The importance of the cloacal bursae as the primary site of aquatic respiration in the freshwater turtle,Elseya albagula

2010 ◽  
Vol 35 (2) ◽  
pp. 276-282 ◽  
Author(s):  
Sean FitzGibbon ◽  
Craig Franklin
Keyword(s):  
Primary Site ◽  
Freshwater Turtle ◽  
Aquatic Respiration

Seasonal changes in the diving performance of the bimodally respiring freshwater turtle Rheodytes leukops in a natural setting

2003 ◽  
Vol 81 (4) ◽  
pp. 617-625 ◽  
Author(s):  
Matthew A Gordos ◽  
Craig E Franklin ◽  
Colin J Limpus
Keyword(s):  
Metabolic Acidosis ◽  
Environmental Conditions ◽  
Seasonal Changes ◽  
Physiological State ◽  
Metabolic Cost ◽  
Freshwater Turtle ◽  
Natural Setting ◽  
Aquatic Respiration ◽  
Pressure Sensitive ◽  
Austral Autumn

The objective of this study was to investigate how seasonally fluctuating environmental conditions influence the diving performance of the highly aquatic, bimodally respiring turtle Rheodytes leukops in a natural setting. Over four consecutive seasons (Austral autumn 2000 to summer 2001), the diving behaviour of adult turtles was recorded via pressure-sensitive time–depth recorders within Marlborough Creek, central Queensland, Australia. Short surfacing intervals recorded for R. leukops in winter suggest that the species utilizes aquatic respiration as an overwintering strategy to prevent the development of a metabolic acidosis during the long inactive dives observed during the season. As water temperature increases and aquatic PO2 decreases, R. leukops switches from facultative to obligate air-breathing, presumably because of the increased metabolic cost associated with aquatic respiration under summer conditions. Increases in mean surfacing time from winter to spring and summer are attributed to seasonal changes in behaviour possibly associated with foraging rather than to the physiological state of the turtle, given that no difference in median surfacing time among seasons was observed.

Muddy waters: the influence of high suspended-sediment concentration on the diving behaviour of a bimodally respiring freshwater turtle from north-eastern Australia

2016 ◽  
Vol 67 (4) ◽  
pp. 505 ◽  
Author(s):  
Jason R. Schaffer ◽  
Mark Hamann ◽  
Richard Rowe ◽  
Damien W. Burrows
Keyword(s):  
Low Temperature ◽  
Suspended Sediment ◽  
Sediment Concentration ◽  
Dive Duration ◽  
Diving Behaviour ◽  
Freshwater Turtle ◽  
Freshwater Turtles ◽  
Aquatic Respiration ◽  
Eastern Australia ◽  
The Impact

Increased suspended-sediment concentrations (SS) in rivers can affect aquatic respiration in riverine fauna by impairing respiratory function. Bimodally respiring freshwater turtles are likely to be sensitive to changes in SS because increased concentrations may affect their ability to aquatically respire. However, the impact of SS on the diving behaviour of bimodally respiring freshwater turtles has not been formally investigated. To test this, we examined the influence of dissolved oxygen (DO) saturation (25%, 100%) and temperature (17°C, 25°C) on the diving behaviour of Elseya irwini under clear (0mgL–1) and turbid (79mgL–1) conditions. We hypothesised that low temperature and high DO % saturation would increase dive duration and that high SS would negate the effect of DO, decreasing dive duration under highly oxygenated conditions. Our data demonstrated that increased SS significantly reduced mean dive duration by 73% (97.4±10.1min in 0mgL–1 trials v. 26.4±3.2min in 79mgL–1 trials) under conditions of low temperature (17°C) and high DO % saturation (100%) only. Increased SS directly affects the utilisation of DO by this species, so as to extend submergence times (aquatic respiration) under optimal conditions, raising concerns about the effect of SS on the persistence of populations of physiologically specialised freshwater turtles.

The Intravascular Generation of Fibrinogen Derivatives and the Blood Vessel Wall in Venous Thrombosis and Disseminated Intravascular Coagulation

1977 ◽  
Vol 38 (04) ◽  
pp. 0831-0849 ◽  
Author(s):  
Gwendolyn J. Stewart
Keyword(s):  
Blood Vessel ◽  
Venous Thrombosis ◽  
Vessel Wall ◽  
Fluid Phase ◽  
Primary Site ◽  
Blood Vessel Wall ◽  
Fibrin Deposition ◽  
Tissue Destruction ◽  
Fibrin Formation ◽  
Rich Material

SummaryBoth deep venous thrombosis and DIC are intermediate mechanisms of disease – both are a consequence of the deposition of fibrin-rich material in blood vessels some distance from the primary site of tissue destruction. The great difference in the sites of fibrin deposition may depend on the extent and site of activation of the clotting mechanism. DIC likely occurs in the fluid phase of the blood as a consequence of massive fibrin formation while thrombosis results from limited fibrin formation at the interface between blood and vessel wall. Leukocytes may be essential for attaching thrombi to the vessel wall in many places.

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