... affects foraging behaviour in a colonial waterbird, the black-headed gull, Chroicocephalus ridibundus . First, a validation of phenylhydrazine (PHZ) treatment in gulls revealed a 9–18% reduction in haematocrit and blood haemoglobin concentration (via oxidative denaturation and haemolysis of erythrocytes...

...) on captive house sparrows in order to investigate the consequences of short-term dehydration on baseline and stress-induced corticosterone levels. As expected, water-deprived birds displayed higher plasma osmolality and haematocrit. Additionally, water-deprived birds had lower defecation rates, suggesting...

... data on bald notothens ( Davison et al., 1988 ; Franklin et al., 1993 ). As expected, the haematocrit in sham-operated fish was substantially higher than that of splenectomized fish following a period of enforced exercise (∼26% versus ∼15%). Consequently, the blood oxygen carrying capacity...

..., the European starling ( Sturnus vulgaris ). We show that changes in haematocrit, body mass and wing length are independent of year and brood quality, while changes in haemoglobin concentration are higher in low-quality broods. Moreover, we also identify higher oxidative stress in low-quality year and second...

... not show post-training differences in sprint speed. Although acclimation to the laboratory environment and training explain some of our results, mechanistic explanations for these results correspond with the observed performance differences. After training, endurance-trained lizards had higher haematocrit...

...Tobias Wang; Sjannie Lefevre; Nina K. Iversen; Inge Findorf; Rasmus Buchanan; David J. McKenzie To address how the capacity for oxygen transport influences tolerance of acute warming in fishes, we investigated whether a reduction in haematocrit, by means of intra-peritoneal injection...

...Magali Petit; François Vézina In small resident bird species living at northern latitudes, winter cold acclimatization is associated with an increase in pectoral muscle size and haematocrit level, and this is thought to drive the seasonal increase in summit metabolic rate ( Ṁ sum , a measure...

... 3 4 2002 © The Company of Biologists Limited 2002 2002 hypoxia heart salamander Ambystoma tigrinum cardiac output haematocrit hypometabolism cytochrome oxidase elongation factor 2 representational difference analysis Tiger salamanders ( Ambystoma tigrinum ) inhabit...

... %; means ± s.d .) over the duration of the experiment. Pups less than 5 days of age had an elevated haematocrit and reduced plasma volume compared with older pups. Although plasma volume and blood volume increased, mass-specific blood oxygen stores (total haemoglobin) fell during the study period...

... capillary blood volume and a remarkably extensive alveolar surface area in certain species developed in a remarkably large lung. These factors were augmented by, for example, exceptionally high venous haematocrits and haemoglobin concentrations. In birds, a particularly large respiratory surface area...

... lactate rainbow trout Oncorhynchus mykiss swimming endurance muscle fatigue P ao 2 haematocrit Migratory fish species such as trout can swim for months without rest (e.g. Davie et al . 1986 ), and other species such as tuna are actually dependent on continuous swimming...

... a significant, uniformly lower CS activity (by 60–83 %) as a result of a lower mitochondrial fractional volume. Haematocrit and capillary-to-fibre ratio in the pectoralis were also significantly lower in hypothyroid birds, and skeletal growth and plumage development were affected. * Author...

... internal oxygen consumption (total – gill ). Following exercise training, haematocrit (Hct) in the HS group (27.1%) was significantly higher than in the LS group (23.3%). However, neither the maximum nor U crit was significantly different in the two groups. q IA was inversely related to Hct but, in spite...

... and the circulatory system must be able to meet this demand. Exercise at a speed great enough to cause exhaustion results in an elevation in haematocrit (Hct), which can increase the oxygen content of the blood. The magnitude of the Hct increase varies among different species of fish, although generally the increase...

...P. Gallaugher; M. Axelsson; A. P. Farrell ABSTRACT Haematological variables were measured during aerobic swimming (45–55% of U crit ) and at critical swimming velocity ( U crit ) in acutely splenectomized and sham-operated rainbow trout. There was no correlation between haematocrit (Hct) and U crit...

... ), it follows that blood flow rates will also be lower. One might therefore predict that the relatively low haematocrits in hagfish ( Johansen et al . 1962 ; Forster et al . 1989 ) and lack of plasma albumins ( Manwell, 1963 ) would maintain a relatively low blood viscosity at low flow rates when blood tends...