Effect of salinity on the survival, Growth and biochemical composition of Penaeus monodon Fabricius Postlarvae.

Aquaculture has immense potential to augment finfish and shellfish production to partially meet the growing demand for animal protein, It has emerged as the only growth sector of fisheries industries. Aquaculture clearly has the potential to continue to grow rapidly and to make a further substantial contribution to employment and food security, particularly in the rural areas. Penaeid shrimp culture has emerged as a highly profitable investment alternative. In past few decades researchers have gathered considerable information on the biology, production and culture of many of the commercially important shrimps but unfortunately not much attention has been paid to the ecophysiological aspects. In-depth studies on all biotic and abiotic factors are necessary in formulating ecofriendly aquaculture practices. This is particularly important in view of the sudden collapse of shrimp farming in 1994-95 after its rapid expansion in the early 1990'

Nutritional studies on sebae Anemonefish, Amphiprion sebae Bleeker 1853, with special reference To protein and lipid requirements

Anemonefishes or clownfishes command higher price than most other pomacentrids in the marine aquarium fish trade. Commercial production of these reef fishes can generate valuable foreign exchange for the country. The sebae anemonefisi1, Amphiprion sebae Bleeker 1853, is one of the popular marine aquarium fish . At present rearing of the fish relies heavily on live and fresh diets, and formulated diets are seldom used due to inadequate knowledge of the nutritional needs of the different life-history stages. The present study focuses on the nutrition of broodstock, larvae and juvenile stages of the fish in captivity. In order to identify suitable diets for brood fishes the efficacy of six natural and five formulated diets was determined. The natural diets tested were deep sea shrimp, cuttlefish, squid, mature mussel, mussel meat, and a mixed diet of polychaete worm and mussel meat (1 :1). Among the natural diets cuttlefish meat gave significantly higher number of eggs per spawning (1521±264 eggs; mean ± SO, n=9) followed by the deep sea shrimp (1300±445 eggs). Among Ihe five formulated semi-moist diets used, diet CBOs with about 50% protein and 10% lipid, gave significantly higher number (2137±110) of eggs pHr spawning followed by diet CB02 (1683±436 eggs) which had 40% protein and 20% lipid. The number of eggs per spawning was found to decrease significantly when broodfish were fed ad libitum once a day (416128 eggs) compared to those fed ad libitum twice daily (885±55 eggs). Hatchery reared larvae weaned to a dry diet from 3rd week onwards matured and the broodfish spawned successfully in aquaria from 15th month (age of fish) onwards. Feeding experiments using exclusive or combinations of rotifers, Artemia, and Moina showed better survival when the larvae were reared with micro algae and fed rotifers and Artemia. Weaning studies revealed that weaning from livefeed to a dry microbound particulate diet after 3 weeks (21dph) did not Significantly affect survival, though the best age of weaning was found to be 30 days post hatching. Experiments with a purified and semi-purified diet having 50% protein and 6% lipid showed semi-purified diets to be better than purified diets. Analysis of data from protein requirement experiments using semi-purified isocaloric diets showed 46.2% as protein requirement for maximum weight gain in juveniles and 44.9% in terms of SGR. Lipid requirement experiment on juveniles using five isoproteic semi-purified diets showed 10.96% as lipid requirement for maximum weight gain and 11 .05% in terms of SGR. The present study proved the effectiveness of formulated diets in rearing larvae, juveniles and brood stock of the clownfish. The results are significant with enormous application in commercial production of these high value fishes and in promoting indigenous aquarium feed manufacture

Dietary influence on the egg production and larval viability in True Sebae Clownfish Amphiprion sebae Bleeker 1853

