Inland Saline Water Research Articles

Inland saline culture of GIFT (Oreochromis niloticus) juveniles: effect of graded levels of lipid on growth and haemato-biochemical responses.

60-days trial was performed to study the effect of inland saline water (ISW) at 10ppt salinity on lipid requirement of Genetically Improved Farmed Tilapia (GIFT) juveniles. Six purified iso-nitrogenous (37% crude protein) and hetero-caloric (380-430 Kcal DE/100g) diets having graded levels of dietary lipid viz., 4, 6, 8, 10, 12 and 14% were prepared. Two hundred and seventy acclimated GIFT juveniles (1.90 ± 0.1g) were randomly distributed (15 fish per 300L tank) into six different treatments viz., T4, T6, T8, T10, T12 and T14 in triplicates. The increase in dietary lipid resulted in an increase in body lipid and a diminution in moisture levels in fish. There was a significant (p < 0.05) increase in weight gain (g), percent weight gain (WG%), protein efficiency ratio (PER) and feed efficiency ratio (FER) with increasing dietary lipid level up to 8% and decreased thereafter, but an opposite trend was noted in the feed conversion ratio (FCR). The serum glucose level linearly elevated with the rise in dietary lipid level, but higher lipid (beyond 8%) fed groups showed significantly (p < 0.05) more total protein in serum. Though there was a significant (p < 0.05) difference in cholesterol levels, no clear trend was observed; while other parameters viz., body indices (VSI and HSI), serum albumin, globulin and A-G ratio was not showed any significant (p > 0.05) variation with varying dietary lipid level. Based on regression models, it was observed that the optimum lipid level required for GIFT in ISW (10ppt) is in the range of 8.35-9.05%.

Growth and biochemical composition of green seaweed Chaetomorpha linum (O.F. Müller) Kützing (1845) cultured in a range of ionic profiles

Seaweed aquaculture in Inland Saline Water (ISW) can utilise degraded land to produce valuable products. ISW is characterized by its different ionic profile to ocean water (OW), particularly the ratios of sodium (Na+) to potassium (K+) ions, and magnesium (Mg2+) to calcium (Ca2+) ions. The feasibility of seaweed cultivation in varying ionic profiles is not yet well understood. This study investigates the growth of Chaetomorpha linum by length (SL) and biomass (TB), cultured in several ionic profiles by mixture of ISW with OW over two 15-day experiments. The first experiment (EXP 1) investigated growth across a broad range of ionic profiles. C. linum was then cultivated across a more specific range of profiles in the second experiment (EXP 2), based on EXP 1 results. Tanks (50 L) were randomly organised outdoors and salinity was maintained at approximately 25 ppt. SL and TB of seaweed was recorded every 3 days. The proximate and mineral composition of harvested seaweed on Day 15 was also analysed. A significant negative correlation (p < 0.001, r = −0.835, N = 13) was observed between non-discrete TB specific growth rate (SGR) and increasing K+ of media in EXP 1. A significant positive correlation (p < 0.001, r = 0.769, N = 28, EXP 1) was observed between potassium (K) in dry matter (mg.g−1) and K+ in media, suggesting lower K+ in media causes increased TB due to higher water flow rate into cells. Calcium (Ca) content (%d.b.) was much higher in K+ deficient media, indicating Ca accumulation occurs in cells to for ion homeostasis when K is not available. Positive SL SGRs across ionic profiles also indicate this species is capable of a high level of internal ion homeostasis. This study provides context for commercial cultivation of C. linum in varying water types, and presents an avenue for salinity-affected dryland farmers to diversify their income through ISW aquaculture.

Optimization of dietary protein based on ideal protein concept for genetically improved farmed tilapia (GIFT) juveniles reared in inland saline water

