K. V. Dhaneesh

Metals in Fish along the Southeast Coast of India

Metal concentrations (cadmium, chromium, iron, lead, copper, manganese, zinc and mercury) in the muscle of five fish species (Epinephelus chlorostigma, Lutjanus russelli, Terapon jarbua, Cynoglossus arel and Lagocephalus lunaris) from the six fish landing centres along southeast coast of India were measured. In Cuddalore and Mudasalodai, the level of toxic metals cadmium, chromium and manganese were well above the permissible limits. Concentrations of cadmium, chromium, manganese and mercury in C. arel were above the permissible limit and it is consistent with their habitat and diet. The results showed a relationship between metal concentrations and pollution status of the areas.

Breeding and mass scale rearing of clownfish Amphiprion percula: feeding and rearing in brackishwater

Breeding and mass scale larval rearing of clownfish Amphiprion percula is very limited in brackishwater. We designed an indoor program of A. percula culture in brackishwater with a salinity of 24±1, during which the impacts of feed type, water temperature, and light intensity, on the efficiency of its reproduction, were revealed. The fish were accommodated along with sea anemones in fibre glass tanks to determine the influence of brooder diet on breeding efficiency. Higher reproductive efficiency [number of eggs laid (276 ± 22.3 eggs)] was observed when fish were fed live Acetes sp. rather than clam (204 ± 16.4 eggs), trash fish (155 ± 12 eggs) and formulated feed (110 ± 10 eggs). The spawning rate was increased during September and October (water temperature, 28.74 ± 0.55°C) on average of 2.4 spawning per month; and low spawning rate was in January (water temperature, 24.55 ± 0.45°C) on average of 1 spawning per month. Among three light intensities (100, 500, and 900 lx) set to evaluate larval survival rate, larvae showed the highest survival rate (65.5%) at 900 lx. The breeding method specifically in brackishwater developed in the present study is a new approach, will help the people from the regions of estuary and backwater to enhance their livelihood and it will lead to reduce the exploitation from the wild habitat.

Nutritional Evaluation of Commercially Important Fish Species of Lakshadweep Archipelago, India

Estimation of nutrition profile of edible fishes is essential and thus a bio-monitoring study was carried out to find out the nutritional composition of commonly available fishes in Agatti Island water of Lakshadweep Sea. Protein, carbohydrate, lipid, ash, vitamin, amino acid and fatty acid composition in the muscle of ten edible fish species were studied. Proximate analysis revealed that the protein, carbohydrate, lipid and ash contents were high in Thunnus albacares (13.69%), Parupeneus bifasciatus (6.12%), Hyporhamphus dussumieri (6.97%) and T. albacares (1.65%), respectively. Major amino acids were lysine, leucine and methionine, registering 2.84–4.56%, 2.67–4.18% and 2.64–3.91%, respectively. Fatty acid compositions ranged from 31.63% to 38.97% saturated (SFA), 21.99–26.30% monounsaturated (MUFAs), 30.32–35.11% polyunsaturated acids (PUFAs) and 2.86–7.79% branched fatty acids of the total fatty acids. The ω-3 and ω-6 PUFAs were ranged 13.05–21.14% and 6.88–9.82% of the total fatty acids, respectively. Hence, the fishes of Lakshadweep Sea are highly recommended for consumption, since these fishes are highly enriched with nutrition. The results can be used as a baseline data for comparing the various nutritional profiles of fishes in future.

Oil extraction from microalgae for live prey enrichment and larviculture of clownfish Amphiprion percula

The present study investigates the potential of algal oil (extracted from Nannochloropsis salina ), cod liver oil, olive oil and yeast for live prey enrichments in A. percula larviculture. After hatching, larvae were divided into six experimental groups as follows. Larvae fed on non-enriched (control), cod liver oil enriched, olive oil enriched, algal oil enriched, yeast enriched live prey and wild collected mixed plankton. Growth (total length, standard length, body depth, head depth and weight), survival, carotenoid and PUFAs content were observed at higher levels in juveniles fed on wild plankton and algal oil enriched diets. Thyroid hormones (T 3 , T 4 and TSH) levels were also higher in the juveniles fed on wild plankton followed by algal oil enriched diet. Based on the present study, it can be concluded that mixed zooplankton and algal oil enriched rotifers Brachionus plicatilis and Artemia nauplii may be considered suitable live prey for clownfish larviculture.

Hatchery Production of Marine Ornamental Fishes: An Alternate Livelihood Option for the Island Community at Lakshadweep

The hobby of marine ornamental fish keeping is more valuable as aquarium keeping has become more popular and more hobbyists are interested in this lucrative trade. The export value of ornamental fishes has increased 10 times higher from 0.9 to 9 million US

Bio-accumulation of metals on reef associated organisms of Lakshadweep Archipelago

and continues to reach almost 29 million US

Breeding, embryonic development and salinity tolerance of Skunk clownfish Amphiprion akallopisos

in 2007 (Tissera, 2010).