Aspects of the Respiratory Physiology of the Swimming Crab Liocarcinus depurator (Linnaeus)

Gale, Gordon Ferguson (1986) Aspects of the Respiratory Physiology of the Swimming Crab Liocarcinus depurator (Linnaeus). MSc(R) thesis, University of Glasgow.

Abstract

The swimming crab, Liocarcinus depurator (L.), is one of the commonest portunid crabs in the inshore waters around the British Isles. Experimental animals were obtained from the Clyde Sea Area where the species is commonly trawled at a depth of 40 - 50 metres. As background, the respiratory physiology of decapod crustaceans including blood chemistry is succinctly reviewed. The branchial morphology of L. depurator is then described. It conforms to the typical portunid pattern. Using the impedance pneumograph and pressure transducer techniques, the heart rate, scaphognathite rate and the branchial pressure were recorded and analysed. The heart and scaphognathite beat of L. depurator is extremely variable both between individuals and within an individual crab. Periods of cardiac arrest and ventilatory apnoea have been shown to occur. Cardiac arrest and apnoea occur synchronously. Reversals of the respiratory current occurred regularly under normoxic conditions in crabs that were not buried. When the crab was buried in the substratum the scaphognathites maintained almost permanent reversal of the respiratory current. It was shown that after a minimum of twelve hours the incidence of reversals and the periodicity of cardiac arrests became relatively predictable and this was indicative of a relatively unstressed crab. The oxygen consumption of L. depurator was determined using a closed system respirometer. It was found that a minimum of twelve hours was required in order to overcome the stress of handling prior to being placed in the respirometer and for an unstressed oxygen consumption rate to be determined. A Q10 value for L. depurator was determined and the difference in oxygen consumption between fed and unfed animals was also examined. Investigations of oxygen consumption during hypoxia produced a range of Pc values which were related to the wet weight of the crab.

• Item Type: Thesis (MSc(R))
• Qualification Level: Masters
• Keywords: Zoology, Physiology
• Date of Award: 1986
• Depositing User: Enlighten Team
• Unique ID: glathesis:1986-77446
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 14 Jan 2020 09:08
• Last Modified: 14 Jan 2020 09:08
• URI: https://theses.gla.ac.uk/id/eprint/77446