Fish Body Weight Research Articles

The Effect of Short-Term Artificial Feed Domestication on the Expression of Oxidative-Stress-Related Genes and Antioxidant Capacity in the Liver and Gill Tissues of Mandarin Fish (Siniperca chuatsi).

To investigate whether Mandarin fish developed oxidative stress after being domesticated with artificial feed, we conducted a series of experiments. Oxidative stress is an important factor leading to diseases and aging in the body. The liver integrates functions such as digestion, metabolism, detoxification, coagulation, and immune regulation, while the gills are important respiratory organs that are sensitive to changes in the water environment. Therefore, we used the liver and gills of Mandarin fish as research materials. The aim of this study was to investigate the effects of short-term artificial feed domestication on the expression of oxidative stress genes and the changes in oxidative-stress-related enzyme activity in the liver and gills of Mandarin fish. We divided the Mandarin fish into two groups for treatment. The control group was fed with live bait continuously for 14 days, while the experimental group was fed with half artificial feed and half live bait from 0 to 7 days (T-7 d), followed by solely artificial feed from 7 to 14 days (T-14 d). The experimental results showed that there was no difference in the body weight, length, and standard growth rate of the Mandarin fish between the two groups of treatments; after two treatments, there were differences in the expression of genes related to oxidative stress in the gills (keap1, kappa, gsta, gstt1, gstk1, SOD, and CAT) and in the liver (GPx, keap1, kappa, gsta, gstt1, gr, and SOD). In the liver, GPx activity and the content of MDA were significantly upregulated after 7 days of domestication, while in the gills, SOD activity was significantly upregulated after 7 days of domestication and GPx activity was significantly downregulated after 14 days of domestication. These results suggest that artificial feed domestication is associated with oxidative stress. Moreover, these results provide experimental basic data for increasing the production of aquaculture feed for Mandarin fish.

Experimental analysis of the effect of low water temperature on oogenesis of juvenile chum salmon

The state of gonads is examined for juvenile chum salmon exposed for two weeks at low water temperature, for different stages of their embryonic-larval development. The transfer of the embryos and larvae from the water with temperature of 10.0–12.0 о C to the water with temperature of 1.3–1.8 о C slowed both somatic growth of the fish and development of their germ cells in all cases. The deficit in body weight and ovarian weight of experimental fish was not compensated later. However, the gonad weight was decreased in the somatic component and did not affect the fund of germ cells, in the medium term. The state of ovaries did not differ between the control and experimental groups of fish 50 days after the end of exposure, regardless of the initial condition of gonads in the experiment.

Investigation of Anisakis infections in coastal marine fishes and awareness of anisakiasis control knowledge among residents in Yantai City in 2021

To investigate the prevalence of Anisakis infections in coastal marine fishes and awareness of anisakiasis control knowledge among local residents in Yantai City, Shandong Province in 2021, so as to provide insights into formulation of anisakiasis control interventions. Marine fishes were purchased from Shunxin Port, Yantai City, Shandong Province in November 2021, and the presence of Anisakis was detected in different species of fishes and different fish sites. The correlations between body length and weight of marine fish and intensity of Anisakis infections were examined using Spearman's rank correlation analysis, and the dietary habits and anisakiasis control knowledge were investigated using questionnaire surveys among local residents. A total of 201 marine fishes belonging to 20 species were dissected, and Anisakis was detected in 77 marine fishes (38.31%) belonging to 11 species (55.00%), with a mean infection intensity of 45.04 parasites per fish (3 468/77). Spearman's rank correlation analysis revealed that the body length (rs = 0.74, P < 0.05) and weight (rs = 0.79, P < 0.01) of the monkfish correlated positively with the intensity of Anisakis infections, and the body length (rs = 0.68, P < 0.05) of the flatfish correlated positively with the intensity of Anisakis infections, while no correlations were examined between the body length or weight of other marine fishes and the intensity of Anisakis infections. Of all respondents, 53.38% men and 56.67% women did not know anisakiasis control knowledge at all, and there was a significant difference in the proportion of respondents using separate chopping boards for raw and cooked food from different villages (χ2 = 17.89, P < 0.01), while there was an age-specific proportion of respondents with habitats of eating raw or semi-raw seafood (χ2 = 28.27, P < 0.01). The prevalence and intensity of Anisakis infections were high in coastal marine fishes in Yantai City in 2021, and the awareness of anisakiasis control knowledge was low among local residents. Intensified health education pertaining to anisakiasis control knowledge is recommended to reduce the risk of Anisakis infections.

