Pit Viper Envenomation in Two Pregnant Bitches.

Snake envenomation is relatively common in small animals, particularly in endemic areas. Effects and outcomes of envenomation during pregnancy are poorly described in humans and more so in veterinary patients. Two young pregnant female dogs presented to a university teaching hospital with a history of acute soft tissue swelling and bleeding. History, physical examination findings, and diagnostics were consistent with envenomation by crotalid snakes. Medical management of one of the dogs included administration of antivenin. Both dogs survived envenomation with minimal complications and went on to whelp without complications, and all fetuses survived. This is the first description of the management of pit viper envenomation in pregnant dogs.

Snake Envenomation.

Snakebite envenomation (SBE) in horses can have devastating outcomes. Tissue damage, cardiotoxicity, coagulopathy, and neurotoxicity can be concerns with SBE. Understanding the actions of venom components is important in developing a successful treatment plan. Antivenom is the mainstay of treatment. Long-term deleterious effects can occur including cardiac dysfunction and lameness.

The challenge in detecting risk areas of snakebite when case rates are low: the case of Amazonian coral snakes.

Identifying risk areas for envenomation by animals is relevant for public health, such as strategic distribution of antivenoms. Coral snakes are highly diverse in the Amazon, inhabit natural and human-modified environments, and the outcome of the cases tends to be serious and potentially lethal due to their neurotoxic venom. By integrating species' geographical records and environmental variables, we used species distribution modeling to predict the distribution of coral snake species in the Brazilian Amazonia. We analyzed the relationship between the predicted distribution of coral snake species, along with envenomation data in the region, to propose actions to reduce the number of cases and to provide tools for a better policy of public health. We conclude that the entire Amazon shows high environmental suitability for coral snakes, and such suitability explains little about the incidence of cases. This is probably due to the low human density in the Amazon and to coral snake traits such as secretive habits and non-agressive behavior. Differently from other venomous snakes, the scenario regarding coral snakebites precludes the detection of prominent geographical areas of concern and demands a broad and equitable availability of health centers throughout Amazonia and along other areas of occurrence of the genus Micrurus.

Snakebite Envenoming in Avian Species: A Systematic Scoping Review and Practitioner Experience Survey.

Snakebite envenoming in avian species is infrequently reported in the veterinary literature, although perhaps not as rarely as recent publications suggest. A systematic scoping review was performed on the topic using PubMed and Google Scholar, 21 veterinary textbooks, and 139 conference proceedings. A practitioner experience survey was also performed, with recruitment from Facebook groups for exotic animal practitioners and professional organization email listservs. Only 31 texts met our inclusion/exclusion criteria, which meant they described clinicopathologic signs of snakebite envenomation in avian species, the treatment of snakebite envenomation in avian species, or expanded the geographic range or the number of captive avian and snake species involved. Reports included approximately 15-20 different species of both snakes and birds worldwide; however, no reports described clinicopathologic signs of naturally occurring snakebites from Asia, Australasia, or Europe. The few responses from our practitioner experience survey suggest that snakebite envenomation may be more common than previously reported. Clinical signs of snake envenomation in birds appear to depend on the snake species involved but often include local swelling and subcutaneous edema or hemorrhage with paired fang marks; weakness, bleeding, neurologic deficits, and death may follow. A wide variety of treatment protocols have been used to counter snakebite envenomation in birds, including the successful use of antivenom. Based on this body of evidence, much remains to be learned about snakebite envenomation of birds, particularly about the efficacy of different treatment protocols.

Crotalid Polyvalent F(ab)2 Antivenom Treatment in a Red-Tailed Hawk (Buteo jamaicensis).

