Food changes during pregnancy

We have 2 Irish Wolfhounds who aren't directly related. They are 2 days apart and are 9 and 11 days before their first birthday.  I did not expect her to be in heat at such a young age, but here we are.  I know she could be pregnant and want to know if I need to change her diet.  Their "mush" is usually a mix of 60% chicken back and neck and 40% mix of Carrot, broccoli, spinach and celery.  I often add some type of oil (Salmon and/or a mix of olive, coconut and garlic) and egg including shell.  The "mush" is about 30% of their diet (about a pound each) and then chicken leg quarters for the remainder.  They weigh about 135 for the dog and 120 for the bitch.
Can someone help me understand what I need to do or change during pregnancy.  They haven't eaten a processed meal since they were 9 weeks old.
Thank you in advance for any help and/or questions
Ken