There's a whole scoring point scheme. I honestly don't know what the breakdown is though, I just remember seeing my numerical score at some point in my paperwork. So.. anything could be important?
GPA, essays, letters of rec, overall experience (work or volunteer) probably the most important. My vet school is P/F only so they wouldn't have been able to evaluate vet school GPA for me.
I didn't list any research on my application, but I feel like that would get coded as part of your overall work experience. Certainly won't hurt, especially if it's in something related to what they do.
I don't think I listed much in the way of extracurriculars really because I don't do much outside of school and work. I am a second career student so I have years of work experience to show things like leadership or what have you. (I do some volunteering for things I care about or am interested in, but I'm not particularly active in any clubs, for example.) I do have a lot of government experience specifically because almost all of my work experience was for the government before vet school.
Clinical experience... I also don't really have any of that. (Now I'm starting to wonder how I got into vet school let alone got this scholarship.
)
I think having large animal / herd / population medicine / infectious disease experience in any capacity is helpful for getting any USDA job. I had two USDA internships (FSIS and APHIS) and volunteer experience with state veterinary programs before applying. It was probably pretty clear based on my resume and essays that this is a career that I want for the long haul, and didn't apply just for the scholarship money. I'm also a dual DVM/MPH, and the MPH part is helpful too I think.