Envenomation in avian species can result in death, with few cases of successful treatment described. A juvenile, wild-caught, intact female red-tailed hawk (Buteo jamaicensis) used in falconry was presented for emergency evaluation after being bitten by a Northern Pacific rattlesnake (Crotalus oreganus) approximately 2 hours before presentation. On presentation, the bird was quiet, alert, and responsive, with moderate swelling and discomfort of the digits on the right foot. Complete blood count (CBC) and plasma biochemistry abnormalities included a regenerative left shift, severe lymphopenia, and a moderate hypoproteinemia characterized by moderate hypoalbuminemia. Analgesic and antibiotic medications were administered during hospitalization. In addition, 5 mL of VenomVet was administered intravenously with crystalloid fluids over 60 minutes; no adverse effects were noted secondary to infusion. Improvement in the swelling was observed immediately after antivenom administration and nearly resolved within 12 hours. Complete resolution of digital swelling with no discomfort on palpation of that foot was observed 1 week after initial presentation. Blood collected at the 1 week reexamination was submitted for a CBC and plasma biochemistry panel. The results of the CBC revealed a reduced regenerative left shift, increased heterophil count, and a moderate monocytosis; the lymphopenia was resolved. A mild hypoalbuminemia still persisted. Ten months after presentation, the bird was reported to be doing well with no changes in function of the right foot and subsequently released from captivity.

Serial serum creatinine, SDMA and urinary acute kidney injury biomarker measurements in dogs envenomated by the European adder (Vipera berus).

BACKGROUND: Acute kidney injury (AKI) is associated with high morbidity and mortality in dogs, but diagnosis may be impaired due the insensitivity of routine renal function biomarkers to detect earlier or milder forms of injury. Snake envenomation is one of several causes of AKI in dogs and humans. Dogs are commonly envenomated by the European adder (Vipera berus) between April and October each year, but few studies exist examining serial serum creatinine (sCr) and symmetric dimethylarginine (SDMA) measurements and AKI biomarkers in these dogs. Novel urinary biomarkers could improve clinical outcome by allowing earlier diagnosis of and intervention in AKI. The aim of this study was to assess the presence of AKI in dogs envenomated by V. berus at 12, 24 and 36 h after bite, as well as 14 days later, using sCr, SDMA and a panel of urinary AKI biomarkers normalised to urine creatinine (uCr), compared to a group of healthy control dogs. RESULTS: Thirty-five envenomated dogs and 35 control dogs were included. Serum creatinine did not exceed the upper reference limit at any time point in any dog after envenomation. Serum SDMA did not exceed 0.89 µmol/L in any dog. Compared to controls, urinary albumin/uCr, neutrophil gelatinase-associated lipocalin/uCr and monocyte chemotactic protein-1/uCr were significantly elevated 12 h (P <  0.0001, P <  0.0001, P = 0.01), 24 h (P <  0.001, P <  0.001, P = 0.002) and 36 h (P <  0.001, P <  0.001, P = 0.0008) after bite. Osteopontin/uCr was higher 24 and 36 h after bite (P < 0.0001), kidney injury molecule-1/uCr, interleukin-8/uCr and γ- glutamyl transferase/uCr were significantly higher 36 h after bite (P = 0.003, P = 0.0005, P = 0.001). Urinary cystatin C/uCr was not significantly different to controls at any timepoint. Biomarker/uCr ratios were not significantly different 14 days after envenomation compared to controls. CONCLUSION: Urinary biomarker/Cr ratios are indicative of mild transient, non-azotaemic AKI in dogs envenomated by V. berus.

Ultrasonography of sudden swollen tongue in a calf.

BACKGROUND: In cattle, the lingual diseases are primarily diagnosed postmortem by histopathological examination of the affected tongues obtained after the death or during necropsy. In humans, ultrasonography has been used to provide differential diagnoses, and for preoperative or intraoperative planning of glossectomy in various lingual diseases. This is a bovine clinical case report, in which ultrasonography for sudden swelling of the tongue, which was possibly caused by snake bite, was utilized as a preoperative indication to perform a glossectomy. CASE PRESENTATION: An eight-month-old female Japanese black calf presented with sudden swelling of the tongue with well-defined discoloration in the cranial region. A 10-MHz linear probe on a portable-type ultrasound machine (MyLabOne VET, Esaote Co., Genova, Italy) was applied to the ventral surface of the tongues in the affected case, and also in five healthy calves under sedation to observe normal tongues. Ultrasonography of the swollen tongue in this case revealed that the ventral lingual muscular layers were severely thickened compared with those of normal tongues. However, the muscle layers were regularly aligned with the echogenic muscular fibers. This resembled the lingual muscular architectures of normal tongues. Color-flow Doppler ultrasonography revealed that blood flow was weakened in the small peripheral vessels in the spaces between the lingual muscular structures, and was lacking in the deep lingual artery between the apex and base of the tongue. This finding was very different than that of normal tongues, which exhibited weakened or rich blood flows. Based on ultrasonographic findings, this case was treated with glossectomy. After recovery, the calf grew up normally with a normal appetite and rumination, and did not exhibit mouth pain behavior. Histopathologically, hemorrhagic necrotic changes, together with focal formation of fibrin thrombus in the lingual blood vessels in the affected tongue, were noted. CONCLUSIONS: To the best of our knowledge, the present report is the first description of lingual ultrasonography performed in cattle. In this case, ultrasonography enabled visualization of decreased vascularity, which might be associated with hemorrhage or formation of fibrin thrombus in the suddenly swollen tongue presented.

