Good luck trying to get any of the subsidized aid with your parent's information on the FAFSA. My Dad is a doctor and he contributed NOTHING to my college education, however I still had to put his income on my FAFSA.
This is 100% not true for government Stafford loans at US veterinary schools.
You have to put down your parents info for some loans (HPSL, possibly some school based loans). But by going to graduate school you are automatically considered financially independent, even if you don't meet any of the other requirements for financial independence. So even if your parents' info is there for other purposes, they DO NOT factor it into your Stafford loan/federal direct loan calculations.
Anyway, when I went into the financial aide office at ISU to see about getting out of putting his info on my FAFSA they told me that the only way to do that was to be over 24 years of age, married, a child of the foster care system, or a refugee. I was none of those and was stuck with his income on my forms. I only qualified for unsubsidized and private (really high interest rate) loans. Yeah, I'll be paying off student loans till I die. Thanks Dad!
If ISU is Iowa State University, then this information must have come from being an undergraduate there or something, because when I was there last year, the financial aid officer told us the complete opposite thing for veterinary students.
What's more, I put my parents' info on my FAFSA last year (for veterinary school) because I wasn't sure which school I'd end up at and some of them did have HPSLs. My parents are do very very nicely (financially) and would easily disqualify me for any nice government subsidized loans if the government figured that they were contributing to my education. However, since the gov't doen't use parental info for determining your Stafford loan sub/unsub breakdown in grad school, it made no difference. I got the full $8,500 subsidized that grad students can get and was also offered the full $30,000 (or there abouts) unsubsidized that all medical grad students get offered regardless of financial circumstances.
Stafford loans are currently 6.8% fixed interest rate (though I believe it's up for adjustment every July 1), so definitely not a high interest loan. Although, sadly, much higher than they used to be maybe 10 years ago (3-ish% interest, so I've heard).