PERKEMBANGAN JUMLAH EKTOPARASIT Pseudorhabdosynochus spp. PADA INSANG KERAPU HIBRIDA CANTIK (Epinephelus fuscoguttatus x E. polyphekadion) MELALUI METODE KOHABITASI

Genus Pseudorhabdosynocus merupakan Monogenea yang sering menginfeksi ikan kerapu. Pengaruh perbedaan jarak antara ikan sakit dengan ikan sehat terhadap perkembangan jumlah Pseudorhabdosynochus spp. pada ikan kerapu hibrida “cantik” dipelajari dalam penelitian ini melalui metode kohabitasi. Kohabitasi dilakukan dengan dua metode yaitu (a) menempatkan lima ekor ikan sakit ke dalam keranjang dengan jarak 25 cm dari dasar bak, dan (b) menempatkan lima ekor ikan sakit ke dalam keranjang dengan jarak 10 cm dari dasar bak. Kedua keranjang tersebut diapungkan ke dalam bak plastik berbeda dengan volume 100 L air laut (33 ppt) yang masing-masing telah berisi 30 ekor ikan kerapu hibrida “cantik” sehat. Masing-masing lima ekor ikan dari kedua metode kohabitasi diambil pada hari ke-2, 4, 6, 8, 10, dan 15 pemeliharaan. Hasil penelitian menunjukkan bahwa infeksi buatan menggunakan metode kohabitasi (b) lebih cepat menyebarkan Pseudorhabdosynochus spp. dari ikan sakit ke ikan sehat dibandingkan dengan metode kohabitasi (a). Perkembangan populasi Pseudorhabdosynochus spp. dan telurnya pada metode kohabitasi (b) lebih tinggi yaitu 1.495 ± 206,3 ekor/ikan dan 18,6 ± 3,8 telur/ikan dibandingkan dengan metode kohabitasi (a) yaitu 163,2 ± 16,3 ekor/ikan dan 3,8 ± 0,7 telur/ikan pasca 15 hari kohabitasi. Secara histopatologi, lamela insang yang terinfeksi Pseudorhabdosynochus spp. menunjukkan adanya hyperplasia epitel sel filamen insang yang menimbulkan fusi filamen. Kerusakan filamen di hampir semua lamela insang menyebabkan terganggunya sistem pernapasan ikan kerapu. Hasil tersebut dapat disimpulkan bahwa penyebaran Pseudorhabdosynochus spp. semakin cepat dengan semakin dekat jarak kontak antara ikan sakit dengan ikan sehat.Pseudorhabdosynocus is a genus of Monogenea that frequently infect grouper fish. This study aimed to observe the changes of density patterns of Pseudorhabdosynochus spp. in hybrid grouper gill through cohabitation. Two cohabitation methods were applied to understand the effects of distance between sick and healthy fish in terms of parasite infection. The cohabitation methos were arranged as follows: (a) five fish infected with Pseudorhabdosynochus spp. were placed into a basket at a distance of 25 cm from the bottom of the tank, and (b) five fish infected with Pseudorhabdosynochus spp. were placed into a basket at a distance of 10 cm from the bottom of the tank. The two baskets were floated into different plastic tanks of 100 L of seawater (33 ppt), each of which contained 30 healthy hybrid groupers. Each of the five fish from the two cohabitation methods was sampled on day 2, 4, 6, 8, 10, and 15 after cohabitation. The results showed that the spread of Pseudorhabdosynochus spp. from sick fish to healthy fish with the cohabitation method b was faster than the cohabitation method a. The development number of Pseudorhabdosynochus spp. and its eggs in the cohabitation method b were higher, reaching 1,495 ± 206.3 parasite/fish and 18.6 ± 3.8 eggs/fish than the cohabitation method a, 163.2 ± 16.3 parasite/fish and 3.8 ± 0.7 eggs/fish after 15 days of cohabitation. Histopathologically, gill lamella infected with Pseudorhabdosynochus spp. showed the presence of epithelial hyperplasia of gill filament cells causing fusion. Damage of the gill filament in all of gill lamella has caused disruption of the grouper breathing system. From these findings, it can be concluded that the spread of Pseudorhabdosynochus spp. was faster if the distance of direct contact between sick and healthy fish was closer.

