russell joyce schrieb:

Here is what you need to do to ensure a smooth transition to a new dog
food:
Day One: Start by mixing your old brand with the new brand in a ratio
of 3/4 to 1/4 - the smaller amount representing the new brand. Do this
for three days.
Day Four: After your dog has eaten the 3/4 to 1/4 mixture for three
days, graduate to half and half for another three days.
Day Eight: For the last three days, go to a 3/4 to 1/4 mixture, only
this time the smaller amount is the old brand of food.
By the end of the 12 days, your dog should be ready to eat the new
food on its own.

Alternatively, you could avoid this kind of human-made problem from the
outset by feeding a variety of food.

Sally