Rates of development of immatures of three species of Chrysomya (Diptera: Calliphoridae) reared in different types of animal tissues: implications for estimating the postmortem interval

Developmental differences in spatially distinct populations of the forensically relevant blow fly Lucilia sericata - About the comparability of developmental studies (and case work application)

The cosmopolitan blow fly Lucilia sericata is often used in forensic case work for estimating the minimum postmortem interval (PMImin). For this, the age of immature specimens developing on the dead body is calculated by measuring the time taken to reach the sampled developmental stage at a given temperature. To test whether regional developmental data of L. sericata is valid on a global scale, the time taken to reach different developmental stages was compared between a population from Mexico and one from Germany at two different constant temperatures. The German population of L. sericata was collected in Frankfurt/Main, while the Mexican population originated near Oaxaca de Juarez and was transported to Germany in the larval stage. Only the F1 generation was used to avoid adaption of the Mexican flies. Eggs were immediately placed at 20 °C and 30 °C. Five times 30 freshly eclosed larvae per replicate (n = 5) were then transferred to a cup of minced meat in separate containers. The larvae were checked every 8 h for migration, pupariation or emergence of adult flies. The time at which the first individual and 50 % of the specimens per container entered each of these stages, was recorded. Significant differences in the time of development between the two populations were observed at both temperatures. At 20 °C, the first specimens of the Mexican population reached all developmental stages a little (< 1 day to < 2 days) earlier than the German L. sericata. At 30 °C, the Mexican flies also reached the post-feeding stage slightly earlier (0.2 days). However, at 30 °C, the German flies started pupariation significantly earlier (after 5 days) than the Mexican flies (6.9 days) and the adults from Germany also emerged earlier (10.5 days compared to 13.1 days). The same pattern was observed when looking at 50 % of the total number of specimens per container. A comparison with previously published developmental studies was difficult as the experimental design varied widely between studies. However, the results were within the range of most studies. Our study has shown that age estimation can vary widely depending on the population on which the reference data used for the calculations are based. This highlights the importance of using local and population-specific developmental data for estimating the age of blow flies in case work.

The Impact of Diet and Photoperiodism on the Life History of Thanatophilus sinuatus (Coleoptera: Silphidae)

The forensically important genus Thanatophilus Leach, 1815 (Coleoptera: Silphidae) is a widespread group of carrion beetles that occupies the Holarctic and Afrotropical realms. It has recently received more recognition, as its species are frequently detected on large carrion, including humans, and can be useful in estimating the time of colonization (TOC) and the post-mortem interval (PMI). The immature stages of Thanatophilus sinuatus (Fabricius, 1775) were reared on three different meat diets (pork liver, pork muscle, and chicken muscle). Diet influence on some of the essential life history traits of the species was examined for different populations. Our findings indicated an accelerated development on pork muscle followed closely by pork liver and a prolonged development on chicken muscle. The diet significantly affected the size, and the body condition (weight/ size) as both pork muscle and liver produced individuals in better physical condition (larger and heavier). The impact of two cyclic photoperiod regimes (16 h Light (L): 8 h Dark (D) and 12 h L: 12 h D) was further evaluated and indicated no significant variability.

Review on forensic importance of myiasis: Focus on medicolegal issues on post-mortem interval estimation and neglect evaluation

Myiasis is the infestation of live vertebrates by dipterous larvae that feed on living or necrotic tissues, liquid body substances or ingested food and develop in or on the vertebrate body. In both animals and humans, myiasis plays a fundamental role in forensic practice because of its implications in the evaluation of cases of neglect and in the mPMI (minimum post-mortem interval) estimation. The present study aims to provide a review of forensic issues related to myiasis. A retrospective analysis was conducted by exploring major electronic literature databases. Methodological evaluation of each study was performed according to the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) standards. Sixty-one papers were included in this review. Entomology shows great potentiality in forensic investigations, mostly because of its contributory role in mPMI estimation. Such evaluation, however, requires a careful consideration of the possibility of an ante-mortem myiasis infestation, which could complicate the correct assessment of the mPMI. Hence, forensic pathologists should pay attention to the entomological fauna on a corpse, in both fresh and decomposed bodies. Moreover, in cases with poor nutritional or hygienic conditions, myiasis should be carefully evaluated as an indicator of neglect.