Black Soldier Fly Larvae Meal vs. Soy Protein Concentrate Meal: A Comparative Digestibility Study in Barramundi (Lates calcarifer)

Black soldier fly larvae meal (BSFM) from Hermetia illucens has emerged as a dependable protein source in aquaculture. This study aimed to assess BSFM’s digestibility in barramundi juveniles and compare it to soy protein concentrate meal (SPCM). Four diets (control, 30% BSFM; 30% SPCM; and commercial feed control) were tested on 1,800 barramundi juveniles (weight: 71.1 g) over 51 days in a recirculating aquaculture system (RAS). The final body weight (FBW) of fish fed with BSFM reached 222.2 (± 8.7), with a thermal-unit growth coefficient (TGC) of 4.33 (± 0.15) and a feed conversion ratio (FCR) of 1.04 (± 0.01). While BSFM and SPCM inclusion did not significantly impact FBW, body weight gain (BWG), TGC, or survival rates (P &gt;0.05), FCR increased. BSFM significantly raised total feed intake (P&lt;0.05) but did not affect daily feed intake (P &gt;0.05). Importantly, BSFM and SPCM inclusion did not alter diet apparent digestibility coefficient (ADC) for any nutrient groups (P &gt;0.05), with BSFM showing high ADC for dry matter (76.8%), crude protein (93.2%), and gross energy (83.9%). No significant difference (P &gt;0.05) was observed in these ADCs between BSFM and SPCM. The high digestibility of BSFM in warm seawater RAS (29.4°C) under high stocking density (33.7 kg m−3) supports its efficacy in contemporary barramundi farming.

Effect of Different Ages of African catfish (Clarias gariepinus) Broodstock on Reproductive Performance and Fries Production

This study was conducted at the hatchery complex of Akwa Ibom State University to investigate the effect of different ages of African catfish (Clarias gariepinus) on their reproductive performances. Eighteen (18) broodstock of Clarias gariepinus (3 males and 3 females) from each age group, six months, twelve months and eighteen months old with average body measurement of 1.1kg and 32cm for six month, 1.8kg and 43cm for 12 months and 2.5 kg and 65.7cm for 18 months were selected from AKSU fish farm labeled treatment A, B and C for the study. 3 male broodstock from each treatment were sacrificed for milt extraction without hormonal inducement. The milt from each treatment were separately pooled into one volume and divided into three portions each diluted with 2ml of normal saline solution. Three female broodstock from each treatment were separately induced with ovaprim at a single dosage of 0.5ml/kg body weight of fish and allowed for a latency period of ten hours at water temperature of 26oC before stripping manually. 3g of egg from each broodstock was mixed with the diluted milt and activated with 100 mls of normal saline. The fertilized eggs were incubated in aerated indoor concrete tanks in 3 replicates. % fertilization were accessed six (6) hours after incubation, % hatchability was accessed twenty-six hours (26) after incubation, while the percentage survival and fry production success in each treatment was accessed after ten (10) days post hatching. The results reveal that the reproductive parameters considered in this study significantly (p&lt;0.05) increased with age of broodstocks. The percentage fertilization of egg from the least to the oldest broodstock were 63.67± 0.88, 69.50 ± 0.87 and 81.83 ± 5.05 respectively. The percentage hatchability of the oldest broodstock was 82.62 ± 1.6 significantly (P&lt; 0.05) higher than 64.79 ± 2.74 (12 months) with the least value of 49.04 ± 5.76 recorded for six-month-old broodstock. The oldest broodstock had the highest percentage survival 83.14 ± 3.16 and fry production success of 56.05± 0.06 while the least broodstock (6-month-old) had the least value of survival 54.59 ± 2.42 and fry production success of 17.17 ± 2.59%.

