Preliminary study on the estimation of the time of death in animals based on microflora development in a dog’s gastrocnemius muscle

Determination of the exact time of death of a human being or animal is extremely important for investigations conducted by law enforcement agencies. The development of a single model of tests and analysis of the site of the incident would be a breakthrough for forensic and veterinary medicine in estimating the exact time of death. Microorganisms play a key role in the putrefaction process. Each stage of decomposition is characterized by the colonization of tissues by different microbial taxa. The objective of the study was to determine the suitability of microbiological tests for establishing the time of death, using the example of the gastrocnemius muscle in a dog (German Shepherd). The results of the study showed that sporulating aerobic bacteria of the species Bacillus cereus, as well as anaerobic bacteria, played a major role in the putrefaction process. No E. coli were found in the material. The first bacterial colonies belonging to the Bacillus cereus group were observed on the 7th day after the death of the animal, and their quantitative growth persisted throughout the study period, i.e. until the 21st day after death. The analysis carried out in this study shows that Bacillus cereus bacteria appear much sooner than anaerobic bacteria.