Labeo Rohita Fry Research Articles

Effect of vitamin C and mineral enriched diet on growth and survival of Labeo rohita fry

The present study was conducted to understand the effect of vitamin C and mineral enriched diet on growth, survival and mineral accumulation in Labeo rohita fry. The study was conducted for a period of 60 days and it was found that the growth and survival rate increased when local ingredients were fortified with commercially available and commonly used vitamin-mineral mixture, vitamin C and selected mineral elements (Zn, Cu and Mn). The best survival rate (76%) was recorded when feed was supplemented with all the three components (vitamin-mineral mixture, vitamin C and mineral supplement), followed by vitamin-mineral mixture + vitamin C (75.3%) and vitamin-mineral mixture. The Zn, Cu and Mn fortification in the diet also reflected higher deposition of these three minerals in the whole body as well as 38.4% reduction in the cost of production and 152.6% higher revenue generation compared to commercial feed (control). Keywords: Copper, Labeo rohita, Manganese, Vitamin C, Zinc

The study of ameliorative effect of dietary supplementation of vitamin C, vitamin E, and tryptophan on Labeo rohita (Cyprinidae) fry exposed to intense light.

The stress ameliorating effect of dietary supplementation of vitamin C, vitamin E, and tryptophan on rohu Labeo rohita fry was evaluated. Rohu fry (1.1 ± 0.03g) were cultured under five different feeding regimes: enriched with 0.08% vitamin C (D1), 0.02% vitamin E (D2), 1.42% tryptophan (D3), a combination of these three ingredients at similar doses (D4), and control diet (D5). Rohu fry of D5 were divided into two groups-exposed to experimental light (D5FL) and ambient light (114 ± 4lx, D5AL). All fry (except D5AL) were exposed at light intensity of 3442 ± 648lx. Feeding of rohu with enriched diets significantly (P < 0.05) enhanced the survival rate and average weight. A 15-25% higher survival and 1.3-1.8-fold higher average weight were recorded in rohu fed with enriched diet compared to D5FL treatment. Supplementation of vitamin C in diet (D1) of rohu resulted in 4.1-fold and 6.9-fold higher nitric oxide synthase and reduced glutathione (GSH) levels, respectively compared to the D5FL treatment. The tryptophan-enriched diet (D3) showed 5.8-fold higher melatonin and 4.4-fold lower cortisol levels in rohu compared to the D5FL treatment. Significantly (P < 0.05) higher nitric oxide synthase, GSH and melatonin, and lower cortisol, glucose, thiobarbituric acid reactive substances, carbonyl protein, glutathione S-transferase, and glutathione peroxidase levels were found in D4 diet fed rohu compared to the other treatments. Reduced level of stress in D4 treatment resulted in best performance of rohu in terms of less swimming activity and higher survival and growth compared to the other treatments.

Evaluation of immunostimulatory properties of prickly chaff flower Achyranthes aspera in rohu Labeo rohita fry in pond conditions

The immunostimulatory properties of seeds and leaves of Achyranthes aspera (Linn.) was evaluated in rohu Labeo rohita in the pond conditions. Rohu fry (1.9 ± 0.08 g) were introduced in nine hapas (25 hapa−1) set inside a pond. Two test diets enriched with 0.5% seeds (D1) and leaves (D2) of A. aspera and control diet (D3) were fed for 60 days. Then fish were immunized with chicken-RBC and blood and tissue samples were collected on days-7, 14 and 21 after immunization. The average weight was significantly (p < .05) higher in D1 diet fed rohu compared to other two feeding regimes. Specific growth rate and feed conversion ratio were maximum and minimum in D1 diet fed rohu. Serum lysozyme, myeloperoxidase and nitric oxide synthase levels were significantly (p < .05) higher in D1 diet fed rohu compared to others. This group was followed by D2 diet fed rohu. Significantly (p < .05) lower thiobarbituric acid reactive substances (TBARS) and carbonyl protein levels were found in D1 fed rohu compared to others. TBARS and carbonyl protein levels were also lower in D2 diet fed rohu compared to the control one. There were significant (p < .05) up-regulation of lysozyme C, lysozyme G and tumor necrosis factor-α (TNF-α) in hepatopancreas of rohu fed with D1 diet compared to others. This group was followed by the D2 diet fed rohu. The expression of lysozyme C was higher compared to lysozyme G regardless of feeding regimes. In enriched diets fed rohu, the expression of interleukin 10 (IL-10) was significantly (p < .05) lower compared to the control fish. Toll like receptor 4 (TLR-4) was significantly (p < .05) higher in D1 and D2 diets fed rohu compared to other two feeding regimes on day-7 and day-21 after immunization, respectively. Seeds and leaves enhanced the growth, induced the immune system of rohu and gave protection against oxidative stress in pond conditions. Seeds are more efficient compared to the leaves. The information generated from the field study has practical utility.

