographic variation in acid–base balance of the intertidal crustaceanCyclograpsus cinereus(Decapoda, Grapsidae) during air exposure

In intertidal poikilotherms with wide geographic distribution, physiological variations are ubiquitous, due to phenotypic plasticity and/or individual geographic variation. Using the grapsid crab,Cyclograpsus cinereusas a study model, acclimatization differences in respiratory physiology were evaluated among populations along the Chilean coast, covering a latitudinal gradient of about 2000 km. This species inhabits the supratidal zones and, therefore, is subject to constant immersion and emersion periods, producing physiological acidification due to CO2retention, mainly in the branchial cavity. Individuals of six populations were collected along the coastline of Chile and were exposed to air for different time periods in the laboratory. The following parameters were measured: pH, Ca2+, Cl−and haemolymphatic lactate dehydrogenase (LDH) enzyme activity. Populations from lower latitudes were significantly different from those from central and southern Chile, with a higher haemolymphatic pH variation and higher Ca2+level, along with lower levels of Cl−and LDH enzyme activity. This indicates that the populations from lower latitudes, which are subject to higher air temperatures during emersion, have a higher homeostatic capacity during emersion periods than those of intermediate and higher latitudes. This response seems to be determined by genetic bases due to adaptation to the local environment.

First occurrence of Norileca triangulata (Crustacea: Isopoda: Cymothoidae) from Indian marine fishes.

An ectoparasitic isopod, Norileca triangulata was found in the branchial cavity of Sardinella gibbosa at Parangipettai coastal waters. The present findings represent the first record of N. triangulata and herein reported. Until now, this species was distributed from Tanimdao Island, Philippines and from Queensland-Eel Reef, Cape York; Michaelmas Cay, near Cairns and Mooloobah, south-eastern Queensland. The range is here extended and now includes to the Southeast coast of India. The materials examined were deposited at the Annamalai University, India (collection Ravichandran). The parasites has been found on 16 out of 16 specimens of S. gibbosa. The prevalence of N. triangulata on S. gibbosa was 7.5% and mean intensity was 1. The host fish length ranges from 140 to 182mm. It is further confirmed that the parasites were specific in the selection of host S. gibbosa. Previously N. triangulata was reported from two hosts Parexocoetus brachypterus. Females of N. triangulata ranges 12-18mm but not found in males. As summarized comparative characteristic feature of two species of parasitic isopods of Norileca indica and N. triangulata. Host species were captured on pelagic region from the coast of Parangipettai. N. triangulata can be distinguished from N. indica by several characters. A related species N. indica has the head to the anterior, and the abdomen facing outwards, pressed against the gill operculum, positioned ventrally in the gill cavity.

A new record of parasitic isopod for the Indian fauna (Mothocya karobran Bruce, 1986) from Strongylura strongylura in the Pazhayar region, Southeast coast of India.

Cymothoid isopods are permanent ectoparasites of fish. In the present study Strongylura strongylura captured in gillnets from the inshore waters of Pazhayar from January to March-12. Among the 122 Belonidae fishes examined, 16 specimens were parasitized by isopods belonging to the species Mothocya karobran, a new record of this cymothoid isopod for the first time from India. Lowest prevalence occurred in January (10.5%) and the highest in February (15.9%). The infected fishes usually carried one cymothoid per branchial cavity. 12 parasites were found in the left branchial cavity and 4 parasites in the right. The non ovigerous female (18.5-24.7mm) and female ovigerous (20.8-27.4mm) in total length.

