Toxic Secretions Research Articles

Comprehensive Analysis of Bufadienolide and Protein Profiles of Gland Secretions from Medicinal Bufo Species.

Toad Venom (TV) is the dried product of toxic secretions from Bufo bufo gargarizans Cantor (BgC) or B. melanostictus Schneider (BmS). Given the increasing medical demand and the severe depletion of wild toads, a number of counterfeit TVs appeared on the market, posing challenges to its quality control. In order to develop an efficient, feasible, and comprehensive approach to evaluate TV quality, a thorough analysis and comparison of chemical compounds among legal species BgC and BmS, as well as the main confusion species B. andrewsi Schmidt (BaS) and B. raddei Strauch (BrS), were conducted by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS), high performance liquid chromatography (HPLC), sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and Nano LC-MS/MS analyses. We identified 126 compounds, including free or conjugated bufadienolides, indole alkaloids and amino acids, among the four Bufo species. The content of main bufadienolides, such as gamabufotalin, bufotalin, bufalin, cinobufagin, and resibufogenin, and the total protein contents varied widely among 28 batches of TV due to their origin species. The sum of the five bufadienolides within the BgC, BmS, BaS, and BrS samples were 8.15-15.93%, 2.45-4.14%, 11.15-13.50%, and 13.21-14.68%, respectively. The total protein content of BgC (6.9-24.4%) and BaS (19.1-20.6%) samples were higher than that of BmS (4.8-20.4%) and BrS (10.1-13.7%) samples. Additionally, a total of 1357 proteins were identified. There were differences between the protein compositions among the samples of the four Bufo species. The results indicated that BgC TV is of the highest quality; BaS and BrS TV could serve as alternative resources, whereas BmS TV performed poorly overall. This research provides evidence for developing approaches to evaluate TV quality and selecting the proper Bufo species as the origin source of TV listed in the Chinese pharmacopoeia.

The effect of biofluorescence on predation upon Cope’s gray treefrog: A clay model experiment

Biofluorescence, the ability to absorb light and reemit it at a longer wavelength, is present in many taxa but has been examined only recently in amphibians. Over half of the studies documenting biofluorescence in the last century suggest this fluorescent signal may affect predation; however, to date, only one other experimental study has tested this hypothesis. To address this question, we experimentally tested the effect of biofluorescence on predation through the study of the Cope’s Gray Treefrog, Hyla chrysoscelis. First, we quantified the spectral characteristics of a novel biofluorescence pattern in H. chrysoscelis. In both sexes of this species, the fluorescent signal is concentrated in an area that contains a proposed aposematic pattern to warn predators of the frog’s toxic secretions. We hypothesized that the biofluorescent trait may increase the conspicuousness of this pattern and enable the frogs to deter predators more effectively. Second, we tested this prediction by conducting a clay model field experiment to assess differences in predation attempts on fluorescent versus non-fluorescent H. chrysoscelis models by various predator types. We found no effect of biofluorescence on the overall presence, type, or location of predation, suggesting that biofluorescence alone does not act as an antipredator signal of H. chrysoscelis. This study represents one of the first attempts to experimentally test the effect of biofluorescence on predation in any organism and the first to do so in amphibians. Further work is needed to explore the role of this trait in predation in other systems and to investigate alternative functions for the biofluorescent signal in H. chrysoscelis.

Molecular Characterization of Ixodid Ticks Infesting Cattle

There is great diversity of ticks with only three genera; Amblyomma, Hyalomma, and Rhipicephalus known to have highest impact on livestock health. Ticks suck blood and release toxic secretions from saliva through their mouth appendage into cattle resulting in anaemia, skin damage, inflammation, paralysis, reduced weight gain, and reduction in milk production. Proper tick identification is imperative to understand tick-borne pathogens as well as determine control measures. Molecular approach has made the identification of tick species easy. This study therefore used molecular tools to determine the identity of ticks collected from cattle in Iwo Osun state, Southwest Nigeria. Cross-sectional study of ticks was done in August 2022. Different species of ticks (n = 268) were collected from cows. The samples were collected in sterile tubes and stored in 70% ethanol before DNA extraction, amplification and sequencing. Ticks were morphologically identified using available keys. Amblyomma, n=170 (63.4%), Hyalomma, n=61 (22.8%) and Rhipicephalus, n=37 (13.8%) were identified. Molecular and phylogenetic analysis of the two morphotypes whose cytochrome c oxidase subunit 1 (COI) gene amplified revealed that they were Amblyomma variegatum and Rhipicephalus microplus. This study characterized Amblyomma variegatum and Rhipicephalus microplus ticks by sequencing the COI gene and it expands the knowledge of tick parasitofauna on cows in Iwo Osun state, Southwest Nigeria.

