Development of a Treatment Protocol for Cobra (Naja naja) Bite Envenoming in Dogs

Abstract

There is limited information on clinical profiles, treatment, and management aspects of Indian cobra (Naja naja) bite envenoming in dogs in Sri Lanka. Dogs with cobra bites presented to the Veterinary Teaching Hospital (VTH), University of Peradeniya, were prospectively studied over a period of 72 months; local and systemic clinical manifestations and hematological abnormalities were recorded. We studied 116 cobra bite envenomings in dogs. A grading system was established using a combination of anatomical site of fang marks, as well as local and systemic clinical manifestations. Accordingly, treatment strategies were established using Indian polyvalent antivenom (AVS). Pain and swelling at the bite site were major clinical signs observed, while neurotoxic manifestations (mydriasis, wheezing, and crackles) were detected in most dogs. Leukocytosis was observed in 78% of them. Statistical analysis revealed that the grading scores obtained were compatible to initiate AVS administration according to the severity. The minimum number required was 2 AVS vials (range 2–12). Almost 20% of the dogs developed wheezing, crackles, hypersalivation, restlessness, and dyspnea as adverse reactions to AVS treatment. Necrotic wounds on bitten anatomical sites developed in 19% of the dogs and 2.5% developed acute kidney injuries as a consequence of envenoming crisis. Despite treatment, 3% of dogs died. No dry bites were recorded.

Clinico-epidemiology and management of hump-nosed pit viper (Hypnale spp.) bites in dogs

“…dermonecrosis, myonecrosis) 1 , 4 , 15 , 32 . Mild swelling and extensive swelling observed in this study are consistent with the observation of envenoming in dogs due to N. naja in Sri Lanka 21 . Further similarity of varying degrees of swelling, haemorrhagic blisters, local tissue necrosis and regional lymphadenopathy are reported in different studies in human victims of HNPV bite envenoming 1 – 4 , 15 .…”

“…Further similarity of varying degrees of swelling, haemorrhagic blisters, local tissue necrosis and regional lymphadenopathy are reported in different studies in human victims of HNPV bite envenoming 1 – 4 , 15 . Mild and extensive swelling at the site of the bite resolved spontaneously without any adverse outcome as observed in previous studies in both man and animals 21 , 37 . However, to address snakebite-induced local tissue damage and implement wound care, surgical management, including limb amputation on rare situations, had to be employed for HNPV envenomed dogs, as has been necessary for N.naja envenomed dogs 21 .…”

“…Fang marks among the majority of dog victims of N. naja and Dabia russelii 21 , 22 are seen in the head and neck region and a similar bite distribution pattern was seen in the majority of HNPV bitten dogs. Sharp canine teeth have evolved as the major weapons for protection in dogs and they fight facing ahead.…”

“…All the body systems were examined and qualitative and quantitative measurements of the clinical signs and symptoms were recorded. In order to classify the extent of tissue injury/s at the site/s of bite the grading system explained in the studies conducted by Grassi et al, 2016 and Adhikari et al, 2020 were used in this study 21 , 24 . Accordingly, severity of local tissue reactions at the site of bite of the patients were graded.…”

“…Treatment protocols using AVS for Naja naja and Daboia russelii envenoming in dogs have been established recently 21 , 22 . However, detailed investigations beyond several fundamental studies related to HNPV bite envenoming are scarce.…”