Page 62 - The Veterinary Laboratory and Field Manual 3rd Edition

Setting up and using a laboratory service 31

Figure 1.28 The approach to a post-mortem may differ depending on whether one or many animals have
died from a disease. In some cases, sick live animals (Figure 1.29) may need to be euthanized to provide
fresh material for laboratory tests. This approach may save other animals and, if the animal cannot be
treated, may be considered more humane than leaving it to die (it should be noted, however, that in some
cultures this may not be permitted for religious reasons). If an animal is found dead and the carcass is
still reasonably fresh a full post-mortem (PM) or necropsy can provide a lot of valuable information. If the
carcass has already begun to rot then a quick PM may still be worthwhile but it may not be worth trying to
collect a lot of samples. The procedure for performing a PM is outlined in Chapter 8. A simple post-mortem
kit is outlined in Table 1.4. Practical limitations as well as expense will often dictate the range of samples
taken but usually (unless the cause of death is obvious) the following will be collected: (1) Tissues (healthy
and diseased) from the main organ system (lungs, heart, liver, kidney etc.) and tissues demonstrating spe-
cific lesions (that is, abscesses, vesicles, ulcers and so on) will be collected and preserved for histological
examination (see Chapter 8). (2) Swabs of fluids from lesions and/or tissue samples may be collected for
microbiological examination (see Chapter 4). (3) Parasitic organisms (internal and external) (see Chapter
3). (4) Blood may be collected for culture. If anthrax is suspected then you should not open the carcass
(see Chapter 4). (5) Specific samples may be collected for specific diagnoses, that is, rumen contents for
suspected poisoning (see Chapter 7). (6) Blood/tissue smears for cytology (see Chapter 8). (7) Urine/eye
fluid for microbiology (see Chapter 4). Detailed notes should be kept throughout the procedure to describe
any abnormalities found during the post-mortem (see post-mortem submission in Appendix A2).

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