Diet Impact on the Development and Survival of Oiceoptoma thoracicum (Coleoptera: Silphidae)

We assessed the influence of diet on the development and survival in the immature stages of the necrophagous beetle Oiceoptoma thoracicum (Linnaeus, 1758). The species is frequently observed on large cadavers, including humans, and thus can be of potential forensic relevance. We compared multiple meat tissues from three animal sources, and detected the optimal diet for rearing the species for further entomological and forensic objectives. We reared 203 individuals to adulthood at the constant temperature of 20°C. Our results represent the first robust data set of the development time for this species. They further confirmed a significant relationship between survival and the type of diet, as the highest survival rates were detected in larvae fed with both pork liver and pork muscle.

Effects of Tissue Type and Temperature on Selected Life-History Traits of the Flesh Fly, Sarcophaga crassipalpis (Macquart, 1839) (Diptera: Sarcophagidae)

The flesh fly, Sarcophaga crassipalpis Macquart 1839 (Diptera: Sarcophagidae), colonizes estimation of the minimum post-mortem interval (min-PMI). This study examined the effects of different types of tissues and temperature on the development of S. crassipalpis. To the best of our knowledge, the present study is the first to investigate the effects of life-history information of S. crassipalpis. Larvae were reared on three tissue types, chicken heart, bovine minced meat, and bovine tongue, at five temperatures, 15, 20, 25, 30, and 32°C. Pupal and larval development time, adult weight, and pupal and larval survival differed significantly for tissue type and temperature. Temperature had a significant effect on pupal weight but tissue type did not significantly affect pupal weight. The duration of the larval and pupal stages (except of chicken heart, 30°C) decreased with increasing temperature, except for 32°C, in all tissue types. Larval survival was lowest at 32°C in bovine minced meat, bovine tongue, and chicken heart, and at 32°C, all pupae failed to reach the adult stage in minced meat. The results of this study highlight the necessity of considering larval diet and temperature in forensic investigations.

Characterized Gene Repertoires and Functional Gene Reference for Forensic Entomology: Genomic and Developmental Transcriptomic Analysis of Aldrichina grahami (Diptera: Calliphoridae)

Many flies of Diptera are common entomological evidence employed in forensic investigation. Exploring the existence of inter- and intra-species genomic differences of forensically relevant insects is of great importance. Aldrichina grahami is a common blow fly species of forensic importance. The present study characterized the gene repertoires of A. grahami, and provides insights into issues related to forensic entomology, such as necrophagous behavior, gene family features, and developmental patterns. Gene families were clustered and classified according to their function in different aspects of the necrophagous lifestyle, generating several gene repertoires. The genes under positive selection pressure and evolutionary changes were screen and identified. Moreover, genes that exhibited potential prediction value in the post mortem interval (PMI) estimation and development of immature stages were subjected to analysis based on the developmental transcriptome. Related insect species were compared at the genomic level to reveal the genes associated with necrophagous behaviors. The expression of selected genes in separated repositories was verified using qPCR. This work was conducted using a high-quality chromosome-level genome assembly of A. grahami and its developmental transcriptome. The findings will facilitate future research on A. grahami and the other forensically important species.

Intrapuparial Development and Age Estimation of Calliphora grahami (Diptera: Calliphoridae) for Postmortem Interval Estimation

Calliphora grahami (Aldrich, 1930) (Diptera: calliphoridae) is a forensically important blow fly that is widely distributed across Asia, North America, Russia, and Mexico. Calliphora grahami is frequently found on corpses during the spring, autumn, and winter seasons. It is among the early colonizers of cadavers during the cold season, and sometimes, the only necrophagous blow fly on cadavers. Therefore, this species is of forensic significance, although very few studies have explored the application of its intrapuparial age for PMI estimation. This study aimed to examine the intrapuparial development of C. grahami and establish a method for estimating its intrapuparial age. Herein, the C. grahami puparia were studied under six different temperatures (13, 16, 19, 22, 25, and 28°C) for the intrapuparial age estimation, and a total of 5776 puparia were sampled. The morphological changes were divided into 11 stages based on the 1) development of legs and wings, 2) differentiation of the head, thorax, and abdomen, 3) growth and color of the bristles, and 4) color changes of the compound eyes. The corresponding time of each stage was determined. Moreover, the observation and classification of individual morphological features, including compound eyes, antennae, mouthparts, thorax, abdomen, legs, and wings was used to improve the precision of intrapuparial age estimation. The findings of this study provide important information on the use of C. grahami intrapuparia to estimate the minimum postmortem interval (PMImin).