The use of a pumice stone in removal of petroleum hydrocarbons from industrial wastewater through coagulation and flocculation

Background: Petroleum hydrocarbons that are released from industrial processes cause damage to aquatic life and degrade ecosystems by accumulating in the food chain, allowing living organisms to produce toxic secretions. Methods: In this study, a pumice stone was used to remove total petroleum hydrocarbons (TPHs) from industrial wastewater in the south refinery company in Iraq/Basrah by coagulation and flocculation processes using the design of experiments (DOE) approach using the method of analyzing screening designs and measurement of the samples using GC instrument. Results: The maximum removal was 99% at pH 3, coagulation dose of 0.5 g, and time of 60 min, and a comparison was made between the DOE and the multiple linear regression (MLR) to determine the effectiveness of the system used, which proved its incredible effectiveness. Conclusion: According to the results, a great convergence between the actual and prediction results of removal was found, while MLR was very far from the actual and predicted removal results. The high efficiency of pumice stone was found in removing petroleum hydrocarbons from the industrial wastewater of the South Refineries Company. Pumice stone is widely available in the market and cheap economically.

How to Survive a (Juvenile) Piranha Attack: An Integrative Approach to Evaluating Predator Performance.

Cory cat panel figureDrawing of bite force measuring equipment and indentation rig Pygocentrus nattereri jaw muscle morphology and skull anatomyBox plot grid of number of Pygocentrus nattereri bites before puncture along different body regions of Corydoras trilineatus during feeding trials resultsDrawing of color-coded Corydoras trilineatus with attack frequencies and average bites until puncture by Pygocentrus nattereriBox plot of average voluntary juvenile Pygocentrus nattereri bite forces to standard lengthPanel of linear ordinary least-squares regressions of Pygocentrus nattereri bite force to adductor mandibulae mass, standard length, and body massOrdinary least-squares regressions of voluntary bites to restrained bites of Pygocentrus nattereriPanel of indentation tests for intact and removed Corydoras trilineatus scutesPanel of indentation tests for Corydoras trilineatus body region. There is an evolutionary arms race between predators and prey. In aquatic environments, predatory fishes often use sharp teeth, powerful bites, and/or streamlined bodies to help capture their prey quickly and efficiently. Conversely, prey are often equipped with antipredator adaptations including: scaly armor, sharp spines, and/or toxic secretions. This study focused on the predator-prey interactions between the armored threestripe cory catfish (Corydoras trilineatus) and juvenile red-bellied piranha (Pygocentrus nattereri). Specifically, we investigated how resistant cory catfish armor is to a range of natural and theoretical piranha bite forces and how often this protection translated to survival from predator attacks by Corydoras. We measured the bite force and jaw functional morphology of P. nattereri, the puncture resistance of defensive scutes in C. trilineatus, and the in situ predatory interactions between the two. The adductor mandibulae muscle in juvenile P. nattereri is robust and delivers an average bite force of 1.03 N and maximum bite force of 9.71 N, yet its prey, C. trilineatus, survived 37% of confirmed bites without any damage. The C. trilineatus armor withstood an average of nine bites before puncture by P. nattereri. Predation was successful only when piranhas bit unarmored areas of the body, at the opercular opening and at the caudal peduncle. This study used an integrative approach to understand the outcomes of predator-prey interactions by evaluating the link between morphology and feeding behavior. We found that juvenile P. nattereri rarely used a maximal bite force and displayed a net predation success rate on par with other adult vertebrates. Conversely, C. trilineatus successfully avoided predation by orienting predator attacks toward their resilient, axial armor and behavioral strategies that reduced the predator's ability to bite in less armored regions of the body.

Spatial Venomics─Cobra Venom System Reveals Spatial Differentiation of Snake Toxins by Mass Spectrometry Imaging.

