CINCINNATI, OH (October 5, 2010) - Anticipation is mounting behind the scenes at the Cincinnati Zoo & Botanical Garden, where the 18-year-old pregnant Indian rhinoceros, “Nikki,” is expected to give birth any day.
Not only will this be the world’s first birth of an endangered Indian rhino conceived by artificial insemination (AI), but it will also be the world’s first Indian rhino produced with frozen-thawed sperm. The father, “Vinu”, is a 38-year-old male Indian rhino at the Bronx Zoo - the two have never met.
The Cincinnati Zoo’s Animal Care Staff have been busy “baby proofing” the indoor and outdoor rhino exhibit to prepare for the birth. Last week, a dedicated team of 58 Zoo Volunteer Observers (ZVO’s) began the overnight watch program, using remote television monitors set up in the Conservation and Research of Endangered Wildlife (CREW) facility. Starting at 3 p.m. to 7 a.m. each day, teams of two volunteer observers take four to five hour shifts watching Nikki to look for behavioral changes that might indicate labor.
“With the volunteer observers here, the anticipation is really starting to build. We are more than excited to welcome Nikki’s calf into the world,” said Dr. Monica Stoops, Reproductive Physiologist at CREW, at the Cincinnati Zoo. “The Zoo is buzzing, not only because of the significant scientific achievement this calf represents, but also because of the exciting new addition to our Zoo family.”
Three years ago, Nikki was the first endangered rhino to become pregnant through artificial insemination of frozen-thawed sperm. Unfortunately, after completing a full term pregnancy, Nikki delivered a stillborn calf. Approximately 50% of Indian rhinos that become first time mothers over the age of 10, like Nikki had been, experience a stillbirth. Despite the devastating outcome, Dr. Stoops and her team looked to the future and were comforted by the fact that female Indian rhinos experiencing a stillbirth following their first pregnancy have successful live births with subsequent pregnancies.
Nikki’s pregnancy is important not only for the captive population of Indian rhinos, but for the fact it demonstrates the science of AI using frozen-thawed sperm that was developed by CREW Scientists is a repeatable and valuable tool to help manage the captive Indian rhino population. With only 60 Indian rhinos in captivity in North America and approximately 2,500 remaining in the wild, successful breeding between rhino pairs is important to maintain the genetic diversity necessary to keep a population healthy and self-sustaining. Unfortunately, natural breeding attempts in captive Indian rhinos frequently result in severe aggression between the male and female. Because of this behavioral incompatibility, genetic management of the Indian rhino is a challenge. Artificial insemination can be used to improve the genetic health of captive Indian rhinos by infusing genes from non- or under-represented rhinos.
The heart of the Cincinnati Zoo’s CREW, both for its Animal and Plant Research Divisions, is the CryoBioBank. This genomic resource bank consists of thousands of cryopreserved tissues from over 75 animal species and over 135 plant species that are conserved for future use. CREW scientists have expanded upon this effort by creating a genome resource bank specifically for male Indian rhinos. Collecting and banking sperm from genetically valuable male Indian rhinos is an important step toward prolonging the genetic life of founder animals and preserving the genetic potential of males that may otherwise never contribute to the captive population. Over the past eight years, CREW scientists have refined semen collection in the rhino and developed a successful method of freezing rhino sperm. Using this technology, CREW scientists have collected sperm from the top genetically valuable male Indian rhinos from zoological institutions throughout North America.
Rhinos once ranged over large parts of Africa, the Middle East and southern Asia. Of the five living rhino species, the Indian rhino is the second largest, weighing in at up to 6,000 pounds. It primarily inhabits the floodplain grasslands of northern India and southern Nepal.
Poaching of wild Indian rhinos in Nepal and India has been on the rise over the past five years. Rhino horns are sold on the black market, as an ingredient in traditional Chinese medicines or as dagger handles in Yemen and Oman. Laws banning the use of rhino horn have helped, yet poaching and smuggling still persists. Continued protection and law enforcement will be necessary for their survival.x
The Cincinnati Zoo is world renowned for welcoming significant rhino calves into the world with the birth of three critically endangered Sumatran rhino calves since 2001. This birth, of an endangered Indian rhino, will mark another first for the Cincinnati Zoo.