SEGAR VETERINARY HOSPITAL
No.2, Jln Manis 3, Tmn Segar, Cheras, 561000 KL
Tel: 03-91302059; 91304641; 91332343
Mon-Sat 9am-9pm, Sun&Public holidays 9am-5pm

they have night emergency service too but you must call and be there while waiting for the doctor to arrive. Night Emergency number: 03-91317839/012-3817003

I recommend Dr. Chee, he's a well experienced & friendly vet and normally you are expected to wait because he often deals with pets' surgeries.