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This study investigated the dietary immunomodulatory effects of Terminalia arjuna bark powder (TABP) in Labeo rohita, a freshwater fish model. Four iso-nitrogenous and iso-caloric diets containing graded levels of TABP (0, 1, 10, and 15 g/kg were fed to fish for 90 days, followed by a 10 day challenge with pathogenic bacteria Aeromonas hydrophila and Edwardsiella tarda. An integrated biomarker response (IBR) approach assessed the impact of TABP on hematological, adaptive, and humoral immune parameters, along with liver histomorphology. Dietary TABP at 10 g/kg significantly enhanced (p < 0.05) hematological indices (hemoglobin, red blood cell count, hematocrit), specific immune parameters (lysosomal enzyme activity, phagocytosis, respiratory burst), and non-specific immune parameters (serum lysozyme, alternative complement activity), and exhibited improvements in liver architecture consistent with the enhanced immune response. Broken line regression analysis showed 11.5 g/kg to be an optimum dose. However, at 15 g/kg, a compromised trend was observed in some parameters. These findings suggest an optimal dosage range for TABP's immunomodulatory effects. The study highlights the potential of TABP as a natural immunomodulator in fish aquaculture. The improved immune response and concomitant liver health observed in Labeo rohita opens avenues for further research on TABP's applicability in animal health, using fish as a model organism. Additionally, the IBR approach proved effective in evaluating TABP's immunomodulatory properties, paving the way for similar studies on other natural products in aquaculture. [ABSTRACT FROM AUTHOR]

Simple Summary: It is widely believed that aquaculture has the greatest potential to provide both economic and nutritional security. Bacterial infections in the culture system result from intensified aquaculture methods, resulting in a significant economic loss for fishermen. Because antibiotics are the standard treatment for bacterial infections in Southeastern countries, antimicrobial resistance has emerged as a major health concern. Herbal remedies are being promoted as a replacement for the undesired medicines. In Ayurveda, the Terminalia arjuna plant is considered a "miracle plant" since it has been used for centuries to treat serious illnesses in humans. However, applications in aquaculture remain in their early stage. The purpose of this study is to assess the therapeutic value of incorporating powdered Terminalia arjuna bark with Labeo rohita. Based on the findings, the researchers suggest adding Terminalia arjuna bark powder to fish food at a rate of 12.3 g·kg−1 (as determined by the broken line regression equation) to help the fish become resistant to disease. Utilizing agro-industrial waste and herbal products to create a circular bioeconomy is becoming increasingly popular. Terminalia arjuna is a significant ethnomedicinal plant that has not yet been exploited in animal feed. In the present study, nutritional Terminalia arjuna bark powder-based fish feed was created and supplied to a candidate fish species Labeo rohita at varied levels: 0% (0 g/kg), 0.5% (5 g/kg), 1% (10 g/kg), and 1.5% (15 g/kg). These treatment groups are denoted as CT, T1, T2, and T3, respectively. Utilizing a contemporary comprehensive biomarker response strategy, the study clarified the genomic influence of dietary herb inclusion. In response to bacterial infection, the immunogenic genes, STAT 1 (signal transducer and activator of transcription 1), ISG 15 (interferon stimulating gene), and Mx "myxovirus resistance gene", were shown to be elevated. The results of densitometry demonstrated a dose-dependent increase in STAT 1 and ISG 15, with Mx exhibiting maximal values at 1 g/kg TABP (Terminalia arjuna bark powder-based feed). This is the first study to identify TABP as an immunomodulator in fish and established the IBR (Integrated Bio-marker Response) as a reliable marker in evaluating the impact of multiple drivers in a holistic manner. Thus, the present study cleared the path for TABP to be utilized as an effective feed additive which enhances the specific adaptive immune system of the fish for the production of the Green fish product for a sustainable circular bioeconomy. [ABSTRACT FROM AUTHOR]

Asian catfish, Clarias magur (Hamilton, 1822), known as magur, is a popular food fish in Asian countries because of its high nutritional and medicinal value. Aquaculture of magur is constrained by non‐availability of seed due to very high mortality during the early larval stages. The strategies to enhance the larval survival during the early stages could be a major step in enhancing the seed production of this species. So, the aim of the present study was to assess the effect of highly unsaturated fatty acids (HUFA)‐ and vitamin C‐enriched infusoria on the growth and survival of C. magur larvae. Eight‐day‐old larvae with an average weight of 3 mg and length of 5 mm were stocked in plastic crates (30 x 20 x 18 cm) each containing 40 litres of water. A total of 16 crates were used in experiment and in each crate 100 larvae were stocked. The larvae were fed three times daily with HUFA, vitamin C, both HUFA and vitamin C and un‐enriched infusoria @ 9–10 numbers per ml of rearing water for 30 days in four different treatment groups. The proximate analysis of different enriched and un‐enriched infusoria showed the highest (84.25%) moisture content in HUFA‐enriched Infusoria, and the highest percentage of crude protein (9.80%), crude lipid (3.50%) and ash content (0.78%) in vitamin C‐enriched Infusoria. The survivability analysis showed the highest survival in the treatment group fed with HUFA‐enriched infusoria (49.25%) and the lowest in the control group (18.25%). This indicates that the enrichment of infusoria with HUFA could increase the survival rate significantly. The highest body weight gain (55.75 mg) was observed in HUFA‐enriched group but not significantly different from the control group. The study indicates that the enrichment of infusoria with HUFA have a significant influence on larval survival. [ABSTRACT FROM AUTHOR]

