The proximate composition, amino acid profile, fatty acid content, and mineral content of scale flour from three fish species as potential feeds for fish fry.

Background: Fish scale waste is highly valued both as a functional food ingredient and a potential feed source for farmed fish. This study aimed to analyse the chemical composition, fatty acid profile, and mineral content in fish scale flour of Osphronemus (O) goramy, Cyprinus (C) carpio, and Oreochromis (O) niloticus as potential feed for fish fry. Methods: Fish scales were cleaned with 10% w/v NaCl solution at a ratio of 1:10 (w/w) for 24 hours at 4 °C. Agitation was used every eight hours to remove excess protein. Fish scales were evenly arranged in a cooker and cooked at 121 °C for 10 minutes with 15 psi pressure. After cooking, 100 grams of wet fish scales was dried at 50 °C for four hours. Dried fish scales were transformed into flour for proximate composition analysed via standard AOAC method, amino acid and fatty acid assessment employing HPLC and GC-MS, while mineral content was determined using AAS. Results: The examined fish scale flour from three species displayed significant variations in chemical components, amino acids, and minerals (p<0.01). Crude protein content spanned 49.52% to 72.94%, and fat content ranged from 0.11% to 0.23%. Magnesium levels varied between 767.82 mg/kg and 816.50 mg/kg, calcium content ranged from 3.54 mg/kg to 12.16 mg/kg, iron content was within 40.46 mg/kg to 44.10 mg/kg, and zinc content ranged from 45.80 mg/kg to 139.19 mg/kg. Predominantly, glycine emerged as the main free amino acid (FAA), varying from 13.70% to 16.08%, while histidine had the lowest content, at 0.39% to 0.71%. Conversely, fatty acid content was low in all species examined ranging from 6.73% to 9.48%. Conclusions: Flour from three farmed fish types has potential for fish fry feed due to its chemical composition, amino acid, and mineral content. Further validation is needed for amino acid comparison to fish meal.

Effect of feed enriched by products formulated from coconut water, palm sap sugar, and mushroom on the chemical composition of feed and carcass, growth performance, body indices, and gut micromorphology of giant gourami, Osphronemus goramy (Lacepède, 1801), juveniles.

Background: Giant gourami, Osphronemus goramy is the most important freshwater fish species produced by aquaculture in Indonesia. This study aimed to 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: One hundred gram 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). Two litres of coconut water were then mixed with the litre of palm sugar solution. One 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 m 3) 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 (r 2 = 92%), condition factor (r 2 = 77%), protein efficiency ratio (r 2 = 75%), while a moderate relationship with the feed intake ( r 2 = 69%). Conclusions: Diet KP3 contains higher total amino acids in diets and carcasses and leads to feed efficiency and better growth for giant gourami.

Growth, production and feed conversion performance of the gurami sago (Osphronemus goramy Lacepède, 1801) strain in different aquaculture systems.

Background: Giant gourami ( Osphronemus goramy, Osphronemidae), belonging to gurami sago strain, is an important economic fish species that was newly released for domestication in 2018 in Indonesia. The present study aimed to determine the growth, production and feed conversion efficiency of gurami sago strain in different aquaculture systems. Methods: A mean of 240 juveniles were stocked (initial weight mean, 54.53 g and length 13.88 cm) into concrete ponds, floating net cages and earthen freshwater ponds (12 m 3) with three replicates of each. The juveniles were fed a floating commercial pellet diet containing 30% crude protein and 5% crude lipids. Feed was supplied at 3% of fish biomass per day throughout the 90 days of the experiment. The research was conducted in the area surrounding Lake Maninjau of Indonesia. Results: After 90 days, the mean weight of fish reared in concrete ponds was 166.86 g, floating net cages was 179.51 g and earthen freshwater ponds was 149.89 g. The mean final biomass was 37.64 kg for concrete ponds, 41.27 kg for floating net cages, and 33.72 kg for earthen freshwater ponds. The specific growth rates (%/day) for concrete ponds, floating net cages and earthen freshwater ponds were 0.67, 0.75 and 0.62, respectively. The feed conversion rates were 1.45 for concrete ponds, 1.30 for floating net cages and 1.87 for earthen freshwater ponds. The net yields (kg m -3) were 2.05 for concrete ponds, 2.27 for floating net cages, and 1.73 for earthen freshwater ponds. The exponents (b) of the length-weight relationship were calculated for concrete ponds (1.0146), floating net cages (1.2641), and earthen freshwater ponds (1.0056). Conclusion: The study showed that the growth performance, production and feed conversion efficiency of the gurami sago strain were the best found in floating net cages and considered a new aquaculture system in the future.