Transient Megaesophagus Following Coral Snake Envenomation in Three Dogs (2013-2018).

A 12 yr old dachshund, a 7 yr old English springer spaniel, and a 1.5 yr old French bulldog presented following envenomation by a coral snake. Each patient displayed evidence of varying degrees of lower motor neuron dysfunction, but all three developed transient megaesophagus. Two patients developed secondary aspiration pneumonia, with one requiring mechanical ventilation, which the owners declined, resulting in euthanasia. The third developed hypoventilation without aspiration pneumonia, was mechanically ventilated, and was successfully weaned. In the two surviving patients, the megaesophagus resolved by time of discharge. Coral snake envenomation is an uncommon occurrence, and these are the first documented cases of transient megaesophagus secondary to a North American species.

Clinical, hematobiochemical, and pathological findings and therapeutic management of viperine snake envenomation in zebu cattle.

The present investigation was carried out to study the epidemiology, clinical signs, bleeding profile, kidney function, and pathology and to evaluate the therapeutic protocol for viperine snake envenomation in zebu cattle over a period of 14 years. A total of 98 cases of viperine bite were reported with the highest incidence during monsoon months in grazing male zebu cattle. Ascending swelling over the affected limb with lameness or asymmetrical swelling over the face with dyspnea was a consistent clinical finding. Increased bleeding tendency was invariably observed in ailing cattle with major bleeding from the site of the bite. Hematobiochemistry showed neutrophilic leukocytosis, thrombocytopenia, prolonged capillary blood clotting time, and elevation of BUN and creatinine. The characteristic gross pathological lesions observed were widespread petechial to ecchymotic hemorrhages in the lungs, liver, heart, spleen, abomasal mucosa, and intramuscular or subcutaneously at the site of bite. Histopathological examination revealed presence of necrohemorrhagic changes within the liver, heart, kidneys, skeletal muscles, and subcutaneously or intradermally at the site of bite. Diagnosis of viperine snakebite was made based on circumstantial evidence of bite, progressive swelling, and bleeding at the site of bite. The severity was assessed based on prolongation of capillary blood clotting time, thrombocytopenia, and kidney dysfunction. Therapeutic protocol comprising polyvalent anti-snake venom along with supportive therapy for 5-9 days showed encouraging results with 88.30% survival rate. In conclusion, the precise diagnosis of viperine snake envenomation in cattle can be made from history and typical clinical signs while severity and treatment can be monitored based on bleeding profile.

Canine ocular and periocular snakebites requiring enucleation: A report of 19 cases.

PURPOSE: To describe the clinical and histopathologic features secondary to ocular and periocular snakebites in dogs requiring enucleation. METHODS: Retrospective review of patients with recorded snakebite envenomation from the archives of the Comparative Ocular Pathology Laboratory of Wisconsin (COPLOW) and Texas A&M Veterinary Medical Teaching Hospital (1997-2017). The cases included in this study required witnessed snakebites to the dog by the owner, clinical signs supportive of periocular or ocular envenomation, and/or histopathologic lesions compatible with snakebites. Two groups were established: ocular bites (OB) and periocular bites (PB). RESULTS: Nineteen cases were included in the study (OB = 16/19; PB = 3/19). Dogs affected were typically older (median 8 years; range 1-18), and both sexes were equally represented. Left eyes (14/19) were more likely to sustain snake-induced trauma compared to right eyes (5/19). Fifteen breeds were identified, with terriers (9/19) commonly represented. Snakes bites occurred in six US states, with the majority of cases from Texas (7/19), California (5/19), and Arizona (4/19). Common clinical signs included facial edema, corneal ulceration, keratomalacia, uveitis, hyphema, and secondary glaucoma. All eyes demonstrated vision loss prior to enucleation. Histologically, the ocular and periocular tissues contained extensive necrosis associated with envenomation. Retinal detachment, lens capsule rupture, and intraocular hemorrhage/inflammation were commonly found. CONCLUSIONS: Snakebite envenomation is a largely necrotizing disease process that can result in profound infiltrative and destructive ocular changes presumed to be related to the proteolytic factors and necrotoxins in venom. Ocular alterations secondary to snakebites may be irreversible regardless of supportive therapy instituted.

