Extra-Fortification of Zinc Upsets Vitellogenin Gene Expression and Antioxidant Status in Female of Clarias magur brooders.

The present experiment was designed to evaluate the effect of graded level of zinc on Vitellogenin gene (Vtg) expression and antioxidant enzymes in threatened catfish, Clarias magur (C. magur). One hundred and eighty female C. magur with an average weight of 145 ± 5 g were allocated in twelve cemented tanks with dimension 4.5 × 2 × 1 m for a period of 60 days. Fish were distributed in four groups with three replicates following the completely randomised design. The first group treated as control (C) fed with basal diet contained normal zinc level, and remaining groups were fed with basal diets having 50, 200 and 300 mg/kg zinc acetate and treated as T1, T2 and T3 respectively. To evaluate the effect of dietary zinc supplementation on Vtg gene expression, three sampling were carried out, I sampling (April, before starting the experimental trail), II sampling (May, after 1 month of feeding trail) and III sampling (June before breeding season). In the present study, a dose-dependent relationship between Vtg gene expression and zinc inclusion in the diet of threatened catfish, C. magur, was reported. Vtg gene expression increased in all groups from I sampling to II sampling but the highest Vtg gene expression was found in T1 group and the lowest in T3 group at II sampling. Vtg gene expression among the treatments differs significantly (P < 0.05) in each sampling. Accumulation of zinc was measured by Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) in C. magur and it was reported that the significantly higher (P < 0.05) zinc was accumulated in the liver and ovary of T3 group as compared to other groups. The antioxidant enzyme activities (superoxide dismutase, SOD, catalase and GST) were also measured in different tissues (liver, gill and ovary) to evaluate the effect of extra-supplementation of zinc on the antioxidant status. In T3 group, SOD, catalase and GST activities were significantly higher than those in other groups. In the current study, serum glucose level was also measured and it was found in increasing trend with inclusion of zinc in the diet of C. magur. In the present study, it can be concluded that the zinc exhibits beneficial effect only up to 50 mg/kg. Thus, it is concluded that supplementation of zinc at 200 mg/kg or more disrupts Vtg gene expression and antioxidant status.

Effect of Dietary Lipid Level on Growth Performance, Body Composition, and Physiometabolic Responses of Genetically Improved Farmed Tilapia (GIFT) Juveniles Reared in Inland Ground Saline Water.

A 60-day feeding trial was carried out to determine the effect of dietary lipid levels on growth and physiometabolic responses to optimize the dietary lipid requirement for maximizing the growth of Genetically Improved FarmedTilapia (GIFT) juveniles reared in inland ground saline water (IGSW) of medium salinity (15 ppt). Formulation and preparation of seven heterocaloric (389.56-449.02 Kcal digestible energy/100 g), heterolipidic (40-160 g/kg), and isonitrogenous (410 g/kg crude protein) purified diets were done for conducting the feeding trial. Random distribution of 315 acclimatized fish (mean weight 1.90 ± 0.01 g) was made in seven experimental groups such as CL4 (40 g/kg lipid), CL6 (60 g/kg lipid), CL8 (80 g/kg lipid), CL10 (100 g/kg lipid), CL12 (120 g/kg lipid), CP14 (140 g/kg lipid), and CL16 (160 g/kg lipid) with 15 fish per triplicate tank (fish density, 0.21 kg/m3). Respective diets were used for feeding the fish at satiation level three times daily. Results indicated that weight gain percentage (WG%), specific growth rate (SGR), protein efficiency ratio, and protease activity significantly increased up to 100 g lipid/kg fed group, and then the values significantly decreased. Muscle ribonucleic acid (RNA) content and lipase activity were highest in 120 g/kg lipid-fed group. RNA/DNA (deoxyribonucleic acid) and serum high-density lipoproteins levels of 100 g/kg lipid-fed group were significantly higher than 140, and 160 g/kg lipid-fed groups. The lowest feed conversion ratio was found in the 100 g/kg lipid-fed group. The amylase activity was significantly higher in 40 and 60 g lipid/kg fed groups. The whole-body lipid level was increased with increasing the dietary lipid levels, whereas, there was no significant difference in whole-body moisture, crude protein, and crude ash contents of all groups. Highest serum glucose, total protein and albumin, and albumin to globulin ratio and lowest low-density lipoproteins level were found in 140 and 160 g/kg lipid-fed groups. Serum osmolality and osmoregulatory capacity did not vary significantly, whereas carnitine palmitoyltransferase-I and glucose-6-phosphate dehydrogenase showed an increased and decreased trend, respectively, with the increasing dietary lipid levels. According to second-order polynomial regression analysis based on WG% and SGR, the optimum dietary lipid for GIFT juveniles in IGSW of 15 ppt salinity was found to be 99.1 and 100.1 g/kg, respectively.