<p class="SP315428"><strong>Co-occurrence of the parasitic copepods <em>Acantholochus zairae </em>Morales-Serna & Gómez, 2010 (Poecilostomatoida: Bomolochidae) and <em>Pseudochondracanthus diceraus </em>C. B. Wilson, 1908 (Poecilostomatoida: Chondracanthidae) on the gills of <em>Sphoeroides annulatus </em>(Jenyns) (Pisces: Tetraodontidae)</strong></p>

The spatial distribution of two parasitic copepods, Acantholochus zairae Morales-Serna & Gómez, 2010 (Poecilostomatoida: Bomolochidae) and Pseudochondracanthus diceraus C. B. Wilson, 1908 (Poecilostomatoida: Chondracanthidae), was analyzed on the gills of the bullseye pufferfish Sphoeroides annulatus (Jenyns). A positive association between A. zairae and P. diceraus was observed; however, species coexistence is facilitated because intraspecific aggregation was stronger than interspecific aggregation. Each copepod species was less frequent on the middle arch regions. Pseudochondracanthus diceraus showed a preference for the third gill arch (the innermost), as well as for the dorsal region of the gill arches and the middle zone of the gill filaments. Acantholochus zairae was randomly distributed among gill arches, but showed a preference for the ventral region of the gill arches and the middle zone of the gill filaments. In addition, only A. zairae appeared to be affected by increasing host length. It is possible that water flowing through the branchial cavities of S. annulatus is a major determinant on the distribution of its gill copepods.

First record of Mothocya melanosticta Schioedte and Meinert, 1884 (Isopoda: Cymothoidae) from Egyptian pinecone soldierfish with special reference to its infestation status

Cymothoidae are cosmopolitan, ubiquitous, and nonspecific parasites of fish of different biotopes causing a significant economic loss to fisheries either by killing and stunting or simply by damaging their hosts. This study represents the first record of Mothocya melanosticta from the Red Sea, with a new host record in Myripristis murdjan (pinecone soldierfish), the other resident species of the fish-parasitic isopod family Cymothoidae in Egypt. The recovered Mothocya melanosticta was of moderate body size (17.7 × 8.2 mm) and had a cephalon with widely truncated rostrum, short pleotelson with uropod rami not extending beyond the telson, and the presence of a small rounded protrusion ranging in size from 0.3 to 0.5 mm on the lateral side of pereonite II. The overall prevalence was 31.25% and it was only found in the branchial cavity. The monthly and seasonal variation in infestation is reported.

A new species of Taeniacanthus (Copepoda: Taeniacanthidae) parasitic on two pufferfish species, Marilyna meraukensis and M. darwinii (Teleostei: Tetraodontidae), from Australia

A new species of Taeniacanthidae (Copepoda, Cyclopoida), Taeniacanthus kiemae sp. n., is described based on adult female and male specimens collected from the branchial cavity wall of Marilyna meraukensis (de Beaufort) and M. darwinii (Castelnau) (Teleostei, Tetraodontidae) caught in Australian waters. The new species differs from its congeners by having the following combination of characters in the adult female: (1) maxilla armed with a stout terminal process and two small elements; (2) multiple rows of spinules on the large pectinate process of the antenna; (3) an extremely long and thin maxilliped claw; (4) second exopodal segment of leg 1 with eight setae; (5) third exopodal segment of leg 3 with three spines and four setae; (6) third exopodal segment of leg 4 with three spines and two setae; and (7) each spine on the free exopodal segment of leg 5 with a subterminal flagellum. Taeniacanthus kiemae is the second copepod species reported from M. meraukensis and M. darwinii and the first taeniacanthid species reported from pufferfishes in Australia.

Cardiorespiratory responses to hypoxia in the African catfish, Clarias gariepinus (Burchell 1822), an air-breathing fish

