Jim Cramer has always said that the humanization of pets is one of the greatest investing themes out there.
But he still didn't see it coming when privately held food giant Mars paid a huge premium for Veterinary Centers of America, known as VCA.
VCA shareholders received a 31 percent gain on Monday with Mars' $7.7 billion bid. Mars plans to pair the business with its Banfield pet hospital chain to create a dominant health care company for companion animals.
However, Cramer warned that this doesn't mean the rest of the pet players could have the same fortune.