Evaluation of Formulated Diets Enriched by Spinach Extracts for the Broodstock Females, Portunus pelagicus (Linnaeus, 1758).

BACKGROUND AND OBJECTIVE: Spinach extract (Amaranthacea tricolor) is a very prospective feed raw materials to stimulate the molting and growth of crab female broodstock. The purpose of this study was to evaluate the quality of broodstock females, Portunus pelagicus (Linnaeus, 1758) at different levels of spinach extract based on physical, organoleptic and chemical tests. MATERIALS AND METHODS: Four different treatments of spinach extract (0, 250, 500 and 750 ng g-1 crab, respectively) were used in this study. The female crab samples were collected from coastal region of Padang, West Sumatera and placed randomly in four concrete tanks (200×100×100 cm). Each concrete tank consist of five units of plastic box (45.5×32.5×16.5 cm) with the maximum density was one crab per box. RESULTS: The organoleptic test showed that formulated diets enriched with spinach extract (0, 250 and 500 ng g-1 crab) had a smooth texture, pungent aroma and brown. Whereas from the physics test results obtained good water stability (rupture velocity ranged from 89.20-105.40 min and solids dispersion ranged from 4.97-7.17%), hardness (92.66-98.07%) and sinking velocity (3.88-5.88 cm sec-1) (p<0.05). The results also showed that formulated diet enriched with spinach extract doses of 250-750 ng g-1 crab gave a value of delicacy of feed (0.195-0.386 g crab-1 weight/day) which was significantly different (p<0.05) with 0 ng g-1 crab (0.445 g crab-1 weight/day). The chemical test shows the moisture content were 11.60%, ash 9.31%, protein 44.38%, fat 7.64% and carbohydrate 14.46%. CONCLUSION: It was concluded that there was a linear relationship between dose of spinach extracts in formulated diet and rupture velocity and a quadratic relationship between dose of spinach extracts in formulated diet and solid disperse, hardness and sinking velocity and delicacy of feed.

Diversity and distribution of fish fauna of upstream and downstream areas at Koto Panjang Reservoir, Riau Province, Indonesia.

Background: The capture fishery sectors in the river and reservoir play an important role in the Indonesian economy through increased income and diversification of livelihoods. The present study was conducted to ascertain fish diversity and their distribution pattern in the upstream and downstream areas of Koto Panjang Reservoir, Riau Province-Indonesia. Methods: Fish samples were collected for a period of 12 months using a variety of fish nets at four sites; Koto Mesjid (KM) and Batu Bersurat (BB), located in the upstream area of Koto Panjang Reservoir and Rantau Berangin (RB) and Kuok (KK), located in the downstream area of Koto Panjang Reservoir. Data obtained were analyzed using standard taxonomic keys based on morphometric characters. Results: A total of 44 species belonging 19 families and 33 genera were recorded in the study area. Alpha diversity indices showed that fish diversity in this area was quite high (Shannon's index = 2.10 and Simpson-D = 0.21) and evenness was low (evenness H/S =0.19). The fish in KM and BB sites (upstream) were from eight and 11 families, respectively. In RB and KK sites (downstream), fish were from 16 and 15 families, respectively. In KM, BB, RB and KK sites, the dominant family was Cyprinidae, comprising 33.45%, 50.95%, 43.04% and 39.35% of all fish caught at each site, respectively. Exotic species, especially Nile tilapia, were 20.15%, 14.11%, 5.62%, and 5.34%, respectively. Some differences were also noted between the upstream and downstream reservoirs, with a slight increase in exotic species in the upstream reservoir over the study period (from 11.39% vs. 34.66%), corresponding to decrease of native species (from 88.61% vs. 65.34%). Conclusions: The diversity and distribution of fish fauna were varied in upstream and downstream areas of Koto Panjang Reservoir. The exotic species were found to be dominant in the upstream reservoir areas.