THE FIRST REPORT OF A CROTALID ENVENOMATION IN A DOMESTICATED FERRET ( MUSTELA FURO) AND SUCCESSFUL TREATMENT WITH A NOVEL F(AB')2 ANTIVENOM.

A case report of a domesticated ferret ( Mustela furo) envenomated by a presumptive rattlesnake ( Crotalus sp.) treated successfully and safely with the novel Fab (2') North American Snake Antivenom (Veteria Labs). The ferret presented with clinical signs of depressed mentation and facial edema following a rattlesnake ( Crotalus sp.) bite. It developed hypotension, thrombocytopenia, and ecchymosis following the envenomation. It was treated with Fab (2') antivenom and given supportive care including crystalloid fluids and analgesia to resolution of clinical signs. This is the first documented case of rattlesnake envenomation in this species. This case supports the efficacy and short-term safety of this Fab (2') antivenom in this species without the use of antihistamines or glucocorticoids. This report also addresses the current standards of care with thorough review of the literature involving rattlesnake envenomation in zoological species.

Active immunization of cattle with a bothropic toxoid does not abrogate envenomation by Bothrops asper venom, but increases the likelihood of survival.

This study assessed the protective effect of active immunization of cattle to prevent the envenomation induced by B. asper venom. Two groups of oxen were immunized with a bothropic toxoid and challenged by an intramuscular injection of either 10 or 50 mg B. asper venom, to induce moderate or severe envenomations, respectively. Non-immunized oxen were used as controls. It was found that immunized oxen developed local edema similar to those observed in non-immunized animals. However, systemic effects were totally prevented in immunized oxen challenged with 10 mg venom, and therefore antivenom treatment was not required. When immunized oxen were challenged with 50 mg venom, coagulopathy was manifested 3-16 h later than in non-immunized oxen, demonstrating a delay in the onset of systemic envenomation. In these animals, active immunization did not eliminate the need for antivenom treatment, but increased the time lapse in which antivenom administration is still effective. All experimentally envenomed oxen completely recovered after a week following venom injection. Our results suggest that immunization of cattle with a bothropic toxoid prevents the development of systemic effects in moderate envenomations by B. asper, but does not abrogate these effects in severe envenomation.

PRESUMPTIVE PIT VIPER ENVENOMATION IN PSITTACINES IN A BRAZILIAN ZOO.

Snake bites represent a serious public health risk in many regions of the globe, especially in tropical areas. Clinical signs and postmortem changes are well described in human and other mammalian species. However, detailed case reports about venomous snake attacks in avian species are limited. This report describes presumptive fatal envenomations in three psittacines caused by pit vipers in a Brazilian zoo. In one case, a Brazilian lancehead (Bothrops moojeni) was captured in the aviary. In all three cases the dermis around the suspected snake bite area exhibited hemorrhages and edema. Histologically, degeneration and necrosis of subcutaneous musculature were observed. Lung, heart, and kidneys displayed focal hemorrhages. The local changes are similar to those described for mammalian patients including humans. However, except for the parenchymatous hemorrhages, additional external and internal gross and histopathological lesions were missing. After ruling out other causes, such as aggression and dicoumarinic intoxication, the presumptive diagnosis of snake envenomation was made. The smaller size and variabilities of pathophysiological effects of the venom in parrots might explain the different lesion patterns observed, compared with mammals. Possibly, the birds may have reacted differently to envenomation by pit vipers and died before the venom could cause macroscopic and histological changes often observed in mammals.

Ophthalmic abnormalities secondary to periocular or ocular snakebite (pit vipers) in dogs--11 cases (2012-2014).