Validation of growth enhancing, immunostimulatory and disease resistance properties of Achyranthes aspera in Labeo rohita fry in pond conditions

The immunostimulatory and disease resistance properties of herb Achyranthes aspera L. (Amaranthaceae) were evaluated in rohu Labeo rohita in pond. Rohu fry (1.9 ± 0.08 g) were cultured in hapas (25 hapa−1) set inside a pond and were fed with two experimental diets containing 0.5% seeds (D1) and leaves (D2) of A. aspera and control diet (D3). Fish were challenged with Aeromonas hydrophila after 80 days. The cumulative mortality rate of fish was significantly (P < 0.05) higher in D3 (28–48%) compared to others. Average weight was significantly (P < 0.05) higher in D1 (6.5–12.5%) compared to other treatments. Myeloperoxidase and nitric oxide synthase levels were significantly (P < 0.05) higher in D1 and D2 compared to D3. Thiobarbituric acid reactive substances and carbonyl protein levels were significantly (P < 0.05) lower in hepatopancreas and kidney of D1 compared to others. In hepatopancreas, the expressions of lysozyme C, loysozyme G, TNF-α, IL-10 and IL-1β were significantly (P < 0.05) higher in D1 compared to others. This treatment was followed by D2. In kidney, lysozyme G and TNF-α levels were significantly (P < 0.05) higher in D1 and D2 compared to D3. Whereas, IL-10 and IL-1β were significantly (P < 0.05) down-regulated and up-regulated, respectively in kidney of D2. There was up-regulation (P < 0.05) of TLR-4 in hepatopancreas and kidney of D1 and D2 diets fed rohu, respectively compared to others.

Comparative study on cadmium accumulation and its toxicity in fish fry of Labeo rohita and Cyprinus carpio

Comparative study on cadmium accumulation and its toxicity in fish fry of Labeo rohita and Cyprinus carpio

Effects of bisphenol A (BPA) on brain-specific expression of cyp19a1b gene in swim-up fry of Labeo rohita

Estrogen regulates numerous developmental and physiological processes and effects are mediated mainly by estrogenic receptors (ERs), which function as ligand-regulated transcription factor. ERs can be activated by many different types endocrine disrupting chemicals (EDCs) and interfere with behaviour and reproductive potential of living organism. Estrogenic regulation of membrane associated G protein-coupled estrogen receptor, GPER activity has also been reported. Bisphenol A (BPA), a ubiquitous endocrine disruptor is present in many household products, has been linked to many adverse effect on sexual development and reproductive potential of wild life species. The present work is aimed to elucidate how an environmentally pervasive chemical BPA affects in vivo expression of a known estrogen target gene, cyp19a1b in the brain, and a known estrogenic biomarker, vitellogenin (Vg) in the whole body homogenate of 30 days post fertilization (dpf) swim-up fry of Labeo rohita. We confirm that, like estrogen, the xenoestrogen BPA exposure for 5–15 days induces strong overexpression of cyp19a1b, but not cyp19a1a mRNA in the brain and increase concentration of vitellogenin in swim-up fry. BPA also induces strong overexpression of aromatase B protein and aromatase activity in brain. Experiments using selective modulators of classical ERs and GPER argue that this induction is largely through nuclear ERs, not through GPER. Thus, BPA has the potential to elevate the levels of aromatase and thereby, levels of endogenous estrogen in developing brain. These results indicate that L. rohita swim-up fry can be used to detect environmental endocrine disruptors either using cyp19a1b gene expression or vitellogenin induction.

