General Tips

Tools — the most useful dissection tool is a blunt probe. It will separate tissues easily along natural cleavage lines, without damaging the structures being studied. If cutting is necessary, a scissors is the best choice, because it will only cut between the blades. Razor blades and scalpels are almost totally unnecessary, and of course are a danger both to the specimen and the people doing the dissection. In fact, in our lab, we no longer distribute razor blades or scalpels with the dissection kits. A scalpel can be used to nick the skin to provide access for a scissors. Once that is done, there is really no need to ever again use any instrument more dangerous than a scissors. In order to dispense with the razor blade and scalpel, it probably helps to have small, sharp, fine pointed scissors. See p. 10 of the FPDG (Fetal Pig Dissection Guide).

Speed & Caution — Look at the pictures and read directions carefully. The FPDG is deliberately designed so that the text describing a structure can be read without turning away from the page with the illustration of the structure. Once you have read the directions, ask questions if any seem obvious. Otherwise, go to it! Occasional mistakes are inevitable, and part of the learning
process. If you make a mistake, you can always ask to see other specimens for better examples of structures. In the case of paired structures, you may want to look on the other side of your specimen.

Look at other specimens — Even if your dissection goes well, look at other pigs regularly. No two pigs will look exactly alike. This is partly due to differences in dissection technique, but mostly due to natural variation in the structures of two different animals of the same species. This is the way animals are in the real world! Surgeons can’t count on the renal arteries always having exactly the same structure, so they do diagnostic tests before attempting a kidney transplant. Different fetal pigs are the same; small differences
in structures are very common, large differences are not unusual. In addition, if you are tested by way of practical tests, you will need to be able to recognize a structure in whatever animal is used on the test. Once you have seen a structure in several animals, you should have no difficulty in recognizing a good example of it in any specimen.

Anomalies — minor internal malformations are very common in fetal pigs, as is the case with most mammals. Actually
it would probably be more accurate to call them developmental variations instead of malformations, since most of these variations would be perfectly normal functionally. The most common developmental variations are in the blood vessels, especially the veins. Splitting of the abdominal vena cava is a common example. It arises from the failure of the cardinal veins to completely fuse.

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