OBJECTIVE: To describe ophthalmic abnormalities secondary to periocular and ocular snakebite in dogs. ANIMAL STUDIED: Retrospective review of medical records from dogs presenting to the Small Animal Hospital at University of Florida following snakebites to the face (2012-2014). Two groups were identified: periocular bites (PB) and ocular bites (OB). RESULTS: Records from eleven dogs matched the search criteria and were included in the study (PB=9, 81.8%; OB=2, 18.2%). Both OB cases involved the cornea. Facial edema, blepharospasm, chemosis, and conjunctival hyperemia occurred in all cases (100%). Hemorrhage from the eyelids occurred in eight cases (72.7%; PB=7, OB=1). Subconjunctival hemorrhage occurred in seven cases (63.6%; PB=6, OB=1). Third eyelid laceration and nictitans gland prolapse occurred in 1 case each (9%; PB=1). Lagophthalmia was present in three cases (27.3%; PB=3), with secondary corneal ulcer in two cases (18.2%; PB=2). Corneal ulcer due to direct corneal bite occurred in two cases (18.2%-partial thickness with melting (1) and full thickness (1) ). Uveitis was present in 6 cases (54.5%; PB=4, OB=2), with flare and miosis in 4 cases (36.4%; PB=2, OB=2). Hyphema, fibrin in anterior chamber, and cataract occurred in one case (9%; OB=1). Vision loss occurred in two cases (18.2%; PB=2), secondary to retinal degeneration (PB=1) and amaurosis (PB=1). Mean follow-up time was 7 weeks (range: 3 days-11 months). Most clinical signs had resolved by last examination. CONCLUSIONS: Periocular symptoms were more commonly observed than ocular alterations, regardless of bite location. Appropriate supportive therapy should be instituted according to clinical signs.

XENOTRANSFUSION IN AN ISLAND FOX (UROCYON LITTORALIS CLEMENTAE) USING BLOOD FROM A DOMESTIC DOG (CANIS LUPUS FAMILIARIS).

Successful xenotransfusion in an island fox ( Urocyon littoralis clementae) has not been previously reported but may be necessary in an emergency. An 11-yr-old male, intact, captive island fox was exhibiting clinical signs of rattlesnake envenomation including hypoperfusion, tachypnea, facial edema, and multifocal facial and cervical ecchymosis. Blood work revealed severe thrombocytopenia (18 K/µl) and anemia (Hct 15.8%). A presumptive diagnosis of rattlesnake ( Crotalus sp.) envenomation was made. Initial treatment included oxygen therapy, fluid therapy, antibiotics, antacids, pain medications, and polyvalent crotalid anti-venom. Emergency xenotransfusion using whole blood (45 ml) from a domestic dog was used due to worsening clinical signs from anemia. No acute or delayed transfusion reactions were observed in the fox and the patient made a full recovery 5 days later. Successful xenotransfusion in an island fox using whole blood from a domestic dog ( Canis lupus familiaris) is possible and may be lifesaving.

The effect of a single dose of prednisolone in dogs envenomated by Vipera berus--a randomized, double-blind, placebo-controlled clinical trial.

BACKGROUND: Treatment with glucocorticoids after snakebite in dogs is controversial and randomized clinical studies are missing. The objective of this study was to investigate the effect of a single dose of prednisolone in dogs envenomated by Vipera berus in a double-blind placebo-controlled study, after exclusion of dogs treated with antivenom. The two treatment groups were compared regarding clinical status and clinicopathological test results. A total of 75 dogs bitten by Vipera berus within the previous 24 hours were included. Clinical assessment, blood sampling and measurement of the bitten body part were done at admission (Day 1), after 24 hours (Day 2) and at a re-examination (Re-exam) after 10-28 days. Dogs were given prednisolone 1 mg/kg bodyweight (PRED) or saline (PLACEBO) subcutaneously in a randomized, double-blind clinical trial. Dogs were examined clinically and mental status and extent of edema were described. Furthermore, appetite, vomiting, diarrhea, cardiac arrhythmia and death were recorded. Concentrations of C-reactive protein (CRP) and high sensitivity cardiac Troponin I (cTnI), hematology variables and Prothrombin time (PT) were determined. Systemic inflammation was defined as present if CRP > 35 mg/l. RESULTS: None of the dogs died during the study period. The mental status was reduced in 60/75 (80%) of dogs on Day 1, compared to 19/75 (25%) on Day 2. The proportion of dogs with no or only mild edema increased significantly from Day 1 to Day 2. About one-third of the dogs developed gastrointestinal signs during the study period. Cardiac arrhythmia was uncommon. Clinicopathological changes included increased total leucocyte count, CRP and troponin concentration on Day 2. The cTnI concentration was increased in dogs with systemic inflammation, compared to dogs without systemic inflammation. A single dose of prednisolone did not significantly affect any of the clinical or clinicopathological parameters studied, except for a higher monocyte count on Day 2 in dogs that had received prednisolone treatment. CONCLUSION: The results of the present study do not support routine administration of a single dose of prednisolone 1 mg/kg subcutaneously in dogs bitten by Vipera berus.

