Immobilization of decapod Crustacea for experimental procedures

1977 ◽  
Vol 57 (3) ◽  
pp. 715-721 ◽  
Author(s):  
R. L. Oswald
Keyword(s):  
Carbon Dioxide ◽  
Experimental Work ◽  
Anaesthetic Techniques ◽  
Anaesthetic Drug ◽  
Cancer Pagurus ◽  
Neurophysiological Studies ◽  
Decapod Crustacea ◽  
Aquatic Vertebrate ◽  
Magnesium Salts

Although anaesthetic techniques are well established for most of the vertebrates, methods for the invertebrates are generally not well documented. The decapod Crustacea are widely used for neurophysiological studies involving the implant of chronic electrodes and other techniques. With sluggish species such as Cancer pagurus some workers simply give the animal an object to grasp and perform their operations in the unanaesthetized condition. Others use hypothermia to immobilize their animals, although this may result in autotomy of appendages. Other methods include immersion in solutions of ethanol, magnesium salts (Pantin, 1946), or carbon dioxide. Conventional aquatic vertebrate anaesthetics such as MS-222 (Sandoz) are generally ineffective by immersion in decapods. This short investigation has set out to find out if a suitable anaesthetic drug is available for experimental work and for live dissections.

scholarly journals Supersonic dispersion in gases

1934 ◽  
Vol 146 (856) ◽  
pp. 56-71 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Experimental Work ◽  
High Frequency ◽  
Response Curve ◽  
Wave Length ◽  
Soap Film ◽  
The Other ◽  
Rapid Degradation ◽  
Compressional Waves ◽  
Point Electrode

The rapid degradation of intensity suffered by compressional waves of high frequency in gases was first observed by pierce in carbon dioxide for frequencies in the neighbourhood of 2.10 5 cycles/sec. Although in the last few years a considerable number of measurements of the velocity of supersonic waves have been made, less experimental work has been done on the absorption . This present paper describes some work aimed at elucidating the mechanism of the phenomenon. Consideration was first given to the establishment of a source of vibrations of the requisite frequency. The possible apparatus reduces itself to four types: (1) edge-tones, (2) electric sparks, (3) small resonators of gas, (4) solid resonators; both of the latter types to be maintained by oscillating circuits incorporating valves. The frequency of an edge-tone depends directly on the velocity of the blast, and inversely on the distance from the blower to the edge, so that it should be possible to produce supersonic waves by making the former very large and the latter very small; in fact, Hartmann has already used such a source. The difficulty of maintaining constant blast velocity and the complications which the blast introduces in the propagation of such waves would, however, have made such a source unmanageable in the present work. Nekle-pajev has used sparks as sources in the examination of the absorption in air. But here again the frequency is difficult to measure or to maintain constant. Some success was obtained by the author with gaseous resonators consisting of short brass tubes terminated at one end by a brass stopper, and at the other end by a soap film, the distance between the two being half the wave-length at the frequency of excitation. The resonator was maintained in vibration by a valve oscillator, of which the plate was connected to a point electrode just above the soap film, while the grid was connected to the brass tube itself. Response of the resonator due to electrostatic attraction of the film was observed by the image of a glowing filament reflected from the slightly concave film on to a scale. By varying the tuning of the oscillator the response curve of the little resonator could be obtained.

scholarly journals Non-invasive MRI Studies of Ventilatory and Cardiovascular Performance in Edible Crabs Cancer pagurus During Warming Under Elevated CO2 Levels

2021 ◽  
Vol 11 ◽  
Author(s):  
Bastian Maus ◽  
Sebastian Gutsfeld ◽  
Christian Bock ◽  
Hans-Otto Pörtner
Keyword(s):  
Oxygen Uptake ◽  
Thermal Tolerance ◽  
Decapod Crustacean ◽  
Temperature Dependent ◽  
Non Invasive ◽  
Cancer Pagurus ◽  
Decapod Crustacea ◽  
Infra Red ◽  
Cardiovascular Performance ◽  
Flow Through

The thermal tolerance of marine decapod crustacea is defined through their capacities for oxygen uptake and distribution. High ambient CO2 levels were previously shown to reduce hemolymph oxygen levels at enhanced cardiac performance during warming. This study investigated the impacts of warming under two CO2 levels on ventilation and hemolymph circulation in edible crabs Cancer pagurus. It also highlights changes in the ventilatory and cardiac pauses displayed by Decapoda under routine metabolism. Animals were exposed to step-wise, sub-critical warming (12–20°C over 5 days) under control (470 μatm) and high (1,350 μatm) water PCO2. Flow-through respirometry was combined with magnetic resonance imaging and infra-red photoplethysmography to allow for simultaneous, non-invasive measurements of metabolic rates (M˙O2), ventilation and cardiovascular performance. Crabs spent significantly more time in a low M˙O2 state (metabolic pause), when experiencing high CO2 conditions above 16°C, compared to normocapnic warming. Heart rates leveled off beyond 18°C at any CO2 level. Cardiac output continued to increase with high-CO2-warming, due to elevated cardiac stroke volumes. Consequently, temperature-dependent branchial hemolymph flow remained unaffected by CO2. Instead, a suppressing effect of CO2 on ventilation was found beyond 16°C. These results indicate constrained oxygen uptake at stable cardiovascular performance in a decapod crustacean.Cancer pagurus: urn:lsid:zoobank.org:act:B750F89A-84B5-448B-8D80-EBD724A1C9D4