Estrogen-regulated expression of cyp19a1a and cyp19a1b genes in swim-up fry of Labeo rohita

P450 aromatase is the terminal enzyme in the steroidogenic pathway and catalyzes the conversion of androgens to estrogens. The expression of cyp19a1 genes in brain and gonad of Indian major carp, Labeo rohita swim-up fry was measured by quantitative real-time polymerase chain-reaction. Results demonstrated that cyp19a1b and cyp19a1a predominate in brain and gonad respectively. Treatment of fry with an aromatase inhibitor fadrozole for 6days attenuated brain cyp19a1b expression, but not cyp19a1a of gonad. Fadrozole also attenuated brain aromatase activity. Treatment with 17β-estradiol (E2) for 6days resulted in up-regulation of brain cyp19a1b transcripts in a dose- and time-dependent manner, but not cyp19a1a. Whole-body concentration of vitellogenin also increased in response to E2. Altogether, these results indicate L. rohita swim-up fry can be used to detect environmental estrogens either using vitellogenin induction or cyp19a1b gene expression.

Cadmium-induced alterations in bio-chemical constituents of Labeo rohita and Cyprinus carpio fry: A comparative study

Cadmium is a well known heavy metal toxicant which can interfere with metabolism of carbohydrates, proteins and lipids by inhibiting the enzymes involved in the processes. In the present investigation, the effect of cadmium was evaluated on these biochemical constituents in two fresh water fish fry Labeo rohita and Cyprinus carpio. Fish fry of Labeo rohita and Cyprinus carpio were exposed to their respective sub-lethal concentrations (1/5th of LC50), 0.1998 ppm and 4.938 ppm of cadmium for a period of 20days. Total carbohydrates, proteins and lipids were estimated by standard biochemical procedures in control and exposed fish fry. Results showed significant fall in all the biochemical constituents and energy levels of exposed fish fry, indicating that the organism is under toxicant stress.

Food and feeding habits of white-throated kingfisher (Halcyon smyrnensis) in Bangladesh

Food items, preying and feeding activities of white-breasted Kingfisher, Halcyon smyrnensis were studied from September 2008 to September 2011 at Nikunja-1 in Dhaka City Corporation area. A total of 16 species of food items were recorded from the observation. Fishes (more than 60%) were mostly preferred item. The highest preference was fry of Labeo rohita (30.6%). They highly preferred the species belonging to the Family Cyprinidae and Order Cypriniformes. The length of the food items varied from 2.0 to 12.3 cm. Surface dweller species (85.8%) was highly preferred. During preying, they used 0.3 to 2.25 m height, among which the highest preference was 0.9 m (32%). H. smyrnensis targeted the food items before catching while they took 9 sec to 15 min 17 sec. After catching they either engulfed the prey immediately or hold it at their beak for 2 sec to 30 min 30 sec before engulfing. Bamboos found in the water body were mostly preferred (65.9%) as perching places during preying.Bangladesh J. Zool. 42(2): 237-249, 2014

Optimizing Stocking Density of Labeo rohita Fry in Cage Aquaculture System as a Tool for Floodplain Wetland Fisheries Management

Results of a cage aquaculture experiment conducted in Charan beel (a floodplain wetland), district Morigaon, Assam, India to determine optimum stocking density of Labeo rohita fry are discussed. Locally available bamboo and other low-cost construction materials were used for constructing a battery of ten cages (individual cage dimensions 2 × 2 × 2 m and effective water volume 6 m3). Labeo rohita fry (average length 4.0 ± 0.04 cm, average weight 1.05 ± 0.03 g) were stocked at five different stocking densities, viz. 50 (SD1), 100 (SD2), 150 (SD3), 200 (SD4) and 250 (SD5) fry/m3 with two replicates each. Reared fry were fed twice daily with a formulated feed containing 33.16 % crude protein for 2 months. The physico-chemical parameters of sediment were not significantly (p > 0.05) affected by stocking density. Different stocking densities significantly (p 0.05) at SD2 to SD4, but at SD5 there was significant reduction of growth. Feed conversion ratio, protein efficiency ratio, apparent net protein utilization and energy retention value were adversely affected with the increase in stocking densities. The net benefit and benefit-cost ratio were highest in SD4. Therefore, economics of cage culture was considered as the most important criterion in judging SD4 (200 fry/m3) to be the optimal stocking density for raising L. rohita fry in cages in seasonally open floodplain wetlands of Assam, India.