Nonylphenol exposure in Labeo rohita (Ham.): Evaluation of behavioural response, histological, haematological and enzymatic alterations.

The impact of acute and chronic exposure of nonylphenol (NP) on behaviour, histopathology, haematology and biochemical parameters of Labeo rohita (Hamilton, 1822) was investigated in the current study. The 96 h LC50 of NP for L. rohita was estimated to be 0.548 mg L-1. Acute toxicity of NP induced several behavioural alternations. Further, sub-lethal NP exposure for a period of sixty days to 1/10th (0.0548 mg L-1), 1/15th (0.0365 mg L-1) and 1/20th (0.0274 mg L-1) of 96 h LC50 resulted a reduction in total erythrocyte count and haemoglobin content whereas the total leukocyte count was observed to increase significantly. Among the biochemical parameters, blood glucose level increased, but there was significant decrease in total serum protein, albumin and globulin level. Significant alterations occurred in the histological architecture of gill tissue in NP exposed groups. The catalase and superoxide dismutase activity in gill tissues were elevated significantly while the concentration dependent inhibition of acetylcholinesterase activity was observed on 20th, 40th and 60th day of NP exposure. An increased glutathione-S-transferase activity in gill tissue was also observed in NP exposed groups. The present ecotoxicological study provides a reliable indication for the obligation to control the use and safe disposal of NP.

Towards Porous Silicon Oxycarbide Materials: Effects of Solvents on Microstructural Features of Poly(methylhydrosiloxane)/Divynilbenzene Aerogels.

We investigate the impact of solvents on the microstructure of poly(methylhydrosiloxane)/divinylbenzene (PMHS/DVB) aerogels. The gels are obtained in highly diluted conditions via hydrosilylation reaction of PMHS bearing Si-H groups and cross-linking it with C=C groups of DVB. Polymer aerogels are obtained after solvent exchange with liquid CO2 and subsequent supercritical drying. Samples are characterized using microscopy and porosimetry. Common pore-formation concepts do not provide a solid rationale for the observed data. We postulate that solubility and swelling of the cross-linked polymer in various solvents are major factors governing pore formation of these PMHS/DVB polymer aerogels.

Regenerable, innovative porous silicon-based polymer-derived ceramics for removal of methylene blue and rhodamine B from textile and environmental waters.

The presence of residual color in treated textile wastewater above the regulation limits is still a critical issue in many textile districts. Innovative, polymer-derived ceramics of the Si-C-O system were here synthesized in order to obtain porous nanocomposite materials where a free carbon phase is dispersed into a silicon carbide/silicon oxycarbide network. The sorbents were comprehensively characterized for the removal of two model water-soluble dyes (i.e., the cation methylene blue and the zwitterion rhodamine B). Adsorption is very rapid and controlled by intra-particle and/or film diffusion, depending on dye concentration. Among the nanocomposites studied, the SiOC aerogel (total capacity about 45 mg/g, is easily regenerated under mild treatment (250 °C, 2 h). Adsorption of dyes is not affected by the matrix composition: removals of 150 mg/L methylene blue from river water and simulated textile wastewater with high content of metal ions (2-50 mg/L) and chemical oxygen demand (800 mg/L) were higher than 92% and quantitative for a dye concentration of 1 mg/L.