The Effectiveness of Turmeric and Maggot Enriched Pellets to Improve Growth and Survival of Osphronemus goramy

Fishball tofu (FBT) is a diversification product of meatball tofu which was specially produced in Semarang Central Java Indonesia. Meatball tofu is usually made from beef. FBT is produced from fish flesh. Caharacteristics of FBT from different species with different concentration of flesh was investigated. The experimental design in this study was a factorial completely randomized design with different species (giant gourami and catfish) at varying flesh concentrations (30%, 40% and 50%). Fish species and flesh concentration had significant effect on protein and fat content of FBT (P<0.05). No difference of gel strength was observed for FBT from giant gourami and catfish at flesh concentration of 50% and 30%, respectively (P>0.05). The highest protein content (11.42%) was achieved for FBT from catfish at 50% flesh concentration and the lowest protein content (8.08%) was observed for FBT from giant gourami at 30%. FBT from giant gourami at 50% flesh concentration had the highest fat content, meanwhile FBT from catfish at 30 and 40% showed the lowest fat content. Fish species and flesh concentrations did not have significant impact on moisture and ash contents of all FBT samples (P>0.05). The moisture and ash contents of all FBT were of 69.25-71.15% and 0.59-0.86%, respectively. Different species and flesh concentration had a significant effect on the hardness, deformation and gel strength (P<0.05). The highest hardness was achieved for FBT from giant gourami at 50% flesh concentration (P<0.05). The highest deformation was attained for FBT from catfish at 30% flesh concentration and the lowest deformation was found in FBT from giant gourami with 50% flesh concentration (P<0.05). The deformation values of FBT from catfish were greater (11.4-23.73 mm) than those from giant gourami (10.33-13.9 mm). Overall, FBT from catfish are preferred than those from giant gourami.

Abstract. Sari DN, Nasrullah H, Ekasari J, Suprayudi MA, Alimuddin A. 2021. Sequence and expression analysis of glucokinase mRNA from herbivorous Giant gourami (Osphronemus goramy). Biodiversitas 22: 741-750. Glucokinase (GCK) is one of the enzymes that play important roles in carbohydrate metabolism and high glucose homeostatic in fish. The information about the GCK mRNA sequence and its expression is limited in Giant gourami, one of the most important herbivorous aquaculture species in Indonesia. The present study aimed to characterize the GCK mRNA and analyze its mRNA expression and plasma glucose levels after high glucose injection in Giant gourami. We also compared its sequence variability among carnivorous and herbivorous fish. The GCK mRNA was identified using polymerase chain reaction (PCR) method from the fish liver. Its mRNA level was analyzed by real-time PCR (qPCR). Giant gourami GCK mRNA sequence was 2104 nucleotide long, encoding 478 amino acids, and shared high similarity with other fish. GCK was mainly expressed in the liver. The mRNA level of GCK was highly up-regulated after 6 hours of high glucose injection, in-line with the plasma glucose in the blood. There are no major differences observed in the GCK amino acid sequences among Giant gourami and other fish. The knowledge gained from this study could be used as a reference for further exploration of metabolic regulation in Giant gourami.

The outbreak of bacterial disease often occurs in giant gourami (Osphronemus goramy) fish cultures. Banjarnegara Regency is the center of production of giant gourami (O. goramy) in Central Java, Indonesia. Thus, this research aimed to address the causative bacterial agent in giant gourami, based on 16S rRNA gene sequences. Twelve moribund fishes were collected from traditional fishponds of Banjarnegara Regency for bacterial isolation, and 440 juveniles were used to conduct Postulat Koch. Results showed that 21 bacterial isolates (SJB 01 – SJB 21) were isolated from kidney and external wounds of fishes from both GSP and TSA media. Postulate Koch assay indicated that four isolates (SJB 02, SJB 03, SJB 12, and SJB 14) led to fish mortality up to 60%, whereas illness was about 20% – 80%. Therefore, these isolates were potentially the causative agent of bacterial diseases in giant gourami. Based on the analysis of the 16S rRNA gene, the isolate SJB 02, SJB 03, SJB 12, and SJB 14 were closely related to Aeromonas hydrophilla (97.55%), Aeromonas veronii (98.92%), Pseudomonas otitidis (98.45%), and Aeromonas jandaei (97.74%), respectively.

