The world's oldest animal marriage looks set to have turtley ended after an incredible 115 years when the two Giant Turtles at an Austrian zoo refused to share their cage anymore.Zoo management have called in animal experts to try and give the pair counselling - feeding them romantic good mood food and trying to get them to join in joint games - but so far without effect.Zoo boss Helga Happ said: "We get the feeling they can't stand the sight of each other anymore."Bibi and Poldi have been a pair since before anyone alive today can remember - they have been together at the Austrian zoo in Klagenfurt for 36 years and before that they lived at Basel zoo in Switzerland.Happ added: "They are both 115 years old - they have been together since they were young and grew up together, eventually becoming a pair."But for no reason that anyone can discover they seem to have fallen out, they just can't stand each other."Zoo staff realized the pair had fallen out after Bibi attacked her partner - biting off a chunk of his shell - and then carrying out several further attacks until he was moved to another enclosure.Although they have no teeth Giant Turtles have a horn rimmed mouth and powerful jaws that are a potent weapon when they want to cause damage. Each of the 100 kilo animals has the ability to kill the other if they wanted.Zoo staff have told the experts that nothing has changed in the pair's routine - but Bibi in particular wanted to have the cage to herself and be a single.Happ added: "We have staff talking to and trying to engage the two in interacting, and we hope that they might find their harmony again."We were told that it's very rare that after so many years animals who are a pair will fall apart, but that's where we are. We hope though we can bring round a reconciliation."