Search

Cantang grouper (Epinephelus sp.) is a fish with a high economic value and has been widely cultivated. VNN disase, caused by Betanodavirus infection, can lead to mass mortality of cantang grouper. Precautions considered effective in preventing Viral nervous necrosis (VNN) disease include vaccination. This study aimed to determine the effect of administering recombinant Chlorella vulgaris protein nanovaccine based on chitosan hybrid nanoparticles in increasing the immune response of cantang grouper infected with VNN. The study consisted of five treatments: K+ (cantang grouper infected with VNN), K- (healthy cantang grouper), T1 (healthy cantang grouper given 33 µl of nanovaccine and then challenged with VNN), T2 (healthy cantang grouper given 66 µl of nanovaccine and then tested with a VNN challenge), and T3 (healthy cantang grouper given 112 µl of nanovaccine and then tested with a VNN challenge). The parameters observed were haematology, nanovaccine Relative percent survival (RPS), and Survival rate (SR) levels. The study results showed that administering the nanovaccine increased the immune response of the fish, as indicated by an increase in haematology response, RPS, and SR in cantang grouper compared to the treatment without nanovaccine administration. The best dose of nanovaccine in this study is 33 µl. [ABSTRACT FROM AUTHOR]

Highlight Research • Feeding of maggot flour formulations to koi carp infected with tarda • Active compounds contained in maggot • Clinical symptoms of koi carp infected with tarda • Damage to the muscle and gill tissue of koi carp infected with E. tarda Abstract The problem that fishes farmers often face is disease. Maggot contains a high protein which ranges from 41-42%. Besides that, maggot also has a good effect on increasing the body resistance of fish. While the maggot provision fulfills nutritional need, it's also expected to boost immunity against bacterial disease. One of which is Edwardsiella tarda, known to infect koi carp (Cyprinus carpio). Feeding of maggot flour at different doses, namely A (25%), B (50%), C (75%), and D (100%) was carried out to determine its effect on the histopathology of the muscles and gills of C. carpio infected with E. tarda. Water quality during the study obtained an average value, namely the temperature ranging from 26-27.5℃, pH 6.5-8.1, and DO 5.2-8 mg/L. Fish infected with E. tarda showed several clinical symptoms, including rapid operculum movement, irregular and slow swimming, and bleeding on the skin. The results of the histopathological analysis showed that in muscle and gill tissue, treatment C (75%) showed the lowest damage value among other treatments with an average score of necrosis 0.93, hyaline degeneration 1.33, and Edema 1.27. Average score of gill tissue damage was 0.9 fusion, 1.3 congestion, 0.9 hyperplasia. Based on this, the provision of maggot flour can be used to prevent infection of E. tarda against C. carpio.

Indonesia become a maritime country with large of ocean area and beach line with marine species diversity reaches 37% of the world’s fish. This makes Indonesia have aquaculture potential that supported by an appropriate climate. However, the challenge of viral diseases caused by Infectious Spleen and Kidney Necrosis Virus (ISKNV) and Viral Nervous Necrosis (VNN) would hamper marine aquaculture and causing huge economic losses. Therefore, it is necessary to carry out early detection methods that are efficient, fast, precise and accurate to identifying these viral disease. Here we developed a multiplex-PCR (mPCR) a method that can detect simultaneously of the ISKNV and VNN. The results of this method showed high sensitivity and specificity by using MCP and CP gene target primers to detect ISKNV and VNN, respectively. From a total of 353 samples of seawater fish examined by mPCR, positive results following of single infection of ISKNV and VNN were 14 and 2, respectively. We also found that 18 grouper fish was co-infection with these viruses. From these results, it shows that the mPCR method developed has efficiency, faster and high accuracy. This founding was possible to be applied in laboratory testing or early detection system in the field for ISKNV and VNN.

Highlight Research: • It has been found that many fish died with wounds from farmers in Blitar, Indonesia. • The mucosal smear test from mucosal gills of C. carpio infected with Myxobolus. • In the blood smear test of C. carpio, there was no myxobolus found in the blood. • In gill organ testing using SEM that Myxobolus is found in gills (C. carpio). • The shape of Myxobolus resembles an imperfect ball with a hollow in the middle. Abstract The biggest problem that is often considered to be an obstacle to Common carp culture is the emergence of disease attacks. One type of disease that often attacks the seeds of Cyprinus carpio is Myxobolus (a systemic parasite that can cause harm to fish farming). The aim of this study was to determine the molecular expression through the smear test on C. carpio gills, to determine the image of the gill organs of C. carpio using the SEM test, and to determine the description of the spores of Myxobolus sp. Data were analyzed using descriptive methods. Descriptive method used was comparative descriptive comparing molecular expression in the test of gill mucosal smear of fish using a light microscope and gill organ testing using Scanning Electron Microscope (SEM) on C. carpio infected by Myxobolus sp. In this study, the results showed that in C. carpio infected with true Myxobolus found the presence of Myxobolus in the mucosal smear test and SEM test on gill tissue, but not found in the blood smear test.

Kematian ikan akibat serangan parasit Argulus dikarenakan ikan mengalami emasiasi sehingga dapat menurunkan sistem kekebalan tubuh ikan, selain itu munculnya luka pada kulit ikan akan dimanfaatkan sebagai port of entry bagi agen infeksi sekunder seperti jamur, bakteri dan virus. Pengendalian penyakit argulosis dengan bahan kimia yang tidak tepat dosis dapat mencemari lingkungan, sehingga perlu dicari alternatif bahan kimia yang aman terhadap lingkungan, yaitu abate. Tujuan dari penelitian ini yaitu untuk mengetahui efektivitas perendaman abate untuk menurunkan derajat infestasi dan merusak organ parasit Argulus yang menginfestasi ikan mas (Cyprinus carpio). Perlakuan yang diberikan terdiri dari lima perlakuan dengan empat kali ulangan yaitu pemberian abate dengan konsentrasi 0 ppm (kontrol), 25 ppm, 50 ppm, 75 ppm, dan 100 ppm yang direndam selama 30 menit. Parameter yang diamati pada penelitian ini yaitu derajat infestasi Argulus yang menempel pada ikan mas, kerusakan organ Argulus dan nilai kualitas air pada awal dan akhir perendaman sebagai parameter pendukung. Data derajat infestasi Argulus pada ikan mas dianalisis secara statistik menggunakan ANOVA 5% yang dilanjutkan dengan uji DMRT 5% sedangkan kerusakan organ Argulus dianalisis secara deskriptif dan disajikan dalam bentuk gambar dan tabel serta dihubungkan dengan parameter pendukung. Hasil penelitian menujukkan bahwa perendaman abate tidak efektif untuk menurunkan derajat infestasi menginfestasi ikan mas (C. carpio), akan tetapi dapat menimbulkan kerusakan organ Argulus pada perlakuan 100 ppm. Kerusakan organ Argulus yang ditimbulkan yaitu rontoknya kaki ke-3 dan 4, abdomen yang menyatu serta produksi telur prematur. Perlu dilakukan penelitian lanjutan dengan meningkatkan dosis abate (lebih dari 100 ppm) serta waktu inkubasi yang lebih lama (lebih dari 30 menit). Selain itu perlu diamati perubahan fisiologis ikan selama dilakukan perendaman dalam abate.