The severe mortality of fish due to the infection of megalocytivirus caused significant economic losses. Since 2011, megalocytivirus (giant gourami iridovirus (GGIV)) has become the main pathogen in giant gourami (Osphronemus goramy), particularly in West Java, Central Java and Bali. This study aimed to develop primary cell culture from spleen as the target organ for propagating megalocytivirus in vitro, which was developed by explant method with enzymatic dissociation. Optimization was carried out at incubation temperature, medium and serum concentrations. The origin of the primary cell, cell susceptibility and GGIV pathogenicity were observed. The results showed that the primary cell (GP cells) can grow well in 10% foetal bovine serum L-15 medium at 27°C, which was sufficient for cell growth. PCR and BLAST analyses showed the primary cell was originated from giant gourami. In infected GP cells, cell enlargement and cell rounding were observed. Virus propagated in GP cells was highly virulent when injecting giant gourami in an artificial infection experiment. Intraperitoneal injection of diluted virus supernatant showed 100% mortality in 7-11 days post-injection and 97% mortality in 21days post-cohabitation, with abnormalities observed in spleen and kidney. In conclusion, GP cell was successfully subcultured for more than 30 passages and susceptible to GGIV.

Disease outbreaks and mortality in giant gourami and Asian catfish (pangasius) culture have been frequently reported during the last decade. Etiological agents of the disease have remained unknown, so it is needed to explore epidemiological studies to know the main causative agents. The study aimed to know the main pathogenic agents who were identified during disease outbreaks on giant gourami and pangasius. Data and information were collected through active and passive surveillance at the production centers of each species. Analysis was carried out according to standard fish disease diagnosis and eventually was focused on two suspected new emerging diseases (NED), namely Infectious Spleen and Kidney Necrosis Virus (ISKNV) belonging to Megalocytivirus on giant gourami and Enteric Septicemia of Catfish (ESC) caused by Edwardsiella ictaluri on pangasius. The results showed that ISKNV was detected on most of the diseased giant gourami samples and that E. ictaluri was identified on most diseased pangasius samples. This study concluded that both pathogenic agents, Megalocytivirus and E. ictaluri were suspected to be potentially NED on freshwater aquaculture, especially infecting giant gourami and pangasius respectively.

Tilapia Lake Virus (TiLV) is a New Emerging Disease that has been defined and included in the WOAH disease list (WOAH, 2022). This virus can infect both freshwater and marine fish, causing high mortality in Ttilapia up to 90%. Reverse transcyptase method - Semi Nested Polymerase Chain Reaction (RT-snPCR) for detection of TiLV in Osphronemus goramy. TiLV was discovered for the first time in Thailand and was also found in Jogjakarta in 2021. Further research is needed to see the damage and genetic variation caused by TiLV in Osphronemus goramy. This study aims to study the genetic variability and homology of TiLV isolates in Osphronemus goramy as definitive hosts in East Java. The results showed clinical symptoms of lethargic fish, decreased appetite, abnormal behavior, reduced reflexes, sluggish movements, darker body color, congestion, thinning fins and exopthalmia. The PCR results showed that the Osphronemus goramy showing clinical symptoms of TiLV infection were all positive. The sequencing results were further identified using the BLAST program, showing the highest similarity of the genetic identity of the sample at 96.8% with TiLV from Israel (Genebank Accession Number NC 029927.1).

