Fenitrothion, an organophosphate, affects running endurance but not aerobic capacity in fat-tailed dunnarts (Sminthopsis crassicaudata).

We measured aerobic metabolism during cold exposure and exercise performance (run duration and oxygen consumption while running at 1 m s(-1)) in the fat-tailed dunnart Sminthopsis crassicaudata, a dasyurid marsupial, before and after ingestion of 30 mg kg(-1) of fenitrothion, an organophosphate (OP) pesticide. Running endurance of OP-exposed animals was less than half that of control animals over the first 3 days after dosing and 55% of control animal endurance on day 5 post-dose. Despite these declines, peak metabolic rate at this running speed (9.

Exercise training enhances aerobic capacity in juvenile estuarine crocodiles (Crocodylus porosus).

Aerobic capacity (VO2max) of endothermic vertebrates is known to increase with exercise training, but this effect has not been found to-date in non-avian reptiles. We exercised juvenile estuarine crocodiles (Crocodylus porosus) to walk at 0.75-0.

Control of jaw movements in two species of macropodines (Macropus eugenii and Macropus rufus).

The masticatory motor patterns of three tammar wallabies and two red kangaroos were determined by analyzing the pattern of electromyographic (EMG) activity of the jaw adductors and correlating it with lower jaw movements, as recorded by digital video and videoradiography. Transverse jaw movements were limited by the width of the upper incisal arcade. Molars engaged in food breakdown during two distinct occlusal phases characterized by abrupt changes in the direction of working-side hemimandible movement.

Modulation of proximal muscle function during level versus incline hopping in tammar wallabies (Macropus eugenii).

We examined the functional role of two major proximal leg extensor muscles of tammar wallabies during level and inclined hopping (12 degrees, 21.3% grade). Previous in vivo studies of hopping wallabies have revealed that, unlike certain avian bipeds, distal hindlimb muscles do not alter their force-length behavior to contribute positive work during incline hopping.

Routine metabolic rate of southern bluefin tuna (Thunnus maccoyii).

Routine metabolic rate (RMR) was measured in fasting southern bluefin tuna, Thunnus maccoyii, the largest tuna species studied so far (body mass=19.6 kg (+/-1.9 SE)).

Differential design for hopping in two species of wallabies.

Hindlimb musculoskeletal anatomy and steady speed over ground hopping mechanics were compared in two species of macropod marsupials, tammar wallabies and yellow-footed rock wallabies (YFRW). These two species are relatively closely related and are of similar size and general body plan, yet they inhabit different environments with presumably different musculoskeletal demands. Tammar wallabies live in relatively flat, open habitat whereas yellow-footed rock wallabies inhabit steep cliff faces.

Energetics of swimming by the ferret: consequences of forelimb paddling.

The domestic ferret (Mustela putorius furo) swims by alternate strokes of the forelimbs. This pectoral paddling is rare among semi-aquatic mammals. The energetic implications of swimming by pectoral paddling were examined by kinematic analysis and measurement of oxygen consumption.

Development of maximum metabolic rate and pulmonary diffusing capacity in the superprecocial Australian Brush Turkey Alectura lathami: an allometric and morphometric study.

The Australian Brush Turkey Alectura lathami is a member of the Megapodiidae, the mound-building birds that produce totally independent, "superprecocial" hatchlings. This study examined the post-hatching development of resting and maximal metabolic rates, and the morphometrically determined changes in pulmonary gas exchange anatomy, in chicks during 3.7 months of growth from hatchlings (122 g) to subadults (1.

An allometric study of lung morphology during development in the Australian pelican, Pelicanus conspicillatus, from embryo to adult.

Pelicans produce altricial chicks that develop into some of the largest birds capable of sustained flight. We traced pulmonary morphological development in the Australian pelican, Pelicanus conspicillatus, from third trimester embryos to adults. We described growth and development with allometric relationships between lung components and body mass or lung volume, according to the equation y = ax(b).

The mechanics of jumping versus steady hopping in yellow-footed rock wallabies.

The goal of our study was to explore the mechanical power requirements associated with jumping in yellow-footed rock wallabies and to determine how these requirements are achieved relative to steady-speed hopping mechanics. Whole body power output and limb mechanics were measured in yellow-footed rock wallabies during steady-speed hopping and moving jumps up to a landing ledge 1.0 m high (approximately 3 times the animals' hip height).

An immunomodulator used to protect young in the pouch of the Tammar wallaby, Macropus eugenii.

Eugenin [pGluGlnAspTyr(SO(3))ValPheMetHisProPhe-NH(2)] has been isolated from the pouches of female Tammar wallabies (Macropus eugenii) carrying young in the early lactation period. The sequence of eugenin has been determined using a combination of positive and negative ion electrospray mass spectrometry. This compound bears some structural resemblance to the mammalian neuropeptide cholecystokinin 8 [AspTyr(SO(3))MetGlyTrpMetAspPhe-NH(2)] and to the amphibian caerulein peptides [caerulein: pGluGlnAspTyr(SO(3))ThrGlyTrpMetAspPhe-NH(2)].

Joint work and power associated with acceleration and deceleration in tammar wallabies (Macropus eugenii).

Measurements of joint work and power were determined using inverse dynamics analysis based on ground reaction force and high-speed video recordings of tammar wallabies as they decelerated and accelerated while hopping over a force platform on level ground. Measurements were obtained over a range of accelerations ranging from -6 m s(-2) to 8 m s(-2). The goal of our study was to determine which joints are used to modulate mechanical power when tammar wallabies change speed.

Partitioning of respiration between the gills and air-breathing organ in response to aquatic hypoxia and exercise in the pacific tarpon, Megalops cyprinoides.