A 60-day feeding trial was conducted to examine the effect and interaction of dietary ractopamine hydrochloride (Rac) supplementation in diets with varied levels of protein and lipid for L. calbasu fingerlings. To attain this, the fish body compositions, digestive and metabolic enzyme activity were assessed. In total, nine diets were fed in triplicates to four hundred and five healthy Calbasu, Labeo calbasu fingerlings, based on ractopamine supplementation, viz., control (0 mg/kg), T1 (10 mg/kg), and T2 (20 mg/kg). The diets were further assigned in different levels of protein and lipid, viz., 35% protein and 6% lipid, 30% protein and 9% lipid, and 25% protein and 12% lipid. At the end of the trial, it has been observed that the inclusion of ractopamine hydrochloride at 20 mg/kg-1 of basal diet significantly (p < 0.05) improved the protein content in fed fish compared to the control. In addition, metabolic enzyme activity for hexokinase, glucose-6-phosphate, and glucose-6-phosphate dehydrogenase along with aspartate amino transferase and alanine amino transferase activity were significantly (p < 0.05) improved with the inclusion of 20 mg/kg ractopamine hydrochloride. However, the supplementation of ractopamine hydrochloride does not improve (p > 0.05) digestive enzyme activity, viz., amylase, lipase, and protease activity in the fed fish. Conclusively, it implies that adding ractopamine hydrochloride at 20 mg/kg of basal diet (high and low protein content) enhances the whole-body protein content and improves the metabolic enzyme activity in L. calbasu fingerlings. Hence, ractopamine hydrochloride has a beneficial effect in L. calbasu fingerlings and would be a desirable feed supplement for this new species culture system. [ABSTRACT FROM AUTHOR]

The present research was conducted to prepare efficient G‐SPIONs by co‐precipitation to remove Edwardsiella tarda and Aeromonas hydrophila from the aqueous solution. The synthesized G‐SPIONs were characterized by UV–Vis spectrophotometer, DLS, FEG‐TEM, FT‐IR, XRD, and VSM analysis. The results showed that the synthesized G‐SPIONs had super‐paramagnetic properties (58.31 emu/g) and spherical shape (16 ± 3 nm). The antibacterial activity was assessed in sterilized distilled water at different G‐SPIONs concentrations viz. 0, 1.5, 3, 6, 12, 24, 48, 120, and 240 mg/L against E. tarda and A. hydrophila with various bacterial loads viz. 1 × 103, 1 × 104, 1 × 105, 1 × 106, and 1 × 107 CFU/ml at different time intervals 15, 30, 45, and 60 min. At a lower bacterial load of E. tarda and A. hydrophila 1 × 103–1 × 104 CFU/ml, 100% bacterial load was removed by 15 min exposure with NPs concentration 6–48 mg/L and 1.5–6 mg/L, respectively. Cent percent bacterial removal was observed in both the bacterial species even at higher bacterial load (1 × 105–1 × 107 CFU/ml) by increasing exposure time (15–60 min) and nanoparticle concentration as well (24–240 mg/L). At an initial bacterial load of E. tarda and A. hydrophila (1 × 103–1 × 107 CFU/ml), the EC50 ranged between 0.01–6.51 mg/L and 0.02–3.84 mg/L, respectively, after 15–60 min exposure. Thus, it is concluded that the antibacterial effect of G‐SPIONs depends on concentration and exposure time. Hence, G‐SPIONs can be used as an antibacterial/biocidal agent to treat Edwardsiellosis and Aeromonosis disease in aquaculture. Highlights: The glucose‐conjugated super‐paramagnetic iron oxide nanoparticles (G‐SPIONs) synthesized by rapid and high yield co‐precipitation method shows bacterial removal efficiency against Edwardsiella tarda and Aeromonas hydrophilaThe bacterial removal efficiency of G‐SPIONs depends on concentration and exposure time to both the bacterial speciesThe 100% bacterial removal efficiency can be achieved even at the highest bacterial load (1 × 107 CFU/ml) against E. tarda and A. hydrophila after 45 and 30 min exposureDue to the high bacterial removal efficiency of G‐SPIONs against E. tarda and A. hydrophila, it can be used for the treatment of Edwardsiellosis and Aeromonosis in fish [ABSTRACT FROM AUTHOR]

The study determined the combined effect of dietary l‐carnitine (non‐essential organic nutrient) and ractopamine (feed additive) on growth performance and nutritional composition of Labeo calbasu. To ascertain this, a 60‐day feeding trial was carried out under a controlled condition where two hundred and twenty‐five healthy L. calbasu fingerlings (avg. wt. 3.47 ± 0.1 g) were divided into four treatments group and one control group in triplicate. Therefore, the respective combination of l‐carnitine and ractopamine diet was fed to L. calbasu fingerlings as C: control or basal feed without l‐carnitine and ractopamine; T1:1 g kg−1l‐carnitine and 10 mg kg−1 ractopamine; T2: 2 g kg−1l‐carnitine and 20 mg kg−1 ractopamine; T3: 3 g kg−1l‐carnitine and 30 mg kg−1 ractopamine and T4: 4 g kg−1l‐carnitine and 40 mg kg−1 ractopamine, respectively. Upon completion of the 60‐day feeding experiment, eight fish were randomly collected from each tank and subjected to a series of laboratory analyses. The study determines that T2 group fish significantly (p <.05) improved the WGP (244.66 ± 20.59%), SGR (0.89 ± 0.04), PER (2.20 ± 0.14) and increased crude protein content in fish muscle. In addition, many essential amino acids were recorded significantly high (p <.05) in the fish fed with diet T2 compared with others. Hence, dietary supplementation of l‐carnitine and ractopamine at 2 g kg−1 and 20 mg kg−1 in combination is beneficial for growth and nutritional composition of L. calbasu. [ABSTRACT FROM AUTHOR]

A 60-day feeding experiment was conducted to evaluate the dietary effect of vitamin C on non-specific immunity and stress responses in striped catfish, Pangasianodon hypophthalmus juveniles with the average body weight of 3.23 ± 0.01 g to 3.38 ± 0.01 g. Seven graded levels of diets supplemented with 0, 17.5, 35, 70, 175, 350 and 700 mg vitamin C/kg diet as L-ascorbyl-2-polyphosphate were fed to fish in triplicates group. At the end of the experiment, fish fed vitamin C diet had significantly higher responses for nitroblue tetrazolium (NBT), serum lysozyme, phagocytic activities and lowest activities for superoxide dismutase (SOD) and catalase (p<0.05) under both pre- and post-challenge conditions with Aeromonas hydrophila. After a challenge, the percentage survival of fish fed vitamin C diet was improved than those of fish fed vitamin C-deficient diet. The overall results of the present study indicated that dietary vitamin C had a significant influence on immunity and stress mitigation in P. hypophthalmus juveniles. However, the highest positive response values obtained for immune and stress parameters in fish lies within the range of 350 to 700 mg ascorbic acid (AA) kg-1 of the diet. From the present experiment, it may be concluded that the dietary vitamin C supplementation at the level of 350 to 700 mg AA kg-1 of the diet would be optimal for influencing the immunity and stress responses in P. hypophthalmus juveniles. [ABSTRACT FROM AUTHOR]