Influence of Diet on Development and Survival of Thanatophilus rugosus (Coleoptera: Silphidae)

This study examined the effects of various diets on the development time and survival of the carrion beetle Thanatophilus rugosus (Fabricius, 1775). We attempted to find the best diet for rearing the species in laboratory conditions for entomological research and forensic purposes, and to further understand its feeding habits. The larval stages were monitored while feeding on three types of meat under a constant temperature. We discovered that the shortest development time in total was achieved in larvae fed with pork liver, followed closely by pork muscle. The longest development and lowest survival rates were observed when introducing a chicken diet. We were also able to identify specific stages during which the diet significantly affected the development.

Development of Chrysomya albiceps (Wiedemann, 1819) (Diptera: Calliphoridae) from the Jazan region of Southwest Saudi Arabia under different laboratory temperatures: applications in forensic entomology

Background

Chrysomya albiceps (Wiedemann, 1819) (blowflies), family Calliphoridae, is important in forensic entomology, where the minimum and maximum postmortem intervals (PMI) are estimated on the basis of the developmental stages of Diptera larvae that consume dead tissue. The present study was designed to estimate the effects of different ambient temperatures (20, 25, and 30 °C) under controlled laboratory conditions on the developmental stages of C. albiceps from the Jazan region, Saudi Arabia.

Results

The present study showed that the larval body weight and length were significantly increased when larvae were reared at 30 °C compared with corresponding values at 24 h, 48 h, and 72 h at rearing temperatures of 20 °C and 25 °C; however, the weight and length were significantly decreased compared with corresponding values at 96 h at 20 °C and 25 °C. The pupation time was inversely related to the rearing temperature, occurring at 144, 124, and 120 h at rearing temperatures of 20 °C, 25 °C, and 30 °C, respectively. The pupal weight and length were significantly increased in larvae reared at 30 °C compared with those reared at 20 °C and 25 °C. At 20 °C, 25 °C, and 30 °C, larval durations of 5.00, 5.00, and 4.00 days were recorded, respectively. Pupae and adults showed gradual decreases in life stage durations, at 6.00, 5.30, and 4.80 days in pupae and 20.00, 18.70, and 16.90 days in adults, with increasing rearing temperatures. Average adult longevity at 30 °C (194.40 h) was significantly less than adult longevity at 20 °C (216.00 h) and 25 °C (204.60 h). The results showed an inverse relation between durations of developmental stages and rearing temperatures.

Conclusions

Insect laboratory colonization for the determination of biological characteristics of insects is economically viable for forensic entomology and as a technique for evaluating insect evidence.

Research Progress on Developmental Biology of Sarcosaprophagous Insects

Forensic entomology provides a feasible way to estimate postmortem interval (PMI), of which the growth and development of sarcosaprophagous insects is the most widely used indicator in forensic practice. Over the years, forensic entomologists have carried out a large number of studies on the development biology of sarcosaprophagous insects. This paper illustrates the main factors that affect the development of sarcosaprophagous insects, including temperature, humidity, light, food types and poisons. The development indicators of sarcosaprophagous insects were reviewed from the perspectives of morphology, differential gene expression and biochemical characteristics. It is emphasized that future research of development biology on sarcosaprophagous insects should fully absorb and integrate the methods of artificial intelligence and omics, and the research object also needs further expansion in order to establish a more objective and more accurate PMI estimation method.

Effect of Type of Tissue on the Development of Chrysomya rufifacies (Diptera: Calliphoridae) in Sri Lanka

Chrysomya rufifacies (Macquart), the hairy maggot blow fly, is of great importance for the field of forensic entomology due to its habit as an early colonizer of decomposing vertebrate remains and myiasis producer. Development studies on this species have been conducted in scattered regions of the world, using types of tissue from several species of animals as a rearing medium. Despite the commonality of C. rufifacies in Sri Lanka, developmental studies have never been performed in this region. As well, the effects of diet on development have not been tested. In the current study, C. rufifacies immatures were reared on skeletal muscle, liver, and heart from domestic swine, with flies from colonies maintained at 25 and 28°C. The minimum time needed to complete each stage at 25°C on liver (224.14 h) was fastest followed by skeletal muscle (249.33 h) and heart (251.64 h) respectively, whereas at 28°C, fly development was quickest on heart muscle (178.27 h) followed by liver (178.50 h) and skeletal muscle (186.17 h) respectively. A significant difference in total development time was determined for temperature, while the rearing medium was not significant. Temperature also showed a significant effect on the length and the width of the larvae, while the type of tissue statistically impacted only the width.

