This drought year about 3.6 million kangaroos will be shot in the world's biggest wildlife slaughter. It's a small fraction of the total population but we had cause to write to crikey.com.au today about a whole other side to the debate about kangaroos as a source of meat for our population. Their readers are debating climate impacts of ruminants verus kangaroos. But my concern also relates to public health: It revolves around why agriculture was invented in the first place. Keeping food animals free of parasites, with parasites being perhaps the biggest evolutionary force on ...humanity ....ever (that's right, not temperature, not predation, not food availability):
Ever since I did a zoology degree at ANU (which specialises in parasite ecology) I've been wondering about risk profile of wild game meat like kangaroo. Milo Dunphy founder of the Total Environment Centre and a keen hunter in his younger days was against kangaroo as a general food source for this very reason.
The kangaroo meat industry [in our view do not] convincingly address the inevitable, dangerous parasite load in kangaroos unlike farmed animals subject to the usual chemical treatments. Recently on talkback on abc Sydney radio an industry representative [stated] on air ... kangaroos only have worms in the gut not hydatid cysts in the meat. [It seems] hydatid is a seriously under estimated issue, which apparently has gone off the radar. Yet 80 or 90 Australians per year suffer potentially catastrophic consequences of infection via farm dogs getting at wild kangaroos and other infection pathways.
Nor does it help to refer to Indigenous consumption for thousands of years. My advice is traditional folks of the central desert cook the kangaroo meat almost to charcoal to feel safe about eating it. Not exactly your gourmet experience. And we shoot for a much longer life span today.
This report from ABC Landline in 2005, Tapeworm continues to thrive in wild dog population, Reporter: Joanne Shoebridge, First Published: 23/10/2005, http://www.abc.net.au/landline/content/2005/s1486396.htm is a very frightening traverse of hydatid parasites in wild dogs and farm dogs feeding on kangaroo and wallaby carcass, the same kangaroos shot for supermarkets. Crunching into a hydatid in a kangaroo steak could the worst dining experience of your whole life.
The industry says they do inspections under the regulations but the point is farming and chemical treatment to avoid parasites is a far superior prophylactic for high volume food supply which is just not possible in wild kangaroo.
Here is a mild extract of Landline, and think carefully about eating wild meat:
JOANNE SHOEBRIDGE: When he does catch a wild dog, Mark Goullet euthanases them and sends their intestines to the Canberra laboratory of Dr David Jenkins. So far, two in every five dogs tested have been heavily infected with hydatids.
DR DAVID JENKINS: "We are interested from the point of view of, "Are they spreading hydatids in these urban areas?" And the short answer is, "Yes, they are." This is the gut of the dingo or the wild dog in which we're hoping to find tapeworms. And the tapeworms produce the eggs, which then get eaten by a sheep, and each of these cysts represent an egg that the sheep has eaten.
JOANNE SHOEBRIDGE: So you don't get cysts in dogs, you do get cysts in animals like sheep.
DR DAVID JENKINS: That's right. No cysts in dogs. Cysts in sheep, kangaroos, wallabies, but really importantly, this is exactly what happens in people. They don't normally get as many cysts as this, but they will be much, much bigger - maybe 1, 2, 3 litres capacity.
JOANNE SHOEBRIDGE: These dogs, too, are riddled with tapeworms. Hydatid disease is no longer notifiable in most states, which means health authorities have few statistics. David Jenkins has to resort to trawling through the records of individual hospitals to track the incidence of hydatids, which is often poorly diagnosed and recorded.
JOANNE SHOEBRIDGE: Do you think this is a disease that has largely slipped off the radar?
DR DAVID JENKINS: Oh, I'm absolutely sure of it, and not just in the medical profession, in the veterinary profession as well. We get 80 to 100 new cases a year, which in the scheme of things, is not a lot of patients, but nevertheless, for those people who are infected, it can be catastrophic. They can lose a lung, they can lose a whole lobe of the liver. It can take several years to get a diagnosis if the doctor is not really switched on to looking for hydatids, the patient can get progressively more unwell. "
And it doesn't stop there. The prevalence of wild dogs seems to be growing and the exposure of bushwalkers to attack and infection by hydatid that way via bites is also a real one: 7.30 Report - 16/04/2002: Wild dogs eat graziers out of business
Tom McLoughlin, ecology action sydney
[Extract of Crikey ezine 14th May 2007 here:]
Kangaroos, methane, etc:
Tim Thomas writes: Geoff Russell's comments contained several errors (Friday, comments). Kangaroos are more efficient at producing meat than sheep. True, kangaroos are not ruminants, but nevertheless efficiently ferment cellulose in their foregut. Some but, not all kangaroo species, are less efficient than sheep in processing dry feed, but make up for this by having a much lower basal metabolic rate as discussed here. In addition, kangaroos have a higher muscle to body weight ratio than sheep, discussed here, and although farming kangaroos is impractical, and in my opinion undesirable, that is not the question. If (wild) kangaroo meat is available in your supermarket, as it is in mine, then eating it lowers your contribution to atmospheric greenhouse gases. Roo shooting might not be much fun but then farming is also full of tough, unpleasant work. There is nothing more boring than preparing the ground for broad acre cropping, which includes the risk of lung damage from dust as well as exposure to a variety of chemicals, among other dangers. On all counts replacing, at least partially, ruminant meat with macropod meat would be environmentally beneficial. As to the efficiency of ruminant digestion it is interesting to note that the production of methane represents a loss of about 25% of the energy present in the animal's feed.