The African catfish, Clarias gariepinus, possesses a pair of suprabranchial chambers located in the dorsal-posterior part of the branchial cavity having extensions from the upper parts of the second and fourth gill arches, forming the arborescent organs. This structure is an air-breathing organ (ABO) and allows aerial breathing (AB). We evaluated its cardiorespiratory responses to aquatic hypoxia. To determine the mode of air-breathing (obligate or accessory), fish had the respiratory frequency (f (R)) monitored and were subjected to normoxic water (PwO(2)=140mmHg) without becoming hyperactive for 30h. During this period, all fish survived without displaying evidences of hyperactivity and maintained unchanged f (R), confirming that this species is a facultative air-breather. Its aquatic O(2) uptake ([Formula: see text]) was maintained constant down to a critical PO(2) (PcO(2)) of 60mmHg, below which [Formula: see text] declined linearly with further reductions of inspired O(2) tension (PiO(2)). Just above the PcO(2) the ventilatory tidal volume (V (T)) increased significantly along with gill ventilation ([Formula: see text]), while f (R) changed little. Consequently, the water convection requirement [Formula: see text] increased steeply. This threshold applied to a cardiac response that included reflex bradycardia. AB was initiated at PiO(2)=140mmHg (normoxia) and air-breathing episodes increased linearly with more severe hypoxia, being significantly higher at PiO(2) tensions below the PcO(2). Air-breathing episodes were accompanied by bradycardia pre air-breath, to tachycardia post air-breath.

Morphological and Biochemical Variations in the Gills of 12 Aquatic Air-Breathing Anabantoid Fish

All fish species in the Anabantoidei suborder are aquatic air-breathing fish. These species have an accessory air-breathing organ, called the labyrinth organ, in the branchial cavity and can engulf air at the surface of the water to assist in gas exchange. It is therefore necessary to examine the extent of gill modification among anabantoid fish species and the potential trade-offs in their function. The experimental hypothesis that we aimed to test is whether anabantoid fishes have both morphological and functional variations in the gills among different species. We examined the gills of 12 species from three families and nine genera of Anabantoidei. Though the sizes of the fourth gill arch in three species of Trichogaster were reduced significantly, not all anabantoid species had morphological and functional variations in the gills. In these three species, the specific enzyme activity and relative protein abundance of Na(+)/K(+)-ATPase were significantly higher in the anterior gills as compared with the posterior gills and the labyrinth organ. The relative abundance of cytosolic carbonic anhydrase, an indicator of gas exchange, was found to be highest in the labyrinth organ. The phylogenetic distribution of the fourth gill's morphological differentiation suggests that these variations are lineage specific, which may imply a phylogenetic influence on gill morphology in anabantoid species.

Quantitative aspects of oxygen and carbon dioxide exchange through the lungs in Ocypode ceratophthalmus (Crustacea: Decapoda) during rest and exercise in water and air

Ghost crabs Ocypode ceratophthalmus were exercised in air and water to measure CO2 and O2 exchange rates using the method of instantaneous measurements of oxygen consumption rate (MO2) where applicable. Average heart rate increased from 100 to nearly 400 pulses per minute after five minutes of exercise on a treadmill at a run rate of 0.133 m s−1. It took less than a minute for oxygen taken up through the lung epithelium from the air inside the branchial cavity to reach the maximal oxygen consumption rate of 26.1 mmol O2 kg−1 h−1. Resting MO2 was 4.06 mmol O2 kg−1 h−1 in air, but decreased to 3.37 mmol O2 kg−1 h−1 in seawater. Radioactive CO2 from injected l-lactate is released linearly by the lung. The percent accumulated 14-CO2 in exhaled air, plotted against time, intersects zero time on the x -axis, indicating rapid gas exchange at the lung surface. The P 50 values for native haemocyanin of 4.89 mm Hg before exercise, and 8.99 mm Hg after exercise, are typical of a high-affinity haemocyanin usually associated with terrestrial crabs. The current notion that Ocypode ceratophthalmus drown when submerged in seawater was not substantiated by our experiments. MO2 in seawater increased from 3.37 mmol O2 kg−1 h−1 for resting crabs to 5.72 mmol O2 kg−1 h−1 during exercise. When submerged by wave-seawater in the natural environment and during exercise in respirometer-seawater O. ceratophthalmus do not swim but, having a specific density of 1.044, float nearly weightless with a minimum of body movements.

