Integrated culture of farmed fish with mollusc and seaweeds will not only help maintain the environment but also make aquaculture profitable.
The noteworthy impact of the pandemic is the scintillation of awareness about our own health and wellbeing in each and every ones mind. Many of us have fallen head over heels for every methodology that boost our immunity and maintains fitness. Clams are not low with their positive impacts on human kind. The lucrative utility of clams can be dealt with nutritional, commercial and ecological aspect to the mankind, basically “clam” serves as an umbrella term for several kind of bivalve molluscs, which include oyster, scallops and molluscs.
India is one among the greatly growing countries that puts in immense work on pearl culture systems in certain parts of the nation. There are farmers earning 12 lakhs per harvest with no use of high technologies and inventions. Certain institutes around the country play major roles in training small scale farmers to produce clams for meat as well as pearls, which remains as a backbone in creating self-reliant India.
Growing population and industrialization leads to disposition of harmful pollutants in our water bodies. The biofiltration aspect found in clams can lead to much simpler and cheaper ways to clear our environment. The worldly goods processed by indigenous clams are boundless and the researches under this field is growing in intermediate pace.
Clams is a raising food trend worldwide mainly because of education among people about its nutritional availabilities. These high protein (13 to18%), low calorie (45cal,in 6 scallops),low fat(>3%)substance can be said as a powerhouse of nutrients since it is rich in minerals like zinc,selenium,iron,magnesium and Bvitamins likeniacin.The presence of some free amino acids, such as threonine, glycine, alanine, glutamic acid, aspartic acid provides these with rich meaty and sweety flavour, which is devoured by majority of the people. Several clam varieties have been used in ethnomedicines like siddha, traditional Chinese medicines and African medicines to have anti-inflammatory properties and immunomodulatory or simply wound healing and anti-cancer and steroidogenic activity, due to substances like 6-bromoindirubin,3-methoxime, 6-bromoisatin, Acetic Acid, Allantoin present in them. Species of marine muricidae family are traditionally used in India and other countries, some species like, Chicoreus ramosus, Chicoreus virgineus, Dicathaisorbita, Murexpecten. So regular consumption of clams or biofortification of food substances with derivatives from clam varieties can fight malnutrition not only in India but in a global scale.
According to FAO 2019, the world has produces 17,511 thousand metric tonnes of molluscs in the year 2018 to 2019.India has earned 238 USD by exporting mollusc meat to countries like USA,UK,Italy and China.
Pearls uncommonly called as queen of jewels has been a symbol of richness over ages. Lamellidens marginalis, Corrianus, Parrysia corunguta are the species cultured for pearl in India. Analysis of FAO global statistics shows that in the past decade (from 2005 to 2014), the average annual output of Chinese pearls was 3540 tonnes (t) valued at 15 million USD. This output accounted for over 98% of global cultured pearl output, of which freshwater pearls accounted for 99.5%. Japan has been the world’s major marine pearl producer for over a century, and has developed advanced technology in pearl oyster culture and pearl production. In the past decade, the average annual value of marine cultured pearl production in Japan was 127 million USD, accounting for 51.6% of global pearl output value. Average annual production of marine cultured pearls was 23 t in Japan, 18.6 t in China and 12.9 t in French Polynesia.
India is one among the growing countries in pearl production, in context of the rich coastal line and species availability mollusc culture can be considered as one with highest potential in the country. In many tribal regions molluscs are consumed and the discarded parts like shells are a way to economy through cottage industry.
Ecological benefits Bivalve species pocess strong innate immunity both cellular and humoral system with several variety of sensitive receptors, selective effectors, and synergistic genetic regulatory networks that afford protection in a fluctuating environment. The filter feeding ability though leads to death of juveniles due to bacterial commensalism, in absence of such intruding factors works excellently as biofilters thereby absorbing most of the contaminants present in littoral waters.
The aquaculture industry faces many disease-causing pathogens which are transmitted mainly through waters and resulting in loss of catch, and also consumers worldwide never prefer antibiotic concentration in fish flesh that was used to eradicate disease in culture system. Biofiltration ability of many mollusc varieties absorbs antibiotics and certain neurotoxins such as saxitoxins released from dinoflagellates like Alexandrium species.
It is found that integrated culture of farmed fish with mollusc and seaweeds potentially reduces contamination even from nitrogenous wastes from the fishes, thereby producing hugely profitable yet healthier varieties of food fishes for the farmers.
(Eupho CJ is student in Fisheries College and Research Institute, Thoothukudi, Tamil Nadu. Views expressed are personal.)