The number of vets that recommend Puppy Kibble is 1000*.2=<<1000*.2=200>>200.
The number of vets that recommend Yummy Dog Kibble is 1000*.3=<<1000*.3=300>>300 vets.
Thus, 300-200=<<300-200=100>>100 more vets recommend Yummy Dog Kibble than Puppy Kibble.
#### 100