<P> These snakes can go for up to two years without food in the wild . A 51⁄2 - month starvation study showed the snakes reduced energy expenditures by an average of 80% over the length of the study . The snakes also feed from within on energy - rich lipid stores . The most interesting finding was the snakes grew during the study, indicating while the snake's mass was shrinking, it was putting its resources into skeletal muscles and bone . </P> <P> A key participant in the food chain, it is an important predator of many small rodents, rabbits, and birds . In turn, it is preyed upon by a variety of larger mammals and birds, such as coyotes, foxes, hawks, and owls . Crotalus atrox can be active at any time of the day or night when conditions are favorable . It is primarily diurnal and crepuscular in spring and fall and becomes primarily nocturnal and crepuscular during the hot summer months . </P> <P> Like most other American pit vipers, the venom contains proteolytic enzymes . Proteolytic venoms are concentrated secretions that destroy tissues as a result of catabolism of structural and other proteins, which help in disabling prey . The venom of C. atrox is primarily hemotoxic, affecting mainly the blood vessels, blood cells and the heart . The venom contains hemorrhagic components called zinc metalloproteinases . The venom also contains cytotoxins and myotoxins which destroy cells and muscles that add to the failure of the cardiovascular system . In addition to hemorrhage, venom metalloproteinases induce myonecrosis (skeletal muscle damage), which seems to be secondary to the ischemia that ensues in muscle tissue as a consequence of bleeding and reduced perfusion . Microvascular disruption by metalloproteinases also impairs skeletal muscle regeneration, being therefore responsible for fibrosis and permanent tissue loss after bites from this species . General local effects include pain, heavy internal bleeding, severe swelling, severe muscle damage, bruising, blistering, and necrosis; systemic effects are variable and not specific, but may include headache, nausea, vomiting, abdominal pain, diarrhea, dizziness, and convulsions . Hemorrhagins causing bleeding is a major clinical effectthis can lead to death and sickness . </P> <P> This species has LD values of 2.72 mg / kg intravenous, 20 mg / kg intramuscular and 18.5 mg / kg subcutaneous, which is far less toxic than many other rattlesnakes . However, because of its large venom glands and specialized fangs, the western diamondback rattlesnake can deliver a significant amount of venom in a single bite . The average venom yield per bite is usually between 250 and 350 mg, with a maximum of 700--800 mg . Severe envenomation is rare, but possible, and can be lethal . Mortality rate of untreated bites is between 10 and 20% . </P>

What kind of venom does a diamondback rattlesnake have
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