Reproduction and Post-Natal Development of Hipposideros pomona Andersen, (1918) in Kyan Taing Aung Cave of Sagaing Hill Range within Myanmar

Abstract

Studies on sizes of animal at birth and on subsequent post-natal growth are important for understanding the aspects of their life history and for understanding a wide range of ecological, behavioural and developmental patterns. The study was conducted on a colony of Hipposideros pomona comprising approximately 700 individuals. The colony was located at Kyan Taing Aung Cave, a renovated seminatural structure situated at 21° 53.9' N, 95° 59.959' E and at an elevation of 165m above sea level on the Saging Hill Range, Myanmar and conducted from January 2005 to December 2006. Mating of H. pomona occured in the last week of October and parturition occurred during April and May. The gestation period was 180 days and the reproductive activity is associated with rainfall rather than the temperature. The pup appeared to be heavy with approximately 29.1 % of the adult female weight. The pups are assumed intermediate between precocial and altricial types. At birth the young bat was found to be already provided with canine teeth to grip not only the breast nipple but also the pubic nipple. The pattern of post-natal growth and development followed the basic trend of a linear growth of forearm and body mass during the preflight period. Linear regression conducted between the mean forearm length and mean body weight of both male and female growing pups was found to be highly significant. However, positive correlation was not established between the forearm length and the nature of the epiphyseal gap in the third metacarpal-phalangeal joint of the third digit. Hipposideros pomona attained sexual maturity at approximately seven months (210 days) from the time of birth, whence the forearm length had grown to approximately 40mm and the body mass attained approximately seven grammes.