Observations on broodstock maintenance, breeding and early larval development of the common spider conch Lambis lambis (Linnaeus, 1758) in captivity

Spider conches are common in shallow waters of the Indian coast. Of the eleven species reported from Indian waters, six species of the genus Lambis are categorised under Schedule IV of the Indian Wildlife Protection Act, 1972. Studies on the breeding of Lambis spp. are limited Considering its importance, an attempt was made to breed the common spider conch Lambis lambis, under controlled conditions. The brooders ranged from 152-184 mm/80-400 g in size/weight. They were maintained on macroalgal diet under static as well as airlift recirculation system. The conch shells, after 4 months of maintenance, exhibited mating behaviour and laid eggs under captivity during October-December 2010. The morphology and development of the embryo within the egg filaments, hatching, embryonic and early larval development up to 35 days post-hatch (dph) is detailed and compared with the similar observation made at Majuro atoll, Marshall Islands

टूटीकोरिन जिले की मोलस्कन संपदाएं

टूटीकोरिन जिले की मोलस्कन संपदाए

Landings of juvenile Uroteuthis (Photololigo) singhalensis in Tuticorin Fishing Harbour

In Tuticorin Fishing Harbour about 200 trawlers operate daily from 5 am to 11 pm for single day fishing. Wooden and steel trawlers in three sizes, namely small boats (OAL 35-40 feet), medium boats (OAL 40-50 feet) and large boats (OAL up to 80 feet) operate from this harbour

On captive breeding, spawning, embryonic and larval development in Horse conch, Pleuroploca trapezium (Linnaeus, 1758) from Southeast coast of India

795-801Captive breeding, spawning and larval development of endangered gastropod, horse conch, Pleuroploca trapezium (Linnaeus, 1758) was studied and reported from Thoothukudi, Southeast coast of India for the first time. Wild collected brooders of P. trapezium were spawned after 10 months of rearing under captivity as a cluster of egg cases on the wall of the tank and also above the shell of the other horse conch. Each egg case had 150 to 460 numbers of eggs. The incubation period ranged from 23 to 30 days and 91 % of hatching was recorded. Detailed observations were made on the embryonic development and larval rearing until 40 days of post hatch (dph). The day one larvae measured 750±14.15 μm and reached an average shell size of 1830±37.48 μm after 40 dph. After 30 dph, though most of the pre-juveniles settled and crawled at the bottom of the rearing tank, the presence of active velum indicated that the competency to metamorphosis for the development of juvenile was not fully attained and complete mortality occurred. Therefore, further study is warranted using different cues to promote the metamorphosis of Pleuroploca trapezium for successful life cycle closing and juvenile production

Observations on the mass mortality of molluscs in Karapad Bay, Thoothukudi

The western bank of the shallow Tuticorin Bay is deeply indented in two places one at Karapad and the other at Uppar. The Karapad Creek is situated 2 km south of Thoothukudi having an area of 0.29 km2. The shore is sandy and silty in nature and harbours variety of molluscan groups apart from other interstitial fauna. The bay area is devoid of any macro algal vegetation

Account of bivalve fishery resources of Southern Tamil Nadu

Account of bivalve fishery resources of Southern Tamil Nad

Captive breeding, spawning, embryonic and larval development in Horse conch, Pleuroploca trapezium (Linnaeus, 1758) from Southeast coast of India

Captive breeding, spawning and larval development of endangered gastropod, horse conch, Pleuroploca trapezium (Linnaeus, 1758) was studied and reported from Thoothukudi, Southeast coast of India for the first time. Wild collected brooders of P. trapezium were spawned after 10 months of rearing under captivity as a cluster of egg cases on the wall of the tank and also above the shell of the other horse conch. Each egg case had 150 to 460 numbers of eggs. The incubation period ranged from 23 to 30 days and 91 % of hatching was recorded. Detailed observations were made on the embryonic development and larval rearing until 40 days of post hatch (dph). The day one larvae measured 750±14.15 μm and reached an average shell size of 1830±37.48 µm after 40 dph. After 30 dph, though most of the pre-juveniles settled and crawled at the bottom of the rearing tank, the presence of active velum indicated that the competency to metamorphosis for the development of juvenile was not fully attained and complete mortality occurred. Therefore, further study is warranted using different cues to promote the metamorphosis of Pleuroploca trapezium for successful life cycle closing and juvenile production

On captive breeding, spawning, embryonic and larval development in Horse conch, Pleuroploca trapezium (Linnaeus, 1758) from Southeast coast of India

Captive breeding, spawning and larval development of endangered gastropod, horse conch, Pleuroploca trapezium (Linnaeus, 1758) was studied and reported from Thoothukudi, Southeast coast of India for the first time. Wild collected brooders of P. trapezium were spawned after 10 months of rearing under captivity as a cluster of egg cases on the wall of the tank and also above the shell of the other horse conch. Each egg case had 150 to 460 numbers of eggs. The incubation period ranged from 23 to 30 days and 91 % of hatching was recorded. Detailed observations were made on the embryonic development and larval rearing until 40 days of post hatch (dph). The day one larvae measured 750±14.15 μm and reached an average shell size of 1830±37.48 µm after 40 dph. After 30 dph, though most of the pre-juveniles settled and crawled at the bottom of the rearing tank, the presence of active velum indicated that the competency to metamorphosis for the development of juvenile was not fully attained and complete mortality occurred. Therefore, further study is warranted using different cues to promote the metamorphosis of Pleuroploca trapezium for successful life cycle closing and juvenile production

Lessons on broodstock maintenance, spawning, larval rearing and juvenile production of marine gastropods of ornamental value

Research on marine gastropod breeding in India is in its infancy and scanty literature is only available. To fill the lacunae, marine gastropods of three ornamentally valued and conservation important groups such as Cyprids, Strombids and Muricids were held under captivity and studied for their broodstock maintenance, spawning behaviour, larval rearing and metamorphosis into juveniles at the Shellfish Hatchery of Central Marine Fisheries Research Institute, Tuticorin. Valuable information on the focal themes of the article was obtained for Strombids and Muricids leading to the successful life cycle closing for Lambis lambis and Chicoreus virgineus are reported earlier. In the present study, experiments were conducted on aspects such as post‐metamorphosed juvenile rearing up to 76 days post hatch for L. lambis, spawning, larval development and life cycle closing and reasonable level of juvenile production (8.8%) for Chicoreus ramosus. In addition, the primary observations on the captive breeding of Cypraea tigris with reference to its egg mass, brooding habit and early development is reported. However, while studying these groups few unanswered questions and bottle necks in their breeding nature, larval rearing and metamorphosis arose. The following account details the experiments conducted and results obtained in each of the focal themes of the paper and the constraints faced

Nanoenabling electrochemical sensors for life sciences applications

Electrochemical sensing systems are advancing into a wide range of new applications, moving from the traditional lab environment into disposable devices and systems, enabling real-time continuous monitoring of complex media. This transition presents numerous challenges ranging from issues such as sensitivity and dynamic range, to autocalibration and antifouling, to enabling multiparameter analyte and biomarker detection from an array of nanosensors within a miniaturized form factor. New materials are required not only to address these challenges, but also to facilitate new manufacturing processes for integrated electrochemical systems. This paper examines the recent advances in the instrumentation, sensor architectures, and sensor materials in the context of developing the next generation of nanoenabled electrochemical sensors for life sciences applications, and identifies the most promising solutions based on selected well established application exemplars