[Friday 11th May 07 crikey ezine]Kangaroos and methane:
Animal Liberation committee member Geoff Russell writes: Andrew Dempster (yesterday, comments) asks if kangaroos produce methane, and if not, why we can't use them instead of sheep and cattle. Kangaroos don't produce methane because of some tricky digestive processes. But they aren't very efficient in producing meat. Ruminants ruminate! This enables them to extract more energy from good pasture than kangaroos which pass food through quickly and relatively inefficiently. The kangaroo digestive mechanism is better on bad pasture, they take in and process a lot of food, while sheep and cattle face a digestive bottleneck. See Knox's "Biology" (the standard University biology text) for more detail. The bottom line here is that kangaroos aren't efficient meat producers, they don't herd, they fight, they jump fences, the mob structure isn't good for farming, and no farmer wants to give up cushy evenings watching Big Brother to go out and shoot kangaroos which is a tough, back breaking and thoroughly unpleasant job. The current kangaroo industry can't get enough shooters to even meet its current quotas which produces very little meat. Read Jared Diamond's "Guns Germs and Steel". He explains in detail why so few wild animal species have been domesticated over the millenia - it isn't for lack of trying. And if you can't domesticate them, you have to hunt them. Hunting wild animals has never and can never support large populations. Again, see Diamond for more details.
Dr Peter Wood writes: In response to Andrew Dempster's question, kangaroos produce a negligible amount of methane: Kempton et al, Methane production and digestibility measurements in the grey kangaroo and sheep. Aust J Biol Sci. 1976 Jul; 29(3): pp 209-14. (Abstract here).
Postscript #1. This important public health debate goes on in the pages of crikey.com.au ezine below, with clarification here of the life cycle indirect danger of hydatid via dog vectors, but also other systems risk of wild versus agricultural meat supply:
I'm indebted to James Thomspon [extracted below] for his sledge even though he mispells my name (Comments 16th May 2007) and partly grovel now re : "Eating red [kangaroo] meat does not result in hydatid infection." I am no vet or medical man as such and it shows now half folding my tent on this one. I had forgotten the dual life cycle of the creepy parasite from all those years ago in the lecture room. This diagram here Echinococcosis - Wikipedia, the free encyclopedia, or here Echinococcus -- Encylopedic Reference of Parasitology shows the hydatid cyst in the kangaroo whether offal or meat is infectious to the 'definitive' dog stage of the life cycle, but not intermediate host like kangas or humans.The South Australian government web site also makes it clear "People cannot be infected by eating Hydatid cysts in infected offal & Humans cannot infect humans [sic]" Hydatid disease (SA) [pdf].
Even so presence of hydatid is enough for sheep carcass to be rejected from an abattoir in WA 2006 presumably for hygiene/marketing reasons ESPERANCE REGIONAL OFFICE AGMEMO and I still doubt eating one would be much fun if not dangerous directly. It would be extremely dangerous if the pet bow wow ate it with resultant hydatid eggs in the poo then into your domestic environment (garden soil, dog hair, dog licks might be a worry too). And the concern over quality control of meat on farm versus off farm (domestic v wild) is still not over: Anecdotally pet owners are cautious with "wormy" kangaroo meat: Dogz Online and EDBA Forums > Kangaroo Meat, and animal rights people still argue with some logic of other potential contaminants in off farm or wild animal situations here in NSW Parliament re chemical sprays Kangaroo Meat Contamination - 10/10/2000 - QWN.
So I stand by the more general concern agricultural controls lessen risk compared with wild animal meat. For instance in meeting the sledge we found this submission [bold added] of Tony Pople and Gordon Grigg Dept of Zoology, Qld Uni for Environment Australia, August 1999 for the federal govt Overview of background information for kangaroo management - Chapter 7
"Andrew (1988) reviewed the issue of kangaroo meat and public health, including the records of inspections between 1980 and 1987 made of carcasses by Australian Quarantine Inspection Service officers at export game meat establishments (this pre-dated the change of legislation in New South Wales in 1993). There were records for 204,052 red, eastern and western grey carcasses of which 196,104 were passed as fit for human consumption. Of the 7,948 rejected, 81% were rejected for reasons not associated with parasites or pathology, mainly poor handling, particularly inadequate refrigeration. Of the rest, only 1,452 were rejected because of a parasite, and that was for a nematode, Pelicitus roemeri, which is quite harmless, anyway, to humans, but is unsightly.... it is uncommon, but can infect the muscles of the lower leg.."
Elsewhere the authors note people often prefer to cook kangaroo rare.
We understand 3.6 m kangaroos are being 'culled' this drought year (usually 5 or 6 million per year). That's alot of dead kangaroo with no records. Nor is a study of 20 years ago, referred to in 1999 by govt, sufficiently recent for public confidence in 2007. The onus is on the industry not the other way round.
Tom McLoughlin, ecology action
James Thompson writes: Tom MacLouglin (yesterday, comments) has either misunderstood the mode of transmission of hydatids or he is deliberately attempting to mislead the public over the risk of eating kangaroo and other red meat. I agree that hydatid cysts are a potentially serious parasitic disease of humans. However, humans are at risk from the ingestion of hydatid tapeworm eggs, laid by tapeworms living in the gut of farm dogs, dingoes or foxes that had fed on cattle, sheep or kangaroos. To avoid human infection with hydatids, after handling dogs wash your hands before eating and worm your dogs regularly. Eating red meat does not result in hydatid infection. Tom should have paid more attention during his zoology degree.