Comparison of serum amyloid A and C-reactive protein as diagnostic markers of systemic inflammation in dogs.

The diagnostic performance of canine serum amyloid A (SAA) was compared with that of C-reactive protein (CRP) in the detection of systemic inflammation in dogs. Sera from 500 dogs were retrospectively included in the study. C-reactive protein and SAA were measured using validated automated assays. The overlap performance, clinical decision limits, overall diagnostic performance, correlations, and agreement in the clinical classification between these 2 diagnostic markers were compared. Significantly higher concentrations of both proteins were detected in dogs with systemic inflammation (SAA range: 48.75 to > 2700 mg/L; CRP range: 0.4 to 907.4 mg/L) compared to dogs without systemic inflammation (SAA range: 1.06 to 56.4 mg/L; CRP range: 0.07 to 24.7 mg/L). Both proteins were shown to be sensitive and specific markers of systemic inflammation in dogs. Significant correlations and excellent diagnostic agreement were observed between the 2 markers. However, SAA showed a wider range of concentrations and a significantly superior overall diagnostic performance compared with CRP.

Comparaison de la protéine amyloïde sérique A et de la protéine C réactive comme marqueurs diagnostiques de l'inflammation systémique chez les chiens. La performance diagnostique de l'amyloïde sérique canine A (SAA) a été comparée à celle de la protéine C réactive (PCR) dans la détection de l'inflammation systémique chez les chiens. Le sérum de 500 chiens a été inclus rétrospectivement dans l'étude. La protéine C réactive et la SAA ont été mesurées en utilisant des bioanalyses automatisées validées. La performance de chevauchement, les limites de décision cliniques, la performance diagnostique globale, les corrélations et la concordance dans la classification clinique entre ces 2 marqueurs diagnostiques ont été comparés. Des concentrations significativement supérieures des deux protéines ont été détectées chez les chiens avec une inflammation systémique (plage de la SAA : de 48,75 à > 2700 mg/L; plage de la PCR : de 0,4 à 907,4 mg/L) comparativement aux chiens sans inflammation systémique (plage de la SAA : de 1,06 à 56,4 mg/L; plage de la PCR : de 0,07 à 24,7 mg/L). Il a été démontré que les deux protéines étaient sensibles et des marqueurs spécifiques de l'inflammation systémique chez les chiens. Des corrélations significatives et une concordance diagnostique excellente ont été observées entre les deux marqueurs. Cependant, la SAA a indiqué un écart plus vaste pour les concentrations et une performance diagnostique significativement supérieure comparativement à la PCR.(Traduit par Isabelle Vallières).

Evaluation of venom diversity and antivenom quality from the venom of long-term captive vs recently wild captured Pseudocerastes persicus snake: An In vitro and In vivo study.

Snakebite envenomation is a life-threatening condition and antivenoms are used as the most effective treatment. Venom obtained from snakes in long-term captivity showed some variations in comparison to the venom of the wild snakes. The objective of this study is to compare the venom of the Pseudocerastes persicus under long-term captivity and wild conditions as well as the antivenom obtained from these venoms. We have analyzed venom samples and produced trivalent antivenoms using the venom of long-term captive (LTC) or recently wild-captured (RWC) Pseudocerastes persicus, and RWC Macrovipera lebetina, and Echis carinatus. The HPLC analysis revealed that the RWC snakes' venom had three peaks that were not present in the LTC snake's venom. Further analysis using MALDI-TOF and MS/MS showed that the fraction with a retention time (RT) of 14 min contained a toxin from the Kunitz-type serine protease inhibitor (KUT) class, while the fraction with RT 21 a peptide identified within the snake venom metalloproteinase (SVMP) class. The third peak was identified as a sphingolipid. Interestingly, the in vivo preclinical tests showed no significant differences in the effectiveness of the antivenoms. which could be due to the cross-immunogenicity or cross-reactivity between different toxins in the venom. According to our results, small variations in the venom composition of a species do not lead to a decrease in the efficacy of the polyvalent antivenom.

