The word should be 'killed' or 'murdered', not 'euthanised'. And why was this 'Trainer X' not named? Prosecuted? Shunned by their sport at the very least?
So maybe Greyhound racing doesn't have to be horrible but it lets itself be that way. Seems as good a reason as any to ban it. Now on to consider every other aspect of human-organised competition and moneymaking...

"It found that GRNZ had made significant progress reducing euthanasias, with 325 greyhounds being euthanised in the 2020/21 – 2021/22 seasons. 174 of these were euthanised at a single kennel belonging to 'Trainer X'. This licensed person was spoken with. Thereafter, that kennel only euthanised six greyhounds in the first two quarters of the 2022/23 season"
#GreyhoundRacing #Greyhound #HorribleHumans

https://en.wikipedia.org/wiki/Greyhound_racing_in_New_Zealand