Comparative evaluation of raw and fermented Eichhornia crassipes leaf meal in the diet of Cyprinus carpio fingerlings: Effects on growth performance, body composition and haemato-biochemical responses

Eichhornia crassipes leaf meal (ELM) was fermented by solid-state fermentation using Chaetomium globosum MTCC 4179 that resulted in considerable changes in its nutrients and anti-nutrient profile. Both fermented ELM (FELM) and raw ELM were evaluated in the feed of Cyprinus carpio fingerlings through a feeding trial of 56 days. Five iso-nitrogenous and iso-caloric diets viz. C, Control (30% DORB and 0% ELM or FELM), ELM15 (15% ELM with replacement of 50% DORB), ELM30 (30% ELM with replacement of 100% DORB), FELM15 (15% FELM with replacement of 50% DORB), and FELM30 (30% FELM with replacement of 100% DORB) were prepared and fed on satiation basis to 180 acclimated fish (body weight 8.38–8.48 g) of five respective groups in triplicate with the stocking density of 12 fish /tank. Significantly (P<0.05) higher weight gain (%), specific growth rate, and protein efficiency ratio and lower feed conversion ratio (FCR) were observed in ELM15 and FELM15 groups compared to the control. However, the growth performance of ELM30 and FELM30 groups showed no significant (P>0.05) difference with control group. Furthermore, fermented diets (FELM15 and FELM30) could not improve the growth performance of fish as compared to their non-fermented counterparts (ELM15 and ELM30). Total red blood cell count, packed cell volume (%), and total serum protein (g/dl) were significantly (P<0.05) higher in ELM15 compared to other ELM and FELM-based groups. Better body composition was observed in fish of ELM15 group, however, fish of control, and ELM30 showed similar body protein, lipid, ash and total carbohydrate. Thus, it is concluded that raw ELM can be incorporated in the diet of common carp up to the level of 30% with complete replacement of DORB without compromising the growth performance of fish. However, the fermentation of ELM with Chaetomium could not impart any additional benefits in terms of growth performance of fish. In addition, dietary inclusion of 15% raw or fermented ELM, in replacement of 50% DORB, can result in higher growth performance with better health condition of common carp fingerlings.

Adaptive responses of feeding and swimming behaviors in black rockfish, Sebastes schlegelii, under starvation at juvenile and young stages

Starvation is a ubiquitous stress that many fish species have to cope with. To investigate the behavioral responses under this pressure in the fry stage, black rockfish (Sebastes schlegelii) at juvenile (29 days of age, 15.2 ± 1.0 mm in total length) and young (51 days of age, 40.3 ± 1.2 mm in total length) stages were starved for 12 and 21 days, respectively. During these two periods of starvation, the starved and routinely fed individuals (serving as the control group) were sampled to be analyzed the variations in growth, survival, feeding activity, swimming ability (cruise and burst), and diet transition process. The results indicated that juveniles were more sensitive to hunger, and the point of no return (PNR) was approximately 5.5 days (19 ℃ in water temperature). In contrast, the young fish had a significantly higher tolerance to starvation because the survival rate after 21 days of starvation was still higher than 99% (20 ℃). The total length and body weight of juveniles and young fish showed different degrees of negative growth. After the starvation for 1 day, the juveniles’ feeding activity on shrimps increased significantly (p < 0.05), while their cruising speed and time changed insignificantly. Similar results were observed in young fish been starved for 1–3 days. With the prolongation of starvation, however, both the feeding and cruising activities of black rockfish became significantly lower than those of the control groups (p < 0.05). The burst swimming ability did not seem to be affected by starvation time. Although the short-term starvation would not increase the young fish’s predation on shrimp, it might be serviceable for improving their feeding vitality. These behavioral results would help us understand the adaptive processes and response mechanisms of fish under starvation.

Assessing safety, efficacy and residue depletion in golden mahseer, Tor putitora (Hamilton, 1822): biochemical and physiological responses to graded concentrations of oxytetracycline dietary supplementation.