A 15‐day trial was conducted to determine the effect of dietary potassium on the requirement of aqueous potassium in P. vannamei under inland saline water (ISW). Two experimental diets viz. control (C) and control with 1% KCl (K) were fed to P. vannamei as six treatments viz. FW (reared in freshwater and fed on C), ASW (reared in artificial seawater and fed on C), ISW (reared in inland saline water and fed on C), ISW+eK (reared in potassium fortified ISW and fed on C), ISW+fK (reared in ISW and fed on K) and ISW+½eK+fK (reared in 50% K fortified ISW and fed on K). The samples were collected on selected intervals (0th day, 1st day, 7th day and 15th day), and mortality was recorded continuously. Total mortality (100%) was observed in FW and ISW. 100% survival was recorded in ASW and ISW+½eK+fK, while a lower survival was observed in ISW+fk. The haemolymph osmotic and ionic concentrations were lowest in FW and ISW. The principal ions (Na+, K+ and Cl−) and osmolality of ISW+½ eK+fK were restored to the level of ASW within 15 days. Na+K+ATPase activity was increased in ISW while lowered by K supplementation. HSP70 expression was upregulated in ISW fortified with K partially or entirely. However, the groups reared in ISW and ISW supplemented with feed potassium alone could not enhance HSP protection up to the level of ISW+eK and ISW+½ eK+fK groups. Overall, 50% of aqueous potassium can be compensated with 1% dietary KCl, without affecting survival and ionic homeostasis. [ABSTRACT FROM AUTHOR]

Green pea, Pisum sativum leaf meal (PSLM) was evaluated by conducting a 60‐day feeding trial in the diet of Labeo rohita fingerlings. Six iso‐nitrogenous (310 g CP/kg) and isocaloric (14 MJ DE/kg) diets viz. Control (0 g PSLM/kg), LM150 (150 g PSLM/kg), LM300 (300 g PSLM/kg), CCX (control + 1 g cellulase and xylanase, CX mixture/kg), LM150CX (LM150 + 1 g CX/kg) and LM300CX (LM300 + 1 g CX/kg) were prepared. Two hundred and seventy acclimated fish (5.06 ± 0.08 g) were randomly distributed in six experimental groups in triplicate with the stocking density of 15 fish per tank and the fish of each experimental tank were fed with respective diet at satiation level. The specific growth rate, protein efficiency ratio, apparent dry matter digestibility coefficient, amylase activity and the activities of muscle aspartate aminotransferase and alanine aminotransferase of LM150CX group were the highest among the experimental groups. However, LM300CX and control groups exhibited significantly higher (p < 0.05) values of these parameters than other groups except LM150CX group. Hepatic catalase and superoxide dismutase activities of LM150CX group were the lowest. Moreover, LM300CX and control groups showed significantly lower (p < 0.05) activities of these enzymes than other dietary groups except LM150CX group. The groups fed with leaf meal and exogenous enzyme showed enhanced hepatic IGF‐1 expression. In conclusion, dietary inclusion of PSLM at 300 g/kg with supplementation of CX (1:1) at 1 g/kg could replace DORB completely in the diet of L. rohita without compromising the growth performance. [ABSTRACT FROM AUTHOR]

The availability of zinc has been correlated with reproductive performance. To validate the hypothesis, a 60‐day feeding trial was conducted to evaluate the effect of dietary zinc on reproductive performance and gonadotropin gene (FSH and LH) expression in threatened Clarias magur brooder. Four isonitrogenous (35%) and iso‐energetic (372.18 ± 1.73 k cal/100 g) diets were prepared with zinc acetate as control (100 mg/kg diet normal requirement), T1 (50 mg/kg diet, low zinc), T2 (200 mg/kg diet, medium zinc) and T3 (300 mg/kg diet, high zinc). The weight gain % and specific growth rate were significantly (p < 0.05) decreased with the increased dietary zinc level. The pituitary mRNA levels of FSH were assessed during the reproductive cycle of female C. magur, and the FSH expression was increased which was significantly (p < 0.05) highest in T1 group. Similarly, LH expression was revealed to be highest. In all treatment groups except T1, GTH expression reduced significantly by increasing zinc inclusion in the diet. GSI and fecundity were lowest during initial sampling and start to increase was observed. The highest GSI and fecundity were recorded in the T1; however, GSI and fecundity significantly (p < 0.05) reduced with increasing the zinc level. Reproductive parameters like spawning fecundity, fertilization rate, hatching rate and larval survival were found to be dose‐dependent of zinc. This revealed that 50 mg/kg zinc was optimum for enhanced reproductive performance; therefore, the present study proposed that 50 mg/kg of zinc could be supplemented for flexible enhanced reproductive performance in threatened Asian catfish, C. magur. [ABSTRACT FROM AUTHOR]