Among venomous animals, toxic secretions have evolved as biochemical weapons associated with various highly specialized delivery systems on many occasions. Despite extensive research, there is still limited knowledge of the functional biology of most animal toxins, including their venom production and storage, as well as the morphological structures within sophisticated venom producing tissues that might underpin venom modulation. Here, we report on the spatial exploration of a snake venom gland system by matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI), in combination with standard proteotranscriptomic approaches, to enable in situ toxin mapping in spatial intensity maps across a venom gland sourced from the Egyptian cobra (Naja haje). MALDI-MSI toxin visualization on the elapid venom gland reveals a high spatial heterogeneity of different toxin classes at the proteoform level, which may be the result of physiological constraints on venom production and/or storage that reflects the potential for venom modulation under diverse stimuli.

Meta-analysis of tadpole taste tests: consumption of anuran prey across development and predator strategies.

The risk of predation and the costs and benefits of diverse anti-predator strategies can shift across the life stages of an organism. Yet, empirical examples of ontogenetic switches in defense mechanisms are scarce. Anurans represent an alleged exception; previous meta-analytic work suggests that unpalatability of developing anurans is "rare", whereas adult anurans in many lineages are well defended by toxic and/or unpalatable skin secretions. Here, we revisit the question of the unpalatability of anuran young in a meta-analysis of the relative proportion of prey consumed within 922 predation tests, including 135 anuran species. We tested the hypotheses that a predator's propensity to consume anuran young depends on (1) prey family, (2) predator manipulation strategy, and (3) prey ontogenetic stage. We used a binomial mixed model approach with considerations for multiple effect sizes within studies to evaluate the log odds ratio of the proportion of prey consumed by individual predators. Prey consumption was highly variable, but toads (Bufonidae) were consumed in lower proportions. Chewing invertebrates consumed more anuran prey than biting vertebrates. Late stage tadpoles were more vulnerable to predation than other stages of anuran ontogeny. However, more studies are needed to unravel the roles of development and evolutionary history in the chemical ecology of anuran young. This synthesis provides clear meta-analytic evidence that relative unpalatability is an important component in the anti-predator defenses of young in some anuran families, calling into question the degree to which chemically defended anuran families undergo ontogenetic switches in anti-predator strategies.

Evolution, Expression Patterns, and Distribution of Novel Ribbon Worm Predatory and Defensive Toxins.

Ribbon worms are active predators that use an eversible proboscis to inject venom into their prey and defend themselves with toxic epidermal secretions. Previous work on nemertean venom has largely focused on just a few species and has not investigated the different predatory and defensive secretions in detail. Consequently, our understanding of the composition and evolution of ribbon worm venoms is still very limited. Here, we present a comparative study of nemertean venom combining RNA-seq differential gene expression analyses of venom-producing tissues, tandem mass spectrometry-based proteomics of toxic secretions, and mass spectrometry imaging of proboscis sections, to shed light onto the composition and evolution of predatory and defensive toxic secretions in Antarctonemertes valida. Our analyses reveal a wide diversity of putative defensive and predatory toxins with tissue-specific gene expression patterns and restricted distributions to the mucus and proboscis proteomes respectively, suggesting that ribbon worms produce distinct toxin cocktails for predation and defense. Our results also highlight the presence of numerous lineage-specific toxins, indicating that venom evolution is highly divergent across nemerteans, producing toxin cocktails that might be finely tuned to subdue different prey. Our data also suggest that the hoplonemertean proboscis is a highly specialized predatory organ that seems to be involved in a variety of biological functions besides predation, including secretion and sensory perception. Overall, our results advance our knowledge into the diversity and evolution of nemertean venoms and highlight the importance of combining different types of data to characterize toxin composition in understudied venomous organisms.

Deoxybuzonamine Isomers from the Millipede Brachycybe lecontii (Platydesmida: Andrognathidae)

Millipedes (Diplopoda) are well known for their toxic or repellent defensive secretions. Here, we describe (6aR,10aS,10bR)-8,8-dimethyldodecahydropyrrolo[2,1-a]isoquinoline [trans-anti-trans-deoxybuzonamine (1a)] and (rel-6aR,10aR,10bR)-8,8-dimethyldodecahydropyrrolo[2,1-a]isoquinoline [trans-syn-cis-deoxybuzonamine (1b)], two isomers of deoxybuzonamine found in the chemical defense secretions of the millipede Brachycybe lecontii Wood (Colobognatha, Platydesmida, Andrognathidae). The carbon-nitrogen skeleton of these compounds was determined from their MS and GC-FTIR spectra obtained from the MeOH extract of whole millipedes, along with a subsequent selective synthesis. Their structures were established from their 1D (1H, 13C) and 2D NMR (COSY, NOESY, multiplicity-edited HSQC, HSQC-TOCSY, HMBC) spectra. Additionally, computational chemistry (DFT and DP4) was used to identify the relative configurations of 1a and 1b by comparing predicted 13C data to their experimental values, and the absolute configuration of 1a was determined by comparing its experimental specific rotation with that of the computationally calculated value. This is the first report of dodecahydropyrrolo[2,1-a]isoquinoline alkaloids from a platydesmidan millipede.