Body Size and Cuticular Hydrocarbons as Larval Age Indicators in the Forensic Blow Fly, Chrysomya albiceps (Diptera: Calliphoridae)

Chrysomya albiceps (Wiedemann 1819) is one of the most important insects in forensic entomology. Its larval developmental and survival rates are influenced by nutritional resources, temperature, humidity, and geographical regions. The present study investigated the possibility of relying on body size and cuticular hydrocarbon composition as indicators for age estimation of the different larval instars of C. albiceps. Larvae were maintained in standardized laboratory conditions at different experimental temperatures. All larval instars (first, second, and third) were randomly collected for measuring their body sizes and for estimating their cuticular hydrocarbons at different rearing temperatures (30, 35, 40, and 45°C) using gas chromatography-mass spectrometry (GC-MS). Results indicated that the duration of larval stage was temperature dependent as it gradually decreased on increasing the rearing temperature (30, 35, and 40°C) except 45°C at which larval development was ceased. In contrary, larval body size, in terms of length, width, and weight, was temperature dependent as it gradually increased with larval development on increasing rearing temperature except at 45°C at which larval development was ceased. The GC-MS showed a significant difference in the extracted components of cuticular hydrocarbons between different larval instars reared in the same temperature and between the same larval instar that reared at different temperatures. Furthermore, the highest and lowest amounts of cuticular hydrocarbons were detected at 35 and 40°C, respectively. Overall, larval body size and cuticular hydrocarbon components were temperature dependent within the range 30-40°C, which may suggest them as possible reliable age indicators for estimating the postmortem interval in the field of medicolegal entomology.

Postmortem expression of apoptosis-related genes in the liver of mice and their use for estimation of the time of death

PURPOSE

A major challenge in forensic medicine is to estimate the postmortem interval (PMI). Several approaches had been tried to determine the time of death, including physical and chemical changes. This study aims to explore the postmortem changes in the expression of apoptosis-related genes in the liver of mice and to use these changes for estimation of the PMI.

METHODS

Hepatic tissue was collected from sacrificed mice immediately after death (the control group) and at 3, 6, 9, 12, 18, and 24 hours after death. Four apoptosisrelated genes were selected as target genes, which are Caspase 3 (Casp3), B cell leukemia/ lymphoma 2 (Bcl2), BCL2-associated X protein (Bax), and Transformation related protein 53 (Trp53), and their relative expression was measured using quantitative PCR. miR-122 was used as a reference gene for normalization of the Ct (threshold cycle) values of the target genes.

RESULTS

The results revealed that the postmortem expression of Casp3 increased in a time-dependent manner; the expression of Bax increased from 3 to 18 hours followed by a decrease at 24 hours after death; the expression of Bcl2 decreased in a time-dependent manner after death; the expression of Trp53 increased from 3 to 6 hours and then started to decrease from 9 to 24 hours after death.

CONCLUSION

Based on the observed changes in the expression level of these genes, mathematical models were established to estimate the PMI. Further research is needed to investigate these markers and mathematical models in human tissues.

Intrapuparial Development of Hemilucilia semidiaphana (Diptera: Calliphoridae) and Its Use in Forensic Entomology

In forensic entomology, the minimum postmortem interval (PMImin) estimative is usually based on the oldest immature recovered from a local of death. The time spent by fly immatures in the intrapuparial period comprises more than 50% of their complete life cycles. An accurate estimate of the duration of this period will improve PMImin estimates. The blow fly Hemilucilia semidiaphana (Rondani 1850) was found in six criminal cases in the city of Curitiba. Even though there is data on the morphology of the larval instars and developmental rate of H. semidiaphana, the intrapuparial period has not been investigated. Here, we provide a detailed description of the intrapuparial morphological changes of H. semidiaphana, which might be useful to estimate minimum PMI. Samples of H. semidiaphana in the intrapuparial period were obtained from immatures reared on an artificial diet in incubators adjusted to 25°C or 20°C temperature regimes. Blow fly puparia of H. semidiaphana were fixed at intervals of 3 and 6 h until emergence of the adult. The external morphological traits of sampled immatures were analyzed using light microscopy. Our analysis of the intrapuparial period of H. semidiaphana provided 21 traits from which nine were age informative. These nine characteristics divide the developmental time (144 h at 25°C and 192 h at 20°C) into smaller sections. The developmental data provided, together with the time line allows a practical way to make interspecific comparisons as well as to estimate the age of H. semidiaphana based on the intrapuparial development.

