首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
Culture water and various tissues from carps (Catla catla (Hamilton), Labeo rohita (Hamilton), Cirrhinus mrigala (Hamilton) and Cyprinus carpio L., respectively) grown in an aquaculture pond in Tiruchirappalli, India, were examined for the presence of Enterobacteriaceae. Bacterial species isolated from the intestinal tract of the four fish species were similar to those isolated from the pond water. More than 50% of the total bacterial population identified in both the pond water and fishes intestinal tract were Escherichia coli and Pseudomonas aeruginosa. The presence of these bacteria suggests the need for following strict hygiene during handling and processing fish to prevent the transfer of potentially pathogenic bacteria to humans. Additionally, it stresses the need for a code of practice for fish growers in aquaculture systems for safety reasons.  相似文献   

2.
This paper describes an experiment using a recirculatory-filtering system operating in two rectangular cemented ponds (160 and 190 m2, 1.5 m deep) to rear fry (25 mm–50 mm) of the major Indian carp species Labeo rohita (Hamilton) and Catla catla (Hamilton) to fingerlings (100 mm–125 mm). These operations were concluded in both the species in 32 days at stocking densities of 0.46 million/ha and 0.55 million/ha, and showed survival rates of 96.6% and 84.4% respectively. In the presently followed practices of modern fish culturists, corresponding operations in earth ponds usually take 90 days and have a stocking density of 0.2 million/ha with survival rates more or less similar to those obtained in the recirculatory-filtering system. If followed by industry, the technique described will enable production of major Indian carp fingerlings with great saving in time, the use of water and the space occupied by the production system. These advantages greatly enhance the economic viability of rearing carp fingerling in India.  相似文献   

3.
A sustainable semi-intensive pond aquaculture technology including major carp species as cash-crop and small indigenous fish species (SIS) as food for the farmers' families is being optimized in Bangladesh. The inclusion of silver carp (Hypophthalmichthys molitrix), a cheap large species affordable by poor farmers, is now being considered. As part of a study on the effects of this filter feeder on polycultures including the large carps rohu (Labeo rohita), catla (Catla catla) and common carp (Cyprinus carpio) and the SIS punti (Puntius sophore) and mola (Amblypharyngodon mola), an experiment was carried out under farm conditions to test the effects of silver carp and of each SIS species on the growth, survival and yield of the large and small species and on pond ecology.The experiment was performed in 38 farmers' fishponds of different sizes, from 220 m2 to 1200 m2. The results show that the larger the fish pond the better rohu performance, the larger punti fry weight and the lower punti fry harvested biomass. Pond size did not affect other fish species. The addition of 250 mola and/or punti per 100 m2 fishponds affected rohu and catla and did not affect common and silver carps. The addition of mola alone reduced rohu's parameters by 15%. The addition of SIS in the three combinations tested (250 mola, 250 punti, 125 of each species) reduced catla's parameters by 20-24%. Punti fry were larger when both SIS were stocked and punti fry biomass was larger when only punti were present. Total mola harvested biomass and yield were larger when the entire SIS stocked were only mola.The addition of 10 silver carp over the 99 large carps stocked per 100 m2 fishponds negatively affected rohu and catla growth and yield by about 15-21% and 45-50% respectively but not their survival, did not affect common carp performance, did not affect punti and mola reproduction in the ponds, reduced punti yields by 25%, reduced mola performance by about 35%, and silver carp own biomass increased total yield and total income in about 12% each. These effects are explained and discussed considering fish interactions through the food web. The decreased income from selling the more expensive large carps is more than compensated by that obtained from silver carp, which allows the option to the farmer to sell part of the silver carp to complete the cash income that would have been obtained from large carps only if silver carp would not be stocked, and consume the rest with the family.  相似文献   