A feeding trial was conducted with inclusion levels of Cajanus cajan leafmeal (CCLM) in the diet of Labeo rohita to study the growth, haematological indices, digestive enzyme, physio‐metabolic changes and molecular expression of insulin‐like growth factor‐1 (IGF‐1), insulin‐like growth factor‐binding protein‐1 (IGFBP‐1), insulin‐like growth factor‐1 receptor (IGF‐1R) genes. Four practical diets with CCLM, control, T20 (20%), T30 (30%) and T40 (40%) were prepared. Weight gain%, SGR, FER and PER were significantly (p < 0.05) higher when 30% de‐oiled rice bran (DORB) was replaced by CCLM whereas the treatment group 40% registered with lower FCR value. The protease and amylase activities were higher in the T30 group. T20 showed significantly higher (p < 0.05) hepatic and muscular lactate dehydrogenase and serum glucose was also higher, whereas, WBC content was found significantly (p < 0.05) higher in control. The hepatic IGF‐1 gene expression was significantly higher (p < 0.05) in T40 followed by the T30 group but the weight gain was not significantly (p > 0.05) higher in T30 from the T40 group. Results reveal that the response of IGF‐1, IGF‐1R and IGFBP‐1 genes was complementary to the biological growth parameters and hence were used as an indicator to evaluating growth. The study also demonstrates that CCLM can replace 100% DORB in the diet of L. rohita without any antinutritional or adverse growth effects. [ABSTRACT FROM AUTHOR]

A 60‐d experimental trial was conducted to evaluate the effects of alternative feeding, restriction feeding, and refeeding on digestive enzymes, metabolic enzymes, and metabolites in Rohu Labeo rohita fingerlings. Fish weighing around 13 ± 2 g were randomly distributed into four treatment groups and a control group. The control group was fed with 3% body mass twice a day throughout the experiment. The four treatment groups consisted of T1 (alternate day feeding), T2 (0.5% feeding), T3 (1% feeding), and T4 (2% feeding). The fish were fed for the first 30 d according to the feeding schedule, and from day 31 onwards all of the treatment groups were fed the same rations as were the control fish up to 60 d. The samples were collected on days 0, 15, 30, 45, and 60 of the experimental trial. The activity of digestive enzymes decreased significantly (P < 0.05) in T1, T2, and T3 with respect to the control, and the lowest activities were found on day 30 of the experiment. The glucose‐6‐phospahate dehydrogenase activity decreased with the level of restriction feeding, with the lowest activity occurring at day 30 in the T2 group, and it improved with refeeding. The serum glucose, triglycerides, and cholesterol concentrations decreased, with the lowest levels occurring in the T2 group at day 30. The current study revealed that restriction feeding and refeeding affected the digestion and metabolism of Rohu fingerlings within a short period of 30 d, and refeeding restored the optimum activity levels within the same 30‐d period thereafter. [ABSTRACT FROM AUTHOR]

An experiment was carried to determine the plasma fenbendazole (FBZ) concentration and physio‐metabolic responses in juveniles of Labeo rohita (90 ± 4 g) after oral administration of single doses at 10, 20 and 50 mg, 20 mg FBZ/kg b.wt. in multiple times on 1st, 3rd and 7th day. The blood samples were collected at 0.5, 1, 2, 4, 8, 12, 24, 30, 48, 72, 96 and 120 hr, after single‐dose administration, and regularly (upto 15 day) in multiple dose. Plasma FBZ concentration was determined up to the limit of detection (LoD) of 0.09 µg/ml by HPLC. There was no parent drug detected in plasma for administration of 10 mg FBZ/kg b.wt. The drug attained the peak concentration (Cmax) 1.85 and 3.09 µg/ml in plasma at 4 hr (Tmax) after administration of 20 and 50mg FBZ/kg b.wt. respectively. Plasma FBZ was detectable up to 96 and 120 hr with concentration 0.09 ± 0.007 and 0.098 ± 0.006 µg/ml, respectively, after single‐dose administration of 20 and 50mg/kg b.wt. In case of multiple‐dose administration, the maximum concentration of FBZ was 1.01 ± 0.03 µg/ml on 7th day that was less than to the single dose at 50 mg/kg b.wt. However, FBZ was detected up to 11 day after multiple doses. The study revealed that the hepatic antioxidant enzymes activities like superoxide dismutase, catalase and glutathione‐S‐transferase were significantly affected by increasing FBZ in single and multiple doses. The results of the present study could reveal that single‐ or multiple‐oral administration of FBZ at 20 mg/kg b.wt. in feed as antihelminthic drug in L. rohita could be considered as the safe dose. [ABSTRACT FROM AUTHOR]

This study assessed the responses of vitamin-D 3 intraperitoneally injected to Rohu, Labeo rohita @ of 0 IU/kg bw (only solvent), 100 IU/kg bw and 500 IU/kg bw reared in 20 and 40 ppm of calcium (Ca) enriched water. The cellular changes in Corpuscles of Stannius (CS) gland, serum Ca, and inorganic phosphate (P i) level were analysed up to the 60th day. Rohu administered with 100 IU/kg bw D 3 and exposed to 40 ppm Ca-rich water exhibited notable hyperplasia of CS compared with their control groups. Notable changes with high serum Ca level (13.87 ± 0.3 mg/dl) was detected on the 5th day in fish exposed to 40 ppm Ca-rich water, while related values attained (13.74 ± 0.1 mg/dl) only after 7 days in 20 ppm Ca-rich water of 500 IU/kg bw vitamin D 3 injection. Similarly, high serum P i level (7.66 ± 0.2 mg/dl) in 40 ppm Ca injected with D 3 at 500 IU/kg bw. The results demonstrated that the Ca homeostasis of Labeo rohita is influenced by intra-peritoneal vitamin D 3. Progressive studies should be conducted by increasing the dose of vitamin D 3 to investigate optimum dose/supplement in feed for commercially important aquaculture teleost Labeo rohita for maximum and sustainable absorption of Ca from the variable water Calcium levels to maintain Ca2+ homeostasis. [ABSTRACT FROM AUTHOR]