Attachments by parasitic lampreys within the branchial cavities of their hosts

Silver Lamprey (Ichthyomyzon unicuspis) in the Wisconsin River attached within the branchial cavity of Paddlefish (Polyodon spathula) significantly more often (6.5% of 1,578 attachments) than would be expected by chance on the basis of its relative surface area (3.7%), with as many as four lampreys found together within the branchial cavity of the same Paddlefish. Similar behavior has occasionally been noted for lampreys in other systems, but the phenomenon may be underreported when the lampreys are concealed from view. As suggested previously for some parasitic trychomycterid catfishes, lampreys in the branchial cavity may benefit from accessing blood under pressure, especially in the ventral aorta. In addition, Silver Lamprey within the branchial cavities of Paddlefish may be relatively protected from any negative effects that might result from Paddlefish breaching.

Nodular gill disease causing proliferative branchitis and mortality in Chinook salmon (Oncorhynchus tshawytscha)

CASE HISTORY: A period of escalating mortality occurred among Chinook salmon (1–5 g) held in freshwater raceways at a commercial culture facility. The mortality rate peaked at 1.5% of the population per day, water temperature was 9–10°C, and water quality had recently deteriorated due to an influx of suspended solids. The affected fish did not respond to several chloramine-T bath treatments (10 ppm for 1 hour). CLINICAL FINDINGS: The dead fish did not exhibit flared opercula typical of infection with bacterial gill disease (BGD) nor did the remaining fish show obvious signs of respiratory distress. Clinical lesions were limited to the gills of the fish, and were consistent with a proliferative branchitis, including substantial hyperplasia and fusion of lamellae. DIAGNOSIS: Numerous angular amoebic organisms (approximately 10 × 8 µm), with a central, large vesicular nucleus and faintly acidophilic cytoplasm, visible on H&E-stained sections, were located on the hyperplastic epithelia of the lamellae, filaments, and remaining lining of the branchial cavity. Morphologically, the amoebae were similar to representatives of the genus Cochliopodia spp. described from North American salmonids, that presented similar lesions and clinical signs; consequently, the disease was diagnosed as nodular gill disease (NGD). CLINICAL RELEVANCE: Grossly, NGD can be mistaken for BGD; the distinction is important because chloramine-T, routinely used in the treatment of BGD, is ineffective for the treatment of NGD. Static formalin baths of 170 ppm (37% formaldehyde) for 1 hour, supplemented with oxygen, may reduce amoebic infections but should be used cautiously as treatment can precipitate mortality in fish with gill disease. Cues for the onset of NGD are not completely understood, although poor water quality and elevations in temperature are likely to exacerbate infections. Similarly, the prevalence of this disease is not accurately known, but it is possible that it may be more common among salmonids in New Zealand than is presently recognised.

Characterization of ion transport in the isolated epipodite of the lobsterHomarus americanus

Unfolded epipodite isolated from American lobsters (Homarus americanus) acclimated to dilute seawater was mounted in an Ussing-type chamber for ion transport studies. The split epipodite is an electrically polarized, one-cell-layer epithelium supported with cuticle. Under open-circuit conditions, the transepithelial potential was -4.2+/-1.0 mV (N=38). In the short-circuited epithelium, the current averaged over all of the preparations was -185.4+/-20.2 A cm(-2) (N=38) with a high conductance of 55.2+/-11.4 mS cm(-2) (N=38), typical for a leaky epithelium. The Na:Cl absorptive flux ratio was 1:1.6; ion substitution experiments indicated that the transport of Na+ and Cl- is coupled. Basolateral application of the Cl- channel blockers 5-nitro-2-(3-phenylpropylamino) benzoate (NPPB) and niflumic acid (NFA) dose-dependently inhibited short-circuit current (ISC). Secretory K+ (Rb+) fluxes exceeded influxes and were inhibited by the Na+/K+-ATPase inhibitor ouabain and the K+ channel blocker cesium. Western blot analysis showed that Na+/K+-ATPase alpha-subunit protein was more highly expressed in the epipodite of lobsters acclimated to 20 p.p.t. compared with animals acclimated to seawater (34 p.p.t.). 3-Isobutyl-1-methyl-xanthine (IBMX) stimulated a negative ISC and enhanced apical secretory K+ flux. Basolateral application of NPPB inhibited JRbB-->A fluxes, suggesting the interaction of K+ channels with NPPB-sensitive Cl- channels. The results are summarized in a transport model, suggesting apical Na+/K+/2Cl- co-transport, a dominant apical K+-secreting channel and basolaterally located Cl- and K+ channels. This study represents the first comprehensive characterization of ion transport processes across the lobster epipodite epithelium and indeed in any tissue within the branchial cavity of the American lobster.

