Transgene expressions in seabass (Lates calcarifer) following muscular injection of plasmid DNA: a strategy for vaccine development?

Muscular injection has become one of the direct methods for transferring foreign DNA into organisms. The technique has been recently introduced in the development of vaccines and gene therapy. Vaccine development, in particular, would be desirable in managing viral diseases in farmed fish. In this study, the technique was performed on seabass (Lates calcarifer) and was found that the foreign gene could be transferred successfully through injection into the muscles.

Biogeographic characterization of fish communities and associated benthic habitats within the Flower Garden Banks National Marine Sanctuary: sampling design and implementation of scuba surveys on the coral caps

The Flower Garden Banks National Marine Sanctuary (FGBNMS) is located in the northwestern Gulf of Mexico approximately 180 km south of Galveston, Texas. The sanctuary’s distance from shore combined with its depth (the coral caps reach to within approximately 17 m of the surface) result in limited exposure of this coral reef ecosystem to natural and human-induced impacts compared to other coral reefs of the western Atlantic. In spite of this, the sanctuary still confronts serious impacts including hurricanes events, recent outbreaks of coral disease, an increase in the frequency of coral bleaching and the massive Diadema antillarum die-off during the mid-1980s. Anthropogenic impacts include large vessel anchoring, commercial and recreational fishing, recreational scuba diving, and oil and gas related activities. The FGBNMS was designated in 1992 to help protect against some of these impacts. Basic monitoring and research efforts have been conducted on the banks since the 1970s. Early on, these efforts focused primarily on describing the benthic communities (corals, sponges) and providing qualitative characterizations of the fish community. Subsequently, more quantitative work has been conducted; however, it has been limited in spatial scope. To complement these efforts, the current study addresses the following two goals put forth by sanctuary management: 1) to develop a sampling design for monitoring benthic fish communities across the coral caps; and 2) to obtain a spatial and quantitative characterization of those communities and their associated habitats.

Liver genomic responses to ciguatoxin: evidence for activation of Phase I and Phase II detoxification pathways following an acute hypothermic response in mice

Ciguatoxins (CTX) are polyether neurotoxins that target voltage-gated sodium channels and are responsible for ciguatera, the most common fish-borne food poisoning in humans. This study characterizes the global transcriptional response of mouse liver to a symptomatic dose (0.26 ng/g) of the highly potent Pacific ciguatoxin-1 (P-CTX-1). At 1 h post-exposure 2.4% of features on a 44K whole genome array were differentially expressed (p ≤ 0.0001), increasing to 5.2% at 4 h and decreasing to 1.4% by 24 h post-CTX exposure. Data were filtered (|fold change| ≥ 1.5 and p ≤ 0.0001 in at least one time point) and a trend set of 1550 genes were used for further analysis. Early gene expression was likely influenced prominently by an acute 4°C decline in core body temperature by 1 h, which resolved by 8 h following exposure. An initial downregulation of 32 different solute carriers, many involved in sodium transport, was observed. Differential gene expression in pathways involving eicosanoid biosynthesis and cholesterol homeostasis was also noted. Cytochrome P450s (Cyps) were of particular interest due to their role in xenobiotic metabolism. Twenty-seven genes, mostly members of Cyp2 and Cyp4 families, showed significant changes in expression. Many Cyps underwent an initial downregulation at 1 h but were quickly and strongly upregulated at 4 and 24 h post-exposure. In addition to Cyps, increases in several glutathione S-transferases were observed, an indication that both phase I and phase II metabolic reactions are involved in the hepatic response to CTX in mice.

Haematological and biochemical alterations of Catla catla fingerlings following sublethal exposure to Nuvan

The sublethal exposure (0.24 ppm) of Nuvan on some biochemical compositions such as serum protein, blood glucose, glutamate oxaloacetate transaminase (AST) and glutamate pyruvate transaminase (ALT) and on some hematological parameters such as red blood corpuscles (RBC), white blood corpuscles (WBC), hemoglobin content (Hb), mean corpuscular concentration (MCV), mean corpuscular hemoglobin concentration (MCHC) of Catla catla fingerlings were studied. The hematological and biochemical parameters evoked a significant reduction (excepting MCV, ALT and AST which is significantly increased) with increasing days of Nuvan exposure.

Recovery, growth and carcass composition following periods of restricted ration and full feeding in indian major carp, Rohu (Labeo rohita H.)

