Studies On Spiny Lobster Fishery Of South West Coast Of India

A study on the different aspects of spiny lobster fishery of south west coast of India with respect to the factors relevant to production, including conservation and management measures for putting this fishery on sound basis needs no emphasis. There are some aspects of this fishery which have not been sufficiently inquired into and some others which have been touched upon intermittantly and in a languid way. The attempt here is to throw light on these aspects from a production point of view. Emphasis is on harvest technology and the conservation and management measures and it is proposed to make a critical review of such measures in vogue in other lobster fishing countries and discuss about suitable methods for this fishery

Withania somnitera and withanolide a mediated restoration of AMPA and NMDA receptor function in pilocarpine induced temporal lobe epilepsy

The onset of spontaneous seizures triggers a cascade of molecular and cellular events that eventually leads to neuronal injury and cognitive decline. The present study investigated the effect of Withania somnifera (WS) root extract and Withanolide A (WA) in restoring behavioural deficit by inhibiting oxidative stress induced alteration in glutamergic neurotransmission. The subdued performance in behavioural tests shows impaired motor coordination and memory. Histopathological investigations revealed significant neuronal loss in hippocampus of epileptic rats indicating glutamate mediated excitotoxicity. The treatment with WS and WA restored behavioural deficit and ameliorated neuronal loss. An altered redox homeostasis leading to oxidative stress is a hallmark of TLE. The antioxidant potential was afflicted in epileptic rats, evident from altered activity of SOD and CAT, down regulation of SOD and GPX expression and enhanced lipid peroxidation. The antioxidant property of WS and WA restored altered antioxidant capacity. Alteration in GDH activity and down regulation of GLAST expression resulted in enhanced glutamate content in the brain regions. The metabolism of glutamate was altered in the form of down regulated GAD expression. The alteration in synthesis, transport and metabolism resulted in further increase of the glutamate concentration at the synapse leading to glutamate mediated excitotoxicity. The decreased NMDA and AMPA receptor binding and down regulated NMDA R1, NMDA 2B and AMPA (GluR2) mRNA expression indicated altered glutamergic receptor function. The treatment with WS and WA reversed altered glutamergic receptor function, synthesis, transport and metabolism. The enhanced levels of second messenger IP3 responsible for Ca2+ mediated toxicity was reversed after treatment with WS and WA. Neurotoxics concentration of glutamate resulted in up regulation of pro apoptotic factors Bax and Caspase 8 and down regulation of anti apoptotic factor Akt resulting in neuronal death. The treatment with WS and WA resulted in activation of Akt and down regulation of Bax and caspase 8 leading to blocking of apoptotic pathway. The treatment with WS and WA resulted in reduced seizure frequency and amelioration of associated alterations suggesting the therapeutic role of Withania somnifera in temporal lobe epilepsy

Energetics 0f A Few Marine Crustaceans

Success achieved in seed production and culture of prawns induced researchers to explore the feasibiltiy of culture of other important crustaceans like lobsters and crabs. The CMFRI initiated a project to study the prospects of spiny lobster’ culture and I was associated with this project from the beginning. Compared to shrimp farming, culture of spiny lobsters is an entirely different proposition due to inherent problems in producing their seeds. The emphasis on .obster culture, therefore, shifted to rearing of juvenile lobsters, which form a major portion in commercial lobster landings in India. Commendable success was achieved in enhancing growth rate of four important speices of spiny lobsters by bilateral eyestalk ablation. But due to strong reservations expressed against the "blinding" of lobsters by people from all walks of life, this technique could not be tested commercially for its economic viability. As in prawns, energetics of reproduction and egg development have not yet been documented in spiny lobsters and so these aspects were included in this study. Though some limited informations on food conversion efficiency are availble in spiny lobster, a detailed study on the effect of size and sexual maturity on food conversion was wanting and this also was included in this investigation. The most dominant spiny lobster in south east and south west coast of India, Panulirus homarus (Linnaeus) was selected for this study. Uptake, accumulation and utilization of minerals and trace elements are important events during embryogenesis of aquatic invertebrates. The scope of this study was widened to include these aspects also in order to understand how specific requirements of minerals and trace elements are met in the developing eggs of these two species of crustaceans.