INSECT-MEDIATED DECOMPOSITION OF BURIED AND UNBURIED REMAINS FOR POSTMORTEM INTERVAL DETERMINATION IN DIFFERENT SEASONS UNDER TEMPERATE SLOVENIAN CONDITIONS
DOI:
https://doi.org/10.26873/SVR-2335-2026Keywords:
postmortem, entomology, insect, Slovenia, forensicAbstract
Forensic entomology is an increasingly important tool in veterinary forensic investigations, particularly in cases of suspected animal abuse, which is classified as a criminal offence under Article 341 of the Slovenian Criminal Code. Reliable estimation of the postmortem interval (PMI) is essential in such cases; however, region-specific forensic entomology data for Slovenia have been lacking. This study investigated the effects of season and burial on insect colonisation, larval development, and decomposition under natural conditions in a temperate Slovenian environment. Hind limbs from 40 pigs (Sus scrofa domestica), were studied across four seasons (autumn 2022 to summer 2023). In each season, paired limbs were either left exposed on the ground surface or buried at a depth of 50 cm. No insect activity was observed on unburied limbs in autumn or winter, most likely due to low ambient temperatures and precipitation. In spring, limited colonisation by flies of the families Calliphoridae and Sarcophagidae occurred on unburied limbs after the 5th day, with minimal larval development. In summer, rapid and extensive insect colonisation of unburied limbs was observed from the 2nd day, peaking on the 5th day and resulting in near-complete soft tissue loss by the 8th day. Buried limbs showed no insect presence throughout the study, with only occasional beetles of the genus Creophilus and Saprinus detected in summer. These findings demonstrate that season and burial strongly influence insect activity and decomposition rates in Slovenia. The results provide the first locally derived detailed forensic entomology reference data applicable to veterinary forensic practice and support more accurate PMI estimation in criminal investigations involving animal abuse, based on the entomological findings at the crime scene.
Razgradnja zakopanih in nezakopanih prašičjih ostankov pod vplivom insektov za določanje postmortalnega intervala v različnih letnih časih v razmerah zmernega celinskega podnebja Slovenije
Izvleček: Forenzična entomologija postaja vse pomembnejše orodje za določanje posmrtnega intervala (PMI) v veterinarskih forenzičnih preiskavah, zlasti v primerih suma mučenja živali, ki je v Republiki Sloveniji opredeljeno kot kaznivo dejanje po 341. členu Kazenskega zakonika. Zanesljiva ocena posmrtnega intervala je v takšnih primerih ključnega pomena. Za čim bolj natančno določanje PMI morajo biti podatki o vplivu žuželk na razpad trupla lokalno specifični, vendar do sedaj v Sloveniji nismo imeli na voljo regijsko pridobljenih forenzično-entomoloških podatkov. Namen raziskave je bil preučiti vpliv letnega časa in zakopa na kolonizacijo žuželk, razvoj njihovih ličink ter razgradnjo tkiv v naravnih razmerah zmernega podnebja v Sloveniji. V raziskavo smo vključili zadnje okončine 40 domačih prašičev (Sus scrofa domestica), pri čemer smo polovico okončin pustili na površini tal, drugo polovico pa zakopali v zemljo na globino 50 cm. Kolonizacijo žuželk in razkroj okončin smo spremljali v štirih letnih časih, od jeseni 2022 do poletja 2023. Na nezakopanih okončinah jeseni in pozimi nismo zaznali aktivnosti žuželk, kar je najverjetneje posledica nizkih temperatur in povečane količine padavin. Spomladi smo opazili manjše število muh in ličink iz družin Calliphoridae in Sarcophagidae, pri čemer je bil razvoj ličink minimalen. Poleti je bila kolonizacija žuželk na nezakopanih okončinah hitra in obsežna; ličinke so bile prisotne že drugi dan po izpostavitvi, vrh njihove aktivnosti pa smo zaznali peti dan. Do konca osmega dne je prišlo do skoraj popolne izgube mehkih tkiv. Na zakopanih okončinah aktivnosti žuželk nismo opazili, z izjemo poletnega obdobja, ko so se pojavili posamezni hrošči iz rodu Creophilus in Saprinus, ki pa niso imeli bistvenega vpliva na razgradnjo tkiv. Rezultati raziskave poudarjajo pomen lokalnega preučevanja vpliva letnega časa in zakopa na aktivnost žuželk ter posledično na hitrost razgradnje trupla. Izsledki predstavljajo prve lokalne referenčne podatke za forenzično-entomološko presojo PMI v veterinarski forenzični medicini v Sloveniji.
Ključne besede: posmrtno; entomologija; žuželke; Slovenija; forenzična
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