4.
ABSTRACT

Catla, Catla catla, and rohu, Labeo rohita, fry were cultured at 6,667,8,333, and 10,000/m3 in 15-L aquaria in recirculating systems for 30 days. Larvae were fed with exogenous live plankton. Cultures at 6,667 and 8,333 larvae/m3 showed significantly (P <0.05) higher survival and growth than larvae stocked at 10,000 larvae/m3 for both species. Food was more efficiently used in low stocking density, as evident from the significantly (P <0.05) lower values of feed conversion ratio in lower density compared to those for high stocking density. Specific growth rate of both species was high in the early stage and gradually declined along with the ontogenic development. Dissolved oxygen level was higher in the low density system than in the high density one. Values of phosphate and COD increased during the experiment. Ammonia, nitrite, phosphate, and COD levels were significantly (P <0.05) higher in the 10,000 larvae/m3 density system than in the other two systems for both species. Considering the survival and growth of fish and values of water quality parameters, it appears that stocking density can be raised up to 8,333 larvae/m3 with a recirculating system for both catla and rohu.  相似文献   

5.
DNA fingerprints were obtained in three species of commercially important freshwater fishes, Labeo rohita (Hamilton). Catla catla (Hamilton) and Oreachromis mossambicus (Peters), using Bkm 2(8) and M13 multilocus probes. Bkm 2(8) gave a higher number of bands when compared with M13. However, the number of bands obtained by each probe in O. mossambicus was similar. The higher band-sharing coefficient observed in this species may be attributed to inbreeding as it arose from a small founder population. In L rohita and C. catla, the Bkm 2(8) detected similar DNA fingerprints when two enzymes Hinfi and Taqi were used. The M13 probe also gave similar fingerprints with three restriction enzymes (Hinfi, Taqi, Alui). Comparison of the DNA fingerprints obtained by Bkm 2(8) and Ml 3 showed that these two probes detected different alleles. The overall similarity of the DNA fingerprint patterns in L. rohita and C. catla may be due to their genetic closeness as indicated by their same chromosome number, C-value and their ability to produce fertile hybrids. A similar argument also holds true for the Oreochromis species where interspecies hybridization results in fertile offspring.  相似文献   

6.
Composite fish culture of the Indian major carp, Catla catla, Labeo rohita and Cirrhinus mrigala together with the Chinese silver carp Hypophthalmichthys molitrix and grass carp Ctenopharyngodon idella and the Indonesian strain of common carp (Cyprinus carpio communis) was carried out in experimental ponds in 1971–1972 and 1973–1974. The management techniques adopted aimed at high yields of marketable fish (around 1 kg) in 1 year.In the first year, production varied from 3 889 to 5 600 kg/ha/year and this rose to an average of 8 200 kg/ha/year with a maximum of 9 389 kg/ha/year in the second year. The important changes made to the management schedule in 1973 were increased stocking density, greater use of feed and fertilizers, and provision of more weeds for grass carp.The experimental studies demonstrate the practicability of raising large crops of healthy marketable fish in India.  相似文献   

7.
The present study investigates the success of stocking fingerlings of Indian major carps ‐Gibelion catla (Hamilton), Labeo rohita Hamilton and Cirrhinus mrigala Hamilton – to enhance fish yield in 58 small reservoirs in Odisha State, India. Fish stocking and yield data were collected from State Fisheries Department, Odisha. The relationships between area, stocking density and fish yield of different size groups of reservoirs were assessed using the Pearson correlation coefficient (r). Fish yield increased significantly (p < 0.05, t‐test) from 204 kg/ha/year in 2012–13 to 323 kg/ha/year in 2013–14 due to adoption of CBF. The corresponding per capita fish production increased from 398 kg fisher?1 year?1 to 702 kg fisher?1 year?1 benefitting more than 8,000 fisher households. Reservoirs in the size group 100–500 ha showed the highest response of fish yield with respect to stocking of fingerlings. The size of fingerlings at stocking and area of the reservoir had greater impact on enhancing fish yield. Stocking had a profound positive impact on fish yield. This study forms a baseline evaluation of the impact of stocking on small tropical reservoirs in India. It also recommends management measures and discusses issues, and the way forward for sustainable fisheries enhancement in small tropical reservoirs in eastern India.  相似文献   

