Spider Venom Milking Program
Since the inception of the Australian Reptile Park’s funnel-web spider antivenom program in 1981, zero deaths have been recorded due to funnel-web spider. The Australian Reptile Park has played a massive role in this with assistance in the inventing the funnel-web antivenom as well as playing an ongoing role in providing the raw venom to Seqiris for antivenom to be made. The Australian Reptile Park’s venom program houses over 2,000 spiders from baby spiderlings up to full grown adult male specimens; who are milked on a weekly schedule.
How Is Funnel-Web Spider Antivenom Made?
The process of turning venom into antivenom is long and tricky but it’s not impossible. Once the funnel-web spiders have been milked at the Australian Reptile Park, the venom is frozen and sent to Seqiris in Melbourne, Victoria.
The Seqiris team inject very small amounts of the venom into rabbits with the amount increasing in small amounts over a six-month period until the rabbit is able to withstand six-times the lethal dose. Blood is then drawn from the rabbit and the blood is spun in a centrifuge. The spinning separates the antibodies from the blood, and it is these antibodies that make antivenom.
Information About Spider Venom
The venom spiders possess helps them in several ways. It immobilises their prey, begins the process of digestion and is a defence against enemies in the animal kingdom. Venom is a complex mixture of substances, but the toxins are usually only a single substance. Venoms act in different ways and affect different parts of the bite victim. The main types of venom are:
- Neurotoxins: effects the nervous system
- Myotoxins: effects the muscles
- Haemorrhagins: effects the blood vessels and cause bleeding
- Haemotoxins: effects the blood
- Nephrotoxins: effects the kidneys
- Cardiotoxins: effects the heart
- Necrotoxins: effects tissue and cause necrosis
Venom glands are located above the fangs or chelicerae. Venom ducts cross the chelicerae and open near the tips. Venom glands originated as digestive glands, which aided in the external digestion of prey.
Funnel-Web Spider Venom
Although funnel-web spiders are widely distributed throughout the south-eastern Australia, including Tasmania, the only species so far proven to be dangerous to humans are largely limited to the eastern part of New South Wales and southeast Queensland. The only known killer is the Sydney funnel-web spider, which is found mostly in the Sydney region, north to Newcastle and south to the Illawarra region.
The antivenom for the Sydney funnel-web spider has also proved to be effective for various other species of funnel-web. The protein toxin, delta-atraxotoxin, present in the acidic venom is also thought to be the prevalent compound which causes the severe effects in humans. Other mammals seem to be unaffected by the funnel-web spider venom. The toxin produces a rapid effect on the nervous system.
Though there have been 13 recorded deaths from funnel-web spider bites, some cases do not always develop severe symptoms. However, the same precautions first aid should be administered because, if untreated, a major bite may cause death within an hour. First aid treatment involves the application of a pressure-immobilization bandage, the same treatment as applied to a snake bite. The entire affected limb is bandaged firmly and, wherever possible, is further restricted in movement by the application of a splint.
The large fangs and acidic venom make the bite very painful. Bite symptoms start early, beginning with tingling around the mouth, twitching of the tongue, profuse salivating, watery eyes, sweating and muscle spasms. Hypertension and an elevated heartbeat occur which, when combined with respiratory distress may be very severe and potentially lethal.
Red-back Spider Venom
At the Australian Reptile Park we do not milk red-back spiders for venom as the equipment needed is microscopic in size. However, we display them for educational purposes for the public to know more about the species. The antivenom from the red-back spider can also be used to treat bites from the black widow spider. The venom from the female red-back spider is known as a multi-component because it is made up of a family of protein toxins, the latrotoxins being the most prominent. One of these, alpha-latrotoxin, is effective in mammals, including humans, causing over stimulation of neural pathways throughout the body with a wide range of effects. The initial pain of the bite usually means the bite is detected immediately, however; the red-back bite is one of the few spider bites with which antivenom can be effective a few days after the bite occurs.
First aid treatment for red-back bites is different to that for funnel-webs. Do not apply a constrictive bandage. In fact, the only action taken should be to administer ice packs to the bite site to help reduce the pain and then go immediately to hospital.
Only the female red-back spider is dangerous. While the female is large and distinctive with her shiny black body and bright red abdominal stripe (though not all specimens possess this marking), the male red-back is small and insignificant and has a complex pattern including white and, occasionally, yellow markings. As the red back is not a wanderer, most bites occur when the spider’s web has been pulled down or disturbed. Less than 20% of all red-back spider bites actually result in significant envenoming.
Red-back spiders usually make their webs under objects, with droplines to the ground or another flat surface. They are found most commonly under shelves, bottom rails of fence lines, under outdoor furniture, even in cupboards indoors. If you have red backs in your area check thoroughly before putting your hands underneath items such as flowerpot rims, bricks, tables, etc.