A 60-day feeding trial was performed to optimize dietary protein based on the ideal protein concept for genetically improved farmed tilapia (GIFT) juveniles reared in inland saline water (ISW) of 10 ppt salinity. Seven heteronitrogenous (373.6–256.5 g crude protein/kg), isocaloric (∼ 16 MJ digestible energy/kg) and isolipidic (∼ 80 g lipid/kg) semi-purified feeds were formulated and prepared with decreasing levels of crude protein (CP), namely 373.6 (CP1), 352.2 (CP2), 334.5 (CP3), 314.9 (CP4), 293.7 (CP5), 275.2 (CP6) and 256.5 g/kg (CP7). The proportion of total essential and semi-essential amino acids was kept constant in all diets as ideal amino acid profiles and total non-essential amino acids were reduced linearly to reduce the dietary CP levels. Three hundred fifteen juveniles (average weight 4.76 ± 0.01 g) were randomly assigned into seven groups in triplicate. Fish of various groups were fed thrice daily at an apparent satiation level. The growth of juveniles increased linearly and quadratically (p<0.05) when the CP level of diets was decreased from 373.6 (CP1) to 334.5 g/kg (CP3), then declined linearly. The CP2 and CP3 groups had significantly higher feed intake and lower feed conversion ratio. In contrast, low CP-fed groups had superior protein utilization, viscerosomatic index and hepatosomatic index than other groups. The CP1 and CP2 groups had significantly higher whole-body protein and lower lipid content. The whole-body non-essential amino acid content diminished linearly (p<0.05) as dietary CP levels were decreased; the whole-body essential amino acid content remained unchanged (p>0.05). The high CP-fed juveniles (CP1 and CP2) showed a significantly (p<0.05) elevated protease activity, whereas the opposite trend was noticed for amylase activity. The aminotransferase activities of the liver and muscle were reduced linearly (p<0.05) with reduced dietary CP levels. Serum glucose and cholesterol contents elevated linearly (p<0.05) with decreased dietary CP levels. Whereas, the hemoglobin content and RBC count decreased (p<0.05) in the high CP-fed juveniles. The second-order polynomial regression analysis revealed that the optimal dietary CP levels could range from 311.1 to 318.0 g/kg for GIFT juveniles reared in ISW of 10 ppt salinity. Furthermore, by adopting the ideal protein concept, the CP levels in the diet of GIFT juveniles could be reduced from 373.6 to 311.1 g/kg without affecting growth performance. The outcome of this study will assist in developing a low-protein feed with balanced essential amino acids for GIFT culture in ISW.

Optimal level of dietary arginine enhances growth performance, haemato-biochemical status, metabolic responses and growth-related gene expression of GIFT juveniles reared in inland saline water

The effects of arginine levels in diets on growth performance, survival, and haemato-biochemical responses and gene expression of genetically improved farmed tilapia (GIFT) juveniles raised in inland saline water (ISW) of 10 ppt were evaluated through a 60-day growth trial. Seven isoproteinaceous (⁓320 g protein/kg), isolipidic (80 g/kg) and isoenergetic (16.8 MJ DE/kg) diets with graded levels of arginine viz. A10 (10 g/kg), A12.5 (12.5 g/kg), A15 (15.0 g/kg), A17.5 (17.5 g/kg), A20 (20.0 g/kg), A22.5 (22.5 g/kg) and A25 (25.0 g/kg) were prepared. Acclimated GIFT juveniles (3.75 ± 0.017 g) were randomly assigned into seven treatments in triplicate with 15 fish/replicate and fed with respective diets thrice a day on a satiation basis. The percent weight gain, specific growth rate, protein efficiency ratio, whole carcass protein, tissue alanine and aspartic acid aminotransferase activities, serum total protein, albumin and globulin concentration and expression of IGF-1 & IGF-1R genes of fish significantly increased, while feed conversion ratio significantly decreased with increasing arginine in the diet up to 17.5 g/kg and decreased thereafter. Additionally, white blood cell count increased with rising arginine levels in the diet. However, body indices, survival, whole carcass lipid, total ash and essential amino acids contents, activities of digestive and antioxidant enzymes, serum glucose level and blood haemoglobin level and red blood cell count of fish remained unchanged for different treatments. Based on broken-line regression and second order polynomial regression models in relation to hepatic IGF-1 gene expression and percent weight gain, the dietary optimal arginine level was found to be 15.97 and 16.76 g/kg and 17.06 and 17.41 g/kg, respectively with the optimum range of 15.97 to 17.41 g/kg for successful culture of GIFT in ISW of 10 ppt salinity.