The present study was an attempt to perform functional screening and evaluating the effects of solvent extracts of Terminalia arjuna against Argulus bengalensis. Solvent extracts were used at 10, 20, 30, 40, and 50 mg/L, at 1, 2, 3, 4 and 5 hours and 12, 24, 36,48 and 60 hours under in-vitro and invivo conditions, respectively in moderately parasitically challenged (25-30, A. bengalensis/fish) Labeo rohita juveniles of 30±1.5 g. The 5% dimethyl sulphoxide was used as negative control (DMSO). The LC50 values of solvent extracts for L. rohita were 67.67±12.59, 78.13±14.17, 79.12±17.68, 156.47±12.67 and 256.43±8.93 mg/L for Terminalia arjuna ethanolic bark extract, Terminalia arjuna methanolic bark extract and Terminalia arjuna acetone bark extract, respectively, at 60 hours interval. Under invitro condition, 100% anti-parasitic efficacy (AE) and minimum therapeutic index (TI) value (1.2) was ascertained by Terminalia arjuna ethanolic bark extract at 50 mg/L in 2 hour, and minimum LC50 was reported by Terminalia arjuna ethanolic bark extract under in-vitro condition (13.14±3.79 mg/L) and maximum by Terminalia arjuna acetone bark extract under in-vitro condition (75.8±12.69 mg/L) at 5 hour interval. While, under in-vivo conditions, minimum LC50 for immersion and bath treatments was observed with Terminalia arjuna ethanolic bark extract (27.92±9.56 mg/L) and TAEBIM (33.6±7.58 mg/L), correspondingly, at 60 hours. The minimum TI was reported in bath treatment of Terminalia arjuna ethanolic bark extract (1.1). The RPS was also improved in bath treatment as compare to the immersion treatment. The 100% anti-parasitic activity was observed in bath treatment of Terminalia arjuna ethanolic bark extract at 24 hours. The PCA bi-plot explains 79.34% and 14.32% variations for component 1 & 2, respectively. The efficacy of solvent extracts varied significantly in response to concentrations of the extracts and exposure times and toxicity of the extracts (Exposure time*extract *treatment: F=16.12, P= 0.04). The study provides, the evidences for safe and effective application of prospective solvent extracts of T. arjuna against A. bengalensis in L. rohita juveniles, and yield first-hand information on acute toxicity of solvent extract in L. rohita. [ABSTRACT FROM AUTHOR]

Transportation of live fish is an inevitable process of aquaculture, whether it may be for the trading of ornamental fishes or for availing seeds in grow-out culture ponds. Netting, grading, handling, water movement and variation in water quality parameters cause severe stress to the fishes during transportation, which ultimately leads to physiological disturbance and mortality in the transported fishes. For maintaining optimum physiological balance during transportation of commercially important fish species, the use of different types of water additives is being promoted and being available in the market. Therefore, a holistic review on the application of different types of water additives is required in order to explore their effect during fish transportation. [ABSTRACT FROM AUTHOR]

Transportation of fish seed generally causes stress and mortality in the commercially important species. The objective of the present study is to investigate the stress eliminating capacity of a selected water additive on the transportation of L. rohita fingerlings based on primary and secondary stress response. By using glucose and sodium chloride in different combinations, the experiment was set up four treatments (T1 - 1g Glucose +2g sodium chloride, T2 - 2g Glucose+ 2g Sodium chloride, T3 - 1g Glucose + 4g Sodium chloride, T4 -2g Glucose + 4g Sodium chloride) and a control in triplicate. Simulated transportation of L. rohita was done for 12 h and sampling was carried out in various intervals viz. before transportation (0 h), immediately after transportation (1st day) and on 36th h (2nd day), 168th h (7th day) post transportation. Cumulative survivability data was also monitored in each treatment and control up to 7 days post transportation. A significant increase in serum cortisol, creatinine, triglyceride, SGPT activity was observed in control group in comparison to treatment groups on each sampling day. Further the tissue metabolic enzymes such as MDH, LDH and G-6 phosphatase also found to be higher in control in comparison to the treatment groups. The result of the present study shows that the combinatorial dose of 1g/L glucose and 4g/L NaCl could curtail the stress response and highest cumulative survival in transported rohu fingerlings. [ABSTRACT FROM AUTHOR]

A feeding trial was conducted to evaluate the effect of inclusion of Sesbania leaf meal in the diet of Cyprinus carpio as a replacer of de‐oiled rice bran (DORB). Bacillus subtilis was used to ferment the Sesbania leaf meal (SLM) to produce FSLM (fermented sesbania leaf meal). Fishes were fed with five isonitrogenous (30% CP) and isocaloric diets for 60 days and treatments were viz., C (30% DORB, 0% SLM), R15 (15% DORB, 15% SLM), R30 (0% DORB, 30% SLM), F15 (15% DORB, 15%FSLM) and F30 (0% DORB, 30% FSLM) by replacing DORB with SLM. A similar growth performance with control was observed in 15% FSLM group while there was a growth reduction in all the raw leaf meal fed groups. Similarly, the expression of insulin‐like growth factor‐1 (IGF‐1) was significantly (p <.05) higher in control and 15% FSLM fed groups. Growth and metabolic enzymes such as protease, amylase, ALT and AST activities were significantly higher in the fermented leaf meal fed groups compared to their non‐fermented counterparts. Antioxidant enzymes, serum transaminase enzymes (SGOT, SGPT) and total bilirubin (TBR) were found to be increased by enhanced level of RSLM, however, reduced by inclusion of FSLM. However, 30% inclusion level of FSLM even after fermentation showed detrimental effect on growth and metabolic response at cellular and molecular level. Thus, the results concluded that fermented Sesbania leaf meal (FSLM) using B. subtilis could replace 50% DORB (15% FSLM group) in the diet of C. carpio without affecting the growth and other physiological responses. [ABSTRACT FROM AUTHOR]