The effects of hyperbaric oxygen therapy on snake-bite-associated wounds in dogs.

OBJECTIVE: To assess the effect of hyperbaric oxygen therapy (HBOT) on Crotalinae envenomation-induced wound swelling and severity and pain in dogs, and to describe the safety and complications of HBOT. DESIGN: Prospective, randomized, controlled, blinded study (2017-2021). SETTING: University teaching hospital, private veterinary practice. ANIMALS: Thirty-six client-owned dogs presenting within 24 hours of a confirmed or suspected naturally occurring Crotalinae snake bite injury were enrolled between 2017 and 2021. INTERVENTIONS: In addition to the standard of care treatment, dogs received 2 interventions with either HBOT (n = 19) or control (n = 16) within 24 hours of hospital admission. Dogs receiving HBOT were pressurized over 15 minutes (1 psi/min), maintained at a target pressure of 2 atmosphere absolute (ATA) for 30 minutes, and decompressed over 15 minutes. Control dogs received 1 ATA for 1 hour. Local wound swelling, wound severity score, and pain score were assessed at admission, before and after each intervention, and at hospital discharge. MEASUREMENTS AND MAIN RESULTS: There was no significant difference in wound swelling (P = 0.414), severity score (P = 1.000), or pain score (P = 0.689) between HBOT and control groups. Pain decreased significantly over time regardless of the study intervention (P < 0.001). There were no major adverse effects associated with either study intervention. CONCLUSIONS: HBOT did not significantly alter the short-term recovery from Crotalinae envenomation in this study population. However, the study might be underpowered to detect a significant treatment effect.

The establishment and evaluation of a swine model of deinagkistrodon acutus snakebite envenomation.

OBJECTIVE: To establish a preclinical large-animal model of Deinagkistrodon acutus snakebite envenomation and evaluate its feasibility. METHODS: The venom of D. acutus (0 mg/kg, 1 mg/kg, 2 mg/kg, 5 mg/kg, or 10 mg/kg) was injected into the left biceps femoris of 11 male pigs. Then, the circumferences of the limbs were regularly measured, and changes in muscle injury biomarkers, blood parameters, coagulation function, vital organ function and injury biomarkers were regularly detected. At 24 h after venom injection, the animals were euthanized, and the pathological damage to the vital organs mentioned above was evaluated. RESULTS: The two pigs receiving 10 mg/kg and 5 mg/kg snake venom died at 8 h and 12 h after injection, respectively. The remaining pigs were equally divided into 0 mg/kg, 1 mg/kg, and 2 mg/kg snake venom groups, and all of them survived to 24 h after injection. Compared with the pigs receiving 0 mg/kg snake venom, the pigs receiving 1 mg/kg or 2 mg/kg snake venom exhibited significant abnormities, including limb swelling; increased muscle injury biomarker creatine kinase (CK) and coagulation function indicators prothrombin time and D-dimer; and decreased blood routine indicator platelet and coagulation function indicator fibrinogen. Moreover, significant abnormalities in myocardial and cerebral function and injury biomarkers in the heart, brain, liver, kidney and intestine were also observed. In particular, the abnormalities mentioned above were significantly obvious in those pigs receiving 2 mg/kg snake venom. Pathological evaluation revealed that the morphology of muscle, heart, brain, liver, kidney, and intestine in those pigs receiving 0 mg/kg snake venom was normal; however, pathological damage was observed in those pigs receiving 1 mg/kg and 2 mg/kg snake venom. Similarly, the pathological damage was more severe in those pigs receiving 2 mg/kg snake venom. CONCLUSION: The intramuscular injection of 2 mg/kg D. acutus venom seems to be an optimal dose for examining the preclinical efficacy of existing and novel therapeutics for treating D. acutus envenomation in pigs.