Hello again and thanks for waiting.
I have worked out an answer for you below ...
1. It is unfortunately now too late to try and recover the cake by inducing vomiting as this should be done within the first hour after the cake was eaten, so all you can do is to sit things out. But thankfully I would not expect too much of a problem in most such cases.
2. The main this is that the cake did not contain any ingredients such as chocolate which can be toxic to dogs. What you can expect is that the dog will experience some degree of indigestion over the next five or six hours and have a bloated sleepy feeling, after that a mild transient bout of vomiting and / or diarrhoea may occur.
3. What to do is just to monitor your dog for present, starve her for the next 12 hours but make sure she has access to water and then keep her on small light frequent meals for a couple of days. Of course if any odd symptoms do set in then have her checked over by an ER vet without delay, however most dogs will be just fine.
I hope I have covered your question fully enough but if you would like further clarification or to talk things over a bit more then I will be on-line for the next hour or so and I will be more than pleased to continue working with you.
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