Scaling of anaerobic energy metabolism during tail flipping behaviour in the freshwater crayfish, Cherax destructor

1999 ◽  
Vol 50 (2) ◽  
pp. 183 ◽  
Author(s):  
J. Baldwin ◽  
A. Gupta ◽  
X. Iglesias
Keyword(s):  
Intracellular Ph ◽  
Body Mass ◽  
Arginine Kinase ◽  
Anaerobic Capacity ◽  
Glycolytic Enzyme ◽  
Time To Exhaustion ◽  
Freshwater Crayfish ◽  
Positive Allometry ◽  
Ph Buffering ◽  
Cherax Destructor

The allometry of anaerobic metabolism during escape behaviour was examined in the freshwater crayfish, Cherax destructor. Exercise time to exhaustion, and the total number of tail flips, increased with body mass. Concentrations of arginine phosphate and glycogen in the tail musculature of resting-state animals were independent of body mass, as was glycogen concentration following exercise to exhaustion. Lactate produced during exhaustive exercise, and intracellular pH buffering capacity, showed positive allometry. Activities of phosphorylase, phosphofructokinase and lactate dehydrogenase in the tail musculature showed positive allometry, while arginine kinase activity was independent of body mass. The positive allometry of anaerobic scope, reflected in the scaling of glycolytic enzyme activities, scales with the increased power required by larger animals to overcome drag during locomotion through water. The increased capacity for anaerobic muscle work in larger animals scales with anaerobic glycolytic capacity, while the contribution from phosphagen hydrolysis remains constant. Limits to anaerobic capacity are not set by fuel stores, but may involve inhibition of glycolytic enzymes at low pH, and the scaling of intracellular pH buffering. The positive allometry of anaerobic capacity observed for enforced exercise may not be used routinely in nature because of metabolic constraints imposed during recovery.

Phylogeny of the Australian freshwater crayfish Cherax destructor-complex (Decapoda : Parastacidae) inferred from four mitochondrial gene regions

2005 ◽  
Vol 19 (3) ◽  
pp. 209 ◽  
Author(s):  
Thuy T. T. Nguyen ◽  
Christopher M. Austin
Keyword(s):  
16S Rrna ◽  
Cytochrome Oxidase ◽  
Mitochondrial Gene ◽  
Large Subunit ◽  
Strong Support ◽  
Interspecific Variation ◽  
Rrna Gene ◽  
Freshwater Crayfish ◽  
Cherax Destructor ◽  
Australian Freshwater

The phylogenetic relationships among 32 individuals of Australian freshwater crayfish belonging to the Cherax destructor-complex were investigated using a dataset comprising sequences from four mitochondrial gene regions: the large subunit rRNA (16S rRNA), cytochrome oxidase I (COI), adenosine triphosphatase 6 (ATPase 6), and cytochrome oxidase III (COIII). A total of 1602 bp was obtained, and a combined analysis of the data produced a tree with strong support (bootstrap values 94–100%) for three divergent lineages, verifying the phylogenetic hypotheses of relationships within the C. destructor species-complex suggested in previous studies. Overall, sequences from the 16S rRNA gene showed the least variation compared to those generated from protein coding genes, which presented considerably greater levels of divergence. The level of divergence within C. destructor was found to be greater than that observed in other species of freshwater crayfish, but interspecific variation among species examined in the present study was similar to that reported previously.

scholarly journals Mechanics of evolutionary digit reduction in fossil horses (Equidae)

2017 ◽  
Vol 284 (1861) ◽  
pp. 20171174 ◽  
Author(s):  
Brianna K. McHorse ◽  
Andrew A. Biewener ◽  
Stephanie E. Pierce
Keyword(s):  
Body Mass ◽  
Bone Geometry ◽  
Continuous Measure ◽  
Positive Allometry ◽  
Load Bearing ◽  
Beam Analysis ◽  
Body Sizes ◽  
Major Trend ◽  
The Cost