Phytoremediation Potential of Macrophytes from Calcium Fortified Ground Water under Laboratory Condition to Improve Water Quality

To select the best macrophyte for the phytoremediation of calcium from Ca-fortified ground water and inland saline water, 1 week screening was done for Eichhornia crassipes, Salvinia molesta and Lemna minor by using four effective concentrations of Calcium viz., 200, 400, 600 and 800 mg L–1. Experiment was done in triplicate. Water samples were collected at one day interval and plant samples at the end of experiment. The Calcium uptake concentration was found significantly (p&lt;0.05) higher for E. crassipes on 6th day (5.37%) of experiment at effective concentration 800 mg L–¹, followed by S. molesta (4.87%) and L. minor (4.13%). Further experiment was conducted for 1 month for water quality analysis and testing the Calcium uptake, and found that there was significant improvement in water quality parameters. The finding of this study will serve baseline information for treatment of inland saline water to make it useful for various agricultural and aquaculture applications.

Effect of sulfate on the osmoregulatory and physio-biochemical responses of GIFT (Oreochromis niloticus) juveniles reared in potassium-deficient medium saline waters.

The inland saline waters were continuously observed to have low potassium concentrations compared to their seawater counterpart of the same salinity. We hypothesize that the toxic effect of sulfate may manifest in low potassium saline (LPSW) waters compared to brackish water of the same salinity. Thus, LC50 trials were performed in GIFT (genetically improved farmed tilapia) fry (0.5 ± 0.02 g) to determine the acute sulfate toxicity in freshwater (FW, 0.5 g L-1), artificial seawater (ASW, 10 g L-1), and LPSW (10 g L-1). The median lethal concentrations (96h LC50) of sulfate ion in FW, LPSW, and ASW for the GIFT were 5.30 g L-1, 2.56 g L-1, and 2.98 g L-1, respectively. A second experiment was conducted for 21 days, exposing fish to a sub-lethal level of sulfate ion (SO42-) concentration (1000 mg L-1, one-fifth of FW LC50) with different types of waters (FW, freshwater, 0.5 g L-1; ASW, artificial seawater, 10 g L-1; LPSW, low potassium saline water, 10 g L-1) with and without sulfate inclusion to constitute the treatments as follows, (FW, FW + SO4, ASW, ASW + SO4, LPSW, LPSW + SO4). The effect of sulfate on GIFT reared in sulfate-rich potassium-deficient medium saline water was evaluated by focusing on the hematological adjustments, stress-induced oxidative damage, and osmoregulatory imbalances. The survival was not altered due to the sulfate concentration and K+ deficiency; however, there were significant changes in branchial NKA (Na+/K+-ATPase) activity and osmolality. The increase in NKA was highest in LPSW treatment, suggesting that internal ionic imbalance was triggered due to an interactive effect of sulfate and K+ deficiency. The cortisol levels showed a pronounced increase due to sulfate inclusion irrespective of K+ deficiency. The antioxidant enzymes, i.e., SOD (superoxide dismutase), catalase, GST (glutathione-S-transferase), and GPX (glutathione peroxidase), reflected a similar pattern of increment in the gills and liver of the LPSW + SO4 groups, suggesting a poor antioxidant status of the exposed group. The hepatic peroxidation status, i.e. TBARS (thiobarbituric acid reactive substances), and the peroxide values were enhanced due to both K+ deficiency and sulfate inclusion, suggesting a possible lipid peroxidation in the liver due to handling the excess sulfate anion concentration. The hematological parameters, including haemoglobin, total erythrocyte count, and hematocrit level, reduced significantly in the LPSW + SO4 group, indicating a reduced blood oxygen capacity due to the sulfate exposure and water potassium deficiency. The hepatic acetylcholine esterase activity was suppressed in all the treatments with sulfate inclusion, while the highest suppression was observed in the LPSW + SO4 group. Thus, it is concluded that sulfate-induced physiological imbalances manifest more in potassium-deficient water, indicating that environmental sulfate is more detrimental to inland saline water than freshwater or brackish water of the same salinity.