Identifikasi Dan Prevalensi Ektoparasit Ikan Kerapu Lumpur (Epinephelus tauvina) Pada Keramba Jaring Apung Di Kuala Langsa

Greasy grouper (Epinephelus tauvina) is one type of marine fish that has economic value and can be developed into a promising cultivation commodity. The purpose of this research is to find Types of parasites and prevalence rates of ectoparasite in Greasy grouper (Epinephelus tauvina) on floating net cages in Kuala Langsa. The research method was conducted using a survey method. Sample taken by purposive sampling, amounting to 20 Greasy grouper (Epinephelus tauvina) with a size of 20-25cm and were observed at Laboratory Faculty of Agriculture, Samudra University. Fish body organs were observed including all parts of the fins, mucus, gills, then identification using microscopic and macroscopic methods. The results obtained were ectoparasites infecting Greasy grouper (Epinephelus tauvina) only one species from the genus Dactylogyrus which was found mostly in floating net cages cultivation in Kuala Langsa. These ectoparasite were found in the gill lamella Greasy grouper (Epinephelus tauvina), with the overall sample prevalence rate at 50% and the attack rate classified as “very frequent”.

First Evidence of Carp Edema Virus Infection of Koi Cyprinus carpio in Chiang Mai Province, Thailand

The presence of carp edema virus (CEV) was confirmed in imported ornamental koi in Chiang Mai province, Thailand. The koi showed lethargy, loss of swimming activity, were lying at the bottom of the pond, and gasping at the water’s surface. Some clinical signs such as skin hemorrhages and ulcers, swelling of the primary gill lamella, and necrosis of gill tissue, presented. Clinical examination showed co-infection by opportunistic pathogens including Dactylogyrus sp., Gyrodactylus sp. and Saprolegnia sp. on the skin and gills. Histopathologically, the gill of infected fish showed severe necrosis of epithelial cells and infiltrating of eosinophilic granular cells. Electron microscope examination detected few numbers of virions were present in the cytoplasm of gill tissue which showed an electron dense core with surface membranes worn by surface globular units. Molecular detection of CEV DNA from gill samples of fish was performed by polymerase chain reaction (PCR) and confirmed by nested-PCR. Phylogenetic analyses revealed that CEV isolate had 99.8% homology with the CEV isolated from South Korea (KY946715) and Germany (KY550420), and was assigned to genogroup IIa. In conclusion, this report confirmed the presence of CEV infection of koi Cyprinus carpio in Chiang Mai province, Thailand using pathological and molecular approaches.

DERAJAT INFESTASI Trichodina sp. PADA LELE DUMBO (Clarias gariepinus) DI EMPAT KOLAM PEMBUDIDAYAAN DI KABUPATEN SUMENEP

This research was aimed to find out the prevalence and degree of infection Trichodiniasis on the Dumbo catfish (Clarias gariepinus) in four ponds cultivation of Sumenep Regency, East Java. The total of 200 samples of Dumbo catfish were from four cultivation ponds to be examined in the Parasitology laboratory of the Faculty of Veterinary Medicine, Univercity Wijaya Kusuma Surabaya. The examination was carried out by means of scraping mucus as well as taking the gill Lamella and observed under the microscope with 100x and 400x magnification. The results showed that the highest level of Trichodiniasis prevalence was in the cultivation pool C (64%) With the degree of infection 5.62 individual parasites/fishes including the category of severe infections while in the pond cultivation A (28%) With the degree of infection 1.86 individual parasitic/fish, cultivation pool B (30%) With the degree of infection 2.46 individual parasites/fishes and the cultivation pond D (48%) With an infection degree 3.02 individual parasites/fishes including a category of mild infections. So using Uji-T can be known results of cases of Trichodiniasis that attacked Dumbo catfish (clarias gariepinus) on four pools of cultivation in Sumenep Regency, East Java showed a very noticeable difference.

A depth cline in deep-sea octopods (Cephalopoda: Graneledone) in the northeast Pacific Ocean

Bathyal octopods of the genus Graneledone Joubin, 1918 in the northeast Pacific differ dramatically in skin texture. To test the hypothesis that these differences are associated with geography, we quantified the skin warts and tubercles of 50 specimens collected between 36°N and 46°N from 1116 to 2850 m depth. Using Principal Component Analysis (PCA), we analyzed the numbers of mantle and head warts, mantle and web tubercles, arm suckers, and inner and outer gill lamellae, adding head width as a size proxy. We used Canonical Correlation Analysis to explicitly test the relationship of morphology to depth and latitude. Sequences of 12S rRNA, 16S rRNA, and COI genes from 12 individuals quantified genetic divergence. PCA revealed correlated variation in head width, arm suckers, and gill lamella counts opposed by skin texture on PC1; PC2 showed correlated variation in skin texture opposed by gill lamella counts. Both components correlate with depth and latitude but, as most shallow specimens came from southern localities, the correlation with latitude may be artefactual. is relationship is corroborated by the canonical correlations. Octopods from greater depths are smaller than those from shallower depths, have rougher skin texture, and fewer suckers and gill lamellae. Clades of shallow and deep octopods show 0.8% genetic divergence in COI (Kimura two-parameter distance), not inconsistent with intraspecific differentiation. We conclude that the variation is likely clinal with depth. The observed morphological differences may result from differences in food availability and oxygen saturation with depth.

