First of all, that's way too many food changes for a 4 month old puppy. Changing food requires a slow transition to prevent digestive upset.
Slow transition to the new food is as follows to prevent diarrhea. If at any time during the transition, the pup has diarrhea return to previous amounts of food per feeding.
Amount per feeding:
Day 1-4 ¾ cup of old food and ¼ cup of new food.
Day 5-9 ½ cup of old food and ½ cup of new food.
Day 10-14 ¾ cup of new food and ¼ cup of old food
Day 15 Start 100% of new food
Generally, mastiffs are allergic to grain and chicken found in kibble. There are a number of posts on the forum regarding kibble for your new pup. Do a search for food to check them out.
You can check
www.dogfoodadvisor.com and
www.dogfoodanalysis.com On this forum, Smart_Family is our resident food guru.
http://healthypets.mercola.com/sites/healthypets/archive/2013/05/31/large-dog-feeding-mistakes.aspx
You may want to check out the raw diet for your pup. You may want to check out the raw diet for your pup. Check out the raw diet section of the forum which has a wealth of information.
Check out Dr. Becker’s videos on youtube.com for a lot of great information regarding the raw diet. It’s a 3 part series with a wealth of information.
[video=youtube;Qx2YIIpF4cc]http://www.youtube.com/watch?v=Qx2YIIpF4cc[/video]
Continue on rick and chicken for a few days to reset the system and then start with a new food.