A 90-day experiment was conducted to determine the effect of restricted ration and full feeding on the recovery growth and carcass compositions of fingerlings (average weight - 20.74 ± 0.13 g) of rohu, Labeo rohita (H.). Rohu fingerlings procured from a local fish breeder were fed with commercial pelleted feed (27% crude protein) during the two-week acclimatization in the laboratory condition. Experimental pelleted diet (30% crude protein) was prepared and the control group (T sub(CFR)) was fed at 3% of body weight for the 90-day trial period. The experimental group T sub(1FR) was fed for three days at 1% of body weight and the next three days at 3% of body weight, T sub(2FR) was fed for seven days at 1% of body weight and the next seven days at 3% of body weight, T sub(3FR) was fed for 15 days at l% of body weight and the 15 days at 3% of body weight and T sub(4FR) was fed for 25 days at 1% of body weight and the next 25 days at 3% of body weight, alternating between 1 and 3% for the specified period during the 90-day trial period. Daily rations were divided into two equal meals per day at 09.00 and 16.00 hours. Average percent survival rate of rohu during the 90-day trial period was more than 90. Percent live weight gain (98.90 ± 0.34, 113.0 ± 5.93, 125.71 ± 11.01 and 141.90 ± 2.89), specific growth rate (1.53 ± 0.01 1.68 ± 0.06, 1.80 ± 0.10 and 1.96 ± 0.02%/d) and absolute growth rate (1.33 ± 0.13, 1.38 ± 0.07, 1.39 ± 0.04 and 1.44 ± 0.07g/d) of the experimental groups (T sub(1FR), T sub(2FR), T sub(3FR) and T sub(4FR) respectively) increased with the advancement of the experiment in comparison to those in control, T sub(CFR) (90.92 ± 5.81%, 1.44 ± 0.07%/d and 1.34 ± 0.20g/d, respectively) and were proportionately correlated with the degree of deprivation probably through the mechanism of increased feed intake (hyperphagia), feed efficiency ratio or gross growth efficiency, protein efficiency ratio and the superior feed conversion ratio reflecting in better performance index. The body length and muscle composition of fish indicated that recovery growth happened due to protein growth but certainly not due to fat deposition in the gut. Feeding at 1 and 3% of body weight alternating over a period of 25 days might economize the culture operation of rohu.

Investigations on long distance transportation of fish. 3. Field trials with a dismantlable insulated galvanised iron container

The paper communicates the results of field trials conducted with a dismantlable insulated galvanised iron container designed and fabricated by the first two authors in their laboratory. Different varieties of fishes and different types of packing, namely, fresh iced, chilled iced and frozen were employed in the transportation experiments which were conducted from Kakinada to Howrah, Kakinada to New Delhi and Paradeep to Howrah. In all the experiments the container performed exceedingly well and has still remained in very trim condition.

Investigations on long distance transportation of fish. 4. A comparative study of the performance of expanded polystyrene slabs and multi-layer gunny (jute) fabric as insulants

A comparative study of the insulation efficiencies of expanded polystyrene slabs and multi-layer gunny fabric in long distance transportation of fresh iced fish was made. Used plywood boxes (second hand tea chests) were employed as containers and the experiments conducted between Kakinada and Calcutta. All the three insulants tried, namely, 25.4 mm thick expanded polystyrene slab, four and two layer gunny (jute) fabric, all sealed in 150 gauge polythene sheets, showed comparable insulation efficiencies, considering total bacterial counts, organoleptic qualities and TMA and TVN values of the transported fish as parameters.

Investigations on long distance transportation of fish. 5. Transportation of filleted and round seer fish (Scomberomorus sp.) from Kakinada to Calcutta by rail

Iced seer fish (Scomberomorus sp.) was transported by rail in expanded polystyrene insulated plywood boxes from Kakinada to Calcutta in round and fillet forms. While both withstood the rigors of transportation squarely, the fillets fetched only half the price of round fish in the auction conducted at the Calcutta market.

Transportation of fish - 1. A preliminary study on insulated containers and their efficacy in long distance transportation

Polythene lined thermocole insulated plywood boxes (second-hand tea chests) could be successfully used for transport of fresh iced fish. It was found that a minimum of 25 mm thermocole insulation was necessary during summer (April to June) and 15 mm during winter (Nov. to March). By using these insulated boxes the initial fish to ice ratio could be brought down to 1:0.75 and still further to 1:0.5 at the height of winter in Jan. and Feb. These second-hand tea chests are robust and are able to stand a minimum of 5 trips to and fro. The moulded polystyrene boxes are not suited for long distance transport. Another redeeming feature in the entire operation was that there was practically no loss of fish due to spoilage in transit. 100% of the fish transported was in acceptable condition and could be marketed. In the non-insulated boxes used by the trade, the loss due to spoilage ranged from 10% to 25%, and this could be completely eliminated by the use of these insulated boxes.

Investigations on long distance transportation of fish 1. Transportation of frozen fish from Cochin to Calcutta

Oil Sardine (Sardinella longiceps), mackerel (Rastrelliger kanagurta), cat fish (Arius sp.), threadfin bream (Nemipterus japonicus) and ribbon fish (Trichurus sp.) were frozen in glazed/unglazed blocks, packed in expanded polystyrene (EPS) insulated plywood boxes with and without additional ice and despatched in uninsulated parcel vans of trains from Cochin to Calcutta. The consignments reached the destination in excellent condition and were readily disposed off.

Change in quality of different variety of fish during long distance transportation

A study was conducted to investigate the quality of iced fish of different species during long distance transportation. Total bacterial counts showed different species to show different quality deterioration under similar handling conditions.