Egg collection and larval rearing of cephalopods- Winter School on Recent Advances in Breeding and Larviculture of Marine Finfish and Shellfish

摘要

Cephalopods are the largest, most active invertebrates. About 1, 17, 278 tonnes of cephalopods are exploitedudduring 2003 in India (Annam et al., 2004). During 2002-2003 India has exported 41,381 tonnes of frozen cuttlefish andud37838 tonnes of frozen squid valued at US$ 166.2 million to countries such as Japan, USA and the European Unionud(Anon, 2003). Cephalopods are unique because they are 85% protein by dry weight (16-21% by wet weight) (Lakshmananudand Balachandran, 2000) and are considered a delicacy in seafood restaurants. Recent years have witnessed audsignificant amount of research interest in cephalopod culture, in order to develop technology for commercial farmingudas well as to produce multiple laboratory generations for research in neurobiology (Minton et al. 2001). They are highlyudpromising biomedical models because of their giant axons and are of interest to neurobiologists. Squids 4 months oldudhave giant axons larger than 450ìm in diameter. Studies have shown that the ultrastructure and physiology of theseudsystems rival the sophistication of their vertebrate counterparts, the vestibular end organs and the vestibulo-oculomotorudsystem. In detail, many parallels exist, e.g., the dynamic response characteristics (gain and phase lag values) of theudcephalopod angular acceleration receptor systems are similar to those of the vertebrate semicircular canals, theudputative transmitters in the afferent and efferent fiber systems are similar, and the cephalopod brain pathways involvedudin oculomotor control have vertebrate-like organizations. Thus, these systems are interesting invertebrate models thatudcan substantially contribute to our understanding of the basic principles of morphology, physiology and pathology ofudthese systems in higher vertebrates, including man. Choe and Oshima (1963) and Choe (1966) reared three speciesudof the genus Sepia, the squid Sepioteuthis lessoniana and the sepiolid Euprymna berryi from egg to adult size.