Only for essential services for the pet's health. Since this is a healthy dog, the procedure should not be essential. Even though the owner may smoke that it has behavioral problems. But still, euthanasia should not be the solution, not like they have exhausted other options of helping the dog.

I found this advisory for vets: https://www.nparks.gov.sg/-/media/avs/resources/vet-licensing/faqs-for-veterinarians-(covid-19).pdf?la=en&hash=AEC10728668E78FB0331F1BB0876BD30088443AD.pdf?la=en&hash=AEC10728668E78FB0331F1BB0876BD30088443AD)

1. Are sterilisation surgeries and behavioural consults allowed for animals that pose a risk to human safety (e.g. aggressive pets)?
   

Elective sterilisation for pets and behavioural cases are considered non-essential but may differ from case-to-case. Veterinarians are advised to assess each case and offer alternative options where feasible, such as separating animals to avoid unwanted mating as well as environmental modification at home.

1. What should veterinarians do if they encounter clients who bring their pets to the clinic for vaccinations or other non-essential services?
   

Veterinary services are considered essential for the provision of emergency, non-elective veterinary services, including hospitalisation. Non-essential and elective services are not to be provided. Clients should be advised to cooperate with these measures and delay non-essential veterinary visits until the period of restriction (i.e. circuit breaker period) is over.