Snake Venom/Scorpion Venom/Spider venom

About snake venom,scorpion venom and spider venom for sale. please don't hesitate contact me by E mail: snakevenom@126.com Mobile:+86 13116899962

Russell's viper

Basic information:

Chinese name:圆斑蝰蛇
Latin name:Daboia russelii

English name:Russell's viper

Description:

This snake can grow to a maximum length of 166 cm (5.5 ft) and averages about 120 cm (4 ft) on mainland Asian populations, although island populations do not attain this size.It is more slenderly built than most other vipers.[7] Ditmars (1937) reported the following dimensions for a "fair sized adult specimen":

Total length 4 ft., 1 inch 124 cm
Length of tail 7 inches 18 cm
Girth 6 inches 15 cm
Width of head 2 inches 5 cm
Length of head 2 inches 5 cm

The head is flattened, triangular and distinct from the neck. The snout is blunt, rounded and raised. The nostrils are large, in the middle of a large, single nasal scale. The lower edge of the nasal touches the nasorostral. The supranasal has a strong crescent shape and separates the nasal from the nasorostral anteriorly. The rostral is as broad as it is high.

Head of the Russell's viperThe crown of the head is covered with irregular, strongly fragmented scales. The supraocular scales are narrow, single, and separated by 6–9 scales across the head. The eyes are large, flecked with yellow or gold, and each is surrounded by 10–15 circumorbital scales. There are 10–12 supralabials, the 4th and 5th of which are significantly larger. The eye is separated from the supralabials by 3–4 rows of suboculars. There are two pairs of chin shields, the front pair of which are notably enlarged. The two maxillary bones support at least two and at the most five or six pairs of fangs at a time: the first are active and the rest replacements.[5] The fangs attain a length of 16 mm in the average specimen.

The body is stout, the cross-section of which is rounded to cylindrical. The dorsal scales are strongly keeled; only the lower row is smooth. Mid-body, the dorsal scales number 27–33. The ventral scales number 153–180. The anal plate is not divided. The tail is short — about 14% of the total body length — with the paired subcaudals numbering 41–68.

The color pattern consists of a deep yellow, tan or brown ground color, with three series of dark brown spots that run the length of its body. Each of these spots has a black ring around it, the outer border of which is intensified with a rim of white or yellow. The dorsal spots, which usually number 23–30, may grow together, while the side spots may break apart. The head has a pair of distinct dark patches, one on each temple, together with a pinkish, salmon or brownish V or X pattern that forms an apex towards the snout. Behind the eye, there is a dark streak, outlined in white, pink or buff. The venter is white, whitish, yellowish or pinkish, often with an irregular scattering of dark spots.

 

Geographic range

Found in India, Pakistan, Sri Lanka, Bangladesh, Nepal, Myanmar, Thailand, Cambodia, China (Guangxi, Guangdong), Taiwan and Indonesia (Endeh, Flores, east Java, Komodo, Lomblen Islands). The type locality is listed as "India". More specifically, this would be the Coromandel Coast, by inference of Russell (1796).

Brown (1973) mentions that it can also found in Vietnam, Laos and on the Indonesian island of Sumatra.Ditmars (1937) reportedly received a specimen from Sumatra as well.[8] However, the distribution of this species in the Indonesian archipelago is still being elucidated.

Within its range it can be very common in some areas, but scarce in others. In India, is abundant in Punjab, very common along the West Coast and its hills, in southern India and up to Bengal. It is uncommon to rare in the Ganges valley, northern Bengal and Assam. It is prevalent in Myanmar.

 

Venom:

The quantity of venom produced by individual specimens is considerable. Reported venom yields for adult specimens range from 130–250 mg to 150–250 mg to 21–268 mg. For 13 juveniles with an average length of 79 cm, the average venom yield was 8–79 mg (mean 45 mg).

The LD50 in mice, which is used as a possible indicator of snake venom toxicity, is as follows: 0.133 mg/kg intravenous,[25] 0.40 mg/kg intraperitoneal, about 0.75 mg/kg subcutaneous. For most humans, a lethal dose is approximately 40–70 mg. In general, the toxicity depends on a combination of five different venom fractions, each of which is less toxic when tested separately. Venom toxicity and bite symptoms in humans vary within different populations and over time.

Envenomation symptoms begin with pain at the site of the bite, immediately followed by swelling of the affected extremity. Bleeding is a common symptom, especially from the gums and in the urine, and sputum may show signs of blood within 20 minutes post-bite. There is a drop in blood pressure, and the heart rate falls. Blistering occurs at the site of the bite, developing along the affected limb in severe cases. Necrosis is usually superficial and limited to the muscles near the bite, but may be severe in extreme cases. Vomiting and facial swelling occur in about one-third of all cases. Kidney failure (renal failure) also occurs in approximately 25-30 percent of untreated bites. Severe disseminated intravascular coagulation also can occur in severe envenomations. Early medical treatment and early access to antivenom can prevent and drastically reduce the chance of developing the severe/potentially lethal complications.

Severe pain may last for 2–4 weeks. Locally, it may persist depending on the level of tissue damage. Often, local swelling peaks within 48–72 hours, involving both the affected limb and the trunk. If swelling up to the trunk occurs within 1–2 hours, massive envenomation is likely. Discoloration may occur throughout the swollen area as red blood cells and plasma leak into muscle tissue. Death from septicaemia, kidney, respiratory or cardiac failure may occur 1 to 14 days post-bite or even later.

A study in The Lancet journal showed that out of a sample of people bitten by Daboia russelii who survived, 29% of them suffered severe damage to their pituitary glands, which later resulted in hypopituitarism. Other scientific studies support the hypothesis that D. russelii bites can cause hypopituitarism.

Because this venom is so effective at inducing thrombocytopenia, it has been incorporated into an in vitro diagnostic test for blood clotting that is widely used in hospital laboratories. This test is often referred to as Dilute Russell's viper venom time (dRVVT). The coagulant in the venom directly activates factor X, which turns prothrombin into thrombin in the presence of factor V and phospholipid. The venom is diluted to give a clotting time of 23 to 27 seconds and the phospholipid is reduced to make the test extremely sensitive to phospholipid. The dRVVT test is more sensitive than the aPTT test for the detection of lupus anticoagulant (an autoimmune disorder), because it is not influenced by deficiencies in clotting factors VIII, IX or XI.
In India, the Haffkine Institute prepares a polyvalent antivenin that is used to treat bites from this species.

 

Please feel welcome to contact us at snakevenom@126.com should you require any additional information or references.