Snake Venom: Nature, Use and Types | Reptiles

In this article we will discuss about Snake Venom:- 1. Nature of Venom 2. Use of Venom 3. Types.

Nature of Venom:

a. Snake venom is a clear, transparent, pale yellow or straw-coloured fluid having a specific gravity of 1.03-1.07.

b. The pH of the venom varies in different species, e.g., Russell’s viper’s pH is 5.8 and that of cobra venom is 6.6.

c. It is protein in nature containing many enzymes, viz., Proteinase, Hyaluronidase, L-Arginine hydrolases, Transaminase, L-Amino acid oxidase, Phospholipase-A, B and C, Phosphodiesterase, Cholinesterase, Ribonuclease, Deoxyribonuclease, Alkaline phosphatase, Acid phosphatase, Exopeptidases, etc. The composition of venom varies species to species.

d. Most snake venoms are tasteless but cobra venom’s taste is slightly bitter.

e. It is acidic in reaction and soluble in water and glycerine.

f. It is destroyed by coagulating agents like KMnO₄, AgNO₃, as well as alcohol and strong alkalies like NaOH and KOH, etc.

g. The venom also contains metals like Zinc (Zn), Sulphur (S) and Copper (Cu), etc.

h. Venom contains one or more enzymes, several active non-enzymatic proteins having at least two or three peptides.

i. The venom is thermolabile.

j. It can be dried as crystals or lyophilized and dried venom is thermo-stable.

k. It is a good digestive enzyme and can be easily swallowed if there is no wound in the buccal cavity and alimentary canal.

Use of Venom:

Snake venoms are used for treatment of various diseases like epilepsy, asthma, arthri­tis, chronic nervous and muscular pain, neuri­tis, neuralgia, migraine and pain for cancer. Russell viper’s venom can be used as haemo­static agent.

To stop the internal bleeding venom’s dilution can be used. In homeopathy rattle snakes venom is used to cure various diseases like lumbago, sciatica, coccygodynia, laryngitis, pleurisy and insomia, etc.

Types of Snake Venom:

Snake venom is classified into 3 groups according to the nature of action on tissues of human beings.

a. Neurotoxic:

The venom effects mainly on nervous sys­tem. Ultimately the respiration ceases due to failure of nervous system and death occurs. This type of venom occurs in cobras, kraits, mambas and coral snakes. Other species are Taipan (Oxyuranus scullatus). Tiger snake (Notechis scutatus), Death adder (Acanthophis antarcticus) and Tropical rattle snake (Crotalus dwissus).

Neurotoxic envenomation is respon­sible for more than 70% victims of snake bite deaths. In India, out of 10000 snake bite deaths, 5000 are due to cobra bites with 50% mortality and 1700 are due to bites of kraits with 40% mortality. Russell’s viper bites in South India and Sri Lanka have been attri­buted to serious neurotoxicity in addition to coagulopathy.

b. Haemo-toxic:

The venom acts on blood vascular system. Damage is seen to the lining of blood vessels causing hemorrhages. RBC is destroyed cau­sing haemolysis. Clotting of blood occurs, e.g., vipers, and rattle snakes.

c. Myo-toxic:

The venom effects on muscles. This type of venom is seen in sea snakes.

Anti-Snake Venom Serum:

In India anti-snake venom serum is pre­pared at the Haffkine Institute, Bombay and Central Research Institute, Kasauli, Himachal Pradesh. At Haffkine, anti-venom is prepared by immunizing horses.

A mixture of venom of four common poisonous snakes (Cobra, Naja naja; Common Krait, Bungarus caeruleus; Russel’s viper, Vipera russelli and Saw scaled viper, Echis carinatus) is injected into horse’s body and increases its doses gradually. When the horse acquires a certain level of immunity, the plasma is collected by drawing blood from the body. After collection, 10 ml doses are packed.

Anti-venom of Banded krait, King cobra and Sea snake is not produced in India.

Nearest source of anti-venom of Banded Krait and King cobra is the Queen Saovabha Institute, Bangkok, Thailand.

The anti-venom of sea snake (Enhydrina schistosa) is available in Australia and Japan.