Venomous snake species can be broadly grouped into three families: Colubridae, Elapidae, and Viperidae. In Portugal, there are four venomous species: the horned viper (Vipera latastei), seoane (Vipera seoanei), rat snake (Malpolon monspessulanus) and the hooded snake (Macroprotodon brevis ibericus), and in the UK the common European adder (Vipera berus). They inoculate the venom through specialised fangs located anteriorly in the maxilla, associated with a venom gland, at high pressure by compression of the gland by skeletal muscle fibres. Snake venom is a complex mixture of toxins whose composition varies depending on the families, genera, species and even subspecies. In Europe, particularly Portugal, there are no published data on the frequency of these types of incidents, but it is estimated to be a high incidence, mostly in dogs. Thus, to characterise the injuries caused by the bite of venom snacks in domestic animals, the authors describe cases in dogs, cats and goats with a suspected snack bite. Animals present wounds compatible with snakebites, and two points 1 to 1.8 cm apart that could be noted in the head or limbs. The main clinical signs observed included pain, oedema and necrosis. From the animals that died the post-mortem examination revealed subcutaneous and muscular necrosis and haemorrhages of surrounding tissues, including muscles and organic haemorrhage.
The severity of envenomation will depend on the quantity of inoculated venom, the species, age, size and previous state of health of the bitten animal, bite location and post-bite excitability. Small animals and young animals may be more susceptible to the effects of venom than larger, healthier animals. Livestock animals may be particularly vulnerable to the effects of venom, as they are often exposed to snakes while grazing in fields or pastures.
With this study, the authors hope to help improve the knowledge regarding snakebites in Europe.