The safety and effectiveness of oxytetracycline can potentially manage bacterial infections in fish. This, in turn, might reduce the concerns related to its use in aquaculture and human consumption, such as toxicity, antimicrobial resistance, and other associated risks. The primary objective of this study was to assess how adding oxytetracycline dihydrate to the diet affects its effectiveness, safety, and the presence of residues in T. putitora. T. putitora fingerlings, subjected to experimental infection with Aeromonas hydrophila at a concentration of 108 CFU mL- 1, received an oral administration of oxytetracycline dihydrate. The oxytetracycline dihydrate was added to the feed (corresponding to 2% of the fish body weight) at concentrations of 44.1, 88.2, 132.3 and 176.4mg Kg- 1 fish body weight per day. This treatment was carried out for 10 consecutive days. The biochemical and physiological responses of T. putitora and efficacy of oxytetracycline dihydrate were determined through estimation of microbial load (CFU mL- 1), haematogram, serum biomarkers, behavioral characteristics, non-specific immunity and residue depletion. Experimentally infected fish showed disease progression and induced histopathological conditions with highest microbial load (CFU mL- 1) in the muscle of both control and treated fish. The fish haematogram showed increased leucocyte and haemoglobin content, influenced by dietary oxytetracycline dihydrate. The fish demonstrated adaptive physiological response to oxytetracycline dihydrate at 44.1 to 88.2mg and resulted in increased albumin and globulin content. The serum-enzyme assay showed significant increase in aspartate aminotransferase (AST), alanine aminotransferase (ALT) and plasma alkaline phosphatase (ALP) activities in the test fish (< 0.05). Oxytetracycline dihydrate at 88.2 to 132.3mg Kg- 1 fish body weight per day recorded higher feed intake (75%), significant survivability (66-68%) and histopathological recovery. The suppressed immune response was manifested with decreased respiratory burst and lysozyme activity. The palatability, treatment of bacterial infection, histopathological changes and survivability by fingerlings of golden mahseer determined the safety and optimized the therapeutic potential of the oxytetracycline dihydrate at 88.2mg Kg- 1 fish body weight per day for 10 days to contain the infection by A. hydrophila. A withdrawal period of 8-d was recommended as oxytetracycline dihydrate concentration depleted below the legal maximum residue limit (MRL 2.0 mg g- 1) in the edible muscle of the golden mahseer reared at an average water temperature of 20°C. This is considered safe for human consumption.

Growth, Hematological Evaluation and Heavy Metal Bioaccumulation in Nile Tilapia (Oreochromis niloticus) from A Municipal Waste Landfill Reservoir

The aim of this study was to evaluate the growth performance, mortality rate, and blood profile of Cd-, Pb-and Cr-contaminated Nile tilapia from the Khon Kaen municipal waste landfill reservoir and compare the parameters with those of fish from unpolluted sites. Human bioaccumulation factor (BAF) determination was also performed. Thirty samples of Nile tilapia were taken from the Khon Kaen municipal waste landfill reservoir (CN) and from unpolluted (TN) ponds. Water and soil were collected from these sites, and tilapia muscle, gill, and liver were obtained for heavy metal evaluation. The Cd concentrations in the muscle, gill and liver were 0.003 ± 0.001, 0.006 ± 0.008, and 0.004 ± 0.003 mg/kg; the Pb concentrations were 0.078 ± 0.173, 0.880 ± 1.360 and 1.110 ± 1.862 mg/kg; and the Cr concentrations were 0.067 ± 0.135, 0.572 ± 1.098 and 0.636 ± 1.272 mg/kg, respectively. The total fish length, body weight and survival rate were significantly lower in the TN group (P &lt;0.05), and alanine aminotransferase and creatinine were significantly (P &lt;0.05) higher in the TN group. The hematocrit count of the TN group was also lower than that of the CN group but without a significant difference. The BAF ranged from 0.1-4.3, especially in the gills and liver, which are major heavy metal accumulation organs. Heavy metal contamination in landfill leachate negatively affects fish health and its production. Keywords: Aquaculture, Nile tilapia, Heavy metal, Pathology, Toxicity

Assessment of Full-Fat Tenebrio molitor as Feed Ingredient for Solea senegalensis: Effects on Growth Performance and Lipid Profile.