Spatial and Temporal Variation of the Blowflies Community (Diptera: Calliphoridae) From an Urban Area in Northern South America

Blowflies (Diptera: Calliphoridae) are necrophagous flies with ecological, medical, veterinary, and forensic importance. These flies carry pathogens that they spread to animals and humans, and produce myiasis. Furthermore, they are useful tools in forensic science as indicators of postmortem intervals, and in biomedicine they are successfully used in larval therapy. This study aimed to assess the spatiotemporal variation of the blowflies community from the urban area of Sincelejo City, located in the Colombian Caribbean region. Samplings were conducted from May 2012 to April 2013, using Van Someren Rydon-traps baited with bovine meat, fish, and chicken that decomposed for 48 h. Six species were registered, Cochliomyia macellaria (Fabricius, 1775) was the most abundant, followed by Lucilia eximia (Wiedemann, 1819) and Chrysomya albiceps (Wiedemann, 1819), while Chloroprocta idioidea (Robineau-Desvoidy, 1830), Chrysomya megacephala (Fabricius, 1794), and Lucilia cuprina (Wiedemann, 1830) presented the least individuals. The blowflies community did not change significantly throughout the sampling months or between the periods of low or high rainfall, nor was it influenced by weather variables. Although the species composition was the same in all sampled localities, species abundances presented significant differences. The possible causes of this pattern are discussed herein. Sex ratios were female biased for all the recorded species, except C. idioidea. Our findings provide the first assessment of the blowflies community from the urban area of Sincelejo City.

Hyperspectral measurements of immature Lucilia sericata (Meigen) (Diptera: Calliphoridae) raised on different food substrates

Immature Lucilia sericata (Meigen) raised on beef liver, beef heart, pork liver and pork heart at a mean temperature of 20.6°C took a minimum of 20 days to complete development. Minimum development time differences within stages were observed between the meat types (pork/beef), but not the organ types (liver/heart). Daily hyperspectral measurements were conducted and a functional regression was completed to examine the main effects of meat and organ type on daily spectral measurements. The model examined post feeding larval spectral measurements of insects raised on beef liver alone, the effect of those raised on pork compared with those raised on beef, the effect of those raised on heart compared with those raised on liver and the interactional effect of those raised on pork heart compared with those raised on beef liver. The analyses indicated that the spectral measurements of post feeding L. sericata raised on pork and beef organs (liver and heart) are affected by the meat and organ type.

Development of the Oriental Latrine Fly, Chrysomya megacephala (Diptera: Calliphoridae), at Five Constant Temperatures

Chrysomya megacephala (Fabricius) is a forensically important fly that is found throughout the tropics and subtropics. We calculated the accumulated development time and transition points for each life stage from eclosion to adult emergence at five constant temperatures: 15, 20, 25, 30, and 35 °C. For each transition, the 10th, 50th, and 90th percentiles were calculated with a logistic linear model. The mean transition times and % survivorship were determined directly from the raw laboratory data. Development times of C. megacephala were compared with that of two other closely related species, Chrysomya rufifacies (Macquart) and Phormia regina (Meigen). Ambient and larval mass temperatures were collected from field studies conducted from 2001-2004. Field study data indicated that adult fly activity was reduced at lower ambient temperatures, but once a larval mass was established, heat generation occurred. These development times and durations can be used for estimation of a postmortem interval (PMI).

Evaluating the Biological Cycle and Reproductive and Population Parameters of Calliphora vicina (Diptera: Calliphoridae) Reared on Three Different Diets

This work was aimed at evaluating Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae) life cycle, life tables, and reproductive and population parameters. This species is a necrophagous, synanthropic, cosmopolitan fly with broad distribution in the Neotropical region. Six successive generations from adult specimens collected in Bogotá, Colombia, were analyzed in laboratory conditions. The fly's life cycle was evaluated, using a natural diet of pig's liver (L) and two artificial diets-milk powder and egg (ME) and powdered liver (PL). The species' longest life cycle duration (in days), from egg to pupa, was obtained with the ME diet (24.6 ± 6.7) whereas the lowest value was recorded with the L diet (18.8  ±  3.6). Female adult forms achieved high longevity values, this being highest in ME (102.8  ±  3.6). The most efficient diets (L and ME) led to the following average reproductive and population values: 226.2 and 465.4 net reproductive rate (Ro), 22.2 and 47.1 cohort generation time (Tc), 0.24 and 0.13 intrinsic population growth rate (r_m), and 1.27 and 1.13 finite rate of increase (λ). The set of results (in terms of relatively high average values concerning the biological characteristics analyzed) showed the species' adaptability to the environmental and nutritional conditions established in a laboratory setting, thereby enabling their colonization.