Megalocytivirus of family Iridoviridae has been identified as a pathogen that caused the fatal systemic infection to lead to massive death of numerous fish species in both ornamental and food fish industries. It caused significant economic losses due to severe mortality of infected fish. Since 2011 in Indonesia, megalocytivirus in giant gourami (Osphronemus goramy) had been found as the main pathogen in some cases of giant gourami outbreak, especially in West Java, Central Java, and Bali. The aim of this study is to identify and characterize the pathogen known as a megalocytivirus infection in freshwater-cultured giant gourami. We identified the virus using universal and specific primers for megalocytivirus and infectious spleen and kidney necrosis virus (ISKNV). Sequencing and BLAST analysis were used to develop a phylogenetic tree. The result showed that phylogenetic analysis of major capsid protein (MCP) gene unveiled a new member of megalocytivirus, designated as giant gourami iridovirus (GGIV). GGIV-formed cluster belonged to ISKNV and has 100% homology to ISKNV complete genome. Artificial infection by intraperitoneal injection with supernatant homogenate from spleen and kidney of naturally infected fish showed 93% cumulative mortality in 12 days. Fish showed a clinical sign of infection as lethargic, loss of appetite, pale or darken body color, and hemorrhages. Internal organ on dead fish showed swollen spleen and kidney and also a pale liver. Quantitative PCR analysis on internal organs showed spleen had the highest viral DNA copy number followed by kidney, gill, and liver. Histopathological analysis showed many abnormally hypertrophied cells in spleen which is typical histopathological characteristic of megalocytivirus infection. In conclusion, GGIV belonged to ISKNV from genus megalocytivirus.

Background: Giant gourami, Osphronemus goramy (Lacepède, 1801) is the most important freshwater fish species produced by aquaculture in Indonesia. This study seeks to determine the effects of various newly formulated products on the amino acid composition of the diet and whole-body carcass, and to analyse the growth coefficient, body indices, and gut micromorphology. Methods: 100 g of palm sap sugar was cooked in 1.1 litre of fresh water for fifteen minutes, to create 1 litre of 11% palm sap sugar solution (after some of it had been boiled off). 2 litres of coconut water were then mixed with the litre of palm sugar solution. 1 litre of this product was added in turn to 2 g of Aspergillus niger (CP2), 2 g of Rhizopus oligosporus (CP3), and 2 g of Saccharomyces cerevisiae (CP4), while freshwater was used as a control (labeled CP1). Aquafeed was added to CP1, CP2, CP3, and CP4, to make diets labeled KP1, KP2, KP3, and KP4. The dosage was 150 ml/kg of feed. Juvenile giant gourami (initial weight 50±0.25 g and length 13.2±0.07 cm) were reared in triplicate net frames (2×1×1 m; water volume 1.5 m3) in a freshwater concrete pond with a stocking density of 30 juveniles/net. Results: The results supported our hypothesis that different product formulations have a significant effect (P < 0.05) on aquafeed nutrition and the whole-body carcass, growth coefficient, feed utilization, body indices, and gut micromorphology of giant gourami juveniles. The thermal growth coefficient strongly correlated with the daily growth coefficient (r2 = 91%). The KP3 diet contains a higher concentration of amino acids, which increased the growth coefficient, feed utilization, and carcass quality more than the other diets we tested. Conclusions: Diet KP3 contains higher total amino acids in diets and carcasses and leads to better growth for giant gourami.

Giant gourami (Osphronemus goramy) is one of the main aquaculture commodities in Indonesia, originally distributed across the waters of Java, Sumatra and Borneo. This study aims to determine the genetic variation of giant gourami in Indonesia through morphometric and molecular analyses using mitochondrial DNA marker Cytochrome Oxidase Subunit I (COI). Morphometric assessment revealed a low average coefficient of variance, ranging from 2% to 20%. Correlation analysis indicated that the forehead and caudal peduncle were key distinguishing characteristics of giant gourami. Discriminant and cluster analyses classified giant gourami into three geographical populations: Java, Sumatra, and Borneo. A similar clustering pattern was observed in the molecular analysis results. Our study concluded that the giant gourami populations in Indonesia exhibit distinct haplotypes and cluster according to their island of origin. The Sumatra and Java populations showed a closer genetic relationship compared to the Borneo samples, as reflected in both genetic distance and morphometric assessment.