Use of Soybean as Partial Substitute of Fish Meal in the Diets of Rohu, Labeo rohita (Ham.) fry

A 60-day feeding trial was conducted in a static indoor rearing system in 12 glass aquaria to investigate the possibility of using soybean meal protein in lieu of fishmeal as dietary protein source for Labeo rohita fry. Four iso-nitrogenous (30% protein) and iso-caloric (19 kJ/g GE) experimental diets were prepared as: diet 1 (100% fishmeal protein), diet 2 (75% fishmeal protein + 25% soybean meal protein), diet 3 (50% fishmeal protein + 50% soybean meal protein) and diet 4 (25% fishmeal protein + 75% soybean meal protein) and were fed to triplicate groups of 10 fish (per aquarium). Fish were fed two times daily at a rate of 5% of their body weight during the entire experimental period. The feeding ration was adjusted every 10th day through sampling of fish. Growth rate, feed conversion ratio (FCR) and protein efficiency ratio (PER) were significantly higher (P&lt;0.05) in fish fed with diet 2, but those were similar to the diets 1 and 3. Analysis of proximate composition of the whole fish fed with different diets did not show any significant difference (P&gt;0.05). The growth rates, FCR and PER as obtained from the different treatments indicate that fishmeal protein could be replaced up to 50% by soybean meal protein in the diet of L. rohita fry without supplementation of amino acids. DOI: http://dx.doi.org/10.3329/agric.v10i2.13143 The Agriculturists 2012; 10(2) 68-76

Effect of Dietary Supplementation of Achyranthes aspera Seed on the Immune System of Labeo rohita Fry

Labeo rohita (rohu) fry (0.547±0.01 g) were fed one of four diets containing 0 (control), 0.1, 0.5, or 1.0% Achyranthes aspera seed. After 30 days, the fry were immunized with chicken red blood cells (c-RBC). Blood samples were collected 7, 14, and 21 days after immunization. Significantly (p&lt;0.05) higher average weight (2.565±0.02 g) and SGR were were obtained in fry fed the 1.0% diet compared to others. The increase in average weight was directly related to the increasing dose of seed. FCR was significantly (p&lt;0.05) lower in fry fed the 1.0% diet while total serum protein, albumin, and globulin were higher in treated groups than in the unsupplemented control. The antigen-specific antibody titer level was significantly (p&lt;0.05) lower in rohu fed the control diet than in rohu fed the supplemented diets. Titer levels were 32-128, 128-256, 256-1024, and 256-1024 in the 0, 0.1, 0.5, and 1.0% diets, respectively. Serum glutamic oxaloacetic transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), and alkaline phosphatase (ALP) were significantly (p&lt;0.05) higher in rohu fed the control diet than in rohu fed the supplemented diets while myeloperoxidas was lower in the former. Among the treated groups, myeloperoxidase was significantly (p&lt;0.05) higher in rohu fed the 1.0% diet (1.561-2.558, ? 450 nm) than in those fed other diets. The present study documents the immunostimulatory properties of A. aspera seed and finds that a dose of 1.0% might be suitable for rohu fry.

Effect of stocking density and journey length on the welfare of rohu (Labeo rohita Hamilton) fry

The effect of higher packing density and increased duration of transport on the survival and key metabolic enzymes of Labeo rohita fry was investigated. L. rohita fry (length 40 ± 5 mm, weight 0.60 ± 0.13 g) were packed in two different densities 40 and 80 g/l and sampled at 0, 12, 24, and 36 h after packing. Results showed that packing density and length of confinement severely affected the survival of the fry. The whole-body glucose level and the activities of the enzymes, lactate dehydrogenase (LDH), malate dehydrogenase (MDH), glucose-6-phosphatase (G6Pase), fructose-1, 6-bisphosphatase (FBPase), aspartate amino transferase (AST), alanine amino transferase (ALT), and adenosine triphosphatase (ATPase) assayed from the fish whole-body significantly (P < 0.05) increased due to increase in the length of the confinement. However, acetylcholine esterase (AchE) activity decreased significantly (P < 0.05) with increase in the length of confinement. Similarly, higher packing density also significantly (P < 0.05) increased the glucose level and activities of all these enzymes (except AchE). The results revealed that both higher packing density and increased transportation duration mobilize protein resources for glucose production via gluconeogenesis and subsequently activate the glycolysis pathway for energy. The rise in the ATPase activity indicates disruption of the osmoregulatory function and the role of this enzyme in ameliorating it. Overall results suggest that normally practiced packing density of 40 g/l is optimum up to 24-h duration for seed transportation.