The study was conducted to investigate the efficacy and physio‐metabolic responses of single and multiple doses of fenbendazole (FBZ) in Labeo rohita against gill parasite (Dacylogyrus sp.). Two Isoenergetic (395 Kcal DE/100 g) and isonitrogenous (35% CP) purified diets viz. control (without FBZ) and treatment (0.2% FBZ) were prepared. The efficacy of FBZ was measured after administration of single dose (20 mg/kg b. wt.) on 0th day and multiple doses of FBZ, that is, 20 mg/kg b. wt. on 0th, 3rd and 7th day through diet. Although oral administration of FBZ at single dose could significantly reduce the parasite in fish in comparison with the control group, 100% efficacy of the drug was not achieved up to 15th day of treatment. On the other hand, multiple doses of FBZ could show almost 100% efficacy on 15th day in terms of elimination of parasites from gill. The drug induced oxidative stress in examined fish. There was no significant change in activities of hepatic and muscle aspartate aminotransferase and alanine aminotransferase of L. rohita up to 15th day after oral administration of FBZ at single dose. But both single and multiple doses of FBZ could significantly enhance the hepatic superoxide dismutase, catalase and glutathione‐S‐transferase activities in fish up to 7th day of drug administration and significantly decreased thereafter up to 15th and/or 30th day. It is concluded that oral administration of FBZ at multiple doses (20 mg/kg b. wt.) on 1st, 3rd and 7th day could be effective against Dactylogyrus sp. infection in L. rohita. [ABSTRACT FROM AUTHOR]

Ghrelin is a peptide hormone secreted primarily by the stomach and is involved in controlling growth by governing different functions in vertebrates including feed intake and metabolism in vertebrates. This work was aimed to identify sequences of ghrelin gene and growth hormone secretagogue receptor (GHSR) in Labeo rohita. The full-length cDNA sequence of ghrelin is 453 bp including 5′-untranslated region (UTR) of 65 bp, 3′-UTR of 76 bp with a poly-A frame. An open reading frame (ORF) is 312 bp, which encodes a peptide of 103 amino acid residues. A secondary structure of GHSR protein consists of alpha helix 66.0%, 16% disordered and 43% transmembrane helix. Molecular docking and interaction between synthetic ghrelin peptides and GHSR in the contact map revealed 19 amino acid residues closer than 4.5 Å distance. The mRNA expression level of ghrelin, leptin, GHSR, growth hormone releasing hormone (GHRH) and insulin growth factor-I (IGF-1) revealed significant changes (p < 0.05), in the different treatments. The outcome of the present work contributes to understanding the role of ghrelin and its mechanism of action in regulating the expression of growth-related genes and feed intake in fish. [ABSTRACT FROM AUTHOR]

Background/Aims: The growth promoting effect of lysine and betaine as well as the expression of candidate genes reflecting their efficacy, such as ghrelin, leptin, Growth Hormone Secretagogue Receptor (GHS-R), Insulin like Growth Factor (IGF- 1) and Growth Hormone Releasing Hormone (GHRH) was examined in Labeo rohita fingerlings. Methods: One hundred eighty healthy juveniles from a homologous population were randomly distributed to 15 rectangular tanks of 150 litres capacity. The experiment was carried out for 60 days with five treatment groups consisting T1 (0.25% Betaine), T2 (0.5% Betaine), T3 (0.75% Lysine) and T4 (1.5% Lysine) and control group.  At the end of trial, the growth parameters such as weight gain, SGR, PER were estimated from the weight of the triplicate groups. The digestive, metabolic and antioxidant enzymes were analysed using spectrophotometric methods. The intestine, brain and liver were sampled from the treatments and expression of different genes ghrelin, leptin, GHSR, IGF-1 and GHRH was also performed by realtime PCR. Results: A significant (P<0.05) increase in weight gain, SGR, PER and lowest FCR was found in T4 group which was significantly (p < 0.05) different from other experimental groups. The highest mRNA expression levels of expression were found in T4 group which was similar to that of ghrelin gene mRNA of T2 group. The significantly (p<0.05) highest GHSR, GHRH and IGF-1 gene expression levels were found in T4 treatment group compared to other groups. Conclusion: The present study reveals that the lysine and betaine stimulate growth and expression of ghrelin GHRH, GHS-R and IGF-1 genes. The increase of IGF-I mRNA expression with lysine and betaine supplementation revealed that these compounds act as growth modulators. However, lysine was found to be a more potent modulator of growth compared to betaine. [ABSTRACT FROM AUTHOR]

A 60-days feeding trial was conducted to evaluate the effects of different protein and carbohydrate ratios in the diet of Magur (Clarias magur) fingerling (Average weight 3.26±0.17 - 3.61±0.19 g). Six hetero-nitrogenous (150 - 400 g kg-1 crude protein (CP) and iso-energetic (19.0 -19.8 MJ kg-1 GE, gross energy) diets such as D1 (0 g kg-1 Starch and 40% CP), D2 (100 g kg-1 Starch, 35% protein), D3 (200 g kg-1 Starch, 30% CP), D4 (300 g kg-1 Starch, 25% CP), D5 (400 g kg-1 Starch, 20% CP) and D6 (500 g kg-1 Starch, 15% CP), were prepared and fed at 5% of body weight. Growth parameters; i.e. The weight gain, percent weight gain, SGR, among all the groups were decreasing significantly (P<0.05) from the highest protein to lowest protein fed group except D1 and D2 groups, simultaneously FCR found increasing. PER was highest in D6 (3.10), followed by D5 (2.88), D4 (2.49), D3 (2.32) D2 (2.17) and lowest in D1 (1.95). A cent percent survival was achieved in all the experimental groups. The activity of amylase has shown an increasing trend with increasing in carbohydrate levels while protease activity shown a decreasing trend on successive increase in carbohydrate levels. Lipase activity was significantly (P<0.05) increased in the groups with more than 60% starch inclusion in a dose-dependent manner. The study concluded that the C.magur can utilise carbohydrate up to 67%, however, it compromises growth and increased FCR. The significantly highest (P<0.05) protein deposition observed in the D2 diet (35% CP). Therefore 35% crude protein can be acceptable with 44% inclusion of carbohydrate. Thus the study suggests that ratio of protein and carbohydrate as 1:1.26 given optimum growth and better utilization of nutrients. [ABSTRACT FROM AUTHOR]

