Dogs that eat the same food for months or years develop gut bacteria tuned to that specific diet. Change the food abruptly and those bacteria are not prepared. The result: soft stools, gas, and an unhappy dog for a week or two.
This is entirely avoidable with a gradual transition. It is also easier than cleaning up the alternative.
The 10-Day Method
This is the standard approach recommended by most vets. The percentages are guides, not laws:
- Days 1-2: 75% old food, 25% new food
- Days 3-4: 50% old food, 50% new food
- Days 5-6: 25% old food, 75% new food
- Days 7-10: 100% new food
If your dog has a sensitive stomach, extend this to 14 days and move more slowly through each stage. There is no prize for transitioning faster.
What to Watch For During the Switch
Some loose stools in the first few days are normal. Mild flatulence is normal. Loss of appetite for a day while they adjust to the new flavour is also normal.
What is not normal and warrants slowing down or stopping:
- Vomiting that continues beyond the first day
- Complete refusal to eat for more than 48 hours
- Blood in stool
- Significant lethargy beyond what you would expect from an upset stomach
Picky Dogs and the Transition
Some dogs resist new food on principle. If your dog eats the old food out of the bowl and leaves the new, try mixing more thoroughly so they cannot sort through it. You can also add a small amount of warm water to the new food to intensify the smell and make it more appealing.
Do not be tempted to switch back at the first sign of resistance. A healthy dog will eat when hungry. Give the transition time before concluding it is not working.
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