Total aromatic amino acid requirement of Indian major carp Labeo rohita (Hamilton) fry

An 8-week growth trial was conducted to quantify the total aromatic amino acid (phenylalanine + tyrosine) requirement of Indian major carp Labeo rohita fry (3.5 ± 0.2 cm; 0.18 ± 0.04 g) by feeding isonitrogenous (40% crude protein) and isocaloric (17.90 kJ g − 1 gross energy) amino acid test diets containing casein, gelatin and l-crystalline amino acids with graded levels of phenylalanine (0.40, 0.65, 0.9, 1.15, 1.4 and 1.65% dry diet, with 1% tyrosine fixed in each diet) to apparent satiation in triplicate groups, twice a day at 07.00 and 17.30 h. Specific growth rate (SGR) 2.53%, feed conversion ratio (FCR) 1.41, protein efficiency ratio (PER) 1.77 and body protein deposition (BPD) 33.69 were significantly ( P < 0.05) higher in fish fed the diet containing 1.15% phenylalanine. Second-degree polynomial regression analysis of SGR, FCR, PER and BPD data indicated the dietary phenylalanine requirement at 1.21, 1.22, 1.22 and 1.16% of the dry diet, corresponding to 3.02, 3.05, 3.05 and 2.90% of the dietary protein, respectively. On the basis of the quadratic regression analysis of SGR, FCR, PER and BPD data, it is recommended that the inclusion of total aromatic amino acid (phenylalanine + tyrosine) in the range of 2.16% (1.16% phenylalanine + 1.0% tyrosine) of the dry diet, corresponding to 5.40% (2.9% phenylalanine + 2.5% tyrosine) of protein to 2.22% (1.22% phenylalanine + 1.0% tyrosine) of the dry diet, corresponding to 5.55% (3.05% phenylalanine + 2.5% tyrosine) of the dietary protein is essential in developing total aromatic amino acid balanced diets for intensive culture of fry L. rohita.

Use of Freshwater Aquatic Plants as a Substitute of Fishmeal in the Diet of Labeo rohita Fry

Use of Freshwater Aquatic Plants as a Substitute of Fishmeal in the Diet of Labeo rohita Fry

Thermal tolerance, growth and oxygen consumption of Labeo rohita fry (Hamilton, 1822) acclimated to four temperatures

A 30 day feeding trial was conducted using a freshwater fish, Labeo rohita (rohu), to determine their thermal tolerance, oxygen consumption and optimum temperature for growth. Four hundred and sixteen L. rohita fry (10 days old, 0.385±0.003 g) were equally distributed between four treatments (26, 31, 33 and 36 °C) each with four replicates for 30 days. Highest body weight gain and lowest feed conversion ratio (FCR) was recorded between 31 and 33 °C. The highest specific growth rate was recorded at 31 °C followed by 33 and 26 °C and the lowest was at 36 °C. Thermal tolerance and oxygen consumption studies were carried out after completion of growth study to determine tolerance level and metabolic activity at four different acclimation temperatures. Oxygen consumption rate increased significantly with increasing acclimation temperature. Preferred temperature decided from relationship between acclimation temperature and Q 10 values were between 33 and 36 °C, which gives a better understanding of optimum temperature for growth of L. rohita. Critical thermal maxima (CTMax) and critical thermal minima (CTMin) were 42.33±0.07, 44.81±0.07, 45.35±0.06, 45.60±0.03 and 12.00±0.08, 12.46±0.04, 13.80±0.10, 14.43±0.06, respectively, and increased significantly with increasing acclimation temperatures (26, 31, 33 and 36 °C). Survival (%) was similar in all groups indicating that temperature range of 26–36 °C is not fatal to L. rohita fry. The optimum temperature range for growth was 31–33 °C and for Q 10 values was 33–36 °C.