Gill morphometrics in relation to gas transfer and ram ventilation in high‐energy demand teleosts: Scombrids and billfishes

This comparative study of the gill morphometrics in scombrids (tunas, bonitos, and mackerels) and billfishes (marlins, swordfish) examines features of gill design related to high rates of gas transfer and the high-pressure branchial flow associated with fast, continuous swimming. Tunas have the largest relative gill surface areas of any fish group, and although the gill areas of non-tuna scombrids and billfishes are smaller than those of tunas, they are also disproportionally larger than those of most other teleosts. The morphometric features contributing to the large gill surface areas of these high-energy demand teleosts include: 1) a relative increase in the number and length of gill filaments that have, 2) a high lamellar frequency (i.e., the number of lamellae per length of filament), and 3) lamellae that are long and low in profile (height), which allows a greater number of filaments to be tightly packed into the branchial cavity. Augmentation of gill area through these morphometric changes represents a departure from the general mechanism of area enhancement utilized by most teleosts, which lengthen filaments and increase the size of the lamellae. The gill design of scombrids and billfishes reflects the combined requirements for ram ventilation and elevated energetic demands. The high lamellar frequencies and long lamellae increase branchial resistance to water flow which slows and streamlines the ram ventilatory stream. In general, scombrid and billfish gill surface areas correlate with metabolic requirements and this character may serve to predict the energetic demands of fish species for which direct measurement is not possible. The branching of the gill filaments documented for the swordfish in this study appears to increase its gill surface area above that of other billfishes and may allow it to penetrate oxygen-poor waters at depth.

Relationships between the diets and characteristics of the dentition, buccal glands and velar tentacles of the adults of the parasitic species of lamprey

AbstractThe intestinal contents of adults of 12 of the 18 species of parasitic lampreys were examined microscopically and tested for blood to determine whether a species fed mainly on blood, flesh or blood and flesh. The diets of each species are shown to be related to characteristics of their dentition, buccal glands and velar tentacles. The trends exhibited by those relationships were used to hypothesize as to the diets of those six species for which there were anatomical but not dietary data. The dentition aids the suctorial disc in attaching the lamprey to its host and removing host material, while velar tentacles prevent material entering the branchial cavity and buccal glands produce lamphredin that has anticoagulant and lytic properties. In blood feeders, such as Petromyzon marinus and Mordacia species, the w‐shaped transverse lingual lamina and hook‐shaped longitudinal laminae bear numerous, fine cusps, which are ideal for rasping a hole in the host. In contrast, in flesh feeders, such as Lampetra fluviatilis and Geotria australis, the transverse lingual lamina is u shaped and the longitudinal laminae are straighter and possess at least one stout cusp, thereby facilitating the removal of host flesh through gouging. The buccal glands are generally larger in blood feeders than flesh feeders, presumably reflecting a need to produce anticoagulant continuously. Each velar tentacle contains a central cartilaginous rod, surrounded by a space which, during feeding, becomes engorged with blood and thus more rigid. They are small (≤1 mm long) and few (2–6) in blood feeders and large (typically ≥2 mm long) and numerous (3–42) in flesh feeders, which, in particular, require a mechanism for preventing solid material entering the branchial pouches and thus potentially clogging the gills. On the basis of recent cladistic analysis, blood feeding is ancestral to flesh feeding in Northern Hemisphere lampreys (Petromyzontidae).