Mineral supplementation in biofloc influences growth and haemato-biochemical indices of Genetically Improved Farmed Tilapia reared in inland saline ground water

An experiment for a period of 60 days was performed with species specific mineral supplementation in biofloc system for GIFT tilapia reared in inland saline water. Four different concentrations of formulated mineral mixture (10, 15, 20, 25 g L−1) were supplemented in the subculture of biofloc inoculum for different treatments (T1, T2, T3, and T4). In contrast, two control groups (conventional culture system (C) and a standard biofloc control (BC) devoid of mineral supplements) were maintained. Major water quality parameters were optimal except alkalinity and pH, which were fluctuated in the treatment groups, and higher turbidity was noticed only in the T4 group. The minerals supplemented groups had lower levels of TAN, nitrite (NO2) and nitrate (NO3) than conventional biofloc system (BC). Floc parameters such as floc volume, total suspended solids (TSS), total dissolved solids (TDS) and total solids (TS) were higher than the control. Haematological parameters Hb (haemoglobin) and WBC (white blood corpuscles) of fish reared in treatments were higher, ranging from (8.2 ± 0.64 −10.47 ± 0.66 g dL−1) and (187.83–215.17 ± 6.58 per cumm) respectively (P < 0.05) compared to both the controls. Serum parameters of fish was recorded to be higher in T2. The proximate composition analysis revealed an enhanced crude protein content (33.22 ± 1.00%, 67.68 ± 0.2%) and crude lipid (5.24 ± 0.22% & 15.18 ± 0.58%) (P > 0.05) content from BC, but ash content (39.11 ± 0.1% & 20.35 ± 0.21%) from T4 in both dried biofloc and fish samples were higher than rest of the groups. Specific growth rate (SGR) and weight gain (WG) were recorded to be significantly higher in the T2 group. Feed conversion ratio (FCR) was observed to be better in all the treatments and the BC group than conventional control. The current investigation showed that subculture of biofloc inoculum supplemented with formulated mineral mix of 15 g L−1 could be effective in terms of water quality maintenance, feed utilization, growth, survival and biochemical parameters of GIFT tilapia reared in inland saline ground water.

Sugarcane bagasse biochar enhances the growth parameters, haematological parameters, and enzyme activities of genetically improved farmed tilapia (GIFT) reared in inland saline water.

In the present scenario, waste management, especially agro-waste, is one of the major challenges. India is an agrarian country and the economy depends on agriculture and a huge amount of agro-wastes are generated. In this study, biochar was prepared from paddy straw and sugarcane bagasse and was used in the feed of genetically improved farm tilapia (GIFT) at 0.5% (w/w) basis to study its effect on growth and haematological parameters. An experiment was carried out in triplicate in 500-l capacity FRP tanks comprising two treatments and one control. Tanks were filled with inland saline soil to maintain 25-cm soil's bed and water with 12 ppt salinity. A total of 22 fish having an average length of 5.14 ± 0.07cm and weight of 4.8 ± 0.05g were stocked in each tank; the fish were fed at apparent satiation level, twice daily for 45days. It was observed that growth parameters like SGR% (specific growth rate), weight gain (WG%), and feed conversion ratio (FCR) were significantly improved (p < 0.05) than the control. Biochar-enriched feed also significantly improved the haematological parameters like red blood cell (RBC), white blood cell (WBC), haemoglobin (Hb) haematocrit % (HCT), mean cell haemoglobin concentration (MCH), and MCV (mean cell volume) in treatment groups than the control. Feeding biochar as feed additives was also found to decrease catalase (CAT) and enhanced amylase and lipase activities in treatments as compared to control (p < 0.05). It can be concluded that the application of biochar as a feed additive enhanced the growth and overall health of the fish, and it can enhance fish production. However, biochar from sugarcane bagasse was found to be more effective than the paddy straw biochar in the diet of tilapia (GIFT).

Glycerol monolaurate improves growth, lipid utilization and antioxidative status of white-leg shrimp, Penaeus vannamei fed with varying protein-lipid diets reared in inland saline water