The evolution of air-breathing organs (ABOs) is associated not only with hypoxic environments but also with activity. This investigation examines the effects of hypoxia and exercise on the partitioning of aquatic and aerial oxygen uptake in the Pacific tarpon. The two-species cosmopolitan genus Megalops is unique among teleosts in using swim bladder ABOs in the pelagic marine environment.

Developmental allometry of pulmonary structure and function in the altricial Australian pelican Pelecanus conspicillatus.

Quantitative methods have been used to correlate maximal oxygen uptake with lung development in Australian pelicans. These birds produce the largest altricial neonates and become some of the largest birds capable of flight. During post-hatching growth to adults, body mass increases by two orders of magnitude (from 88 g to 8.

Dynamics of leg muscle function in tammar wallabies (M. eugenii) during level versus incline hopping.

The goal of our study was to examine whether the in vivo force-length behavior, work and elastic energy savings of distal muscle-tendon units in the legs of tammar wallabies (Macropus eugenii) change during level versus incline hopping. To address this question, we obtained measurements of muscle activation (via electromyography), fascicle strain (via sonomicrometry) and muscle-tendon force (via tendon buckles) from the lateral gastrocnemius (LG) and plantaris (PL) muscles of tammar wallabies trained to hop on a level and an inclined (10 degrees, 17.4% grade) treadmill at two speeds (3.

Oxygen transport capacity in the air-breathing fish, Megalops cyprinoides: compensations for strenuous exercise.

Tarpon have high resting or routine hematocrits (Hct) (37.6+/-3.4%) and hemoglobin concentrations (120.

Respiration and energetics of embryonic development in a large altricial bird, the Australian pelican (Pelecanus conspicillatus).

We examined whether the previously reported low cost of embryonic development in pelicans could be attributed to a more efficient conversion of egg energy to hatchling tissues as a result of high initial egg water content, low embryonic metabolic rate and growth later in incubation than in more precocious species. We therefore determined egg and hatchling composition and the development of embryonic respiration in the Australian pelican Pelecanus conspicillatus, which lays one of the largest eggs (140-210 g) with an altricial developmental mode. The small yolk fraction (21%) is typical of all pelecaniforms; however, we found that intraspecific variability in fresh egg mass was related to water content (principally in the albumen), but independent of yolk mass (mean 13 g dry mass).

Ventilation and metabolism in a large semifossorial marsupial: the effect of graded hypoxia and hypercapnia.

Metabolic and ventilatory variables were measured in a large semifossorial marsupial, the hairy-nosed wombat (Lasiorhinus latifrons, 21.9 kg). In normoxia, the rate of oxygen consumption was 63% of that predicted for a similar-sized marsupial, and the level of ventilation (V(E)) was such that the convective requirement (V(E)/VO2) was similar to other mammals.

Comparison of the positive and negative ion electrospray mass spectra of some small peptides containing pyroglutamate.

The positive ion electrospray mass spectra of [M+H](+) and the negative ion electrospray mass spectra of [M-H](-) ions of selected pyroglutamate containing peptides both provide sequencing data. The negative ion spectra show the normal alpha and beta backbone cleavages in addition to delta and gamma backbone cleavages initiated by the side chains of Glu and Phe residues. For example, the [M-H](-) ion of pGlu Pro Gln Val Phe Val-NH(2) shows delta and gamma peaks at m/z 224 (delta, Gln3), 244 (gamma, Phe4), 451 (delta, Phe4), 471 (gamma, Gln3).

Postnatal development and control of the pulmonary surfactant system in the tammar wallaby Macropus eugenii.

Marsupials are born at an early stage of development and are adapted for future development inside the pouch. Whether the pulmonary surfactant system is fully established at this altricial stage is unknown. This study correlates the presence of surfactant proteins (SP-A, SP-B and SP-D), using immunohistochemistry, with the ex-utero development of the lung in the tammar wallaby Macropus eugenii and also investigates the control of phosphatidylcholine (PC) secretion from developing alveolar type II cells.

The influence of locomotion on air-sac pressures in little penguins.

Air-sac pressures have been reported to oscillate with wing beat in flying magpies and with foot paddling in diving ducks. We sought to determine the impact on air-sac pressure of wing beats during swimming and of the step cycle during walking in little penguins (Eudyptula minor). Fluctuations averaged 0.

Energetics of terrestrial locomotion of the platypus Ornithorhynchus anatinus.

The platypus Ornithorhynchus anatinus Shaw displays specializations in its limb structure for swimming that could negatively affect its terrestrial locomotion. Platypuses walked on a treadmill at speeds of 0.19-1.

Aquatic and terrestrial locomotory energetics in a toad and a turtle: a search for generalisations among ectotherms.

Murray short-necked turtles were trained to walk on a motorised treadmill and to swim in a recirculating flume. Through filmed records, the frequency of limb movement and the time that thrust was directed against the substrate were measured. The animals wore masks when walking and accessed air when swimming from a ventilated capsule placed on top of the water surface.

Energy, water balance and the roost microenvironment in three Australian cave-dwelling bats (Microchiroptera).

The ghost bat, Macroderma gigas, and the orange leaf-nosed bat, Rhinonycteris aurantius, occupy similar ranges across northern Australia and are often found in the same roost caves. Both species are considered rare and vulnerable to further population decline. A third small species, the large bent-wing bat, Miniopterus schreibersii, has a similar body mass to R.

Morphometric analysis of postnatal lung development in a marsupial: transmission electron microscopy.

Postnatal lung development in the tammar wallaby was investigated using transmission electron microscopy and stereological morphometry. Volume densities of interstitial, epithelial and endothelial tissue and capillaries in the parenchymal septa were measured as were surface densities of the airspaces and gas exchange capillaries. Absolute changes in these parameters were related to body mass.