You can keep the bag open and maintain freshness up to the best-before date, provided you store it folded down in a cool, dark place as per the instructions on the back of the pack.
Note: This article refers specifically to the change in Barking Heads dog food range in October 2023, when new dry dog food products were introduced to replace and update the previous range. The new dry dog food products can be identified by looking for the 'Made in the UK' symbol on the packaging.