Higher lipid at suboptimum dietary protein level can be a suitable approach to formulate cost-effective feed for cultured fish. However, excess lipid may cause metabolic burden to animals resulted in growth retardation with lipid deposition. Therefore, a feeding trial of 60 days was conducted to assess the effect of glycerol monolaurate (GML) supplemented in varying protein and lipid diets on growth, lipid utilization, antioxidant status and biochemical indices of white-leg shrimp, Penaeus vannamei juveniles reared in inland saline water (ISW). Accordingly, three hetero-lipidic (5–9% lipid), hetero-nitrogenous (30–36% CP), and hetero-energetic (379–400 Kcal DE/100 g) diets with three levels of GML (0%, 0.07% and 0.1%) were formulated for nine diets viz. P36L5G0 (36% CP, 5% lipid and 0% GML), P36L5G0.07 (36% CP, 5% lipid and 0.07% GML), P36L5G0.1 (36% CP, 5% lipid and 0.1% GML), P33L7G0 (33% CP, 7% lipid and 0% GML), P33L7G0.07 (33% CP, 7% lipid and 0.07% GML), P33L7G0.1 (33% CP, 7% lipid and 0.1% GML), P30L9G0 (30% CP, 9% lipid and 0% GML), P30L9G0.07 (30% CP, 9% lipid and 0.07% GML) and P30L9G0.1 (30% CP, 9% lipid and 0.1% GML). Five hundred and forty P. vannamei juveniles (4.02 ± 0.01 g) were randomly distributed following 3 × 3 factorial design. Highest (p < 0.05) weight gain. Specific growth rate, protein efficiency ratio, lipid efficiency ratio, whole body protein with lowest feed conversion ratio, whole body lipid, and hepatopancreas–somatic index was recorded in P33L7G0.1 group. Hepatopancreatic amylase and lipase activities increased (p < 0.05) significantly while protease activity decreased in relation to increased levels of dietary lipid. However, supplementing GML resulted in increased (p < 0.05) activity of all digestive enzymes and highest activity was found in 0.1% GML fed group. Lipid metabolic enzyme glucose-6-phosphate dehydrogenase and carnitine palmitoyltransferase-1 activities were found maximum (p < 0.05) in P33L7G0.1 group and lowest in P36L5G0 group. Hepatopancreatic and branchial superoxide dismutase and catalase activities showed a decreased (p < 0.05) and increased trend with dietary lipid levels, while GML reduced the activities and lowest activity recorded in P33L7G0.1 group. Shrimps of 9% lipid group exhibited highest serum malondialdehyde, glucose, cholesterol and triglyceride levels but 0.1% GML significantly showed the lowest levels that other groups. Higher hemocyanin and total protein observed in 33% dietary protein and 0.1% GML fed group. Therefore, 33% protein, 7% lipid with 0.1% GML is optimum for maximum growth performance, lipid utilization, whole body protein, and antioxidative status of white-leg shrimp, P. vannamei juveniles reared in ISW of 10 ppt.

Histopathological Alterations in Major Organs of Freshwater Ornamental Goldfish, (L.), Variety Shubunkin Carassius auratus Reared in Inland Saline Water

Histopathological Alterations in Major Organs of Freshwater Ornamental Goldfish, (L.), Variety Shubunkin Carassius auratus Reared in Inland Saline Water

Salinity tolerance response of ornamental black molly, Poecilia sphenops exposed to inland saline water

Salinity tolerance response of ornamental black molly, Poecilia sphenops exposed to inland saline water

Salinity induced changes in growth and gill structure of freshwater carp, Cyprinus carpio Linn.

Aim: The present study was carried out to evaluate salinity induced changes in the growth and gill structure of cosmopolitan freshwater carp, Cyprinus carpio (Linn.). Methodology: Inland saline water (15 ‰ or g l-1) was collected from the salt affected waterlogged areas of village Shajrana (30.3346 0N, 74.1196 0E) in District Fazilka, Punjab (India) and diluted with underground freshwater for preparing different salinity levels (2 to 10 ‰). Fingerlings (10 ±2 cm) of C. carpio were exposed to 0 (control), 2, 4, 6, 8 and 10 ‰ salinity after gradual acclimatization with salinity increase @ 1 ‰ hr-1. Results: At the end of 120 days of rearing under saline conditions, 100% fish survival was observed up to 6 ‰ salinity, while 86.66 and 70.00% survival was recorded in 8 and 10 ‰, respectively. However, fish growth declined significantly at all salinity levels (p≤0.05). Gill structure was also affected at all salinity level, but pronounced changes were observed at salinity levels ≥ 6 ‰, including lamellar oedema, epithelial lifting, lamellar hyperplasia, hypertrophy, lamellar fusion, hyalinisation, aneurysm, blood congestion, etc. Interpretation: The results offer referral database to explore optimised economic production of common carp in inland saline areas of the region at salinity levels below 6 ‰. Key words: Carp, Gills, Growth, Production, Salinity, Survival

Effect of salinity on serum steroid levels and gonad development in common carp (Cyprinus carpio Linnaeus, 1758) reared in inland saline water

