Currently Num Oi weighs 3.3 tonne up from 3 tonnes when she first conceived. Considering that the weight of the foetus, fluids and tissues associated with pregnancy weigh at least 200kg she is doing quite well keeping in shape.
By keeping she is thin it will make her birth easier. Keepers are achieving this through managing her diet and ensuring that she gets enough exercise.
It hasn’t been an easy road for Num Oi to get to this point as her baby’s father resides in Perth.
12 months ago an AI procedure was conducted by Dr Michael Lynch, Head Vet at Melbourne Zoo using sperm which was brought across from Perth Zoo by Dr Thomas Hildebrandt, a world-leading expert in elephant reproductive medicine.
This procedure was undertaken to bring the genes of Perth Zoo’s bull elephant, Putras Mas into the Australasian breeding program for this species. So far all of the elephants born as part of the program have been born to Melbourne Zoo bull Bong Su or Taronga Zoo’s bull Gung.
Timing was critical to the success of the procedure as Dr. Lynch explained, “we needed to perform the artificial insemination at just the right time, when Num-Oi was most fertile. Num-Oi ovulates once every 15 weeks, and like other Asian Elephant cows she is only fertile for a couple of days.”
“We monitored her cycle via blood tests, so we could time the procedure accurately.”
“Dr. Hildebrandt’s ultrasound examination revealed that she was just about to ovulate when the sperm delivery arrived. Because of the difficulties in maintaining the viability of the sperm sample during the trip from Perth to Melbourne, we were only cautiously optimistic that we had achieved a pregnancy,” he added.
When an ultrasound was performed by Dr. Lynch on November 11, 2014 the pregnancy was confirmed.
Photo Credit: Melbourne Zoo