Seaweed farming for income generation and empowerment of coastal rural community

Seaweeds are macroalgae which are found attached to substratum in benthic habitats. They are multicellular autotrophic photosynthetic plants contributing significantly to the primary production of the marine ecosystem. They are non-flowering plants without true roots, stems, leaves and attached to substratum by means of holdfast. They are a significant feature of most shorelines and shallow water environments throughout the world (Robin South, 1993). They can be found mainly in intertidal and in the sub-tidal region up to a depth, where 0.01 % photosynthetic light is available (Domettila et al., 2013). They have an ecological role of providing habitat and substrata for invertebrates, fish, mammals, and birds (Vásquez 1992; Graham et al., 2007) and a source of food for many grazing vertebrates and invertebrates

Case study on the crop rotation in a disease hit coastal tide-fed shrimp pond with silver pompano, trachinotus blochii (lacepede, 1801)

Hatchery produced silver pompano, Trachinotus blochii were cultured in a typical tide fed coastal pond of 1 ha area, semi-intensive culture of tiger shrimp Penaeus monodonwas practiced for many years. Owing to two consecutive collapse of shrimp culture due to white spot disease, a crop rotation in the same pond with culture of hatchery produced T. blochii was performed sequentially after harvest of diseased hit P. monodon stock. Nursery rearing of hatchery produced T. blochii carried out in hapa in same pond resulted in a survival of 99.91 %. Growth performance of T. blochii and the water quality parameters were monitored monthly over a period of 5 months. Feeding was done with artificial floating pellet feeds with a protein of 45% @ 5-7 % of the body weight twice a day. The fishes reached an average weight of 248.30 ± 0.28 g and average length of 22.82 ± 0.90 cm from 9.65 ± 0.59 g and 5.20 ± 0.24 cm respectively upon harvest after 150 days with a survival of 90%.The absolute growth rate and specific growth rate obtained in the present study was 1.6 g day-1 and 2.2 % day-1 respectively. The results of the study revealed that T.blochii is an ideal species for culture in the low salinity traditional coastal tide fed ponds of Kerala. The study also demonstrates the advantage of crop rotation with fish than continuous culture of shrimp in the shrimp culture ponds and the suitability of culturing. T.blochii in polyculture with fish and shrimps

Training Manual on Live Feed Culture

Live feed refers to small, microscopic living organisms which are used to feed fish larvae especially during the early larval stages. Live food organisms include all plants (phytoplankton) and animal (zooplankton) lives grazed upon by economically important fishes. Phytoplankton are generally eaten by zooplankton and forms the basis of the food chain. Live foods can swim in water column and are constantly available to fish and shellfish larvae and are likely to stimulate larval feeding response. Most of the fish and shellfish larvae in nature feed on small phytoplanktonic and zooplanktonic organisms. The success in the hatchery production of fish fingerlings for stocking in the grow-out production system is largely dependent on the availability of suitable live food for feeding fish larvae, fry and fingerlings. Live food organisms contain all the nutrients such as essential proteins, lipids, carbohydrates, vitamins, minerals, amino acids and fatty acids and hence are commonly known as “living capsules of nutrition”

Training Manual on Hatchery production and farming of marine finfishes

Training Manual on Hatchery production and farming of marine finishe

Cobia culture in low volume cages in coastal waters of Uttara Kannada, Karnataka

Cobia, Rachycentron canadum is a marine finfish globally favoured for aquaculture. In India, cage culture of cobia was first reported by ICAR-CMFRI in 2013 with better growth rate recorded under conditions of higher salinities (Philipose et al.2013). The present report is on the growth and production of cobia, Rachycentron canadum in Gangavali estuary (14o 61’ 225’’ N and 74 o35’726’’E) of coastal Karnataka during the period 2018-19

Stunted fingerling production ensures continuous supply of good quality seed for marine finfish farming

Application of compensatory growth pattern in finfishes for enhancing aquaculture production is an innovative method adopted by several farmers in freshwater farming systems. Stocking of stunted fishes have the primary advantages such as growth compensation, suitability for short duration farming, economic usage of feed, extended period of good quality seed availability and enhanced survival rate with better yield. An attempt has been initiated to adopt the principles of compensatory growth pattern in marine aquaculture systems and the possible interventions in these aspects is discussed. Preliminary results reveal that marine finfishes such as Snubnose pompano and Mangrove red snapper exhibits compensatory growth pattern during post- stunting rearing period in both marine and low saline condition

Training manual on Open sea cage culture

Training manual on Open sea cage cultur

Brief note on infestation of Diplectanum sp. in Asian seabass

Recently open sea cage farming has emerged as an alternative and additional income source for fishermen and fish farmers in India. Asian seabass, Lates calcarifer is widely used in open sea cage culture due to its high market demand. In cage farming, high stocking densities and poor water quality enhance the parasite loads of the cultured fishes. In this study, 47 specimens of Asian seabass collected from cages located in Naganathwada, Sunkeri, Ankola were analysed with the aim of identifying the parasites prevalent among this species. All external and internal organs of each fish were examined separately under microscope for parasites. The collected monogenean parasites were washed in a 0.85% saline solution and fixed in 70% ethanol and identified. Most of the infected fishes had dark coloration of the body and postmortem findings revealed gills with excessive mucus secretion and sticking of the gill tips with greyish coloration

Argulus quadristriatus infestation in cage cultured Asian seabass

In Indian waters, genus Netuma is represented by two species namely N. bilineata and N. thalassina (Order: Siluriformes, Family: Ariidae). Rounded shout, thin lips, inconspicuous median longitudinal groove, and higher anal fin ray count (16-19) are characters of N. bilineata while N. thalassina has conical snout, clearly visible median longitudinal groove and lower anal fin ray count (13-15). Prior to the erection of N. bilineata (earlier considered as synonym of N. thalassina) as valid species, Indian workers had difference of opinion regarding the representation of species under this genus from Indian waters

Artemia

Artemia, brine shrimp constitute the most widely live diets used in the larviculture of fish and shellfish because of the availability of dry cysts and the practical convenience of hatching. The total length is about 8-10mm for adult males and 10-12mm for females, the width including legs is about 4mm for both sexes