Diptera (Dryomyzidae, Fanniidae, Muscidae, Piophilidae) Associated With Pig Carcasses in a Forest Habitat of Poland: Sex-Related Patterns of Visitation and Effectiveness of Sampling Methods

Our knowledge on many necrophilous dipterans was limited for a long time mainly due to taxonomic issues. Therefore, findings on the sex-related associations with pig carcasses in Dryomyzidae, Fanniidae, Muscidae, and Piophilidae are presented. Moreover, the effectiveness of pitfall traps and sweep nets in fly sampling were compared, since the correct method of collecting insects is critical for the development and application of entomological tools for forensic purposes. The trapped numbers of all species differed significantly in respect to both sexes. The sex ratios were strongly female-biased in most species of Muscidae and in Fanniidae. More females were also collected in Piophilidae, but the proportion of males was higher when compared to muscids. Within Dryomyzidae, the sex ratio differed according to species. Only Dryomyza flaveola (Fabricius, 1794) (Diptera: Dryomyzidae) and Muscina pascuorum (Meigen, 1826) (Diptera: Muscidae) had male-biased sex ratios. Differences in residency patterns between sexes in Stearibia nigriceps (Meigen, 1826) (Diptera: Piophilidae), Liopiophila varipes (Meigen, 1830) (Diptera: Piophilidae), and D. flaveola were statistically insignificant. All studied species were recorded for each sampling method. The effect of the sampling method on the number of individuals was statistically significant for all dipterans but Piophilidae. Pitfall traps outcompeted the aerial sweep net in representing Dryomyzidae and Muscidae, whereas both methods were almost equally effective in the collection of Piophilidae. A varied effectiveness of sampling methods was observed in Fanniidae. The sampling method significantly affected the determination of the appearance time of flies on carcasses, but the effect of species and sampling method was insignificant. Implications for forensic entomology are discussed.

Competition of insect decomposers over large vertebrate carrion: Necrodes beetles (Silphidae) vs blow flies (Calliphoridae)

Large carrion is inhabited by highly variable and interactive communities of insects. Positive interactions in carrion insect communities have been recently the focus in carrion ecology. By contrast, competition between carrion insects is rather undervalued. Here we provide evidence that blow flies (Calliphoridae) and Necrodes beetles (Silphidae), dominant decomposers of large carcasses in terrestrial habitats, compete over carrion. By reanalysing the results from 90 pig carcasses we demonstrated that the contribution of the flies and the beetles to the decay was negatively related. The greater part of the large carrion pool was monopolised by blow flies, whereas Necrodes beetles abundantly colonized carcasses, on which blow flies were less effective as decomposers. In behavioural assays, we found that adult beetles killed four times more frequently feeding than postfeeding third instar larvae of the flies, with the large decrease in the killing frequency after the larvae reached the age of early third instar. Therefore, adult Necrodes beetles preferentially killed the larvae that were before or in their peak feeding. The study provides evidence that the interaction between blow flies and Necrodes beetles is a combination of indirect exploitative effects of the flies and direct interference effects of the beetles (the mixed competition).

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

The current study aimed at molecular identification and comparing the diversity of arthropods communities between pig and sheep carcasses during the cold and warm season in KwaZulu-Natal province of South Africa. Adult arthropods found on and around the carcasses were collected using either fly traps or forceps. Molecular analyses confirmed the identification of twelve arthropod species collected from both sheep and pig carcasses during the cold season. Results showed that 11 of 12 arthropod species were common in both sheep and pig carcasses, with exception to Onthophagus vacca (Coleoptera: Scarabaeidae) (Linnaeus, 1767) and Atherigona soccata (Diptera: Muscidae) (Rondani, 1871) species which were unique to sheep and pig carcasses respectively. However, during the warm season, the sheep carcass attracted more arthropod (n = 13) species as compared to the pig carcass. The difference in the obtained arthropod was due to the presence of O. vacca which was also unique to the sheep carcass during this season. Furthermore, there was an addition of a beetle species Hycleus lunatus (Coleoptera: Meloidae) (Pallas, 1782), which was collected from both sheep and pig carcasses but unique to the warm season. The pig carcass attracted more dipteran flies during both warm (n = 1,519) and cold season (n = 779) as compared to sheep carcass during the warm (n = 511) and cold season (n = 229). In contrast, coleopterans were more abundant on the sheep carcass during the warm season (n = 391) and cold season (n = 135) as compared to the pig carcass in both warm season (n = 261) and cold season (n = 114). In overall, more flies and beetles were collected on both sheep and pig carcasses during the warm season, and this further highlight that temperature influenced the observed difference in the abundance of collected arthropod between seasons.

