There are several things you can do to help your pup bulk up:
Opt for high-calorie food.
More exercise can help build muscle but remember to increase the food portion size accordingly.
You may want to consider changing the feeding schedule, e.g., give your dog smaller portions, but more frequently.
Try to entice your dog by choosing tasty snacks or toppers such as wet food. Some pups are also fond of peanut butter! (as long as it's without Xylitol)
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