Postnatal growth and age estimation in the Indian false vampire bat (Megaderma lyra)

The Indian false vampire bat Megaderma lyra produces a single young under c aptive conditions, which is altricial at birth. Empirical growth curves wer e derived by measuring length of forearm, body mass and length of the total gap of the fourth metacarpal-phalangeal joint. Length of forearm and body mass followed a linear pattern of growth until day 28 and subsequently reac hed stability. The length of the total gap of the metacarpal-phalangeal joi nt initially showed a linear increase up to 4 days, followed by a linear de crease until 34 days when it closed. A quantitative method of estimation of age was derived from values of length of forearm and length of the total g ap of the fourth metacarpal-phalangeal joint during the preflight (first 28 days) and postflight stages, respectively. Width of the 95% confidence lev el was +/- 1.2 days at a mean length of forearm of 51.6 mm, and +/- 0.07 da ys at a mean length of the total gap of the fourth metacarpal-phalangeal jo int of 1.89 mm. Initiation of flight occurred 24 days after birth. At 28 da ys of age, young were able to forage on their own. There was no significant difference in the growth pattern of young held in captivity compared to th at of young grown under natural conditions.