8.
Aquatic weeds are one of the major unconventional feed ingredients tested for aquafeed formulation. Tannin content in the water lettuce, Pistia, has been quantified (26.67 mg g−1; dry weight) and graded levels of which (12.5–200 μg) have been incorporated in the reaction mixtures to evaluate any change in the in vitro activity of the principal digestive enzymes from the three Indian major carps (IMC), namely rohu (Labeo rohita), catla (Catla catla) and mrigala (Cirrhinus mrigala). Result of the experiment revealed that the Pistia tannin (PT) significantly inhibit/lower the activities of the digestive enzymes from three IMCs in a dose-dependant manner, even at very low concentration. Significant variation in the reduction of the enzyme activities was noticed between the three fish species, as well as between the three enzymes studied. Among the three species studied, digestive enzymes from L. rohita were found to be the most sensitive to the PT, whereas enzymes from C. catla were found to be comparatively least affected. On the other hand, protease and lipase activities were comparatively more affected than the amylase activity. The results of the study suggest that more stress should be given on the elimination of tannin while incorporating feed ingredients of plant origin in fish diets.  相似文献   

9.
The innate immune system, particularly the external body surface, plays a frontier role in protecting fish from relevant infections. The present study is aimed at understanding and comparing the mucosal immunity of Indian major carp, that is, Labeo rohita, Catla catla and Cirrhinus mrigala, by evaluating different immune parameters such as protein content, lysozyme, myeloperoxidase, proteases and alkaline phosphatase activity in the skin mucus. The protein content of mucus sample of these species was compared, and the highest protein content was found in C. catla among the three Indian major carp species. The levels of proteases (40 ± 0.211 units/ml) and myeloperoxidase OD450 nm (1.525 ± 0.108) were found to be highest in the skin mucus of C. catla. However, lysozyme levels were highest in the skin mucus of L. rohita (10.95 ± 0.330 μg/ml), and C. mrigala had the highest alkaline phosphatase activity (30.74111 ± 0.680 U/l). Besides the enzyme activities, the epidermal mucus samples of three Indian major carp species were also tested and compared for the antibacterial activity against seven bacterial strains. Skin mucus of C. catla showed highest antibacterial activity among the three Indian major carps against all the seven bacterial strain, except that Micrococcus lysodeikticus and Vibrio cholerae, however, showed highest activity against mucus of C. mrigala. Also, the epidermal mucus from all the three species successfully agglutinated three freshwater pathogens, viz. Aeromonas hydrophila, Pseudomonas fluorescens and Edwardsiella tarda, with agglutination titres being the highest for Labeo rohita for all the pathogens. The epidermal mucus samples from the Indian major carp species showed haemagglutination activity and successfully lysed human, chicken and goat RBCs showing highest activity in C. catla. These results provide information for a better understanding of the role of epidermal mucus and its components in the innate immune system of Indian major carps.  相似文献   

10.
The present study was undertaken with a view to compare the precision and reliability of the age readings obtained from different bony structures of some important freshwater teleosts viz., Labeo rohita (Hamilton), Catla catla (Hamilton) and Channa marulius (Hamilton). Standard procedures were followed to prepare and study the age structures. In L. rohita and C. marulius percent agreement between reader's age estimates was highest for scales, i.e. 96.3% and 90.5%, respectively and in C. catla percent agreement was highest (93.3%) for opercular bone. When scale ages were compared with other alternative structures viz., otoliths, opercular bone, vertebral centra and dorsal fin rays, percent agreement was found highest between scale and opercular bone age estimates (77.8%) in L. rohita and between scale and otoliths (94.8%) in C. marulius. In case of C. catla highest percent agreement was found between opercular bone and scale age estimates. In L. rohita each of the ageing structure showed significant (P < 0.05) underestimation of age in comparison to scales. In C. catla mean age estimates from opercular bone were comparable (P > 0.05) to the values obtained from all other structures except dorsal fin rays. In C. marulius mean age estimates from scales were comparable (P > 0.05) to those from all other structures except from dorsal fin rays. Results indicated scales to be the most suitable structure for ageing L. rohita and C. marulius and opercular bone for C. catla. However, in C. catla also scales may be used as a non-destructive method of age estimation with satisfactory results.  相似文献   