ASPECTS OF BRANCHIAL PARASITISM IN BARBUS MERIDIONALIS PETENYI HECKEL, 1847(TELEOSTEI: CYPRINIDAE)

The present paper aims to analyze some ecological a spects of the branchial microhabitat in Mediterranean barbell ( Barbus meridionalis petenyi Heckel, 1847). In the autumn of 2006, we sampled 24 specimens belonging to this cyprinid by electrofish ing from the SomeBasin. The parameters calculated for the infestation with Paradiplozoon tisae Khotenovski, 1982, were: prevalence, mean intensit y and mean abundance. Regarding the monogeneans fixing sites, most of the m manifested obvious preference for: first branchia l arch, internal hemibranch, median zone. The conclusions were argued by using the Student's t test, which als o demonstrated that parasite distribution in the righ t branchial cavity was not significantly different from the left branchial cavity (p>0.05). Also, we discussed the r elationship between host total length and the inten sity of infection. This is the first record for Paradiplozoon tisae in the Romanian fauna.

A New Species of the Roughy Genus Hoplostethus (Trachichthyidae) off Northwestern Australia

Gomon, M.F. 2008. A New Species of the Roughy Genus Hoplostethus (Trachichthyidae) off North-western Australia. Memoirs of Museum Victoria 65: 189–194. Hoplostethus ravurictus n.sp. is described from a large series collected at continental slope depths in tropical latitudes off North-western Australia. Its description brings the number of documented Australian species of the subgenus Hoplostethus (Hoplostethus) to four, the three previously recognised species primarily occurring in subtropical and temperate waters of the south. The new species is easily distinguished by the rather pale pigmentation in its buccal and branchial cavities, 13–16 (rarely 10–12 or 17–20) abdominal scutes and fully scaled isthmus. Its characters do not support a particularly close relationship with any of its recognised congeners.

Mikrocja – izolowane zaburzenie rozwojowe narządu słuchu czy zespół wad?

Congenital malformations of the external ear are relatively rare, however gradual increase in their frequency has been observed in the last years. These defects can occur as isolated congenital malformations, but they can coexist with congenital malformations of facial skeleton and also with congenital defects of distant organs. The purpose of this study was to determine coexisting facial skeleton defects and congenital defects of distant organs in a group of patients with unilateral or bilateral congenital malformations of the external ear. 37 patients age 1 to 30 [mean age 12.4 years] with anotia, microtia or aplasia of external ear canal were part of this study. In 17 examined patients [46.0% of all examined persons] microtia could be treated as an isolated malformation, however hypoplasia of other elements formed from branchial arches, including mandibula, cheek or oral cavity, was found in 15 examined patients [40.5%]. In 11 [29.7%] patients congenital malformations of the external ear were found together with the congenital defects of distant organs (kidney, heart, muscular and skeletal system), and in two patients [5.4%] the defects involved even two different distant organs. Defects of the distant organs were found more frequently in patients with bilateral malformations of the external ear than in patients with unilateral ear malformation. In authors opinion each patient, even with seemingly isolated microtia, should be closely examined in order to exclude probable congenital defects of the distant organs.

Geochemical energy sources for microbial primary production in the environment of hydrothermal vent shrimps

