An initial study of insect succession on pig carcasses in open pastures in the northwest of Uruguay

Forensic Sci Int. 2019 Sep:302:109837. doi: 10.1016/j.forsciint.2019.05.053. Epub 2019 Jun 22.

Abstract

The succession of carrion fauna and the decomposition stages were studied in summer for two years in open pastures of the Department of Paysandú, Uruguay (32°21'5″S; 58°3'37″). Each year, three pig carcasses (Sus scrofa) were placed in wire mesh cages, 100 m apart from each other. Each carcass was surrounded by pitfall traps, and a modified Malaise trap was placed above. Daily samplings were carried out to collect the insects present in the carcasses and the traps, and body and environmental temperatures were measured. The composition of carrion entomofauna and the decomposition patterns were markedly similar in both sampling years. The decomposition process was rapid, that is, the time to reach the remains stage was 7 days in all treatments, both years. The mosaic nature of decomposition was observed. Both Chrysomya albiceps (Wiedemann) and Cochliomyia macellaria (Fabricius) behaved as primary invaders of the carcasses, although the former species and its larvae were dominant. The first adult blow flies emerged after 6 days. The remains stage was characterized mainly by both adults and larvae of Dermestes maculatus. This preliminary study represents the first contribution to the knowledge of cadaveric succession in Uruguay. Its seasonal replication supports the succession pattern obtained.

Keywords: Chrysomya; Cochliomyia; Dermestes; Forensic entomology; Paysandú; Sus scrofa.

MeSH terms

  • Animals
  • Coleoptera / physiology*
  • Diptera / physiology*
  • Feeding Behavior / physiology*
  • Forensic Entomology*
  • Humidity
  • Larva / physiology
  • Postmortem Changes*
  • Swine
  • Temperature
  • Uruguay