Reproductive behaviour, cutaneous morphology, and skin secretion analysis in the anuran Dermatonotus muelleri

SummaryDespite the common poison and mucous glands, some amphibian groups have differentiated glands associated with reproduction and usually present on the male ventral surface. Known as breeding glands or sexually dimorphic skin glands (SDSGs), they are related to intraspecific chemical communication during mating. Until recently, reproduction associated with skin glands was recognized only in salamanders and caecilians and remained unexplored among anurans. The Brazilian microhylid Dermatonotus muelleri (Muller's termite frog) is known for its very toxic skin secretion. Despite the slippery body, the male adheres to the female back during reproduction, as they have differentiated ventral glands. In this paper, we have gathered data proposing an integrative approach correlated with the species' biology and biochemical properties of their skin secretions. Furthermore, we suggest that the adhesion phenomenon is related to arm shortening and rounded body that make amplexus inefficient, although constituting important adaptive factors to life underground.

Comparative transcriptomes of three different skin sites for the Asiatic toad (Bufo gargarizans).

Toads release toxic dry secretions from glands in their skin. Toxin possesses a wide range of biological effects, but little is known about its specific gene expression pattern and regulatory mechanisms. The Asiatic toad (Bufo gargarizans) is widely used to produce toxin. Here, we explored the gene expression of 30 tissue samples from three different skin sites (parotoid gland, dorsal skin, and abdomen skin) of B. gargarizans. After de novo assembly, 783,130 unigenes with an average length of 489 bp (N50 = 556 bp) were obtained. A total of 9,248 significant differentially expressed genes (DEGs) were detected. There were 8,819 DEGs between the parotoid gland and abdomen skin and 1,299 DEGs between the dorsal skin and abdomen skin, while only 1,283 DEGs were obtained between the parotoid gland and dorsal skin. Through enrichment analysis, it was found that the detected differential gene expressions corresponded to the different functions of different skin sites. Our key findings were the genetic expression of toxin secretion, the protection function of skin, and the related genes such as HSD3B, Cyp2c, and CAT, LGALS9. In conclusion, we provide useful transcript resources to study the gene expression and gene function of B. gargarizans and other amphibians. The detected DEGs between different sites of the skin provided better insights into the genetic mechanisms of toxin secretion and the protection function of skin for amphibians.

Representations of the use of psychoactive substances in the beliefs and rituals of ancient societies: between the sacred and the profane

The use of plants with psychoactive properties by ancient communities has been confirmed in numerous archaeological studies conducted in almost every place on earth. Many tribes used their own characteristic psychoactive potions and, according to researchers, their use fostered the integration of the members of a given community, facilitated their existence in an occupied area and could be of significant importance for its survival. Around the psychoactive plants and toxic secretions of some species of fauna a conglomerate of myths, cults and the properties attributed to them has developed. Permanent traces of their presence remain in both non-material and material culture. The aim of this article is to present the representations of psychoactive substances in the beliefs of ancient communities, their occurrence in myths, rock or sepulchral art, and to discuss the reasons for their use during rituals. The article presents also the main causes of the diffusion of the use of psychoactive plants from the sacred to the profane sphere.

Some aspects of toxic secretions accumulation in mammalian organisms

А qualitative method was used in the study. The article describes the terrain of the studied territories, the heterogeneity of the biotic component, the description of the aspects of the accumulation of toxic excretions on mammalian organisms.During the investigation, the main environmental pollutants in the Pavlodar region and their impact on the organisms of mammals were studied. Catching of animals is carried out according to standard methods using accounting lines: trap-lines and trapping grooves. The aspects of bioaccumulation of fluorine, benz (a) pyrene, heavy metals (lead, zinc, arsenic, mercury) in the organisms of animal populations inhabiting the urban areas of Pavlodar region have been determined. The main fluoride depot is bone tissue. Heavy metals tend to accumulate in the fur of mammals, as well as in the liver, kidneys, lungs and genitals. The most dangerous for animal health is benzo (a) pyrene, which can accumulate in adipose tissue. Benz (a) pyrene, being the strongest mutagen, can lead to the formation of malignant tumors. The degree of accumulation of toxic secretions directly depends on the habitat of animals and the type of food. It was found that contaminants can accumulate in bone, connective and epithelial tissues.

