जल कृषि प्रजाति के आनुवंशिक सुधार के लिए जैव प्रौघोगिकी उपकरणों का प्रयोग

कृपया पूरा लेखा पढ

क्रस्टेशियाइयों में जैव प्रौद्योगिकी हस्तक्षेपों से प्रजनन

कृपया पूरा लेखा पढ

Carbonic anhydrase and Na/K-ATPase activities during the molt cycle of low salinity-reared white shrimp Litopenaeus vannamei

Changes in hemolymph osmolality, ion concentrations, and enzymatic activities of carbonic anhydrase (CA) in the gills and epidermal tissue, and Na/K-ATPase in the gills during the molt cycle were investigated in the white shrimp Litopenaeus vannamei. Hemolymph osmolality was high in the intermolt and early premolt stages, but started to decrease prior to ecdysis through to postmolt stages A and B. Changes in Na? and Cl- ion concentrations paralleled those in hemolymph osmolality. CA activity levels in the anterior and posterior gills were low at intermolt stage C0 and premolt stage D0, and maximum at premolt stage D3. In the epidermal tissue, activity was relatively high at intermolt stage C0 and premolt stage D0, but fluctuated towards premolt stage D3 and postmolt stage A. On the other hand, Na/K-ATPase activity in the gills decreased between intermolt stage C0 and premolt stage D2, but increased at premolt stage D3 and postmolt stage A. The changes in patterns of CA activity during the molt cycle suggest that CA may be involved in supplying counter-ions for Na? and Cl- uptake during molting. Branchial Na/K-ATPase appears to be involved in producing local osmotic gradients in order to support water influx across the epithelium

सीप गठन की प्रेरणा के लिए समुद्री द्विकपाटी मोलस्क के मैन्टिल ऊतक के पात्रेन संवर्धन का प्रयोग

In vivo culture of mantle tissue of bivalve molluscs for induced pearl productio

Oyster picking in Alambarai Creek

During the course of a survey conducted in the first week of June by ferry boat in the Alambarai creek (Chinna Cuddalore area, Tamil Nadu) to study the availability of fish seed suitable for cage culture operations, clam beds (Meretrix casta) and oyster beds (Crassostrea madrasensis and Saccostrea cucullata) were observed in the creek. There is a thriving sustenance fishery for oysters in the creek. Oyster picking is a trade practiced year-round in the area by a group of about 15 people, predominantly women of Kotte Kadu village, who do not belong to the fishermen community

Biochemical responses of juvenile rock spiny lobster Panulirus homarus under different feeding regimes

An experiment was conducted to evaluate the biochemical changes and digestive enzyme activities of juvenile Panulirus homarus lobsters kept under three different feeding regimes, namely starvation, feeding with live clam and feeding with formulated feeds. A marked reduction in the hepatosomatic index (HSI) and a decrease in levels of both protein and lipid in the hepatopancreas of starved animals were observed at the end of the trial. Results indicate that hepatopancreas forms the primary organ for mobilization of energy reserves and that both proteins and lipids are mobilized as energy sources during starvation. Starvation induced a significant increase in proteolytic digestive enzymes of the hepatopancreas. In the group fed on formulated diet, amylase activity was found to be high, probably in response to the high carbohydrate content of the feed used in the present study. These animals also had a significantly lower free amino acid content in the hepatopancreas Histological studies showed that feeding with formulated diet-induced vacuolation in the hepatopancreas caused by hypertrophy of B cells, and a distinct thickening of the lumen walls. These results suggest difficulty in metabolism and mobilization of nutrients absorbed from formulated feeds in tropical spiny lobsters

Manipulation of fatty acids in the estuarine clam Meretrix casta (Gmelin, 1791) by supplementation with the microalgal diet, Isochrysis galbana

The present study evaluated the changes in fatty acid profile of the estuarine clam Meretrix casta, an important food organism used in the larval rearing of scyllarid lobsters, after supplementation with the microalgal species Isochrysis galbana. The uptake and assimilation of lipids from the microalgal feed were verified by gas chromatographic analysis of fatty acids in the clam tissues after eight days of feeding with I. galbana. Increase in concentrations of polyunsaturated fatty acids (PUFA), in particular docosahexaenoic acid (DHA, C22:6n3) and C18:2n-6, was observed in clams supplemented with I. galbana. Changes in monounsaturated fatty acid (MUFA) composition were less marked and related to the increasing proportions of C18:1, after supplementation. Feeding with I. galbana also induced a decrease in the proportion of saturated fatty acids, which was related to decrease in proportions of both C16:0 and C18:0. Although the fatty acid composition showed significant differences, the gross lipid content of the clam tissues did not seem to be excessively influenced by the algal feeding. Tissues from clams supplemented with I. galbana are being evaluated as feed for sand lobster larval trials

