CVA Laboratory Sample Handling 5

Question 1

A skin scraping is collected to evaluate for which condition?

Accepted Answer

Mange mites (Demodex or Sarcoptes)

Answer

Deep skin scrapings are the primary diagnostic method for detecting demodectic and sarcoptic mange mites by scraping until capillary bleeding occurs.

Question 2

What is the purpose of adding formalin to a tissue biopsy sample?

Accepted Answer

To fix and preserve tissue architecture for histopathology

Answer

10% neutral buffered formalin crosslinks proteins, halting autolysis and preserving tissue morphology for histopathological examination.

Question 3

Which of the following is an appropriate container for submitting a tissue sample for bacterial culture?

Accepted Answer

Sterile culturette swab or sterile container without additives

Answer

Tissue for culture must be placed in a sterile container without fixatives, as formalin or other preservatives will kill bacteria and prevent growth.

Question 4

When handling a sample labeled as 'biohazardous,' what should the veterinary assistant do?

Accepted Answer

Wear gloves and handle according to facility biosafety protocols

Answer

Biohazardous samples must be handled using appropriate PPE (gloves, eye protection) and facility-specific biosafety protocols to protect staff.

Question 5

How long can a whole blood sample in an EDTA tube typically be stored at room temperature before CBC results become unreliable?

Accepted Answer

Up to 4 hours

Answer

EDTA whole blood is most reliable when analyzed within 4 hours at room temperature; prolonged storage causes cell swelling and morphological changes.

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