Antagonistic Effects of Sublethal Concentrations of Certain Mixtures of Metal Oxide Nanoparticles and the Bulk (Al2O3, CuO, and SiO2) on Gill Histology in Clarias gariepinus

Background. The effect of nanoparticles (NPs) on aquatic environments is poorly studied. Aim. This study evaluates the toxicity of joint effects of these different metal nanoparticles and their bulk in mixtures (Al2O3, CuO, and SiO2) on fish using histological biomarker. Materials and Methods. The bulk and nano sizes of three salts (Al2O3, CuO, and SiO2) were used. Nanosizes ranged from 25 nm to 100 nm. The juvenile fishes of Clarias gariepinus (mean Length: 12.3 ± 3.5 cm; mean weight: 18.52 ± 6.41 g) were used for the acute and chronic toxicity tests. They were exposed to 7 mg/L each of the bulk and nano sizes of the three metallic oxides either singly or in mixtures for 28 days. The basis for the sublethal concentration was that the 96 hr acute toxicity of the varied sizes of the three metallic oxides was nontoxic up to the concentrations of 100 mg/L with no significant mortality at the highest exposure concentrations. The gills were collected for histopathology. Results. Of the three metal oxide nanoparticles, SiO was the most toxic, with histopathological alteration index (HAI) of 20.0, followed by nano-CuO (HAI, 10.0) and nano-Al2O3 (HAI, 2.0). In single exposure, the gill alterations include high frequencies of erosion of gill lamella (EGL), hypertrophy (HPT), oedema (OD), and necrosis (N). Less damage was observed at the combination of the metal oxide nanoparticles of SiO + Al2O3, SiO + CuO and SiO + Al2O3 + CuO in equal (1 : 1—HAI, 2 and 6; 1 : 1 : 1—HAI, 6) and unequal ratios (1 : 2—HAI, 16 and 6; 2 : 1—HAI, 8 and 6). Similarly, all bulk combinations were also antagonistic except for the equal ratio of bulk CuO (HAI, 20) and bulk Al2O3 (HAI, 10) that gave additive effect with HAI of 32. Conclusion. The joint actions of nano Al2O3 and CuO with SiO produced a low toxic effect, unlike the high toxicity of their single trials; this also indicates that nano Al2O3 and CuO are antagonists. Similarly, among the bulk metal oxides (SiO, Al2O3, and CuO), CuO was the most toxic. Bulk SiO and Al2O3 are antagonistic on the effects of CuO on the fish gill. There is need to properly document the ecological implications of nanoparticles in the aquatic environment.

Histo-toxicity of Corexit 9500 Dispersant on Gill and Liver of Clarias gariepinus (Burchell 1822)

The aim of this study was to assess the chronic toxicity of Corexit 9500 on histology of liver and gill of juveniles of Clarias gariepinus. Range finding tests were conducted over a 96-hr period after acclimatization of the test organisms in the C.P. Powell laboratory in the University of Port Harcourt, Nigeria. The test organisms 10/treatment were exposed to the following concentrations of Corexit 9500; 0.00 ml/L, 0.0125 ml/L, 0.025 ml/L and 0.05 ml/L in triplicate. Liver and gill were excised from fish every week for histological assay using standard methods. The LC50 at 96 hrs was 0.115 ml/L. The growth in length and weight of C. gariepinus was significantly higher in the control than the test treatments (p<0.05). Hyperplasias, necrosis of epithelial cells, inflammation of the secondary gill lamella and hypertrophic primary gill lamella were observed in the exposed gills. Hepatic lesions in the liver tissues of the fishes exposed to Corexit 9500 were characterized by hyperplasia, narrowing of the central vein and vacoulations. The alterations observed in the liver and gill tissues indicated that Corexit 9500 may have interfered with transamination and metabolic processes, with the possibility of affecting the physiological functions of the fish in an aquatic environment.