Abstract A short term starvation and refeeding experiment was conducted to study the temporal changes in SOD, CAT and HSP70 gene expression of Labeo rohita fingerlings. The study was carried out for 15 days with initial 7 days of starvation and then refeeding up to 15th day of the experimental trial. The expressions of SOD and CAT genes of liver and gills were significantly up-regulated after 7 days of starvation, down-regulated after 3 days of refeeding, and returned to the basal values after 8 days of refeeding. The HSP70 gene expression was significantly (p < 0.05) increased after starvation, with highest mRNA expression found on 7th day and reduced to the levels of control on refeeding. The activities of antioxidant enzymes, SOD and CAT were also studied to correlate with the results of gene expression. The changes in activities of SOD and CAT were found significantly (p < 0.05) higher in the starved group compared to the fed group. The dynamics of AST and ALT in serum revealed a progressive increase till the 7th day and decreased upon refeeding, cortisol level also has shown significant increase up to 7th day of starvation and sharp decline on refeeding. The concentration of blood glucose level start declining on 3rd day onwards with lowest level found on 7th day of starvation and was quickly restored to the levels of control on refeeding. The present study reveals that starvation elicits oxidative stress response as revealed by enhanced expression and activities of antioxidant enzymes, HSP 70 and serum biochemical alterations. However, these alterations were restored upon refeeding of L. rohita within 7 days. Highlights • The mRNA expression of SOD, Catalase and Hsp 70 were upregulated during starvation and downregulated on refeeding. • The antioxidant enzyme activities were significantly increased during starvation and declined during refeeding. • Cortisol, glucose, AST and ALT showed a significant response during starvation and refeeding. [ABSTRACT FROM AUTHOR]

A study was carried out to assess the regulation of compensatory growth under different restriction feeding regimes in Labeo rohita juveniles by the interaction of various feed intake and growth regulating genes. A 60 day feeding trial was conducted with five treatment groups, Control (3% body weight, bw), T1 (alternate days), T2 (0.5% bw), T3 (1% bw) and T4 (2% bw) and feeding was done for first 30 days of the trial. For next 30 days, all the treatment groups were fed at a rate of 3% bw as in the control group. There was significant (p < 0.05) difference in the weight gain among the treatment groups with lowest FCR and highest PER was found in T2 group. Ghrelin gene mRNA levels were upregulated during first 30th days of the trial with highest expression levels in the T2 group. The expression levels of leptin gene mRNA were found significantly different (p < 0.05) among the treatments, which was down-regulated during initial 30 days and upregulated as the experiment progress towards 60th day. The IGF-1 mRNA expression levels were upregulated more in liver compared to the muscle tissue. The results of the study suggest that increased ghrelin levels and decreased leptin levels lead to hyperphagia during the onset of refeeding, which further triggers the compensatory growth in L. rohit a. The present study describes the molecular mechanism behind the compensatory growth following a different feed restriction regime in L. rohita which is regulated due to the interaction of different energy homeostasis and growth regulating genes. [ABSTRACT FROM AUTHOR]

Mulberry (Morus L.) is an economically important tree being cultivated for its leaves to rear the silkworm Bombyx mori. Rearing of silkworm is an art and science popularly known as sericulture; an agrobased cottage industry provides employment to millions in China, India, Korea, Vietnam, etc. Mulberry is a perennial tree that maintains high heterozygosity due to the outbreeding reproductive system. It is recalcitrant to most of the conventional breeding methods, yet considerable improvement has been made in leaf yield and leaf quality. Conventional breeding in mulberry is a tedious, labour intensive and time taking process, which needs to be complemented with modern biotechnological methods to speed up the process. This article enumerates the problems, challenges, constraints and achievements in mulberry breeding along with recent advances in biotechnology and molecular biology to enable mulberry breeders to tackle specific problems more systematically and effectively. [ABSTRACT FROM AUTHOR]

The common carp ( Cyprinus carpio L.) is one of the major aquaculture species, contributing nearly 35% to the inland fish production in Karnataka, India. Stocks collected from Hungary (2), Indonesia and Vietnam were assessed alongside two local stocks in a series of culture performance trials with the objective of setting up a base population for developing a breeding programme. The present study deals with the genetic divergence and polymorphism in these six stocks using random-amplified polymorphic DNA (RAPD) markers. A total of 180 decamer random primers were screened for polymerase chain reaction (PCR) amplification (OPA 1-20, OPB1-20, OPC1-20, OPD1-20, OPE1-20, OPF1-20, OPG1-20, OPP1-20 and OPM1-20). Eight primers were selected for analysis of common carp genotypes (OPA-7, OPA-20, OPB-17, OPF-10, OP F-9, OPG-4, OPG-9 and OPP-16). Out of 492 bands recorded, 57.1% were polymorphic. Stepwise regression analysis was carried out to find best combination markers affecting body weight ( P<0.001). The results demonstrate major differences in the genetic structures between different stocks. Dendrogram data showed grouping of individuals according to stocks and corresponding data variables revealed the per cent homology within the stock and also found markers correlating to the body weight. [ABSTRACT FROM AUTHOR]

The present study aimed to understand titanium dioxide nanoparticle (TiO 2 -NPs) induced changes in selected hormones of hypothalamic-pituitary-thyroid/gonad axis in adult females of Labeo rohita , as well as the possible ameliorative role of dietary vitamin E and folic acid. Firstly, adult females of Labeo rohita were injected intraperitoneally with two sublethal doses (1/50 LD 50 ; 10.6 μg kg−1 and 1/10 LD 50 ; 52.8 μg kg−1) of TiO 2 -NPs and the effect in terms of gonadosomatic index, reproductive & thyroid hormones, vitellogenin, and cortisol were assessed after 21 days of exposure. Subsequently, TiO 2 -NPs pre-exposed fish were supplemented with vitamin E and folic acid in different combinations for 30 days. The control diet fulfilled the minimum requirement, while two higher doses of vitamin E (200 and 250 mg/kg diet) and folic acid (3 and 4 mg/kg diet) were used in experimental diets. The results showed significant alteration of gonadotropins (an increase of FSH and LH), thyroid hormones (an increase of T 3 and T 4 without substantial change in TSH), cortisol, steroid hormones, and vitellogenin, upon TiO 2 -NPs exposure. Among the steroid hormones, testosterone and progesterone levels declined significantly with a concomitant increase in estradiol. More precisely, exposure to 52.8 μg kg−1 TiO 2 -NPs increased serum estradiol and cortisol to the extent of 98% and 77%, respectively. While serum vitellogenin in Labeo rohita exposed to low and high doses of TiO 2 -NPs decreased by 29% and 58%, respectively, indicating the adverse effect of TiO 2 -NPs on reproduction. Dietary administration of vitamin E and folic acid reduced oxidative stress as characterized by lowered antioxidative enzyme's activities. Further, most of the harmful effects of TiO 2 -NPs were ameliorated by dietary fortification of vitamin E and folic acid, with vitamin E having more pronounced effect. • We studied the effect of titanium nanoparticles (TiO 2 -NPs) on Labeo rohita females. • TiO 2 -NPs affected gonadotropins, sex steroids, vitellogenin and thyroid hormones. • Dietary vitamin E and folic acid found to ameliorate reprotoxicity in Labeo rohita. • Dietary vit. E and folic acid found to reduce TiO 2 -NPs mediated oxidative stress. [ABSTRACT FROM AUTHOR]