XX.—The Diffusion Coefficients of Bromine-Hydrogen, Bromine-Nitrogen, Bromine-Oxygen, and Bromine-Carbon Dioxide

1933 ◽  
Vol 52 ◽  
pp. 337-344 ◽  
Author(s):  
John E. Mackenzie ◽  
Harry W. Melville
Keyword(s):  
Carbon Dioxide ◽  
Diffusion Coefficient ◽  
Experimental Work ◽  
Diffusion Coefficients ◽  
Visual Method ◽  
Good Accordance ◽  
History Of ◽  
Diffusion Of Gases

SummaryA brief history of the measurement of diffusion of gases (excluding “effusion,” “transpiration,” and other processes from which data for the calculation of the diffusion coefficient may be obtained) is given.A visual method of following the diffusion of a strongly coloured vapour (bromine) into colourless gases is described.The diffusion coefficients calculated from the observed data are in good accordance with those obtained theoretically.The authors desire to thank Miss Netta Macnaughton for valuable assistance in the experimental work.

scholarly journals On the nature and permeability of chitin. I.--The chitin lining the foregut of decapod crustacea and the function of the tegumental glands

1932 ◽  
Vol 111 (772) ◽  
pp. 298-329 ◽  
Keyword(s):  
External Medium ◽  
Specific Rotation ◽  
The Body ◽  
Animal Kingdom ◽  
Entire Surface ◽  
Large Size ◽  
Research Material ◽  
Cancer Pagurus ◽  
Decapod Crustacea ◽  
Average Size

Chitin is widely distributed throughout the animal kingdom and also occurs in the Fungi. Wester (1910) has shown that it is present in all Arthropods, invariably in the exoskeleton and lining the respiratory systems and except in some Arachnids, in the greater part of the gut. In the Mollusca it occurs in the jaws and radulæ, in the shell and sometimes in the gut of Cephalopods and sometimes in the shell and lining of siphons in Lamellibranchs. The setæ of Annelids are of chitin and occasionally, as in Lumbricus and Aphrodile , the gut is lined with it. Chitin is also present in the shell, peduncle and spines of some Brachiopods, e. g., Lingula, in some Plyzoa, in the Hydroids and very occasionally, as in the gemmules of Spongilla, in the porifera. According to Wester, it never occurs in protoza, Echinodrema, worms other than Annelids or in vertebrates. Wherever it occur, chitin gives the same chemical reactions (Zander, 1897 ; Wester, 1910) and has the same physical properties, e. g., specific gravity and refractive index (Sollas, 1907 ; Becking and Chamberlin, 1925) and specific rotation which is always lævorotatory (Irvine, 1909). It is surprising that so little is known about the properties of this very important substance. In the Arthropods especially, where it covers the entire surface of the body and where respiration and in some cases absorption in the gut-indeed practically all interchange between the interior of the body and the external medium-must take place through it, exact knowledge of the permeability of chitin and of the condition which control this is clearly essential for a full understanding of the life of the animal. It was the almost complete absence of knowledge on this subject which led to the initiation of this series of researches. Ideal material for this purpose was found in the uncalcified chitin which lines the foregut (“œesphagus” and “stomach”) of the Decapod Crustacea, of which relatively large pieces can be obtained from animals of average size. The lobster, Homarus vulgaris , owing to the relatively large size of the foregut, provided the great bulk of the research material, other large Decapods, such a Palinurus vulgaris , Cancer pagurus, Maia squinado and Carcinus mœnas , being used for comparative purposes.

Gill Ventilation Volumes, Oxygen Consumption and Respiratory Rhythms in Carcinus Maenas (L.)

1964 ◽  
Vol 41 (2) ◽  
pp. 309-321
Author(s):  
K. D. ARUDPRAGASAM ◽  
E. NAYLOR
Keyword(s):  
Carbon Dioxide ◽  
Oxygen Consumption ◽  
Prolonged Exposure ◽  
Respiratory Activity ◽  
Carcinus Maenas ◽  
Oxygen Depletion ◽  
Decapod Crustacea ◽  
Gill Ventilation ◽  
Respiratory Rhythms ◽  
Pumping Activity

1. An apparatus is described for continuously measuring gill ventilation volumes in crabs. 2. Large Carcinus pump about 1 c.c./g./min. and consume oxygen at the rate of about 0.03 c.c./g./hr. whilst smaller specimens pump up to 1.5 c.c./g./min. and consume up to 0.1 c.c./g./hr. Freshly collected crabs show persistent tidal and 24 hr. rhythms of pumping activity and oxygen consumption. 3. In response to oxygen depletion Carcinus shows increased rates of gill ventilation and increased percentage utilization. Prolonged exposure to increased carbon dioxide results in a short-lived inhibition followed by over-compensation and then progressive inhibition of respiratory activity. 4. The results are discussed in relation to previous work on respiration in other decapod Crustacea.

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