<P> Fetal pigs are unborn pigs used in elementary as well as advanced biology classes as objects for dissection . Pigs, as a mammalian species, provide a good specimen for the study of physiological systems and processes due to the similarities between many pig and human organs . </P> <P> Along with frogs and earthworms, fetal pigs are among the most common animals used in classroom dissection . There are several reasons for this, the main reason being that pigs, like humans, are mammals . Shared traits include common hair, mammary glands, live birth, similar organ systems, metabolic levels, and basic body form . They also allow for the study of fetal circulation, which differs from that of an adult . Secondly, fetal pigs are easy to obtain because they are by - products of the pork industry . Fetal pigs are the unborn piglets of sows that were killed by the meat packing industry . These pigs are not bred and killed for this purpose, but are extracted from the deceased sow's uterus . Fetal pigs not used in classroom dissections are often used in fertilizer or simply discarded . Thirdly, fetal pigs are cheap, which is an essential component for dissection use by schools . They can be ordered for a little more than $25 at biological product companies . Fourthly, fetal pigs are easy to dissect because of their soft tissue and incompletely developed bones that are still made of cartilage . In addition, they are relatively large with well - developed organs that are easily visible . As long as the pork industry exists, fetal pigs will be relatively abundant, making them the prime choice for classroom dissections . </P>

Where do fetal pigs for dissection come from
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