Developmental Times of Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae) at Constant Temperatures and Applications in Forensic Entomology

The characteristic life stages of infesting blowflies (Calliphoridae) such as Chrysomya megacephala (Fabricius) are powerful evidence for estimating the death time of a corpse, but an established reference of developmental times for local blowfly species is required. We determined the developmental rates of C. megacephala from southwest China at seven constant temperatures (16-34°C). Isomegalen and isomorphen diagrams were constructed based on the larval length and time for each developmental event (first ecdysis, second ecdysis, wandering, pupariation, and eclosion), at each temperature. A thermal summation model was constructed by estimating the developmental threshold temperature D0 and the thermal summation constant K. The thermal summation model indicated that, for complete development from egg hatching to eclosion, D0 = 9.07 ± 0.54°C and K = 3991.07 ± 187.26 h °C. This reference can increase the accuracy of estimations of postmortem intervals in China by predicting the growth of C. megacephala.

Exploration of the R code-based mathematical model for PMI estimation using profiling of RNA degradation in rat brain tissue at different temperatures

Precise estimation of postmortem interval (PMI) is crucial in some criminal cases. This study aims to find some optimal markers for PMI estimation and build a mathematical model that could be used in various temperature conditions. Different mRNA and microRNA markers in rat brain samples were detected using real-time fluorescent quantitative PCR at 12 time points within 144 h postmortem and at temperatures of 4, 15, 25, and 35 °C. Samples from 36 other rats were used to verify the animal mathematical model. Brain-specific mir-9 and mir-125b are effective endogenous control markers that are not affected by PMI up to 144 h postmortem under these temperatures, whereas the commonly used U6 is not a suitable endogenous control in this study. Among all the candidate markers, ΔCt (β-actin) has the best correlation coefficient with PMI and was used to build a new model using R software which can simultaneously manage both PMI and temperature parameters. This animal mathematical model is verified using samples from 36 other rats and shows increased accuracy for higher temperatures and longer PMI. In this study, β-actin was found to be an optimal marker to estimate PMI and some other markers were found to be suitable to act as endogenous controls. Additionally, we have used R code software to build a model of PMI estimation that could be used in various temperature conditions.

Helminthes and insects: maladies or therapies

By definition, parasites cause harm to their hosts. But, considerable evidence from ancient traditional medicine has supported the theory of using parasites and their products in treating many diseases. Maggots have been used successfully to treat chronic, long-standing, infected wounds which failed to respond to conventional treatment by many beneficial effects on the wound including debridement, disinfection, and healing enhancement. Maggots are also applied in forensic medicine to estimate time between the death and discovery of a corpse and in entomotoxicology involving the potential use of insects as alternative samples for detecting drugs and toxins in death investigations. Leeches are segmented invertebrates, famous by their blood-feeding habits and used in phlebotomy to treat various ailments since ancient times. Leech therapy is experiencing resurgence nowadays in health care principally in plastic and reconstructive surgery. Earthworms provide a source of medicinally useful products with potential antimicrobial, antiviral, and anticancer properties. Lumbrokinases are a group of fibrinolytic enzymes isolated and purified from earthworms capable of degrading plasminogen-rich and plasminogen-free fibrin and so can be used to treat various conditions associated with thrombotic diseases. Helminth infection has been proved to have therapeutic effects in both animal and human clinical trials with promising evidence in treating many allergic diseases and can block the induction of or reduce the severity of some autoimmune disorders as Crohn's disease or ulcerative colitis. What is more, venomous arthropods such as scorpions, bees, wasps, spiders, ants, centipedes, snail, beetles, and caterpillars. The venoms and toxins from these arthropods provide a promising source of natural bioactive compounds which can be employed in the development of new drugs to treat diseases as cancer. The possibility of using these active molecules in biotechnological processes can make these venoms and toxins a valuable and promising source of natural bioactive compounds. The therapeutic use of helminthes and insects will be of great value in biomedicine and further studies on insect toxins will contribute extensively to the development of Biomedical Sciences.