Broodstock nutrition is one of the most important research areas in aquaculture. In this study, sebae clownfish was used to find out the influence of diet on reproductive performance parameters like egg production, fertilization rate, hatchability, and larval quality. The feeds used were of marine origin such as squid, cuttlefish, deep sea prawn, immature and mature mussel. The diets were analyzed for their proximate composition, amino acids profile, fatty acids profile and astaxanthin. The sub-adult fishes were collected from wild and conditioned prior to experiment. Data were collected after initial three spawning to achieve stability in egg production and quality. The egg production was found to be significantly influenced by diet and those fed cuttlefish meat gave the highest number of eggs per clutch (1520±260 eggs). The fertilization rate and hatchability were found to be unaffected by the tested diets. The highest larval survival (62.3±7%) after 12 days post hatching was obtained for fish groups fed deep sea prawn. The dietary carotenoid content was also found to influence the egg and larval pigmentation. The result also indicates the importance of dispensable amino acids in egg production. The role of protein, lipids, and essential fatty acids in the broodstock diets for sebae clownfish are also discussed

Ornamental Chasmophytes of Urumbikkara Hills, Western Ghats Region of Idukki District, Kerala, India

The present study on the ornamental chasmophytes in the rocky habitats of Urumbikkara hills of Idukki district, Kerala reveals that, there are about 52 species of ornamental chasmophytic plants belonging to 46 genera and 29 families were collected because of their aesthetic value in both domestic and rock garden practices. These chasmophytes also possess certain biological peculiarities with different interesting adaptations and flower colour which can attract many people for making domestic or rock garden for ornamental purposes and psychological beneficial

Adaptive evolution after duplication of penaeidin antimicrobial peptides

Penaeidin antimicrobial peptides in penaeid shrimps are an important component of their innate immune system that provides immunity against infection caused by several gram-positive bacteria and filamentous fungal species. Despite the knowledge on the identification and characterization of these peptides in penaeid shrimps, little is known about the evolutionary pattern of these peptides and the underlying genetic mechanisms that maintain high sequence diversities in the penaeidin gene family. Based on the phylogenetic analyses and maximum likelihood-based codon substitution analyses, here we present the convincing evidence that multiple copies of penaeidins have evolved by gene duplication, and positive Darwinian selection (adaptive evolution) is the likely cause of accelerated rate of amino acid substitutions among these duplicated genes.fisheries of the country has led to a remarkable increase in fish landings, the problem of by-catch and targeted juvenile fishing is ever increasing. The present analysis shows that the contribution in the form of annual average profit by various craft–gear combinations is often not sufficient to compensate the overall loss generated by the same to the fishery through the harvest of juvenile fishes. Even though the fishermen gain some transient economic incentives from the juveniles landed, the estimated economic loss calculated was at about US$ 19,445 million year−1 from the mechanised as well as motorised sector. Both intergenerational and conventional discounting was applied to show the net present value (NPV) of future loss due to juvenile fishing. Some of the less capital intensive gears also substantially contribute towards the economic deficit caused by juvenile fishing. We suggest that, while considering the ecosystem impacts of accidental by-catch and intentional juvenile fishing, the economic impacts also should be taken into account prior to formulating any management measures. The study provides an insight to the cost of juvenile fishing in a multi-species multi-gear fishery, where a homogeneous management system is ineffective. The possible causes of increased growth overfishing in the country and subsequent economic loss to the industry are also discussed

Influence of salinity on the growth and body composition of juvenile Tiger Shrimp, Penaeus monodon

Giant tiger prawn dominated the global shrimp aquaculture industry before giving way to Pacific white shrimp in the early 21st century. This study evaluated the influence of salinity on the survival, growth and body composition of early juveniles. They were exposed to salinities ranging from freshwater (0‰) to marine (35‰) under ambient rearing conditions. Response parameters like survival, growth and body compositions were tested over the salinity range of 0, 10, 20, 30, and 35 ‰. The survival obtained was above 95% except in freshwater, wherein total mortality was observed by the third week of rearing. Growth was found to vary with salinity significantly and was found to be higher at 20‰ with an SGR of 7.31. Apart from its role in survival and growth, salinity was found to influence body composition. It was observed that body protein and carbohydrate content showed significant variations with the salinity. The body protein content was high at 20 ‰ with 14.45 mg/100mg wet weight, and carbohydrate of 1.01mg/ 100mg at 30 ‰. However, variations in lipid, ash, and moisture content did not have any significant difference. Though found insignificant, the lipid content was higher (2.15 mg/100mg) at lower salinity of10‰. The present study provides insights into the possible impact of rearing environment on the physiological and biochemical changes in this species