Tenebrio molitor (TM) is considered as one of the most promising protein sources for replacing fish meal in aquafeeds, among other things because it is rich in protein, a good source of micronutrients and has a low carbon footprint and land use. However, the main drawback of TM is its fatty acid profile, in particular its low content of n-3 PUFA. This study evaluates the effects of partially replacing plant or marine-derived with full-fat TM meal at two different levels on growth performance and lipid profiles of Senegalese sole (Solea senegalensis). For this purpose, a control diet (CTRL) and four experimental isoproteic (53%) and isolipidic (16%) diets were formulated containing 5 and 10% TM meal replacing mostly fish meal (FM5 and FM10), or 10 and 15% TM meal replacing mostly plant meal (PP10 and PP15). Fish (215 g) were fed at 1% of their body weight for 98 days. The final body weight of fish fed the experimental diets containing TM meal was not different from that of fish fed the CTRL diet (289 g). However, the inclusion of TM meal resulted in a gradual improvement in growth rate and feed efficiency in both cases (replacement of fish or plant meals), and significant differences in specific growth rate (SGR) were observed between fish fed the CTRL diet (SGR = 0.30% day-1) and those fed diets with the highest TM meal content (PP15; SGR = 0.35% day-1). The experimental groups did not show any differences in the protein content of the muscle (19.6% w/w). However, significant differences were observed in the total lipid content of the muscle, with the FM10, PP10, and PP15 groups having the lowest muscle lipid contents (2.2% ww). These fish also showed the lowest neutral lipid content in muscle (6.6% dw), but no differences were observed in the total phospholipid content (2.6% dw). Regarding the fatty acid profile, fish fed FM10, PP10 and PP15 had lower levels of linoleic acid (18:2n-6) and higher levels of oleic acid (18:1n-9) in liver and muscle compared to fish fed CTRL. However, no differences were found between fish fed CTRL and TM-based diets for docosahexaenoic acid (22:6n-3) and total n-3 PUFA in liver and muscle. In conclusion, our study demonstrated that full-fat TM inclusion up to 15% in S. senegalensis diets had no negative effects or even some positive effects on fish survival, growth performance, nutrient utilization and flesh quality.

Gill morphometrics of freshwater Tilapia zillii as an indicator of fish welfare

Tilapia zillii was used to examine the effect of environment on gill morphometric therefore to discover the probability of using gill morphometrics to measure welfare in wild fish. Thirty mature Tilapia zillii was collected from Lagoon of Ain-Ziyana in eastern of Benghazi city and the sizes of their gills were estimated. The gill respiratory surface area of Tilapia zillii reached from 851.31 mm² to 1929.32 mm² ̸ g of body weight. The connection among gill respiratory surface area and fish body weight was found to be highly significant (P= 0.001). The gill respiratory surface area of Tilapia zillii rise as the fish grows this may be since the gill filaments number, the secondary lamellae number and the surface area of secondary lamellae increases. Great gill surface area might support survival of Tilapia fish in oxygen-stressed. This recommends that the measure developed here could be possibly used as an guide of welfare in wild fish.

Smoltification, seawater performance, and maturation in Atlantic salmon (Salmo salar) fed different fat levels

IntroductionThe use of recirculating aquaculture systems (RAS) to produce Atlantic salmon smolts has resulted in exceptionally high fish growth rates. However, there are potential negative trade-offs between fast growth and key physiological processes, such as inadequate smoltification and early sexual maturation, which can both be linked to body energy reserves.MethodsThis study determined the effect of i) dietary fat levels on Atlantic salmon whole-body fat and fatty acids composition, growth performance and smoltification and ii) a previous dietary regime on seawater growth performance and male early sexual maturation. In freshwater RAS, salmon parr (~19g) were fed 3 fat levels (20, 24, and 28%) over a 14-week period at 12°C. Subsequently, in seawater flow-through systems, smolt (~96g) were fed a control diet (26%) for 12 weeks at 2 temperatures (12 and 16°C).ResultsDietary fat levels resulted in differences in k-factor, fish whole-body fat and fatty acids composition; the low fat diet resulted in fish with a 23% lower whole-body fat when compared to the other two dietary groups at the end of the freshwater phase. These differences in whole-body fat faded at the end of the seawater phase. During the freshwater phase, all three feeds resulted in a comparable growth performance and smoltification indicator values, including k-factor, gill Na+, K+-ATPase, blood serum chloride and smolt index score. In contrast, water temperature resulted in fish body weight differences, where groups reared at 16°C were larger than those reared at 12°C. Nevertheless, both temperature regimes supported a similar thermal growth coefficient. Smolts grown at 16°C showed a higher level of the sex steroids androstenedione compared to those at 12°C. However, 11-ketotestosterone and testosterone levels did not differ despite a trend for higher levels at 16°C. Furthermore, testis histology at the final sampling indicated that some individuals showed initial signs of maturation (stage 3).DiscussionIn conclusion, varying dietary fat levels (20 - 28%) during the freshwater phase did not influence smoltification or male early sexual maturation during the subsequent grow-out phase. However, a temperature increase from 12 to 16°C resulted in larger fish and appeared to stimulate early male maturation in some fish individuals.

