Hematocrit is related to age but not to nutritional condition in greater flamingo chicks

We measured the hematocrit from greater flamingo chicks Phoenicopterus roseus over 4 years to test whether this blood parameter was related to the nutritional condition of chicks, as there are controversial results on whether hematocrit may be used as an index of body condition. We also tested whether hematocrit increased with chick age, as there would be an age-related increase of oxygen demand due to exercising. We found no evidences that hematocrit was related neither to the nutritional nor to the body condition of chicks. Hematocrit increased with chick age, which may be related to the increased requirements of chicks for oxygen delivery during development.