About the time the Ladlows adopted their first greyhound an organisation called Greyhounds as Pets (GAP) started in New Zealand, with the aim of re-homing retired greyhounds.
Since the organisation started, 1000 greyhounds have been re-homed.
"Anyone who is starting out with greyhounds [as a pet] should get one from GAP," Mrs Laidlow said. "They do an excellent job."
Mr Ladlow said most greyhounds would start racing very young and would retire before they turned 5.
He said it was a shame so many were put down because they could live, on average, to about 15 years old.
"That was what really hit us - they do their best for you and their reward is, at 4 years old, to get their throats cut. That's not much of a reward really."
The Ladlows' four greyhounds are all named after Nordic gods including Saga, 13, Loki, 12, Freya, 7, and Thor, 4.
To find out more about adopting a retired greyhound visit www.greyhoundsaspets.org.nz.