Relationships of foetal haemoglobin level to age of newborn fallow deer (Dama dama)

Abstract

The relative proportions of foetal and adult haemoglobins were quantified by densitometry of isoelectric focusing patterns in blood samples from 157 fawns from a free-living population of fallow deer (Dama dama) in Coto Doñana National Park, southwestern Spain. During the first week of life, the ratio of adult to foetal haemoglobin concentration increases with age. The proportion of foetal haemoglobin to total haemoglobin in peripheral blood proved a better indicator of age than morphological characteristics based on the persistence of natal traits in the fawns external phenotype. The erythrocytes of even the youngest fawns contained some adult haemoglobin, the mean percentage of adult haemoglobin in offspring less than 24 h of age being 13.7% in the reproductive season of 1989 (n = 28) and 7.18% in 1990 (n = 25). Half of the fawns whose blood contained less than 3% adult haemoglobin failed to survive past the first weeks of life (even when body mass was not below average), whereas not a single fawn with more than 5% adult haemoglobin on its first day of life was subsequently found dead. Even when the effects of sexual dimorphism in body size are taken into account, the blood of male fawns contained less adult haemoglobin at a given age than that of females, as was evident from significantly lower levels of adult haemoglobin when referenced to several body size covariates such as body length, shoulder height, hind-foot length, and body weight.