11.
In this study, the efficacy of biofloc system was assessed for culturing Indian major carps, e.g., rohu (Labeo rohita), catla (Catla catla), and mrigal (Cirrihinus mrigala) at varied stocking densities (STD) from 4.28, 8.57, and 12.85 fish m−3 of tank volume. Biofloc system could efficiently remove inorganic nitrogen from culture water and substantially improved the growth parameters of fishes as compared to the control system without the application of biofloc. Among different STDs in biofloc system, water quality and floc formation were noted to be higher with a STD of 4.28 fish m−3 and the average concentration of NH4 – N, NO2 – N and NO3 – N of 0.61 mg L−1, 0.35 mg L−1 and 1.8 mg L−1, respectively was recorded lowest as compared to the other STD. As a result, catla and rohu could achieve a specific growth rate of 1.1 % day−1 and 0.98 % day−1, respectively. However, in the other two STDs, the respective concentrations were noted in the range of acceptable water quality, and the growth rates were satisfactory. It can be concluded that the biofloc system is efficient to culture IMC in polyculture mode amd therefore, can be directly applied in scaled-up culture modules.  相似文献   

12.
Labeo rohita (139.92 ± 0.76 mm/24.33 ± 0.45 g) was reared for 92 days in floating square cages (10 m2 area, 1.5 m height) in a pond (2 ha) at six stocking densities (5, 7.5, 10, 15, 20 and 25 fish m?2) each with 3 replicates. Fish were fed daily once in the morning with rice polish and groundnut oil cake (1:1) in dough form at 3 % of the total body weight. Survival ranged from 96 to 100 % in different stocking densities. Final average body weight, average body weight gain, mean daily body weight gain and SGR decreased (P < 0.05) with increasing stocking density. Conversely, final biomass, biomass gain and FCR increased (P < 0.05) with increasing stocking density. The highest growth rate of fish could be achieved up to 60 days at 5 fish m?2 and 92 days at other densities. The reduced growth rate at 10–25 fish m?2 for 60 days of culture indicated that stress is related to size and density of the fish, suggesting that utmost care is required to reduce the stress at high densities. Maximum production and profit was observed at the highest stocking density. Non-lethal levels of water and soil qualities at different sites (cage premises, and 20 and 200 m away from cage area) suggested that cage aquaculture could be done safely covering 0.9 % of pond area. Production of advanced fingerlings in cages was found a viable alternative to their culture in pond.  相似文献   

13.
The objective of the present study was to evaluate the effect of plant‐ingredient‐based feeds on fillet fatty acid profiles, proximate composition, carcass traits, and sensory characteristics of three Indian major carps (IMCs), Catla catla, Labeo rohita, and Cirrhinus mrigala, when fed at different levels of their body weight. An experimental feed was prepared with only plant ingredients. The IMCs were fed twice daily at 1.0, 1.5, 2.0, and 2.5% of their body weight for 150 d in 0.06‐ha earthen pond polyculture systems. The maximum growth and best feed utilization was achieved with feeding at 2% of fish biomass in the ponds. Fillet yield and lipid recovery increased significantly (P < 0.05), with increasing feeding level up to 2% of body weight and plateaued thereafter. In fillets, eicosapentaenoic acid (20:5n‐3) and docosahexaenoic acid (22:6n‐3) concentration increased with increasing feeding levels. Carcass traits, sensory characteristics, and consumer acceptance of IMC fillets were not influenced by feeding plant‐ingredient‐based feeds at different feeding rates.  相似文献   