Single nucleotide polymorphisms in the MRFs gene family associated with growth in Nile tilapia.

Muscle occupies most of the fish body, promoting the proliferation of fish muscle fibers can facilitate rapid growth and increase the body weight of fish. Some studiesSeveral previous suggest that Myogenic regulatory factors (MRFs) play an important role in the growth of fish. To investigate the association between the polymorphism of MRFs gene family and growth traits in Nile tilapia (Oreochromis niloticus), get more molecular markers for growth. Amplified the Nile tilapia MRFs family gene, including Myogenic determination 1 (Myod1), Myogenic determination 2 (Myod2), Myogenin (Myog), Myogenic factor 5 (Myf5), and Myogenic factor 6 (Myf6), single nucleotide polymorphism (SNP) were screened by Sanger sequencing. A total of 16 SNP loci were screened, including six for Myf5, six for Myf6, one for Myog, one for Myod1 and two for Myod2. The growth traits were analyzed in relation to these 16 SNP loci, and the results indicated significant associations between all 16 SNP loci and the growth traits (P < 0.05). The linkage disequilibrium analysis revealed that D1 and D2 diplotypes of Myf5 gene, E1, E2, E3 and E4 of Myf6 gene, and F1 diplotype of Myod2 gene were significantly associated with superior growth traits. There were 6, 6, 1, 1 and 2 growth-related molecular markers in Myf5, Myf6, Myog, Myod1 and Myod2 genes, respectively, which could be applied to the breeding of Nile tilapia.

First study on the metazoan parasite community of Crenicichla strigata (Cichliformes: Cichlidae).

This study provides the first report of metazoan parasites in Crenicichla strigata. From 31 hosts caught in the Jari River basin, in the eastern Amazon region of Brazil, a total of 1454 parasites were collected: Sciadicleithrum araguariensis, Sciadicleithrum joanae, Sciadicleithrum satanopercae, Posthodiplostomum sp., Genarchella genarchella, Contracaecum sp., Spirocamallanus peraccuratus, Acarina gen. sp. and Dolops geayi. However, the community was dominated by the three species of Sciadicleithrum (Monogenea) and there was similar presence of parasites in the larval and adult stages. The total prevalence was 100% and each of the hosts was parasitized by two or three species, which presented random dispersion. Brillouin diversity, parasite species richness, Berger-Parker dominance index and evenness were low. There was positive correlation between the abundance of Posthodiplostomum sp. the hosts' length, while the abundance of S. peraccuratus showed negative correlation with the body weight of fish. The abundance of S. araguariensis, S. joanae and S. satanopercae showed negative correlation with the hosts' length. The parasite community of C. strigata was characterized by low diversity, low richness, low intensity and low abundance of species.

