Yup, Penny went on strike at breakfast when she was about this age. I mixed her supper with salmon oil, but she refused to eat the plain kibble. In the end I started giving her Nature Diet at breakfast which she woofed up. I admit to being an anxious cocker mummy because she was already quite small for her age.
The combination has worked well and she now cleans her bowl every time, and at one year old weighs a respectable 10kg.