INTENSITAS PARASIT INSANG (TREMATODA MONOGENEA: Pseudorhabdosynochus sp.) PADA IKAN KERAPU HIBRIDA MELALUI INFEKSI BUATAN

Infeksi trematoda monogenea: Pseudorhabdosynochus sp. dapat menyebabkan kematian massal pada ikan kerapu. Prevalensi infeksi trematoda ini mencapai 100%, namun intensitasnya hingga menimbulkan gejala klinis dan kematian ikan belum diketahui. Tujuan dari penelitian ini adalah untuk mengetahui intensitas parasit insang (Pseudorhabdosynochus sp.) pada ikan kerapu hibrida “cantik” melalui infeksi buatan. Ikan uji direndam dalam air tawar dengan 100 mg/L formalin selama satu jam sebelum digunakan. Infeksi buatan dilakukan melalui (A) kohabitasi antara ikan sehat dengan ikan sakit dan (B) penempelan potongan lamella insang ikan yang terinfeksi parasit ke lamella insang ikan sehat. Pada perlakuan (A) sebanyak lima ekor ikan uji dipelihara bersama dengan dua ekor ikan sakit selama 3-4 hari, sedangkan perlakuan (B) penempelan lamella insang ikan sakit (1 g lamella insang/ikan) dilakukan pada lima ekor ikan uji selama lima menit. Masing-masing perlakuan diulang tiga kali. Pada Kontrol kepadatan ikan uji sehat sebanyak enam ekor dan lima ekor. Wadah yang digunakan berupa bak plastik volume 100 L. Pengamatan intensitas parasit dan telurnya pada setiap lamella insang bagian kanan dan kiri dari lima ekor ikan uji dilakukan selama tiga minggu dengan interval waktu satu minggu. Hasil pengamatan menunjukkan bahwa kohabitasi antara ikan sehat dan ikan sakit menyebabkan intensitas parasit Pseudorhabdosynochus sp. dan telurnya lebih tinggi dibandingkan dengan penempelan lamella insang. Pada kontrol, Pseudorhabdosynochus sp. maupun telurnya tidak ditemukan selama tiga minggu pemeliharaan. Hasil ini menunjukkan penyebaran Pseudorhabdosynochus sp. dari ikan sakit ke ikan sehat lebih cepat dibandingkan dengan penempelan dari lamella insang ikan sakit.Monogenetic trematode (Pseudorhabdosynochus sp.) infection often leads to mass mortality in groupers, with prevalency reaching 100%. However, the intensity of this parasite to infect grouper fish has yet to be reported. The purpose of this research was to study the intensity of Pseudorhabdosynochus sp. in hybrid grouper “cantik” through experimental infection. The test fish were soaked with 100 mg/L of formalin in fresh water before used. The experimental infections were performed through: (A) cohabitation between healthy fish with sick fish and (B) infection with attached of gills lamella of sick fish to gill lamella of healthy fish. In treatment (A), a total of five test fish were cohabited with two sick fish for 3-4 days, while in treatment (B), attachment of gills lamella (1 g/fish) was done on five test fish for five minutes. Each treatment was repeated for three times. Six and five test fish were maintened as controls. The containers used were 100 L plastic tanks volume. Observation of intensity of the parasite infection and its egg production in each lamella along the right and left gills of five fish were conducted for three weeks with one week intervals. The result showed that the cohabitation between healthy and sick fish caused an increase in total of Pseudorhabdosynochus sp. and its eggs compared with the attachment of chopped-gills. In the control group, Pseudorhabdosynochus sp. and its eggs were not found for three weeks. These results indicate the spread of Pseudorhabdosynochus sp. from the sick fish to the healthy is fish faster than the attachment of gill lamella from the sick fish.

Supplementary studies on Myxobolus tsangwuensis Chen, 1954 (Myxozoa: Myxosporea) infecting the gills of common carp Cyprinus carpio (L.): molecular and histological data

Myxobolus tsangwuensis Chen, 1954 is a common parasite infecting the gills of common carp Cyprinus carpio (L.). It was described simply in the original description and its molecular data was absent, which makes the accurate diagnosis challenging. Here we supplemented its description based on the morphological, histological and molecular data. It was characterized by the presence of small round or ellipsoidal plasmodia in the gills of host and histology showed the plasmodia developed in the capillary network of the gill lamella. Mature spores of M. tsangwuensis were ellipsodal in frontal view and lemon shaped in lateral view, averaging 11.2 ± 0.7 (10.2–12.5) μm × 9.3 ± 0.3 (8.5–10.0) μm × 6.2 ± 0.4 (5.5–7.0) μm. Spores valves were symmetrical and smooth. Occasionally, a small intercapsular appendix was observed. Two polar capsules were pyriform with different sizes, measuring 5.0 ± 0.2 (4.4–5.3) μm × 3.1 ± 0.1 (2.9–3.5) μm and 3.9 ± 0.2 (3.4–4.3) μm × 2.5 ± 0.2 (2.0–2.8) μm, respectively. Polar filaments coiled five to seven turns in large polar capsule and three to four turns in the small polar capsule. Some spores were surrounded by the mucous envelope that was not recorded in the original description. Molecular analysis revealed that the present SSU rDNA sequences did not match any available sequences in GenBank and phylogenetic analysis showed M. tsangwuensis was sister to M. basilamellaris and M. musseliusae.