Carotenoprotein, a complex of carotenoids and protein, extracted from shrimp shell waste can be an effective source of carotenoid as well as antioxidant in fish diets. In the present study, the nutritional potential of carotenoprotein extracted from shell wastes of Parapeneopsis stylifera on growth, physiometabolic changes and coloration in high-value ornamental fish, oscar (Astronotus ocellatus) was assessed in a 120 days feeding trial. Four iso‑nitrogenous (30–31% CP) and isolipidic (11.34–11.55% CL) diets were formulated with graded levels of carotenoprotein inclusion like 0%, 5%, 10% and 15% and designated as Control, T1, T2 and T3 respectively. At the end of the feeding trial, growth indices such as final body weight, weight gain, and specific growth rate indicated that fish fed with 10 and 15% levels of carotenoprotein incorporated diet showed higher growth compared to control and T1. Oxidative stress enzymes like SOD and Catalase were lower in 15% and 10% carotenoprotein incorporated diets respectively in both gills and liver. Stress indicators like serum glucose and cortisol activity were found to be higher in control than in diets with 10% (T2) as well as 15% (T3), suggesting the stress-reducing ability of the carotenoprotein in fish feed. Relatively higher respiratory burst activity in fishes of T3 group indicated higher immunity status of the fish. Quantitative colour values in terms of redness, chroma in the fin region as well as carotenoid content in scale, skin and muscle of fish were higher in T2 (10% carotenoprotein incorporated diet) as compared to T3 (15% carotenoprotein incorporated diet). Overall, this study clearly showed that dietary incorporation of as little as 10% carotenoprotein is advisable to ornamental fish farmers for enhanced growth, colouration, as well as antioxidant activity in this popular high value ornamental fish for maximizing their profit. • Dietary supplementation of shrimp carotenoprotein on ornamental fish was studied. • Improved growth, better feed utilization and antioxidant activity observed. • Higher level of carotenoprotein up to 10% significantly improved the immune status. • Instrumental L*, a*, b* values, chroma, hue angle was superior in 10% inclusion level. • Inclusion of carotenoprotein is cost effective as evaluated by BCR against their costs. [ABSTRACT FROM AUTHOR]

Utilizing agro-industrial waste and herbal products to create a circular bioeconomy is becoming increasingly popular. Terminalia arjuna is a significant ethnomedicinal plant that has not yet been exploited in animal feed. In the present study, nutritional Terminalia arjuna bark powder-based fish feed was created and supplied to a candidate fish species Labeo rohita at varied levels: 0% (0 g/kg), 0.5% (5 g/kg), 1% (10 g/kg), and 1.5% (15 g/kg). These treatment groups are denoted as CT, T1, T2, and T3, respectively. Utilizing a contemporary comprehensive biomarker response strategy, the study clarified the genomic influence of dietary herb inclusion. In response to bacterial infection, the immunogenic genes, STAT 1 (signal transducer and activator of transcription 1), ISG 15 (interferon stimulating gene), and Mx "myxovirus resistance gene", were shown to be elevated. The results of densitometry demonstrated a dose-dependent increase in STAT 1 and ISG 15, with Mx exhibiting maximal values at 1 g/kg TABP ( Terminalia arjuna bark powder-based feed). This is the first study to identify TABP as an immunomodulator in fish and established the IBR (Integrated Bio-marker Response) as a reliable marker in evaluating the impact of multiple drivers in a holistic manner. Thus, the present study cleared the path for TABP to be utilized as an effective feed additive which enhances the specific adaptive immune system of the fish for the production of the Green fish product for a sustainable circular bioeconomy.

This study assessed the responses of vitamin-D 3 intraperitoneally injected to Rohu, Labeo rohita @ of 0 IU/kg bw (only solvent), 100 IU/kg bw and 500 IU/kg bw reared in 20 and 40 ppm of calcium (Ca) enriched water. The cellular changes in Corpuscles of Stannius (CS) gland, serum Ca, and inorganic phosphate (P i ) level were analysed up to the 60th day. Rohu administered with 100 IU/kg bw D 3 and exposed to 40 ppm Ca-rich water exhibited notable hyperplasia of CS compared with their control groups. Notable changes with high serum Ca level (13.87 ± 0.3 mg/dl) was detected on the 5th day in fish exposed to 40 ppm Ca-rich water, while related values attained (13.74 ± 0.1 mg/dl) only after 7 days in 20 ppm Ca-rich water of 500 IU/kg bw vitamin D 3 injection. Similarly, high serum P i level (7.66 ± 0.2 mg/dl) in 40 ppm Ca injected with D 3 at 500 IU/kg bw. The results demonstrated that the Ca homeostasis of Labeo rohita is influenced by intra-peritoneal vitamin D 3 . Progressive studies should be conducted by increasing the dose of vitamin D 3 to investigate optimum dose/supplement in feed for commercially important aquaculture teleost Labeo rohita for maximum and sustainable absorption of Ca from the variable water Calcium levels to maintain Ca 2+ homeostasis., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2020 The Authors.)