Experimental Long-Term Conservation of an Infant-Sized Piglet—Efficacy of a Late 17th Century Embalming Procedure

In this experiment, we used a late 17th century embalming protocol for the long-term preservation (7.2 years) of an infant-sized piglet in order to evaluate the success of this technique over a period of several years. According to the description of the French anatomist Penicher (published in 1699), an 8.8 kg female piglet corpse was treated with a broad spectrum of herbs, seeds, leaves, flowers and dried berries, along with an alcohol-based fluid following subtotal exenteration and a reduction in peripheral muscle mass. The further process of this dry embalming technique was monitored by visual, tactile and olfactory evaluation of the embalmed body, along with a record of the body weight. Repeatedly taking samples from the skin and soft tissues provided insight into eventual changes on a histomorphological level and two whole-body CT scans complemented the evaluation of the internal changes within the corpse, which was eventually examined at autopsy. On the macroscopic level, we recorded slight signs of autolysis and very mild putrefaction within the first few weeks and a very well preserved and stable body over the subsequent years of evaluation. In parallel, we noted a gradual loss of fluid, as shown by a reduction in the body weight. This occurred faster in the first year (reduction in body weight by ca. 25%) than in the following ca. 4 years (with another ca. 25% loss of body weight). The CT scans showed stable osseous and soft tissue structures, while the few remaining internal organs that had been left inside the body after initial evisceration (such as kidneys and internal genitalia) had already completely disappeared after approx. 1 year. On the histological level, the histoanatomy of skin, subcutis and muscle remained intact over the entire observation period. A loss of epidermal cell nuclei was not noted before day 1772 and there were only slight signs of adipocire formation of fat tissue at the end point of observation (day 2634). In summary, we can confirm that excellent body preservation of external skin and soft tissue was maintained over a considerably long period (in this case, 7.2 years) using the applied protocol of dry embalming, but a complete loss of residual internal organs/structures beyond skin, subcutaneous fat tissue and muscle. Previous observations of the excellent preservation of an infant mummy that underwent the dry embalming procedure are very plausible.