14.
Isolation and enumeration of phytase‐producing bacterial flora in the foregut and hindgut regions of the gastrointestinal tracts of 10 culturable freshwater teleosts of different feeding habits, namely rohu (Labeo rohita), catla (Catla catla), mrigal (Cirrhinus mrigala), bata (Labeo bata), kalbasu (Labeo calbasu), Nile tilapia (Oreochromis niloticus), climbing perch (Anabas testudineus), common carp (Cyprinus carpio), silver carp (Hypophthalmichthys molitrix) and grass carp (Ctenopharyngodon idella), have been carried out. Microbial culture of the gut mucosa on selected nutrient media following the enrichment culture technique was performed for bacterial isolation. The bacterial isolates were screened on the basis of their enzyme‐producing ability. The bacterial population on the tryptone soya agar (TSA) plate was maximum in the hindgut region of bata, followed by mrigal and minimum in the foregut region of Nile tilapia. In modified phytase screening medium (MPSM), phytase‐producing strains were recorded at higher densities in the foregut region of mrigal and grass carp and minimum in the foregut region of bata. In case of the hindgut, maximum phytase‐producing strains were present in grass carp and mrigal and minimum in rohu. In general, in MPSM, the bacterial population was lower in the hindgut region of all the 10 species of fish examined. The phytase‐producing ability of the selected 31 strains (16 from the foregut and 15 from the hindgut region) was determined by clearing zones on phytate‐containing plates. Among these isolates, 22 strains (12 from the foregut and 10 from the hindgut region) were selected as potent phytase producers according to a quantitative enzyme assay. The highest phytase activity was observed in the bacterial strains LF1 and LH1 isolated from the fore and the hindgut regions of rohu respectively. Both the strains were identified as Bacillus licheniformis on the basis of phenotypic characteristics as well as 16S rDNA sequence analysis.  相似文献   

15.
Maize gluten (a byproduct from the starch industry) was used at four different levels (5, 10, 15 and 20% w/w) replacing the fish meal, a component of supplementary diet, under a semi-intensive culture system. The impact of different diets on the physico-chemical parameters of water, growth and flesh quality of catla, Catla catla; rohu, Labeo rohita; and mrigal, Cirrhina mrigala was studied. Growth in terms of body weight gain was highest when fed a diet having 5% maize gluten (replacing fish meal at 25% level) for all the fish species. However, incorporation of maize gluten at higher levels led to decline in growth, since maize gluten is deficient in essential amino acids like methionine, lysine and threonine, etc. The flesh quality in terms of total protein, total lipid, total sugar, moisture and total ash was also determined at the termination of the experiment to see whether there was any significant variation with the incorporation of maize gluten or not.  相似文献   

16.
Antinutritional effects of phytic acid (myoinositol hexaphosphate, IP6) on growth and digestibility in fish have been reported. However, specific effect of IP6 on the digestive enzymes in fish has not been addressed. In this study, inhibitory effect of synthetic IP6 (Phytic acid sodium salt, 90% purity) on the activity of the digestive protease and α‐amylase in rohu, Labeo rohita; catla, Catla catla; and mrigal, Cirrhinus mrigala has been investigated in vitro. Graded levels (12.5, 25, 50, 100, 150, and 200 µg/mL) of IP6 were added to the reaction mixtures containing enzyme extracts and substrate solution in triplicate to detect any change in enzyme activity. Results of the experiment revealed that IP6 significantly inhibit/lower activities of the digestive enzymes in a dose‐dependent manner, as evident from the regression equations (F values significant at P < 0.001 level). Apparently, irrespective of the fish species studied IP6‐induced inhibition of α‐amylase activity was greater than protease activity. Among the three fish species studied, C. mrigala appeared to be more sensitive to IP6 for both α‐amylase and protease activity. Enzyme activity was least affected in C. catla. Results of the study might raise concern while incorporating IP6 rich plant‐derived feed ingredients in aqua feed preparation.  相似文献   

