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As low saline inland shrimp culture is becoming more prevalent day by day, the application of mineral supplements in pond water has become a necessity to maintain the ionic concentration by fortifying the deficiency of key minerals like calcium (Ca), magnesium (Mg) and potassium (K). In this study, a 120-day trial was conducted in earthen ponds, wherein, the benefits of applying mineral supplement in low saline (>5 Practical Salinity Unit, PSU) was evaluated by measuring the animal performance parameters like feed conversion ratio (FCR), specific growth rate (SGR), survival rate, weight gain, mineral composition of experimental animals and the quality of rearing water like pH, dissolved oxygen (DO), salinity, hardness, alkalinity, biological oxygen demand (BOD), chemical oxygen demand (COD), Vibrio count and phytoplankton population in comparison with control. Our study showed that the application of mineral mixture improved the animal performance in terms of FCR, SGR and body weight. Despite, on supplementation, an increased mineral (Ca, Mg and K) content and improved phytoplankton levels was observed in rearing water whilst corresponding increase in minerals Ca, Mg and K was observed in animals as well. Indicating the improvement in water quality, mineral composition in water and animals and growth performance, affirming good absorption of minerals by animals.

The present study was carried out to examine the specific digestive enzyme activity of Nile tilapia (Oreochrmis niloticus) fingerlings, fed with different percentages of Guar sprout meal (GSM). The experiment was set with five isonitroneous and isolipidic diets as T1, T2, T3, T4 and T5 containing guar sprout meal at an inclusion rate of 0, 25, 50, 75 and 100%, respectively. The result showed a higher protease activity in the fish nourished with 0%, 25% and 50%. GSM beyond 50% showed poor protease activities especially in all parts of the gut (gastrointestinal tract). There was significant acceleration in amylase and lipase activities in the digestive tract (liver, stomach and intestine) with increased GSM levels. The results accomplish that 25-50% inclusion of GSM can be a favorable and economically sustainable protein source in the diet of Nile tilapia fingerlings.

Mud crab farms along the east coast of India have been facing mysterious mass mortality for the past few years. Recently, Mud crab reovirus was found to be responsible for this mortality in the east coast of India. This study investigated the mortality rate of mud crabs raised in an open-pen and cage environment in relation to mud crab reovirus infection. The crabs were cultured in open pens, cages within the pens, and cages outside the pens i-e in open water without any enclosures. The dead and moribund crabs were tested for etiological agents responsible for the mortality using histopathology, TEM and RTPCR. The mortality rate in the open pen culture system was found to be 73 ± 4.57%, whereas the mortality rate in cages inside the pen was found to be 18 ± 2.21%, and in cages outside the pen in open water was found to be 17.3%. Mud crab cannibalistic behavior was found to be the primary rationale for the higher MCRV transmission rate in open pens where the crabs are not separated, contrary to the cage culture technique. The present study revealed that rearing mud crabs in cage crabs in individual cages decreases the mortality rate of mud crabs up to 20 percent. Therefore, fattening or culturing mud crabs in cages benefits farmers with higher survival rates and economic performance.

Conservation of the mangrove habitat is highly essential to protect the coastal regions and the livelihood of the local folk, mainly comprising fishermen community. Involvement of local inhabitants is the key factor for the success of all ecosystem conservation activities. In the present study, the attitude and perceptions of local people of Puduveypu area of Ernakulam District, Kerala towards the conservation of Mangrove ecosystem were examined. A total of 1966 respondents were surveyed. Among these, 52.3% of the villagers were positive and showed interests in the ecological importance of Mangrove ecosystems. A small group of people viewed that mangroves restrict their developmental activities and consider them as a menace. The study illustrates that it is important to inculcate a mangrove friendly lifestyle among these communities for better conservation of this ecosystem.

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Mud crab culture/ fattening is a lucrative business with high profit margin since they have high economic and export value. Compared to shrimp culture, crab fattening has many advantages such as short production cycle, high tolerance to water quality, rapid growth rates in captivity etc. Currently there is a non‐availability of cheap commercial feed for crabs so that raw feeds such as low value fishes have been used for rearing mud crabs. The current study is done to determine the growth performance of Scylla serrata (Forskal, 1775) fed with different processed wet feeds. The crabs weighing 250‐300g were stocked in individual cages and experiment is conducted with three different feed treatments including processed chicken intestine, processed shrimp head waste, oyster meat and control feed is processed small sized low value fish. Of all the feeds, mud crabs which were fed with chicken intestine showed better performance followed by oyster meat, shrimp head waste and low value fish. The present study concludes that fattening mud crabs with chicken intestine as feed showed better growth and economic performance.