Cell Culture and Gene Expression Studies in Relation to Biomineralization in the Black-lip Pearl Oyster, Pinctada margaritifera

Nacre is composed of aragonite platelets and organic material formed by molluscs as inner shell layer through biomineralization process, and mantle epithelial cells control nacre formation. A primary culture of granulated epithelial cells was established from mantle tissue of Pinctada margaritifera, through a process of continuous sub-culturing at 28°C in yeast supplemented sea water culture medium. Nuclear beads were placed in culture wells containing semi-solid agar medium and incubated in vitro with cultured granulated epithelial cells in order to evaluate the nacre secretion. On visual observation, a brown coloration was observed on the surface of the bead after 7-10 days. Evaluation of the surface of the nuclear beads by scanning electron microscopy (SEM) after 60 days of incubation revealed a good brick and mortar pattern, characteristic of nacreous layer formation. A lustrous hue was also seen to develop on bead surfaces after this stage. SEM images of a cross section of the nacre-coated bead showed a pattern of arrangement of aragonite tablets similar to that seen in cross sections of the nacre layer of shell of molluscs. The functional ability of cultured granulated epithelial cells was further confirmed by detecting gene expression of two matrix proteins, nacrein and amorphous calcium carbonate binding proteins (ACCBP), which play an important role in formation of the nacreous layer, in both cultured cells and in native mantle tissue. Amplification products for nacrein (480 bp) and ACCBP (500 bp) genes were obtained in both native mantle tissue and in vitro cultured mantle epithelial cells. There was good correlation between the expression patterns of the two genes in in vitro cultured cells and in native mantle tissue, signifying that cultured mantle epithelial cells retain their functional characteristics of biomineralization

Microstructural Analysis of in vitro Nacre Formation on Shell Bead and Titanium by Cultured Mantle Tissue of Pearl Oyster, Pinctada fucata

Nacre, the inner iridescent layer of molluscan shells is an organic-inorganic composite material. The layered arrangement of platelet-shaped CaCO3 crystals and organic matrix in a brick-and-mortar structure makes it a strong, resilient, and iridescent material. In-vitro nacre formation on shell bead by the mantle tissue of the pearl oyster, Pinctada fucata has already been reported. The current study details a microstructural investigation and comparison of in vitro nacre deposition by the mantle tissue of pearl oyster, P. fucata on shell bead and titanium plates. Nacre platelets were observed by Scanning Electron Microscopy (SEM) and its CaCO3 composition was determined by Energy Dispersive X-Ray Spectroscopy (EDS) analysis on both shell bead and titanium plate. Nacre deposits displayed the typical lamellar brick and mortar” arrangement composed of aragonite platelets which form the “bricks” and organic matrix that forms the “mortar”. Details of the microstructure of in vitro nacre formed by the mantle tissue of pearl oyster were elucidated for the first time by Atomic Force Microscopy (AFM). Further, the deposition of nacre on titanium proves its potential application as a suitable biomaterial in dental and bone implants, due to its biocompatibility towards regeneration

Evaluation of different media for cell proliferation in mantle tissue culture of the green mussel, Perna viridis (Linnaeus, 1758)

The aim of the present study was to establish a suitable culture system for tissue explants from the mantle of the green mussel, Perna viridis. The experiments were conducted using healthy, live green mussels in the size range of 75 to 110 g collected from Pulicat Lake, Tamil Nadu. Three different culture media namely M199, Leibovitz L-15 and sterile seawater were used to assess the most suitable medium for growth, proliferation and viability of mantle epithelial cells. The effect of the addition of two supplements viz., 10% foetal calf serum (FCS) and 0.1% yeast extract to the culture media was also evaluated. After carefully isolating the pallial layer from the mantle tissue, 1-2 mm2 size explants were successfully cultured in 12-well plates at 25°C for up to 14 days. Cultures were monitored under light and phase contrast objectives in an inverted microscope. Cell counts were made and cell size was measured for each treatment. Cells were observed to migrate from the periphery of the explant within 24 h after initiation of cultures. The liberated cells were mostly round and were either granulocytes or hyalinocytes. Fibroblast-like cells were also observed. Our results showed that proliferation of epithelial cells from mantle tissue was maximum in seawater medium (7.4x104 cells ml-1), followed by L-15 medium (2.55x104 cells ml-1). Average cell size in seawater medium was 10.72 μm and that in L-15 and M199 media was 8.56 and 6.39 μm, respectively. Adherent cells were also more prominent and higher in number in seawater medium. Supplementation of culture media with 10% FCS and 0.1% yeast extract improved both cell proliferation and cell size in all the three culture media. Four concentrations of 0.1% yeast extract (@ 50 μl, 75 μl, 100 μl, 150 μl ml-1 medium) were tested in the present study and best results were obtained with 100 μl ml-1, with respect to both cell counts and size