At deep-sea hydrothermal vents, dense invertebrate communities prevail along chemoclines where the relaxation of redox-disequilibria sustains chemolithoautotrophic microbial CO2-fixation. At the Mid-Atlantic Ridge, swarms of thousands of Rimicaris exoculata shrimps thus assemble along the turbulent mixing interface between the hydrothermal fluid and oxygenated seawater. It was suggested that this environment provides ideal conditions for growth to the abundant chemosynthetic microbial epiflora that colonizes the shrimps' branchial cavity. Sulfide has long been considered as the prime electron donor used by the epibionts but, the oxidation of iron has recently been hypothesized as an alternative pathway for the iron-rich Rainbow site. In order to examine the potential energy sources for microbial primary production within the swarms at Rainbow, the chemical conditions along the mixing gradient have been modeled from field data. This model provides a basis for the quantitative comparison of energy-budgets available for chemolithoautotrophic primary production based on different oxidative pathways (e.g.: oxidation of sulfide-iron II-methane and hydrogen by oxygen). A comparison was proposed for TAG, another hydrothermal vent field at the mid-Atlantic Ridge which is characterized by the presence of similar swarms. Although the narrow temperature range of the shrimp environment is similar at both sites, their chemically contrasted environments suggest different metabolic pathways would benefit from the highest energy budgets. While sulfide oxidation is confirmed to be the energetically most favorable pathway at TAG, an original biogeochemical context is suggested for Rainbow. Here, the highest energy could be derived from iron oxidation. At this site, the oxidation of hydrogen possibly constitutes another dominant energy source, but this hypothesis still needs to be constrained by kinetic studies. Methane and sulfide appears as minor energy sources in the environment of shrimps. A wider and original diversity of the metabolic pathways involved in the microbial epibiosis can be expected at Rainbow in comparison to TAG.

Immobilization antibodies of tiger puffer Takifugu rubripes induced by i.p. injection against monogenean Heterobothrium okamotoi oncomiracidia do not prevent the infection

We examined whether infection by the monogenean Heterobothrium okamotoi induces production of specific antibodies against oncomiracidia and their cilia, larvae on the gills, and adults on the branchial cavity wall of tiger puffer Takifugu rubripes. We also investigated whether specific antibody production participates in acquired protection against H. okamotoi. Sera from persistently infected fish immobilized H. okamotoi oncomiracidia 89 days after exposure and antibody levels (measured by enzyme-linked immunosorbent assays) in the sera against oncomiracidia and their cilia increased compared with sera from control (naïve) fish. Antibody levels in these sera against the larvae and adult stages did not increase. The number of H. okamotoi on persistently infected fish was significantly lower than for control fish (P<0.05) when persistently infected fish and control fish were exposed to oncomiracidia in the same tank. Thus tiger puffer produced specific antibodies against oncomiracidia and their cilia, and acquired partial protection against H. okamotoi. Intraperitoneal injection of proteins of sonicated oncomiracidia or their cilia with an adjuvant also produced oncomiracidium agglutination antibodies in sera from tiger puffer; the antibody levels in these sera against oncomiracidia and their cilia increased compared with sera from control fish (injection of BSA with an adjuvant) at 14, 44, and 75 days after the booster immunization. However, in a parasite challenge at 54-58 days after the booster immunization, the infection levels of fish immunized with parasites of sonicated oncomiracidia or their cilia were the same as the control fish. Western blot showed that sera from persistently infected fish and fish immunized with sonicated oncomiracidia or their cilia recognized similar antigenic bands, suggesting that tiger puffer tends to react against these antigens compared with other antigens. These results indicated that specific antibodies against these cilia and oncomiracidia induced by i.p. injection do not prevent H. okamotoi infection.

Redescription of Brasilochondria riograndensis (Copepoda, Chondracanthidae) parasitic on flounder, Paralichthys orbignyanus (Actinopterygii, Pleuronectiformes) from South American Atlantic waters

AbstractBrasilochondria riograndensis Thatcher et Pereira, 2004 (Copepoda, Chondracanthidae) is redescribed based on newly collected material from the branchial cavity of flounder, Paralichthys orbignyanus (Valenciennes, 1842), from the coasts of Buenos Aires Province, Argentina. A number of details were overlooked and some appendages were misidentified in original description and are included herein. These are: the distribution and the number of setae and spines in the antennule, the armature and segmentation of mandible, maxillule, maxilla, and maxilliped, pedigerous segments and genitoabdomen, in both, females and males. Moreover, the geographical distribution of this parasite species is broadened.