Increased Caspase-3 Immunoexpression and Morphology Alterations in Oenocytes and Trophocytes of Apis mellifera Larvae Induced by Toxic Secretion of Epormenis cestri

Abstract Toxic honeydew produced by Flatidae Epormenis cestri in Uruguay has been shown to cause among honeybees (Apis mellifera) colonies a massive larva death called “River disease”, but the intrinsic mechanisms are still unknown. Because fat body cells, oenocytes and trophocytes, are known to regulated larvae metabolism, and to be affected by xenobiotics, we tested whether apoptosis of these cells can be an underlying cause of larvae death. Ten colonies were divided into two groups and fed with common honey or toxic honeydew obtained from colonies affected by “River disease”. Five-dayold larvae were collected and processed for histology and immunohistochemistry for caspase-3. The area, diameter, and immunostaining area in oenocytes and trophocytes were measured. The oenocyte and trophocyte cellular area decreased in the treated group (p=0.002; p<0.001 respectively) compared to the control group. The diameter of oenocytes (p=0.0002) and trophocytes (p<0.0001) decreased in the treated group. Caspase-3 was detected in cytoplasm in the control group but in the cytoplasm and nucleus in the treated group. The caspase-3 immunostaining area increased in oenocytes (p<0.002) and trophocytes (p<0.0001) of the treated group. The ingestion of toxic honeydew altered the morphology, localization and immunoexpression of caspase-3 in fat body cells, which suggests that the deregulation of the apoptotic mechanism affected the normal development in A. mellifera larvae.

Cell-Penetrating Peptides Derived from Animal Venoms and Toxins.

Cell-penetrating peptides (CPPs) comprise a class of short polypeptides that possess the ability to selectively interact with the cytoplasmic membrane of certain cell types, translocate across plasma membranes and accumulate in the cell cytoplasm, organelles (e.g., the nucleus and mitochondria) and other subcellular compartments. CPPs are either of natural origin or de novo designed and synthesized from segments and patches of larger proteins or designed by algorithms. With such intrinsic properties, along with membrane permeation, translocation and cellular uptake properties, CPPs can intracellularly convey diverse substances and nanomaterials, such as hydrophilic organic compounds and drugs, macromolecules (nucleic acids and proteins), nanoparticles (nanocrystals and polyplexes), metals and radionuclides, which can be covalently attached via CPP N- and C-terminals or through preparation of CPP complexes. A cumulative number of studies on animal toxins, primarily isolated from the venom of arthropods and snakes, have revealed the cell-penetrating activities of venom peptides and toxins, which can be harnessed for application in biomedicine and pharmaceutical biotechnology. In this review, I aimed to collate examples of peptides from animal venoms and toxic secretions that possess the ability to penetrate diverse types of cells. These venom CPPs have been chemically or structurally modified to enhance cell selectivity, bioavailability and a range of target applications. Herein, examples are listed and discussed, including cysteine-stabilized and linear, α-helical peptides, with cationic and amphipathic character, from the venom of insects (e.g., melittin, anoplin, mastoparans), arachnids (latarcin, lycosin, chlorotoxin, maurocalcine/imperatoxin homologs and wasabi receptor toxin), fish (pardaxins), amphibian (bombesin) and snakes (crotamine and cathelicidins).

The Insecticidal Activity of Rhinella schneideri (Werner, 1894) Paratoid Secretion in Nauphoeta cinerea Cocroaches.