Diagnostic accuracies of CTs, X-rays and Lodox to detect blunt force trauma in adults, using a pig model

The accurate radiological detection of skeletal trauma is crucial for the investigation of blunt force trauma (BFT) cases. The sensitivities of CTs, X-rays and Lodox in identifying BFT fractures and minimum number of impacts in pigs, used as proxies for adult humans, were assessed. Ten human sized pig carcasses were struck with a mallet and scanned, after which the number of fractures and minimum number of impacts detected radiologically were recorded. Pig carcasses were then macerated, and the defleshed, skeletonized remains were considered the gold standard as far as number and location of fractures were concerned. CTs were most sensitive in identifying fractures and impacts in all body regions, with overall sensitivities of 55.4% and 71.5% respectively, while X-rays and Lodox had sensitivities of 25.8% and 29.3% for fractures, and 43.5% and 41.1% for impacts, respectively. All modalities were highly specific for identifying fractures (CT: 99.1%; X-ray: 98.9%; Lodox: 99.4%). CTs should be used to analyze blunt force trauma when a radiological assessment is required, but an examination of the defleshed bones remains the gold standard for the deceased whenever feasible. X-rays and Lodox have limited diagnostic value in these cases and relying on them to detect fractures may compromise the accurate forensic investigation of blunt trauma victims. However, the use of Lodox for initial screening of major trauma is still of value. Sensitivities are generally higher for detecting fractures in pigs compared to piglets, indicating that increased diagnostic value is achieved when imaging pigs compared to piglets.

Economic efficiency of veterinary measures in the conditions of all-russian reforms in 2010-2020

The list of OIE identifies especially dangerous and other contagious diseases (83 — diseases of terrestrial animals, 48 — diseases of aquatic animals), including those common to humans and animals (zoonoses), including food more than 200. Veterinary science is tasked with ensuring the well-being of individual animal diseases: socially significant (brucellosis, tuberculosis, leptospirosis, etc.), as well as economically significant (African swine fever, bird flu, foot-and-mouth disease, etc.). It should be borne in mind that 80 % of pathogens that can be used for biological terrorism are also pathogens of zoonotic infections. In addition, the sources of causative agents of basic human food toxico-infections (salmonella, escherichia, yersenia, listeria, campylobacteria) are [4]. Foodstuffs occupy a special place among material goods, because they meet the vital need of people [6]. In the EU countries, zoonosis and food toxico infections are monitored. Monitoring results showed that the first and second most commonly reported zoonoses in humans were campylobacteriosis and salmonellosis. The EU trend for confirmed cases of people with these two diseases was stable (unchanged) during 2015–2019 years. The prevalence in the EU of salmonellous herd serovarpolozhitelnykh targeting salmonella has been stable since 2015 for breeding chickens, laying chickens, broilers and fattening turkeys, with fluctuations for breeding herds of turkeys. The results for salmonella obtained by the competent authorities for pig carcasses and poultry tested under national control programmes were more likely to be positive than those obtained from food industry operators. Escherichia coli infection (STEC), Siga toxin-producing, was the third most reported zoonosis in humans and increased from 2015 to 2019. Yersiniosis was the fourth most reported zoonosis in humans in 2019 with a stable trend in 2015–2019. Listeria rarely exceeded the EU food safety limit tested in ready-to-eat foods. A total of 5,175 food-borne outbreaks were reported. Salmonella remained the most identified causative agent, but the number of outbreaks caused by S. Enteritidis decreased. Norovirus contained in fish and fish products was a pair of agent/food that caused the largest number of outbreaks with convincing evidence. The report provides further updated information on bovine tuberculosis, Brucella, trichinella, echinococcus, Toxoplasma, rabies, West Nile virus, coccyella burnetia (Q-fever) and tularemia [3, 5, 7]. During diagnostic studies of imported cattle imported from Golandia, Germany, Switzerland, 7 subjects revealed positively responding animals to bluetang. The most serious situation regarding epizootic well-being, biological and economic security has developed in the African swine fever [4].

Research on the Distribution of Coronary Arteries in Pig (Sus Scrofa Domesticus)

Pigs are some of the most widely used experimental models, an advantage being the characteristics of homeostasis and many morphological features comparable to those in humans. For this reason, we addressed this topic in this paper, with the major objective of completing the data and even identifying some features not described in the literature. The present study was performed on 20 pig carcasses, with different weights and ages (2-4 months). The aim was to highlight some peculiarities regarding the coronary artery system in this species, using as a method the injection of vessels with contrasting plastic material. The collaterals and terminals of the coronary arteries, their distribution territories as well as the identified individual variants were described. As a general conclusion, regardless of the polymorphism in all dissected cases, the left coronary artery was the dominant artery, there being no exception from the data known in the literature.

