From what I understand, it kind of depends on your financial situation/how you use your loans for living expenses for the year and how the trips are organized for the future.
This year the vet school was able to register the international trips as a part of "spring semester" and thus finances from spring semester (whether that be loans or scholarships, dependent on your financial situation) can be used to pay for the costs of the trip. This inclusion as a "spring semester class" also meant the trips were cheaper (maybe like $2500?), as they didn't include any fees for summer tuition. (But I also think that, if the trips weren't included as "spring semester," you could just save money from your loan for living expenses,etc. from fall/spring semester and use that instead of having to pay out of pocket for the trip).
This is the first year they were able to work them out this way, and they're hoping to do the same for the future, but they're not completely sure it will stay that way for the future (I really hope it does!). I don't think you can increase your loan amount in order the trip (maybe you could do that if it's a "summer semester" trip?), but asking Mercedes Serracin in the student affairs office could clarify this, as well as asking her about other scholarships/ways to fund international experiences (I know there was at least one for ~$1000 for this past year).