Giant gourami (Osphronemus goramy) has been known to have a high ability to utilize high dietary carbohydrates. However, its molecular information related to carbohydrate metabolism is still limited. The present study elucidated Giant gourami's liver transcriptome and molecular responses to high dietary carbohydrates. Two semi-purified diets with different levels of dietary carbohydrate, normal carbohydrate (34%, N34) and high carbohydrate (53%, H53), were offered to the fish for 60 days. A total of 87,430,553 clean reads were collected and assembled into 49,034 cDNA contigs. Annotation was performed, and a total of 33,104 unigenes were obtained. High dietary carbohydrates generally down-regulated the differentially expressed genes (DEGs). The genes expression related to glycolysis and the antioxidant system were significantly upregulated (P<0.05). Meanwhile, the genes expression related to insulin signaling and gluconeogenesis were significantly downregulated (P>0.05). The results showed that Giant gourami has several adaptabilities for high carbohydrates. The upregulation of the glycolytic, gpx, and noa1 genes, downregulation of insulin signaling, and gluconeogenic genes indicated a good glucose homeostasis maintenance in Giant gourami.

Seasonal variation of giant gourami (Osphronemus goramy) spawning activity and egg production in aquaculture ponds

New insights into giant gourami (Osphronemus goramy) reproductive biology and egg production control

Fate of commercial pellets and role of natural productivity in giant gourami ponds using stable isotope analyses

The commercial complex enzymes containing protease, lipase, and amylase are potentially used for exogenous dietary enzymes on giant gourami (Osphronemus goramy) as growth booster indirectly. The aims of this study are to know the effect of the exogenous dietary enzymes on giant gourami growth and to obtain the optimal dose of this enzyme. The research was conducted on January-April 2019 in the aquaculture facility and laboratory of Universitas Airlangga, Banyuwangi Campus. A total of 200 giant gourami juveniles (5.5 ± 0.5 cm in total length) were obtained from the fish hatchery centre of Kabat, Banyuwangi, Indonesia. All fish was divided into 20 glass aquaria (40 x 30 x 30 cm3) and reared for 40 days with exogenous dietary enzyme treatments in the diets following: control (no enzyme), 2.5 ml/100 g feed, 5.0 ml/100 g feed, 7.5 ml/100 g feed, 10.0 ml/100 g feed (4 replication in each treatment). The parameters were observed in this study are daily growth rate (DGR), specific growth rate (SGR), and feed conversion ratio (FCR). The exogenous dietary enzyme significantly (P < 0.05) effect to all parameters, the best result was showed in 10.0 ml/100 g feed treatment as optimum applicate dose.

Highlight Research 1. Lymphocystis disease is reported to infect seawater and freshwater fishes 2. The four important freshwater fish species in Indonesia are evaluated on their susceptibility to Lymphocystis Disease Virus 3. Lymphocystis infection causes behavioural changes and mortality with different onset times after infection on the four fish species 4. LCDV load is varied in quantity among different organs. Abstract Lymphocystis disease has a broad host range and has been reported to enter Indonesia. However, information regarding its susceptibility and predilection organs in fish is lacking. This study examined the susceptibility of four important fish species in Indonesia, namely, giant gourami (Osphronemus goramy), hybrid tilapia (Oreochromis sp.), Siamese fighting fish (Betta splendens), and hybrid catfish (Clarias sp.). The fish were infected with virus filtrate by intraperitoneal injection and immersion. The postinfection observation period was 60 days. Viral load was quantified by qPCR and expressed as major capsid protein (MCP) copy number/mg tissue. Mortality was observed in all fish species, with the highest recorded in hybrid catfish and the lowest in Siamese fighting fish. All the fish species showed changes in their clinical symptoms, such as anorexia and separation from schools. However, only giant gourami showed internal change seven days after injection (dpi), with white lesion detected in the liver. Viral load quantification showed that LCDV had different predilection organs in the four fish species. The highest viral load of giant gourami (1.7 x 104) was observed in the liver at 7 dpi, hybrid tilapia (7.5 x 103) was observed in the fins at 21 dpi, Siamese fighting fish (8.4 x 103) was observed in the fins at 14 dpi, and hybrid catfish (1.2 x 103) were observed in the fins and gills at 7 and 14 dpi. The findings indicated that giant gourami, hybrid tilapia, Siamese fighting fish, and hybrid catfish were susceptible to LCDV infection with different predilection organs.