The effect of salinity on serum steroid levels and gonadal development were investigated in the common carp Cyprinus carpio Linnaeus, 1758. Fishes were stocked in eight rectangular earthen ponds at four different salinities of 0, 5, 10 and 15 ppt. Changes in serum concentration of cortisol, 17 β – Estradiol, progesterone; 17α, 20β dihydroxyprogesterone and androgens were investigated. Gonadal histology in male and female C. carpio was studied at different stages of gonadal maturity till ovulation or spermiation. Serum steroid analysis showed significantly high levels (p&lt;0.05) in fish groups reared at 0 and 5 ppt compared to 10 and 15 ppt. Significantly higher cortisol levels were found during ovulation or spermiation at 10 and 15ppt. In the present study, C. carpio was found to mature faster at 5 ppt as compared to higher salinities of 10 and 15 ppt, in inland saline water. Keywords: Aquaculture, Cyprinus carpio, Maturation, Salinity, Steroid hormones

Dietary magnesium chelate alleviates oxidative stress and improves growth in white-leg shrimp, Penaeus vannamei (Boone, 1931), reared in inland saline water

Nine semi-purified diets containing either magnesium citrate (MgC) levels of 0.0, 2.24, 4.48, 6.72, 8.96 g Kg-1 or magnesium amino acid complex (MgAA) levels of 2.17, 4.35, 6.52, 8.7 g Kg-1 were fed to P. vannamei juveniles thrice daily and reared for 60 days in sub-optimum inland saline ground water (ISGW) of 10‰. Five hundred sixty-seven healthy juvenile shrimps (3.51 ± 0.03 g) were randomly stocked in triplicate into 350 L tanks at a density of 60 m-3. The weight gain (WG %) and specific growth rate were highest in the shrimps fed with 4.48 g Kg-1 MgC and 2.17 g Kg-1 MgAA. Further increase in the dietary magnesium did not show any additional growth, relatively inhibited it. The positive correlations (p < 0.01) between WG % and magnesium contents of serum, body and hepatopancreas suggests indirect involvement of tissue magnesium in growth performance. Conversely, negative correlations (p < 0.01) of WG % with superoxide dismutase and heat shock protein 70 (HSP 70) in gill and hepatopancreas indicate stress-induced inhibition of growth. Higher inclusion of dietary magnesium altered sodium-potassium ATPase (NKA) mRNA expression in hepatopancreas. The minimum dietary MgC and MgAA supplementations of P. vannamei juveniles for growth improvement were determined to be 4.25 g Kg-1 and 2.38 g Kg-1 feed, respectively, which was equivalent to 2.86 g Kg-1 and 1.64 g Kg-1 feed respectively, using broken-line regression analysis based on the weight gain (%). Overall results reveal that dietary MgAA was better than MgC in alleviating ionic stress and improving growth performance and survival rate in shrimp reared in 10‰ ISGW of the sub-optimum magnesium suite.

Bile acid improves growth, lipid utilization and antioxidative status of genetically improved farmed tilapia (Oreochromis niloticus) fed with varying protein-lipid diets reared in inland saline water