EFFECT OF DIFFERENT SUPPLEMENTARY FEEDS ON THE GROWTH OF COMMON CARP (CYPRINUS CARPIO)

The present experiment was conducted in a rectangular aquarium for three months to evaluate the growth performance of common carp (Cyprinus carpio). Growth performance of Common Carp were studied under four different feed supplements i.e. Feed contained Rice and Wheat bran (CG), Fish meal (T1), Poultry meal (T2) and waste proteins (T3). These four different supplementary feed were supplied to fish which were kept in four different tanks at Aquarium (Fisheries Lab) in Zoology department UAJ and K Muzaffarabad, at the rate of 0.25 gm/per day. Initially, at the time of stocking, the morphometric characteristics, viz, average body weight and average body length was measured. After initiation of experiment, these morphometric characteristics as well as physico-chemical parameters (pH and water temperature) of the water were recorded on daily basis throughout the study period. Average Body weight of Common Carp was recorded as, 13.91±1.592, 10.88±0.617, 11.96±0.967, 10.841±0.725 gm under treatment T1, T2 and T3 and Control group respectively. The final body weight of fish in Control group and treatment groups showed that fish kept in T1 (P-Value=0.003) have gained the maximum body weight, while other treatment groups showed no significant statistical difference. Final Body Length of Common Carp was recorded as 7.44±0.169, 11.28±1.407, 8.031±0.473, 9.293±1.490cm under Control group, T1, T2 and T3, respectively. The final body length of fish in Control group and treatment groups showed that fish kept in T1 (P-Value = 0.001) gained more length followed by T3 (P-Value = 0.007). There is no significant statistical difference in Control group and T2. These results suggest that T1 containing the 30% wheat and rice bran supplementary diets can increase the fish maximum body weight and body length.

Ameliorative effect of dietary supplementation of kinnow peel powder on the health status of Cyprinus carpio (L.) fingerlings

An outdoor feeding trial (120 days) was carried out in FRP pools (1.5 × 1.0 × 0.75 m) to evaluate the efficacy of dietary incorporation of kinnow peel powder (KPP) on the health status of common carp (Cyprinus carpio L.) fingerlings. Healthy fingerlings (av. length 9.19 cm, and av. weight 10.51 g) were stocked in five feeding treatments @ 15 nos./tank following a complete randomized design with three replicates for each treatment and daily fed with five iso-proteinous experimental feeds containing KPP at 0 (KPP0), 0.5 (KPP1), 1.0 (KPP2), 1.50 (KPP3) and 2.0% (KPP4) inclusion levels @ 2% of fish body weight. The results demonstrated that the water quality parameters remained within the optimum/permissible limit for freshwater carps in all the treatments. Further, KPP supplementation improved the haematological indices (total erythrocyte count, total leucocyte count, haemoglobin and haematocrit) and immunological parameters (serum total protein, Albumin (A), globulin (G) and A: G ratio) of fish at all the inclusion levels in respect to control, while the best (P0.05) findings observed at 1.5% KPP inclusion level. Additionally, in comparison with the control group, KPP supplementation decreased the glucose, cholesterol, triglycerides, alanine aminotransferase, aspartate aminotransferase, lipid peroxidation level, being lowest (P0.05) in KPP3, while increased the superoxide dismutase activity and recorded highest (P0.05) in KPP3 group. The results revealed that KPP can be potentially utilized as health promoting natural feed additive at a 1.5 % inclusion level to improve the overall health condition of C. carpio fingerlings.

Analysis of biological factors on affecting the growth performance and water quality of biofloc aquaculture system for freshwater barramundi

Biofloc technology is used to improve water quality and fish growth performance of aquaculture. The purpose of this research is to analyse the biological factors on freshwater barramundi in biofloc aquaculture system. Three set of experiments with 3 biological factors were carried out for freshwater barramundi to analyse the water quality and to evaluate the cultivated fish growth performance under the application of biofloc technology for 10 weeks. The biological factors involved are stocking density, carbon-to-nitrogen ratio and feeding rate. The water quality parameters were monitored weekly while the growth indices will be determined at the end of the experiments. The results revealed that stocking density has insignificant effect on the water quality but essential affected the growth rate of the freshwater barramundi. The best growth rate is observed at lowest stocking studied (10 fish/m3). The biofloc technology aquaculture system with C:N ratio of 16:1 and lowest stocking density (10 fish/m3) produced the best water quality and growth performance. Meanwhile the compatible feeding rate for the juvenile freshwater barramundi was identified at rate of 1% of fish body weight with feeding frequency once or twice a day in order to control the water quality and produced good growth performance of the juvenile.

