World Aquaculture - June 2023

WWW.WAS.ORG • WORLD AQUACULTURE • JUNE 2023 41 include vitamins and minerals (macro-minerals and micro or trace minerals) that the human body must obtain from outside sources. They may be components of enzymes (cofactors) or act as coenzymes in many biochemical reactions and metabolic processes for growth, survival and reproduction. Micronutrients (i.e., iron, calcium, zinc, iodine, phosphorus, selenium, fluorine and cobalt) are highly bioavailable in SIFFS, meaning that they are easily absorbed by the human body. Fish contains substantial amounts of iron as a component of hemoglobin in red blood cells that transport oxygen to the entire body. Zinc combined with proteins activates enzymes for metabolism and also promotes immunity. Selenium, as a component of some enzymes, protects the body against damage from oxidation and helps develop immunity against cancer. Vitamins, particularly vitamins A, B, C, D, E and K are available abundantly in SIFFS. Mourala Amblypharyngodon mola (Fig.1) contains 2680 µg of vitamin A, as much as 50 times more than that of other fish species and is thus useful in the diet for normal vision, eye health, cell growth, immune function, reproduction and fetal development (Figs. 2-4). Vitamin B12 is essential for the development of myelination, function of the central nervous system, formation of healthy red blood cell and synthesis of DNA and RNA. Vitamin B9, otherwise known as folate, is important in the formation and function of red blood cells, and is crucial to reduce the risk of birth defects of the brain and spine during early pregnancy. Vitamin D facilitates absorption and metabolism of calcium, regulates calcium and phosphorus levels for bone growth and is useful as a curative of osteoporosis, cancer, cardiovascular ailments, diabetes and cognitive and mood disorders (Figs. 5 and 6). Vitamin D3 produced by some SIFFS is an important health supportive. Vitamin E is needed as an antioxidant defense system and vitamin K for blood clotting. Pregnant women who eat fish once weekly during their pregnancy have 3.6 times less risk of low birth weight and premature birth than those who do not eat fish. Consumption of whole fish has immense health benefits as intake of fish bones is a significant source of calcium phosphate for healthy bone Recently, the importance of small indigenous freshwater fish species (SIFFS) in fisheries and aquaculture has come to be recognized because of their rich micronutrient resources. Usually SIFFS are defined as fish species that reach 25 cm in length at maturity. Irrespective of definition, SIFFS comprise fish species that are usually small, distinct from larger ones, and consumed whole. The contributions of these fish species in improving the nutritional security of common people seems incredible. Furthermore, the maintenance of biodiversity, ecosystem balance, employment generation and uplift of the rural economy through provision of livelihoods are some of the benefits harnessed with SIFFS. These small fishes — often considered as weed fish, trash fish, miscellaneous fish, poor people’s fish or incidental catch — were seen to be no longer needed upon the advent of carp culture. Of 450 freshwater SIFFS in India, only 104 species are used directly by humans, including 62 foodfish and 42 ornamental fish (Sarkar and Lakra 2010). Rivers, streams, lakes, canals, reservoirs, wetlands, floodplains, swamps, ponds, tanks, ditches and paddy fields are the home where they breed and nurture progeny to maturity. Alarmingly, SIFFS have disappeared because of habitat destruction, aquatic pollution, injudicious exploitation and aggressive carp culture, resulting in their scarcity, high market demand and price. This article highlights the nutritional value of SIFFS with respect to human health and mentions a strategic plan of their breeding, culture and propagation essential for conservation. Nutritional Value of SIFFS and Their Role in Human Health Fish is of immense nutritional value as a source of protein, fat and a variety of micronutrients (Table 1). The protein content of SIFFS varies between 14-22 percent of fresh weight. Compared to other sources of animal protein, the availability of SIFFS is greater, affordability is cheaper and the unit cost of production lower. The lipid content varies between 0.5-7 percent of fresh weight. Thus, consumption can reduce the risk of cardiovascular disease when SIFFS contain ω-3 polyunsaturated fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Micronutrients are the essential dietary elements needed in very small quantities to combat so-called hidden hunger. These Strategies for Conservation and Promotion of Small Indigenous Freshwater Fish Species D.N. Chattopadhyay and R.N. Mandal FIGURE 1. A pair of Amblypharyngodon mola. (CONTINUED ON PAGE 44)