Long-duration anesthetization of squid (Doryteuthis pealeii)

The effects of prospective anaesthetic substances on cephalopods: Summary of original data and a brief review of studies over the last two decades

“…Basic body muscle tone and posture, 'sticky' suckers, tactile and visual reflexes are all retained throughout, although visual awareness may be somewhat dulled. Also typical is a hypersensitive response to tactile stimuli, even from a very gentle knock on the laboratory bench; there are frequent rapid colour changes between pale and dark; spontaneous deimatic displays; flashing of chromatophores on the body and on the base of the arms (not usually seen on the arms themselves); exaggerated raising of papillae, especially around the eyes and sometimes on the dorsal Estefanell et al, 2011;García-Franco, 1992;Ikeda et al, 2009;Lange and Hartline, 1974;Miyan and Messenger, 1995;Mooney et al, 2010;Patterson and Silver, 1983;Shomrat et al, 2011;Silver et al, 1983;present study); (successful, but inking often seen: Andrews and Tansey, 1981;Froesch and Marthy, 1975 mantle; sporadic jerking movements (sometimes including sudden rotations of up to 20°), sudden widening of pupils, convulsions, defaecation and copious inking. On some occasions, the mantle takes on a strange, abnormal lageniform appearance, where the posterior 20-25% of the mantle remains unusually constricted while the main part of the mantle musculature continues the typical cycle of expanding and contracting movements associated with irrigation of the gills during breathing.…”

“…Concentrations used (see Table 3) were of the same order of magnitude reported in the literature as effective for anaesthesia. The neuromuscular blocking agent gallamine has been administered only by injection previously (Mooney et al, 2010) but here it was included to investigate possible adjunct neuromuscular or anaesthetic effects via immersion. Similarly, nicotine sulphate was investigated in view of reports that tobacco has been used to relax the grip of octopuses (Bartsch, 1917), to narcotize other invertebrates, with effects including the arrest of cilia in Mytilus (Pantin, 1946), and to anaesthetise fish (Marking and Meyer, 1985).…”

Peripheral injury induces long-term sensitization of defensive responses to visual and tactile stimuli in the squid Loligo pealeii, Lesueur 1821

“…In addition, in another mollusc, local or general anesthesia at the time of tissue injury can block development of behavioral sensitization by preventing neural activity at the injury site (Walters, 1987). Finally, the standard anesthesia for cephalopods is immersion in MgCl 2 solution (Messenger et al, 1985;Mooney et al, 2010), which causes muscle relaxation. The possibility of sustained loss of hemolymph after injury would have been increased without normal muscle contraction, potentially increasing mortality and morbidity.…”

Hearing pathways in the Yangtze finless porpoise,Neophocaena asiaeorientalis asiaeorientalis

“…This method is often used for calculating the modulating amplitude of these stimuli, which are most easily initially quantified by their peak-to-peak values (e.g. Mooney et al, 2010;Nachtigall et al, 2008;. SPLs of the clicks were measured using V p-p as is standard for measuring odontocete click intensities due to the inherent brevity of the signals (Au, 1993).…”