Productive Performance and Serum Biochemical Parameters of Nile Tilapia Fingerlings Fed on Different Dietary Carbohydrate: Protein Ratios with Biotin Supplementation

The current experiment evaluated the effects of different dietary carbohydrate: protein ratios (CHO: CP ratio) without or with biotin supplementation on the growth performance, body composition, serum biochemical parameters and intestinal morphology in Nile tilapia. Fingerlings were assigned to 6 treatments arranged as following; Group 1 (G1) fed the basal diet (BD) with a medium CHO: CP ratio (47:32); G2 with high CHO: CP ratio (57:21); G3 with low CHO: CP ratio (36:42); while G4, G5 and G6 had the same previous experimental design of the first 3 groups but with biotin supplementation (0.06 mg/kg diet). The growth performance was only assessed for the first 6 weeks, then the experiment continued to 4 months and ended by sampling for other parameters determined. Fish feeding on high CHO: CP ratio (57:21) significantly reduced the fish body weight, gain and feed intake (FI) (P ≤ 0.05), while improved the feed efficiency compared to the medium and low ratios. Biotin addition to the high or the medium ratios containing diets resulted in lower growth, increased FI and deteriorated the feed efficiency when compared to their control groups without biotin addition (P≤ 0.05). Different dietary CHO: CP ratios significantly altered tilapia body composition of nutrients (moisture, EE, and ash), serum parameters (glucose, triglyceride, LDL and VLDL) and the liver function enzymes (GPT and GOT) (P≤ 0.05). The relative mRNA expression of GHR and IGF was significantly upregulated in fish fed on the low and the high ratios containing diets respectively. In conclusion, feeding of the early fingerling of tilapia on the high CHO: CP ratio during the first 6 weeks of life resulted in lower growth, however, it showed a protein sparing effect. Supplementation of biotin (extra over the diet) was not recommended as it showed adverse effects on tilapia growth especially during the first periods of life, however it showed some beneficial effects on alleviating the high-dietary carbohydrate-induced effects. Feeding on medium CHO: CP ratio (47:32) or low ratio (36:42) would be recommended during the fry and early fingerling stage of tilapia while the high ratio (57:21) would be beneficial in the diet of late fingerlings or adult tilapia.

Water Quality in the Habitat of Sembilang Fish (Plotosus canius) in the Estuary of Langsa City

Sembilang Fish (Plotosus canius) is one of the fish found in estuarine waters, and it's quite popular with the community. Excessive fishing by the community causes the habitat of sembilang fish to be threatened to decrease. The purpose of this study was to determine the water quality and examine the environmental conditions of sembilang fish in the dry season and rainy season in the estuary waters of Langsa City as the basis for domestication. This study used a descriptive method by collecting water quality data at 3 research stations and collecting fish data that was taken from fishermen's catches in Langsa estuary waters. The results showed that the water quality parameters observed in the dry season and rainy season in the estuary were still in decent condition for the life and existence of sembilang fish. Season greatly affects the body weight of both male and female fish. In the dry season, the female weight ranges from 120–220 g and the male 120–240 g, while in the rainy season, the female weight ranges from 134-572 g and the male 136–260 g.

Domestication of Asian Redtail Catfish (Hemibagrus sp.) as an Effort to Preserve Local Fish at the Loka Ngrajek in Magelang, Central Java

The Baung fish (Hemibagrus sp.) were used in this research were the first domesticated breed of native fish from Elo river, Magelang, Central Java. The growth pattern of Baung fish is very important to know for management and spesies conservation. The aim of this research were to analyze the size distribution, growth patterns and condition factors of Baung fish as a basis for managing fish resources. The research was conducted in September 2023 at Loka Ngrajek Magelang, Central Java. The fish samples used were the result of first generation domestication which were cultived in concrete tanks for six months. The body weight of Baung fish ranged from 66 g to 330 g. The survival rate of Baung fish from 5-7 cm to 20-35 cm were 55 ± 2.7%, while when enlargement it reached 93 ± 3.6%. Loka Ngrajek succeeded in domestication and produced the first generation with daily fish growth of 2.65 ± 0.11%. Cultivated fish have a length-weight relationship model W = 0.0104X2.9414, which showed negative allometric meaning that the increase in length was faster than the increase in weight.