Successful Treatment of a Southern Pacific Rattlesnake (Crotalus viridis helleri) Bite in a Caracal (Caracal caracal)

Abstract

A caracal (Caracal caracal) was bitten on the lower lip by a southern Pacific rattlesnake (Crotalus viridis helleri) and quickly developed progressive, severe soft tissue swelling and bruising of this site. Initial laboratory results revealed prolonged clotting times within the first hour of envenomation, followed by signs of vasculitis and anemia. The caracal was successfully treated with intravenous crystalloids, four vials of polyvalent crotalidae antivenom, and transfusions of bovine hemoglobin glutamer-200 (Oxyglobin) and fresh whole blood. The progressive soft tissue swelling and bruising halted and the coagulation parameters improved after administration of antivenom; however, the caracal continued to show neurologic dysfunction, including depression, weakness, muscle fasciculations, anisocoria, and ataxia. Administration of an additional vial of antivenom 72 hr after envenomation quickly corrected the weakness and muscle fasciculations, whereas the anisocoria and mild ataxia persisted for another 24 hr. The caracal remains clinically normal 3 yr after the envenomation.

Retrospective evaluation of neurotoxic rattlesnake envenomation in dogs and cats: 34 cases (2005–2010)

“…22 Another recent case report describes a caracal envenomated by a Southern Pacific rattlesnake that was initially treated for localized swelling and hemotoxic effects, but later developed ataxia, anisocoria, and muscle fasciculations. 25 Despite the fact that rattlesnake envenomation is a common problem in companion animals in certain areas of the country, neurotoxicity has not been previously documented in these patients aside from a single case report. 21 This may simply mean that the condition has been previously under-recognized, or may be a reflection of the type of snakes found in the areas of previous studies.…”

“…There is 1 case report of a person who developed severe neurotoxicity in addition to local effects of a bite sustained by a snake that was identified as a Southern Pacific rattlesnake . Another recent case report describes a caracal envenomated by a Southern Pacific rattlesnake that was initially treated for localized swelling and hemotoxic effects, but later developed ataxia, anisocoria, and muscle fasciculations . Despite the fact that rattlesnake envenomation is a common problem in companion animals in certain areas of the country, neurotoxicity has not been previously documented in these patients aside from a single case report .…”

Mojave toxin‐type ascending flaccid paralysis after an envenomation by a Southern Pacific Rattlesnake in a dog

“…This case is significant because the snake that envenomated this patient was definitively identified as a Southern Pacific rattlesnake, C. helleri (Figure a and b), a species known to produce hemotoxin . Its venom normally contains protease, l ‐amino oxidase, phospholipase A 2 , and exonuclease, which attacks fibrinogen and facilitates tissue digestion . However, the clinical signs in this patient were more consistent with an envenomation by a Mojave rattlesnake, C. s. scutulatus (Figure d), a species known to produce neurotoxin.…”

“…The geographic region where the envenomation occurred has a documented population of Southern Pacific rattlesnakes with Mojave toxin in their venom . Previous veterinary literature describes a caracal envenomated by a Southern Pacific rattlesnake which developed hemotoxic effects and moderate neurologic signs of weakness, depression, anisocoria, and ataxia . This is the first documented case of a veterinary patient developing ascending flaccid paralysis leading to respiratory failure after being envenomated by a Southern Pacific rattlesnake.…”

Wild Felids Blood Group System

“…A study in Mato Grosso, Brazil, describes that from 211 run overs, 59. were mammals, mostly represented by carnivores, with 52 roadkilled individuals (24% of all roadkilled animals), including some rare or endangered species such as Puma yagouaroundi, Leopardus colocolo, Puma concolor , and ocelot ( Leopardus pardalis ) [ 69 ], but no reports of blood transfusion were found. As far as we know, no erythropoiesis disorders have been described in wild felids, but there has been a report of red blood cells destruction related to a rattlesnake bite in a caracal [ 70 ]. As a major cause of blood transfusion related to hemolytic anemia in domestic cats, erythrocyte parasitism, like hemoplasmosis, babesiosis, or cytauxzoonosis, has also been reported in wild felids [ 71 , 72 , 73 , 74 , 75 , 76 , 77 ], and is sometimes related to anemia [ 71 , 73 , 76 ], but there have been no reports of animals receiving blood transfusions.…”