Growth response of juvenile clownfish Amphiprion sebae Bleeker, 1853 fed with graded levels of dietary protein

Clown fishes are the most popular marine ornamental species owing to their unique behaviour and symbiotic association with sea anemones. Captive propagation of these fishes is relatively easy; however, the lack of suitable diets influences their survival, growth and colouration. In this study, growth response of juvenile sebae clownfish Amphiprion sebae Bleeker, 1853 was evaluated through a feeding trial. Six iso-caloric experimental diets with graded dietary protein levels of 33.06 (D33), 36.54 (D36), 39.19 (D39), 41.88 (D42), 45.17 (D45) and 47.94% (D48) of dry matter were prepared. Lipid content of approximately 6% was maintained for all dietary treatments. The study was conducted for nine weeks in triplicate to evaluate survival, growth and feed utilisation. Fishes fed with diet D36 did not present any mortality; those fed diets D39, D45 and D48 had a lower survival with 86.7%, without significant differences among the treatments. However, weight gain, specific growth rate (SGR) and feed conversion efficiencies showed a significant difference among the treatments (p<0.05). Weight gain and SGR of sebae clownfish increased gradually among tested diets and peaked at D45 (697.28 mg and 3.84). A sharp decline in weight gain and SGR (486 mg and 3.39) was observed with the replicates fed with D48. Feed conversion ratio (FCR) and protein efficiency ratio (PER) were superior with diets D42 (1.40 and 1.71) and D45 (1.60 and 1.38). The results of the present study revealed higher growth when fed with dietary protein level of 45%. The second-order polynomial regression on SGR and weight gain suggested an optimal dietary inclusion at 44.9 - 46.2%. Based on these results, it can be inferred that juvenile sebae clownfish has a higher dietary protein requirement of about 45%. However, the study also suggested the efficacy of diets having 36% protein and 6% lipid for healthy aquarium upkeep of sebae clownfish. These findings will be beneficial for the commercial propagation and maintenance of clownfishes

Synthesis, spectral and structural studies of transition metal complexes of N(4)-substituted semicarbazones

The thesis is an introduction to our attempts to evaluate the coordination behaviour of a few compounds of our interest. Semicarbazones and their metal complexes have been an active area of research during the past years because of the beneficial biological activities of these substances. Tridentate NNO semicarbazone systems formed from heterocyclic and aromatic carbonyl compounds and their transition metal complexes are well-authenticated compounds in this field and their synthesis and characterization are well desirable. Hence, we decided to develop a research program aimed at the synthesis and characterization of novel semicarbazones derived from 2-benzoylpyridine and 2-acetylpyridine and their transition metal complexes. In addition to various physicochemical methods of analysis, single crystal X—Ray diffraction studies were also used for the characterization of the complexes.Department of Applied Chemistry, Cochin University of Science and Technolog

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Not AvailableBroodstock nutrition is one of the most important research areas in aquaculture. In this study, sebae clownfish was used to find out the influence of diet on reproductive performance parameters like egg production, fertilization rate, hatchability, and larval quality. The feeds used were of marine origin such as squid, cuttlefish, deep sea prawn, immature and mature mussel. The diets were analyzed for their proximate composition, amino acids profile, fatty acids profile and astaxanthin. The sub-adult fishes were collected from wild and conditioned prior to experiment. Data were collected after initial three spawning to achieve stability in egg production and quality. The egg production was found to be significantly influenced by diet and those fed cuttlefish meat gave the highest number of eggs per clutch (1520±260 eggs). The fertilization rate and hatchability were found to be unaffected by the tested diets. The highest larval survival (62.3±7%) after 12 days post hatching was obtained for fish groups fed deep sea prawn. The dietary carotenoid content was also found to influence the egg and larval pigmentation. The result also indicates the importance of dispensable amino acids in egg production. The role of protein, lipids, and essential fatty acids in the broodstock diets for sebae clownfish are also discussed.Not Availabl