Bacterial Communities Associated with Human Decomposition

<p>Human decomposition is a little-understood process with even less currently known about the microbiology involved. The aim of this research was to investigate the bacterial community associated with exposed decomposing mammalian carcasses on soil and to determine whether changes in this community could potentially be used to determine time since death in forensic investigations. A variety of soil chemistry and molecular biology methods, including molecular profiling tools T-RFLP and DGGE were used to explore how and when bacterial communities change during the course of a decomposition event. General bacterial populations and more specific bacterial groups were examined. Decomposition was shown to cause significant and sequential changes in the bacterial communities within the soil, and changes in the bacterial community often correlated with visual changes in the stage of decomposition. Organisms derived from the cadavers and carcasses were able to be detected, using molecular methods, in the underlying soil throughout the decomposition period studied. There was little correlation found between decomposition stage and the presence and diversity within the specific bacterial groups investigated. Organisms contributing to the changes seen in the bacterial communities using molecular profiling methods were identified using a cloning and sequencing based technique and included soil and environment-derived bacteria, as well as carcass or cadaver-derived organisms. This research demonstrated that pig (Sus scrofa) carcass and human cadaver decomposition result in similar bacterial community changes in soil, confirming that pig carcasses are a good model for studying the microbiology of human decomposition. The inability to control for differences between donated human cadavers made understanding the human cadaver results difficult, whereas pig carcass study allowed many variables to be held constant while others were investigated. The information gained from this study about the bacteria associated with a cadaver and how the community alters over the course of decomposition may, in the future, enable the development of a forensic post mortem interval estimation tool based on these changes in the bacterial community over time. The findings in this thesis suggest that high variability between human bodies and their microflora is likely to present a challenge to the development of such a tool, but further study with emerging high-throughput molecular tools may enable identification of microbial biomarkers for this purpose.</p>

Bacterial Communities Associated with Human Decomposition

<p>Human decomposition is a little-understood process with even less currently known about the microbiology involved. The aim of this research was to investigate the bacterial community associated with exposed decomposing mammalian carcasses on soil and to determine whether changes in this community could potentially be used to determine time since death in forensic investigations. A variety of soil chemistry and molecular biology methods, including molecular profiling tools T-RFLP and DGGE were used to explore how and when bacterial communities change during the course of a decomposition event. General bacterial populations and more specific bacterial groups were examined. Decomposition was shown to cause significant and sequential changes in the bacterial communities within the soil, and changes in the bacterial community often correlated with visual changes in the stage of decomposition. Organisms derived from the cadavers and carcasses were able to be detected, using molecular methods, in the underlying soil throughout the decomposition period studied. There was little correlation found between decomposition stage and the presence and diversity within the specific bacterial groups investigated. Organisms contributing to the changes seen in the bacterial communities using molecular profiling methods were identified using a cloning and sequencing based technique and included soil and environment-derived bacteria, as well as carcass or cadaver-derived organisms. This research demonstrated that pig (Sus scrofa) carcass and human cadaver decomposition result in similar bacterial community changes in soil, confirming that pig carcasses are a good model for studying the microbiology of human decomposition. The inability to control for differences between donated human cadavers made understanding the human cadaver results difficult, whereas pig carcass study allowed many variables to be held constant while others were investigated. The information gained from this study about the bacteria associated with a cadaver and how the community alters over the course of decomposition may, in the future, enable the development of a forensic post mortem interval estimation tool based on these changes in the bacterial community over time. The findings in this thesis suggest that high variability between human bodies and their microflora is likely to present a challenge to the development of such a tool, but further study with emerging high-throughput molecular tools may enable identification of microbial biomarkers for this purpose.</p>

Prevalence, Molecular Characterization and Antimicrobial Susceptibility of Clostridioides difficile Isolated from Pig Carcasses and Pork Products in Central Italy

In the last decade, the incidence and severity of Clostridioides difficile infections (CDIs) in humans have been increasing and community-associated infections have been described. For these reasons, the interest in C. difficile in food and in food animals has increased, suggesting other possible sources of C. difficile acquisition. This study evaluated the presence of C. difficile on pig carcasses at the slaughterhouse and in pork products in Central Italy. The contamination rate on pig carcasses was 4/179 (2.3%). Regarding food samples, a total of 216 pork products were tested (74 raw meat preparations and 142 ready-to-eat food samples made by cured raw meat). The real-time PCR screening was positive for 1/74 raw meat preparation (1.35%) and for 1/142 ready-to-eat food samples (0.7%) C. difficile was isolated only from the raw meat preparation (pork sausage). All the isolated strains were toxigenic and susceptible to all the tested antibiotics. Strains isolated from carcass samples displayed A+B+CDTa+CDTb+ profile, were toxinotype IV and belonged to the same ribotype arbitrary named TV93, while the one isolated from food samples displayed A+B+CDTa-CDTb- profile and it was not possible to determine ribotype and toxinotype, because it was lost after freeze storage. It was concluded that the prevalence of C. difficile in the pork supply chain is very low.