Morphometric Characteristics of Asian Catfish, Hemibagrus wyckii (Bleeker, 1858) (Bagridae), from the Riau Province of Indonesia.

BACKGROUND AND OBJECTIVE: Asian Catfish (Hemibagrus wyckii) is an important fish having both food and a high price in the market. These species are categorized as a carnivorous freshwater finfish native in Indonesia and is vulnerable to endangered status. This study was carried out to identify the morphometric characteristics of Hemibagrus wyckii (H. wyckii) from the Koto Panjang Reservoir, Kampar Kanan and Kampar Kiri rivers. MATERIALS AND METHODS: Twenty-five fish were collected from each sampling site. The morphometric characteristics were analyzed using the truss morphometric method. Twenty-nine characteristics were measured to obtain the morphometric characteristics of this species. Morphometric data of H. wyckii were analyzed using one-way ANOVA (SPSS version 17.0). Principal component analysis (PCA) was used to evaluate the relationship between different factors and morphometric characteristics. The distribution across different habitats was measured by component canonical analysis (CCA) and genetic distance was analyzed by hierarchical cluster. RESULTS: The average standard lengths of H. wyckii from the Koto Panjang Reservoir, Kampar Kanan and Kampar Kiri rivers (Mean±SD) were 428±15.78, 432.52±66.11 and 425.86±50.41 mm, respectively. Twenty-nine morphometric characteristics were measured. There was a 68.96% difference obtained in samples collected at the Koto Panjang Reservoir and Kampar Kanan river. There was a 95.55% difference obtained in the Koto Panjang Reservoir, Kampar Kiri river and a 100% difference obtained in the Kampar Kanan and Kampar Kiri rivers. The main differences in morphometric characteristics included inter orbital distance, length of adipose-fin base, predorsal length, length of front dorsal fin-front pelvic and depth of caudal peduncle. The Mahalanobis distance between fish from the Koto Panjang Reservoir and Kampar Kanan river demonstrated that both types originated from a single population. CONCLUSION: It was concluded that more favorable morphometric characteristics of H. wyckii were found in the Kampar Kanan river compared to those from the Koto Panjang Reservoir and Kampar Kiri river.

Influence of Different Stocking Densities on Growth, Feed Efficiency and Carcass Composition of Bonylip Barb (Osteochilus vittatus Cyprinidae) Fingerlings.

BACKGROUND AND OBJECTIVE: Bonylip barb (Osteochilus vittatus) is an herbivorous freshwater fin-fish species native in Indonesia. These species has high demand and price in the market. A 90 days study was conducted to evaluate the effects of different stocking densities on growth, carcass composition, survival and water quality of Osteochilus vittatus (O. vittatus) in a synthetic sheet pond. MATERIALS AND METHODS: Fingerlings with an average weight of 2.45±0.071 g (Mean±SD) were randomly stocked in 12 synthetic sheet ponds (2×1 m) at densities of 50 fish m-3 (T50), 75 fish m-3 (T75), 100 fish m-3 (T100) and 125 fish m-3 (T125) in triplicate groups. One-way ANOVA followed by Duncan's new multiple range test was used to analyze obtained data a significance level of p<0.05. RESULTS: After 90 days of the trial, the growth in terms of weight gain (WG) and specific growth rate (SGR) of fish from T50 were significantly higher than those from T75, T100 and T125. The feed conversion ratio (FCR) was significantly lower in T50 followed by T75, T100 and T125 consecutively. Protein efficiency ratio (PER) was higher in T50 followed by T75, T100 and T125 consecutively. The survival rate (SR) of the fish from T50 was significantly higher than that of the fish from T75, T100 and T125. Significantly lower amounts of carcass lipid and carbohydrate contents were found in T125 compared to the contents of the T50, T75 and T100 fish. CONCLUSIONS: Based on the growth performance and feed efficiency, the T50 fish m-3 of O. vittatus in a synthetic sheet pond may be technically feasible.