Digit reduction is a major trend that characterizes horse evolution, but its causes and consequences have rarely been quantitatively tested. Using beam analysis on fossilized centre metapodials, we tested how locomotor bone stresses changed with digit reduction and increasing body size across the horse lineage. Internal bone geometry was captured from 13 fossil horse genera that covered the breadth of the equid phylogeny and the spectrum of digit reduction and body sizes, from Hyracotherium to Equus . To account for the load-bearing role of side digits, a novel, continuous measure of digit reduction was also established—toe reduction index (TRI). Our results show that without accounting for side digits, three-toed horses as late as Parahippus would have experienced physiologically untenable bone stresses. Conversely, when side digits are modelled as load-bearing, species at the base of the horse radiation through Equus probably maintained a similar safety factor to fracture stress. We conclude that the centre metapodial compensated for evolutionary digit reduction and body mass increases by becoming more resistant to bending through substantial positive allometry in internal geometry. These results lend support to two historical hypotheses: that increasing body mass selected for a single, robust metapodial rather than several smaller ones; and that, as horse limbs became elongated, the cost of inertia from the side toes outweighed their utility for stabilization or load-bearing.

scholarly journals Ontogenetic scaling patterns and functional anatomy of the pelvic limb musculature in emus (Dromaius novaehollandiae)

2014 ◽  
Author(s):  
Luis P Lamas ◽  
Russell P Main ◽  
John R. Hutchinson
Keyword(s):  
Body Mass ◽  
Functional Anatomy ◽  
Major Axis ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Fascicle Length ◽  
Cross Sectional ◽  
Positive Allometry ◽  
Dromaius Novaehollandiae ◽  
Pelvic Limb

Emus (Dromaius novaehollandiae) are exclusively terrestrial, bipedal and cursorial ratites with some similar biomechanical characteristics to humans. Their growth rates are impressive as their body mass increases eighty-fold from hatching to adulthood whilst maintaining the same mode of locomotion throughout life. These ontogenetic characteristics stimulate biomechanical questions about the strategies that allow emus to cope with their rapid growth and locomotion, which can be partly addressed via scaling (allometric) analysis of morphology. In this study we have collected pelvic limb anatomical data (muscle architecture, tendon length, tendon mass and bone lengths) and calculated muscle physiological cross sectional area (PCSA) and average tendon cross sectional area from emus across three ontogenetic stages (n=17, body masses from 3.6 to 42 kg). The data were analysed by reduced major axis regression to determine how these biomechanically relevant aspects of morphology scaled with body mass. Muscle mass and PCSA showed a marked trend towards positive allometry (26 and 27 out of 34 muscles respectively) and fascicle length showed a more mixed scaling pattern. The long tendons of the main digital flexors scaled with positive allometry for all characteristics whilst other tendons demonstrated a less clear scaling pattern. Finally, the two longer bones of the limb (tibiotarsus and tarsometatarsus) also exhibited positive allometry for length and the two others (femur and first phalanx of digit III) had trends towards isometry. These results indicate that emus experience a relative increase in their muscle force-generating capacities, as well as potentially increasing the force-sustaining capacities of their tendons, as they grow. Furthermore, we have clarified anatomical descriptions and provided illustrations of the pelvic limb muscle-tendon units in emus.

scholarly journals Ontogenetic scaling patterns and functional anatomy of the pelvic limb musculature in emus (Dromaius novaehollandiae)

2014 ◽  
Author(s):  
Luis P Lamas ◽  
Russell P Main ◽  
John R. Hutchinson
Keyword(s):  
Body Mass ◽  
Functional Anatomy ◽  
Major Axis ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Fascicle Length ◽  
Cross Sectional ◽  
Positive Allometry ◽  
Dromaius Novaehollandiae ◽  
Pelvic Limb

Emus (Dromaius novaehollandiae) are exclusively terrestrial, bipedal and cursorial ratites with some similar biomechanical characteristics to humans. Their growth rates are impressive as their body mass increases eighty-fold from hatching to adulthood whilst maintaining the same mode of locomotion throughout life. These ontogenetic characteristics stimulate biomechanical questions about the strategies that allow emus to cope with their rapid growth and locomotion, which can be partly addressed via scaling (allometric) analysis of morphology. In this study we have collected pelvic limb anatomical data (muscle architecture, tendon length, tendon mass and bone lengths) and calculated muscle physiological cross sectional area (PCSA) and average tendon cross sectional area from emus across three ontogenetic stages (n=17, body masses from 3.6 to 42 kg). The data were analysed by reduced major axis regression to determine how these biomechanically relevant aspects of morphology scaled with body mass. Muscle mass and PCSA showed a marked trend towards positive allometry (26 and 27 out of 34 muscles respectively) and fascicle length showed a more mixed scaling pattern. The long tendons of the main digital flexors scaled with positive allometry for all characteristics whilst other tendons demonstrated a less clear scaling pattern. Finally, the two longer bones of the limb (tibiotarsus and tarsometatarsus) also exhibited positive allometry for length and the two others (femur and first phalanx of digit III) had trends towards isometry. These results indicate that emus experience a relative increase in their muscle force-generating capacities, as well as potentially increasing the force-sustaining capacities of their tendons, as they grow. Furthermore, we have clarified anatomical descriptions and provided illustrations of the pelvic limb muscle-tendon units in emus.

