What was Mrs.Pumphrey's last statement to Mr. Herriot? Did she know Tricki's real ailment?

Mrs. Pumphrey's last statement was, "This is a triumph of surgery." Mrs.Pumphrey was really happy to see that Tricki had fully recovered. She did not expect Tricki to recover within such a short period of time. However, she did not know Tricki's real ailment. She thought that it was only because of surgery.