This used to be a common practice in hospital clinical laboratories, but laboratory professional organizations considered it to be highly unethical for a couple of reasons. First, that pricing scheme makes it impossible for clients to know exactly what they are being billed for. Worse than that, though, clients pay far different rates for the same services. Let’s assume, for example, that the vet routinely doubles the price that the lab charges. If a test costs $10, then the client is billed $20, which is a markup of $10. If a test costs $100, then the charge to the client is $200, and that client is paying $90 more than the first client for the same service (drawing blood and shipping the specimen to the reference lab).
I agree that the vet should be able to recover the cost of collecting and transporting specimens and make a reasonable profit for providing these services, but this should be billed separately. For example, the vet should have a separate charge for collecting blood or obtaining a biopsy specimen. Or, if not a separate charge, then add on a standard fee (a fixed amount and not a percentage of the reference lab’s price) for specimen collection, shipping, and handling to the actual cost of the test.
I disagree that the vet should mark up for interpreting the test. Interpretation of routine tests should be included in the cost of an office visit or farm call. After all, a primary care physician doesn’t charge for interpreting routine lab work–it’s included in the fee for the office visit. If a test is interpreted by another professional, such as a radiologist, then this should be billed separately.