Rhinella schneideri is a common toad found in South America, whose paratoid toxic secretion has never been explored as an insecticide. In order to evaluate its insecticidal potential, Nauphoeta cinerea cockroaches were used as an experimental model in biochemical, physiological and behavioral procedures. Lethality assays with Rhinella schneideri paratoid secretion (RSPS) determined the LD50 value after 24 h (58.07µg/g) and 48 h exposure (44.07 µg/g) (R2 = 0.882 and 0.954, respectively). Acetylcholinesterase activity (AChE) after RSPS at its highest dose promoted an enzyme inhibition of 40%, a similar effect observed with neostigmine administration (p < 0.001, n= 5). Insect locomotion recordings revealed that RSPS decreased the distance traveled by up to 37% with a concomitant 85% increase in immobile episodes (p < 0.001, n = 36). RSPS added to in vivo cockroach semi-isolated heart preparation promoted an irreversible and dose dependent decrease in heart rate, showing a complete failure after 30 min recording (p < 0.001, n ≥ 6). In addition, RSPS into nerve-muscle preparations induced a dose-dependent neuromuscular blockade, reaching a total blockage at 70 min at the highest dose applied (p < 0.001, n ≥ 6). The effect of RSPS on spontaneous sensorial action potentials was characterized by an increase in the number of spikes 61% (p < 0.01). Meanwhile, there was 42% decrease in the mean area of those potentials (p < 0.05, n ≥ 6). The results obtained here highlight the potential insecticidal relevance of RSPS and its potential biotechnological application.

Gosodesmine, a 7-Substituted Hexahydroindolizine from the Millipede Gosodesmus claremontus.

Millipedes (Diplopoda) are well known for their toxic or repellent defensive secretions. Here we describe gosodesmine (1), 7-(4-methylpent-3-en-1-yl)-1,2,3,5,8,8a-hexahydroindolizine, a unique alkaloid with some terpene character found in the chemical defense secretions of the millipede Gosodesmus claremontus Chamberlin (Colobognatha, Platydesmida, Andrognathidae). The structure of 1 was suggested by its mass spectra and GC-FTIR spectra and established from its 1H, 13C, and 2D NMR spectra and 1D NOE studies. The 7-substituted indolizidine carbon skeleton of 1 was confirmed by unambiguous synthesis. This is the first report of an alkaloid from a platydesmid millipede and the first report of a 7-substituted indolizidine from an arthropod.

Behavioral, Physiological, Demographic and Ecological Impacts of Hematophagous and Endoparasitic Insects on an Arctic Ungulate.

Animals that deliver a toxic secretion through a wound or to the body surface without a wound are considered venomous and toxungenous, respectively. Hematophagous insects, such as mosquitoes (Aedes spp.), meet the criteria for venomous, and some endoparasitic insects, such as warble flies (Hypoderma tarandi), satisfy the definition for toxungenous. The impacts of these insects on their hosts are wide ranging. In the Arctic, their primary host is the most abundant ungulate, the caribou (Rangifer tarandus). The most conspicuous impacts of these insects on caribou are behavioral. Caribou increase their movements during peak insect harassment, evading and running away from these parasites. These behavioral responses scale up to physiological effects as caribou move to less productive habitats to reduce harassment which increases energetic costs due to locomotion, reduces nutrient intake due to less time spent foraging, and can lead to poorer physiological condition. Reduced physiological condition can lead to lower reproductive output and even higher mortality rates, with the potential to ultimately affect caribou demographics. Caribou affect all trophic levels in the Arctic and the processes that connect them, thus altering caribou demographics could impact the ecology of the region. Broadening the definitions of venomous and toxungenous animals to include hematophagous and endoparasitic insects should not only generate productive collaborations among toxinologists and parasitologists, but will also lead to a deeper understanding of the ecology of toxic secretions and their widespread influence.

Correction to: Predation of treefrogs (Anura: Hylidae) with toxic skin secretions by the black lion tamarin (Leontopithecus chrysopygus, Callitrichinae).

In the original publication of the article, the scientific name of veined treefrog.

Venom Collection from Spiders and Snakes: Voluntary and Involuntary Extractions ("Milking") and Venom Gland Extractions.

Venom collection (often called "milking") provides the toxic secretions essential for studying animal venoms and/or generating venom products. Methods of venom collection vary widely, falling into three broad categories: voluntary venom extraction (inducing the animal to willingly release its venom), involuntary venom extraction (glandular massage, electrical stimulation, or administration of induction chemicals to promote venom expulsion), and venom gland extraction (surgical aspiration or trituration of homogenized gland tissue). Choice of method requires consideration of animal species, animal welfare, human safety (avoiding envenomation), venom yield and composition desired, and level of toxin purity required. Here, we summarize the materials and methods used to obtain venom by each of these approaches from spiders and snakes.