Gill and Body Surface Areas of the Carp in relation to Body Mass, With Special Reference To The Metabolism-Size Relationship

1985 ◽  
Vol 117 (1) ◽  
pp. 1-14 ◽  
Author(s):  
SHIN OIKAWA ◽  
YASUO ITAZAWA
Keyword(s):  
Special Reference ◽  
Body Mass ◽  
Body Surface ◽  
Larval Stage ◽  
The Body ◽  
Positive Allometry ◽  
Surface Areas ◽  
Gill Area ◽  
Resting Metabolism ◽  
The Relationship

The relationships of resting metabolism per unit mass of body to gill and body surface areas were examined by measuring gill, body surface and fin areas of carp ranging from 0.0016 to 2250g. There was a triphasic allometry for the relationship between gill area and body mass: during the prelarval (0.0016–0.003 g) and postlarval (0.003–0.2g) stages there was a positive allometry (slopes of 7.066 and 1.222, respectively), during the juvenile and later stages (0.2–2250 g) there was a negative allometry with a slope of 0.794. There was a diphasic negative allometry for the relationship between surface area of the body or the fins and body mass, with a slope of 0.596 or 0.523 during the larval stage and 0.664 or 0.724 during the juvenile and later stages, respectively. Except for the 3rd phase (juvenile to adult) of gill area, these slopes were significantly different (P<0.01) from the slope for the relationship between resting metabolism and body mass of intact carp (0.84; value from Winberg, 1956). It is considered, therefore, that gill, body surface and fin areas do not directly regulate the resting metabolism of the fish, in the larval stage at least.

Validity and Reliability of a New Karate-Specific Aerobic Field Test for Karatekas

2014 ◽  
Vol 9 (6) ◽  
pp. 953-958 ◽  
Author(s):  
Montassar Tabben ◽  
Jeremy Coquart ◽  
Helmi Chaabène ◽  
Emerson Franchini ◽  
Karim Chamari ◽  
...  
Keyword(s):  
Oxygen Uptake ◽  
Laboratory Test ◽  
Body Mass ◽  
Field Test ◽  
Scientific Data ◽  
Rating Of Perceived Exertion ◽  
Time To Exhaustion ◽  
Validity And Reliability ◽  
Specific Field ◽  
Significant Difference

Purpose:This study determined the validity and reliability of a new specific field test that was based on the scientific data from the latest research.Methods:Seventeen international-level karatekas participated in the study: 14 men (age 24.1 ± 4.6 y, body mass 65.7 ± 10.8 kg) and 3 women (age 19 ± 3.6 y, body mass 54.1 ± 0.9 kg). All performed the new karate-specific test (KST) 2 times (test and retest sessions were carried out on separated occasions 1 wk apart). Thirteen men also performed a laboratory test to assess maximal oxygen uptake (VO2max).Results:Test–retest results showed the KST to be reliable. Peak oxygen uptake (VO2peak), peak heart rate (HRpeak), blood lactate concentration, rating of perceived exertion, and time to exhaustion (TE) did not display a difference between the test and the retest. The SEM and ICC for relative and absolute VO2peakand TE were <5% and >.90, respectively. Significant correlations were found between VO2peak(mL · kg−1· min−1) and TE measured from the KST (r= .71, 95%CI 0.35–0.88,P< .0001). There was also no significant difference between VO2peakmeasured from the KST and VO2maxrecorded from the cycle-ergometer laboratory test (55.1 ± 4.8 vs 53.2 ± 6.6 mL · kg−1· min−1, respectively;t= –1.85, df = 12,P= .08,dz= 0.51 [small]). The Bland and Altman analyses reported a mean difference (bias) ± the 95% limits of agreement of 1.9 ± 7.35 mL · kg−1· min−1.Conclusions:This study showed that the new KST test, with effort patterns replicating real karate combat sessions, can be considered a valid and reliable karate-specific field test for assessing karatekas’ endurance fitness.

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