A 60-day feeding trial was conducted to find out the effect of bile acid supplemented diets with varying protein and lipid levels on growth performance, body composition, antioxidant status and physio-biochemical responses of genetically improved farmed tilapia (GIFT) juveniles reared in inland saline water (ISW) of 10 ppt. Three hetero-nitrogenous (38–32% crude protein, CP), hetero-lipidic (8–14% lipid) and hetero-caloric (409–439 Kcal digestible energy/100 g) diets were supplemented with three levels (0%, 0.05% and 0.1%) of bile acid to prepare nine experimental diets viz. P38L8B0 (38% CP, 8% lipid and 0% bile acid), P38L8B0.05 (38% CP, 8% lipid and 0.05% bile acid), P38L8B0.1 (38% CP, 8% lipid and 0.1% bile acid), P35L11B0 (35% CP, 11% lipid and 0% bile acid), P35L11B0.05 (35% CP, 11% lipid and 0.05% bile acid), P35L11B0.1 (35% CP, 11% lipid and 0.1% bile acid), P32L14B0 (32% CP, 14% lipid and 0% bile acid), P32L14B0.05 (32% CP, 14% lipid and 0.05% bile acid) and P32L14B0.1 (32% CP, 14% lipid and 0.1% bile acid). Four hundred and five acclimated GIFT juveniles (2.51 ± 0.01 g) were randomly distributed in nine treatment groups in triplicate (stocking density 15 fish/tank, 300 L) following 3 × 3 factorial design. Results indicated that body lipid, feed conversation ratio (FCR), amylase and lipase activities, gill and liver superoxide dismutase (SOD) and catalase (CAT) activities and serum glucose (GLU), total protein, triacylglycerol (TAG), total cholesterol (T-CHO), and low density lipoprotein cholesterol (LDL-CHO) were significantly (p < 0.05) increased and weight gain percentage (WG%), specific growth rate (SGR), protease activity and high density lipoprotein cholesterol (HDL-CHO) were significantly (p < 0.05) decreased with increasing dietary lipid levels and more pronounced effect was found in fish fed 32% protein and 14% lipid. Dietary bile acid significantly (p < 0.05) increased WG%, SGR, protein efficiency ratio, lipase activity and HDL-CHO and significantly (p < 0.05) decreased FCR, gill and liver SOD and CAT activities and serum GLU, TAG, T-CHO, and LDL-CHO with more pronounced effect by 0.05% dietary bile acid. In conclusion, feeding of 35% crude protein, 11% lipid and 0.05% bile acid can cause better growth performance, antioxidant status and physio-biochemical responses of GIFT juveniles reared in ISW of 10 ppt. This information will be useful in formulating the bile acid supplemented eco-friendly low protein high lipid (LPHL) feed for profitable culture of GIFT in ISW.

Effect of Pulsed Feeding of GIFT Strain of Tilapia in Biofloc System Using Inland Saline Water

Feed is one of the major inputs in aquaculture system and constitutes 60%–80% of total production costs of tilapia. Inappropriate selection of feed quality and the feeding strategy affects the feed utilization resulting in high food conversion ratio (FCR). A 60 days experiment was conducted to evaluate the growth performance and immuno-physiological responses of GIFT tilapia, (Oreochromis niloticus) by pulsed feeding under biofloc culture system in inland saline water. For the experiment, feeding pattern in pulsed was followed viz., in situ biofloc with daily feeding (T1), in situ biofloc with alternate day feeding (T2), in situ biofloc with every third day feeding (T3), in situ biofloc with no feeding (T4), and clear water control with daily feeding (C) each in triplicates. Biofloc based treatment receiving daily feeding (T1) resulted in significantly (P&lt;0.05) higher average body weight, weight gain, and specific growth rate (SGR) compared to control. T1 and C showed a significantly similar feed conversion ratio (FCR) and protein efficiency ratio (PER). Fish maintained in T4 grew the least and survival was lowest (85%). The immunological parameters showed a significant difference (P&lt;0.05) for nitroblue tetrazolium (NBT) and myeloperoxidase content whereas no significant difference (P&gt;0.05) for lysozyme activity was observed. Higher NBT activity was observed in biofloc based treatments compared to control. Activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activity were considerably higher (P&lt;0.05) in biofloc based treatments than control. Among biofloc based treatments the antioxidant activities were lower in T1. The carbohydrate metabolism enzymes lactate dehydrogenase (LDH) and malate dehydrogenase (MDH) were lower in T1, T2, and T3 compared to control and T4. In conclusion, in-situ biofloc with daily feeding is found to be effective in growth improvement and to elicit immune-physiological responses in GIFT tilapia under pulsed feeding using biofloc based system.

Stocking for sustainable aqua-venture: optimal growth, yield and economic analysis of Penaeus vannamei culture in inland saline water (ISW) of India

Stocking for sustainable aqua-venture: optimal growth, yield and economic analysis of Penaeus vannamei culture in inland saline water (ISW) of India

Sugarcane bagasse biochar-amended sediment improves growth, survival, and physiological profiles of white-leg shrimp, Litopenaeus vannamei (Boone, 1931) reared in inland saline water

Sugarcane bagasse biochar-amended sediment improves growth, survival, and physiological profiles of white-leg shrimp, Litopenaeus vannamei (Boone, 1931) reared in inland saline water

Effect of graded levels of dietary methionine on growth performance, carcass composition and physio-metabolic responses of genetically improved farmed tilapia (GIFT) juveniles reared in inland saline water of 10 ppt