Dietary vitamin E requirement, fish performance and carcass composition of rohu ( Labeo rohita) fry

A 90-day feeding experiment was conducted using flow through system to evaluate the requirement of vitamin E for rohu fry in relation to growth performance and to assess the relationship between the dietary vitamin E levels and carcass composition. Five semi-purified diets supplemented with 0, 50, 100, 150, 200 mg vitamin E/kg dry diet as dl-α-tocopheryl acetate were fed to rohu fry (av. wt.±S.E.=0.58±0.01 g) in triplicate groups. At the end of the experiment, growth and dietary performance were evaluated and vitamin E deposition in the tissue, erythrocyte fragility, thiobarbituric acid reactive substances (TBARs) were analyzed. The average net weight gains were 6.82±0.09, 7.38±0.03, 8.20±0.03, 8.07±0.09 and 8.12±0.08 (g/90 days), respectively, for fish fed diets 0, 50, 100, 150, 200 mg vitamin E/kg. The fish fed diets containing less than 100 mg supplemental vitamin E/kg had significantly ( P<0.05) reduced weight gain, feed efficiency and other nutritional indices compared to those fed diets supplemented with vitamin E at 100–200 mg/kg. With the increasing level of vitamin E, both TBARs and erythrocyte fragility values were reduced. Regression analysis of weight gain data using broken-line model indicated a minimum vitamin E requirement of 131.91 mg/kg dry diet. The erythrocyte fragility and TBARs were maximum in fish fed the vitamin E-deficient diet. From the present experiment, it may be concluded that the vitamin E requirement of Labeo rohita fry for optimum growth and other dietary performances is 131.91 mg/kg of dry diet.

Utilization of gelatinized carbohydrate in diets ofLabeo rohitafry

A total of 180 Labeo rohita fry (� 1 g) were distributed into six treatment groups with three replicates each. Six isoenergetic (15.8 kJ g )1 ) diets were prepared with varying levels of protein (CP) and gelatinized carbohydrate (GC), viz. D1: 450 g kg )1 CP, 258 g kg )1 GC; D2: 400 g kg )1 CP, 302 g kg )1 GC; D3: 350 g kg )1 CP, 399 g kg )1 GC; D4: 301 g kg )1 CP, 447 g kg )1 GC; D5: 249 g kg )1 CP, 517 g kg )1 GC and control diet, D6: 400 g kg )1 CP, 468 g kg )1 GC and these were fed to fish at 40 g kg )1 wet body weight per day for 60 days. Highest growth was recorded for fish fed D4, decreasing for D5. Protein utilization, amylase activity and carbohydrate digestibility were significantly positively correlated with GC (P < 0.05) and were highest in fish fed D5. Hypertrophy of hepatic cells was only recorded for D5. Lysine, which may be affected during gelatinization, was estimated in diets and found to be above the minimum level required. Survival rate was unaffected by diet. The results of the present study indicate that a diet containing 450 g kg )1 GC and 300 g kg )1 CP was efficiently utilized by L. rohita fry.

Evaluation of poultry-feather meal as a dietary protein source for Indian major carp, Labeo rohita fry

The suitability of poultry-feather meal (PFM) as a substitute for dietary fish meal protein in the diet of Indian major carp was evaluated. Four experimental diets were formulated with PFM replacing 25, 50, 75, and 100% of the fish meal protein. The control diet was prepared with fish meal as the sole source of protein. All the diets were isonitrogenous with 35% protein. A nine-week trial was conducted under laboratory conditions. There were no significant differences among the growth responses of carp fry fed control, 25% PFM and 50% PFM diets but growth from these diets was significantly higher than from the other diets. The poorest response was observed for the 100% PFM diet. Similar trends were also observed in feed conversion and protein utilization. The results of the present study indicate that hydrolyzed poultry-feather meal can be used at 20% of the diet level (i.e., up to 50% of total dietary protein) for L. rohita fry without compromising growth and feed conversion.

Observations on the use of carbonic acid anaesthesia in fish fry transport

Observations are reported on the use of carbonic acid anaesthesia in fish fry transport. The results indicate that live fry of Labeo rohita (Ham.) could be kept safely (with 95% survival) in the transport medium under a dose of 500 ppm of carbonic acid for as long as 215 h. Controls survived for only < 106 h.