Insect Succession and Decomposition Pattern on Pig Carrion During Warm and Cold Seasons in Kwazulu-Natal Province of South Africa

Abstract

With the aim of identifying insects with potential value as indicator species in postmortem interval (PMI), the location or season of death of human or monogastric animals, two medium-sized large white pigs were used for the study during cold and warm seasons. Five stages of decomposition and their durations were observed and described in the pig carcasses during both seasons. Carcasses were first colonized by flies from seven taxa during fresh stage. Chrysomya marginalis (Wiedemann) (Diptera: Calliphoridae), Chrysomya albiceps, (Wiedemann) (Diptera: Calliphoridae) and Musca domestica (Walker) (Diptera: Calliphoridae) were recorded as the overall dominant adult flies found on the carcasses in both seasons. Colonization by beetles began during the bloated stage in the warm season and active stage in the cold season. Dermestes maculatus (De Geer) (Coleoptera: Dermestidae) and Necrobia rufipes (De Geer) (Cleridae) were the most abundant beetles in both seasons. Flies and beetles were generally abundant during the warm seasons as compared to the cold season. However, the difference was only significant for beetles. The highest number of flies were recorded in the bloated stage for both seasons, however they were reduced in the active stage which coincided with the introduction of predatory beetles. The arrival time of the different arthropod species and their association with different stages of decomposition during both seasons pointed to their value in estimating the PMI in forensic investigations in the locality of KwaZulu-Natal, South Africa. Consequently, they can potentially be useful in the estimation of PMI and other cases of criminal investigations.

Molecular identification and diversity of adult arthropod carrion community collected from pig and sheep carcasses within the same locality during different stages of decomposition in the KwaZulu-Natal province of South Africa

“…Morphological identification based on the identification key described by ( Tourle, Downie & Villet, 2009 ; Iqbal et al, 2014 ; Lutz et al, 2018 ) classified collected dipteran flies into five genera; Chrysomya , Lucilia , Musca , Sarcophaga and one unidentified genus, and five Coleoptera families (Cleridae, Dermestidae, Silphidae, Scarabaeidae and Meloidae) ( Tembe, Malatji & Mukaratirwa, 2021 ; Tembe & Mukaratirwa, 2021 ).…”

“…The ecosystem of the farm is typically herbaceous due to long-term burning and it falls under the Southern Tall Grassveld ( Mills & Fey, 2004 ; Kiala, Odindi & Mutanga, 2017 ). Experiments were performed during the cold season (June–August 2019) and warm season (November 2019–January 2020) with measured temperature ranging between 18–19 °C and 21–23 °C respectively ( Tembe & Mukaratirwa, 2021 ).…”

“…Adult arthropods were cleaned by soaking them in distilled water for 10–15 min and air dried ( Tembe & Mukaratirwa, 2021 ). After drying, they were identified under a stereo microscope using identification keys based on body parts of the adult arthropods ( Byrd & Castner, 2001 ; Kolver, 2009 ; Iqbal et al, 2014 ; Lutz et al, 2018 ; Lubbe et al, 2019 ; BugGuide, 2020 ).…”

Degradative succession of the insects in small rodents in subtropical systems

“…Studies shows a high insect community variation, mainly by habitat differences (Parry et al, 2016), food availability (T. D. C. Moretti et al, 2008), insect community structure (Tembe & Mukaratirwa, 2021), and temporal changes (Richards et al, 2009). Studies in other regions have shown that Diptera and Coleoptera account for 60% of the fauna associated with decaying carcasses, and Chrysomya sp.…”

“…Studies in other regions have shown that Diptera and Coleoptera account for 60% of the fauna associated with decaying carcasses, and Chrysomya sp. are an important gender of scavenger fauna (Haskell et al, 2008;Oliveira-Costa, 2013;Tembe & Mukaratirwa, 2021). According to Moretti et al (2008), a higher diversity of arthropods has been found in cadaveric fauna, and Chrysomya megacephala (Fabricius, 1974) may be an important specie of scavenger fauna in southern Brazil (Carvalho & Mello-Patiu, 2008;Trivia & Carvalho, 2018).…”