The current study aimed to optimize dietary methionine level for improving growth performance, carcass composition and physio-metabolic responses of genetically improved farmed tilapia (GIFT) juveniles reared in inland saline water of 10 ppt. Seven isonitrogenous (∿370 g crude protein/kg), isolipidic (∿80 g lipid/kg) and isocaloric (∿19 MJ gross energy/kg) purified diets were made with graded levels of methionine viz., 4.9 (M4.9), 7.2 (M7.2), 9.9 (M9.9), 12.3 (M12.3), 15.1 (M15.1), 17.4 (M17.4) and 19.8 g/kg (M19.8) with a constant level of cystine (3.2 g/kg). Completely randomized designs were followed to constitute seven distinct experimental groups and each group comprised of three experimental units. Fifteen juveniles (3.16 ± 0.01 g) were randomly stocked in each experimental unit. During the 60-day feeding trial, juveniles were fed with their respective experimental diets thrice daily at an apparent satiation level. The results revealed that growth (weight gain percentage, thermal growth coefficient and specific growth rate) and feed and nutrient utilization (feed conversion ratio, protein efficiency ratio and apparent net protein retention) were improved significantly with an increment in dietary methionine levels up to 12.3 g/kg, and methionine supplementation beyond that did not give extra benefit in relation to growth performance. Dietary methionine supplementation at various levels had no effect (P > 0.05) on the body indices, survival, carcass moisture and ash content and carcass essential amino acid composition of GIFT juveniles. The carcass protein level increased with an increment in dietary methionine levels up to 12.3 g/kg and then declined with further increment of dietary methionine level. However, carcass lipid content displayed the inverse trend of carcass protein content. GIFT juveniles fed a diet containing 12.3 and 15.1 g methionine/kg displayed elevated activities of liver and muscle aminotransferases activities, while the activity of digestive enzymes was unchanged among dietary groups. An increment of methionine up to 12.3 g/kg of diet resulted in a significant rise in serum protein and globulin concentration. Based on broken-line linear and second-order polynomial regression analysis in relation to weight gain percentage and feed conversion ratio, the optimum methionine requirements for GIFT juveniles reared in inland saline water of 10 ppt ranged from 12.1 to 14.1 g/kg of diet (32.7–38.1 g/kg of dietary protein) with supplementation of cystine at 3.2 g/kg.

The effects of non-lethal heat-shock-induced cross-protection on survival and growth of Pacific whiteleg shrimp, Litopenaeus vannamei in response to ionic stress in inland saline waters

Non-lethal heat shock (NLHS) was used to enhance tolerance to other stressors in aquatic organisms and its effects are associated with the accumulation of Hsp 70. A study was conducted to determine the effect of NLHS on the cross-protection of L. vannamei against stress in K+-deficient inland saline water. To determine the NLHS based on mortality and gill heat shock protein 70 (Hsp70) abundance, L. vannamei juveniles (3.52 ± 0.23 g) were reared in inland water of 10 ppt salinity with 100% seawater equivalent (SWequ) K+ fortification. As one hour of heat shock at 36 °C resulted no mortality and a 3.5-fold increase in Hsp70 protein in gills when followed by 8 h recovery at 28 °C, the 36 °C was designated as NLHS. Subsequently, P. vannamei juveniles (4.64 ± 0.01 g) were exposed to 1 h NLHS in inland saline water containing 25%, 50% and 75% of SWequ K+ in triplicates following a recovery of 8 h, whereas the control group did not receive NLHS. The NLHS significantly increased Hsp70 protein in the gills and muscle. In addition, NHLS brought about higher catalase and superoxide dismutase activity in the gills and hepatopancreas, along with increased serum glucose levels. Increased Hsp70 protein abundance in muscle and gills remained elevated even after 12 h exposure to varying K+ levels, conferring cross-protection by NLHS against ionic stress caused by K+ depletion in inland saline waters. A 45-day growth study showed a significant increase in weight gain and survival (%) in NLHS groups compared to the control group, irrespective of the K+ fortification. This growth-promoting effect of NLHS was also evident in the group reared in the most K+ deficient inland saline water. This study shows that NLHS provides cross-protection through accumulation of Hsp70 protein and activation of antioxidant enzymes, in K+ deficient inland saline water, promoting shrimp growth and survival with atleast 50 aqueous K+ supplementation.