Milk Composition in the Grey-headed Flying-fox, Pteropus poliocephalus (Pteropodidae : Chiroptera)

Abstract

Milk samples from 11 captive flying-foxes were collected at various times during lactation from 5 to 139 days post partum and analysed for protein, carbohydrate, total solids and ash. In addition, samples from 14 free-living animals, collected on a single occasion, were analysed. No significant changes in milk composition were observed during lactation in the captive bats except for a small increase in protein and a small decrease in carbohydrate concentration late in lactation. The milk from captive bats contained less protein and total solids than that from free-living animals (mean values: protein, 2·59 and 3·64%, repectively; total solids, 11·1 and 12·7%, repectively) but there was no significant difference with repect to the carbohydrate (6·13 and 6·44%, respectively). The fat content, estimated from the total solids by difference, was low (1·9 and 2·2%, respectively) in both captive and free-living animals. The results are compared with previously published values for milk composition in Chiroptera and are discussed in the context of nursing behaviour and diet in captive and free-living flying-foxes.