The University of Arizona

Arizona Veterinary Diagnostic Laboratory

Veterinary diagnostic laboratories are a useful aid in disease control for veterinarians and producers. The primary function of these laboratories is to provide assistance in disease diagnosis. They also serve as an "early warning" system for new emerging diseases, resurgence of well-known diseases, and introduction of foreign animal diseases into the United States. Finally, diagnostic laboratories may conduct applied research into animal diseases of local, state, national, and international significance.

The Arizona Veterinary Diagnostic Laboratory is home to several mutually supportive laboratory disciplines, including pathology, microbiology, immunology, and toxicology. The centralization of these disciplines in the same building aids in coordination of the diagnostic effort by the laboratory veterinarian. The laboratory veterinarian is experienced in the specialized field of diagnostic veterinary medicine, has the responsibility for interpretation of results from the various areas of the laboratory, compiles the results into a written report, and communicates the results to the owner or veterinarian. As a client of the diagnostic laboratory, you will be able to contact a laboratory veterinarian about the results of laboratory examinations rather than each of the individual lab areas.

Specimens received by the diagnostic laboratory with a request for diagnostic assistance are of many different types. We receive bodies of dead animals, sick animals that will be euthanized for necropsy, specimens from field necropsy examinations, surgical biopsy specimens, blood, urine, feed, water, milk, culture swabs, stomach contents, baits and other suspect toxic material. Upon arrival, the specimens are assigned a case number, which is used to track specimens through the laboratory. This number is also used for billing, report writing, and data retrieval. A completed "Request for Laboratory Examination" (see "SUBMISSION FORM" button on the HOME PAGE) should accompany every specimen. The important information to be included on the form includes the species, age, sex, reproductive history, herd size, number of animals affected, number dead, date of onset, clinical signs, treatment and vaccination history, and, if a field necropsy has been performed, gross lesions found. The laboratory veterinarian will use this information to select diagnostic tests necessary to arrive at a cause of the problem. The information is therefore essential to successful diagnosis.

Upon arrival, the specimen will generally be assigned to the laboratory veterinarian on duty for that particular day, unless otherwise requested. If the specimen is an animal for necropsy, he/she will perform the examination and collect specimens for distribution to the other sections of the laboratory as he/she deems necessary in order to arrive at a diagnosis based on (1) the necropsy findings, (2) the clinical history provided, (3) his/her knowledge of recent disease problems in the area, (4) past experience, and finally, (5) laboratory findings. Diagnostic laboratory veterinarians often take individual initiative in deciding which tests to perform based on past experience, and often will opt to perform tests not initially requested on the submission form. This tends to expedite the process of diagnosis and can prevent delays, which could be costly in lost production of animals. Many tests take days or weeks to obtain results.

The results of the laboratory findings are reported to owners or veterinarians, or both, depending upon your request. We prefer to report to an attending veterinarian. They possess the first hand knowledge of the clinical situation, environmental factors, and management practices that can be crucial in interpreting the findings and applying them in a field situation. Consideration of these factors in concert with laboratory findings is necessary to recommend control or treatment measures. In general, laboratory veterinarians refrain from recommending treatment. Phone reports are often given in cases that are urgent, such as rapidly spreading infectious diseases. All submissions are reported in written form at the completion of testing. These reports contain a lot of jargon that can be difficult for the layperson to translate into "plain English". We are always glad to provide a verbal interpretation to owners, but again, prefer that this be provided by the referring veterinarian who is best qualified to interpret the significance of the findings, specifically with regard to an individual’s animal or herd.