REPRODUCTIVE PARAMETERS AND BIRTH STATISTICS FOR A HERD OF ASIAN ELEPHANTS ( ELEPHAS MAXIMUS) IN NORTH AMERICA OVER A 20-YEAR PERIOD.

Abstract

We reviewed medical records documenting 28 pregnancies occurring within a herd of Asian elephants ( Elephas maximus) over a 20-yr (1994-2014) period at a private facility in the southeastern United States. Twenty-six pregnancies resulted in live calves and two ended in stillbirths. The 26 live births represented the offspring of 11 cows and 5 bulls. Twenty-four calves survived their first year, including two critically ill calves born after dystocias. Male and female calves occurred in almost equal numbers. Mean duration of labor in this group was 36 hr although the median duration was 13 hr. Although oxytocin was administered to several cows, parturition did not always immediately ensue. Female fecundity ranged from 1-6 calves while female age at parturition ranged from 9-46 yr. Females delivered their first calves between 9 and 26 yr of age whereas bulls sired their first calves in their 20s, on average. The number of live births and the 93% calf survival rate are among the highest reported in any western hemisphere elephant-holding facility. This may reflect the intensive management of cows before, during, and after each pregnancy, the number of experienced multiparous cows, and the skill level of staff, most of whom had worked with each other and with this herd for many years. The data presented here may assist facilities planning to breed Asian elephants.