17.
High consumer preference together with its polyculture potential has undoubtedly driven Rohu (Labeo rohita) and Catla (Catla catla) to top the list of the most preferred fishes among the Indian major carps. Commonly found in these fishes are hybrids that can be natural or man-made. Increasing emphasis on biodiversity issues has necessitated proper stock management of these through molecular genetics techniques. Also with few morphological differences that can be used to differentiate wild types and hybrids properly, the problem demands a straightforward molecular approach. Here, we report a simple PCR-based technique that can differentiate the hybrid variety from wild types easily using three different microsatellite markers. Three sets of primers were used to amplify three different microsatellite markers from the genomic DNA isolated from pectoral fins. When the PCR products using all three primer sets were analyzed, ‘hybrid–Rohu’ could be distinguished from wild types. Whereas the hybrid–Rohu DNA yielded specific PCR products with all three primer pairs, only two PCR products were obtained either from wild-type Catla DNA (by primer sets 1 and 2) or from wild-type Rohu DNA (by primer sets 1 and 3). This study clearly demonstrates that a simple PCR-based technique will help the fish breeders and hatcheries to identify and differentiate suspected hybrid–Rohu carp from the wild types within a few hours.  相似文献   

18.
Polyculture of olive barb with indigenous major carps was carried out for 8 mo at different densities in earthen ponds. All the experimental ponds were stocked with fingerlings of major carps viz., catla, Catla catla, and rohu, Labeo rohita, at the rate of 3750/ha each. In addition, olive barb, Puntius sarana, was stocked at the rate of 10,000, 12,500, and 15,000 fingerlings/ha in treatment‐1 (T1), treatment‐2 (T2), and treatment‐3 (T3), respectively. Fish in all the ponds were fed with supplementary feed comprising of rice bran (70%), mustard oil cake (25%), and fish meal (5%) at the rate of 3–6% of the estimated body weight. Physicochemical parameters and plankton populations of pond water were within the acceptable range for fish culture. The mean final weight, weight gain, and specific growth rate of catla were very similar in all the treatments while those for rohu and olive barb were significantly higher in T1 than in T2 and T3. The gross and net productions in T1 were significantly higher than in T2 and T3. The net benefit was also highest in T1 followed by T2 and lowest in T3. Under the conditions of this experiment, growth, production, and benefits were greatest at a stocking density of olive barb at 10,000/ha in polyculture with other major carps.  相似文献   

19.
To assess the compensatory growth, a 10‐month pond experiment was conducted in which three species of Indian major carps, viz. Catla catla, Labeo rohita and Cirrhinus mrigala (1 : 1 : 1), were stocked at 7500 ha?1 and the fish were subjected to different restricted feeding and refeeding protocols, viz. Control (C): Continuously fed for 10 months; Treatment‐1 (T‐1): Initial supplementary feeding for 2 months+ No supplementary feeding for 1 month + Refeeding for 7 months; Treatment‐2 (T‐2): Initial supplementary feeding for 2 months + No supplementary feeding for 2 months + Refeeding for 6 months; and Treatment‐3 (T‐3): Initial supplementary feeding for 2 months + No supplementary feeding for 3 months + Refeeding for 5 months in triplicate ponds. At the end of experiment, 100% growth compensation was achieved in T‐2 for all the three carp species. Among all treatments, higher weight gain, PER and PPV and lower AFCR were also recorded in T‐2, resulting in maximum fish production. The restricted feeding had significant effect (P < 0.05) on whole body chemical composition of fish. From this study, it is concluded that in 10‐month pond culture of carp in fertilized pond, the T‐2 would be the best and most economic feeding strategy.  相似文献   

20.
The major Indian carps, rohu (Labeo rohita), catla (Catla catla) and mrigal (Cirrhinus mrigala), were hitherto known to breed only once a year—during the monsoon season—either in their natural habitat or by hypophysation in captivity. It has been found possible to mature and induce these carps to spawn twice in the same season, within an interval of about 2 months, and thus augment the spawn production. The technique in brief is as follows. (i) The fish are bred by hypophysation early during the monsoon, in June. (ii) After the first spawning, prophylactic measures are adopted. (iii) The fish are fed supplementary feed consisting of groundnut oil cake and rice bran at a ratio of 1 : 1 and 2–5% body weight of the fish. The spent fish, under favourable weather conditions, were found to mature for a second time and were ready for a second spawning, using hypophysation, in about 2 months. This finding is a breakthrough in the field of fish culture at it helps to obtain more spawn from the same specimens in one season. These results demonstrate the possibility of extending this practice to other cultivated species and thereby augmenting the supply of quality fish seed.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号