‘No one ever forgets living through a mouse plague’: the dystopia facing Australian rural communities, explained by an expert


source, Author provided

Steve Henry, CSIROImagine constantly living with mice. Every time you open a cupboard to get linen, clothes or food, mice have been or are still there. When you go to sleep they run across your bed and, in the morning, your first job is to empty traps filled with dead mice. And the stench of dead mice fill the streets.

Even the cats and dogs get sick of mice and stop chasing them.

This is the dystopian reality for many towns as, over recent months, mouse numbers in northern NSW and southern Queensland have risen to plague proportions, devastating summer crops and fodder storages. One farmer told me he’s removing 100 dead mice from his swimming pool each night.

This week, for example, truckloads of sorghum from Southern Queensland farms have been rejected from sale after mouse droppings were discovered. This means loads of grain need to be cleaned before they’re suitable for sale.

No one ever forgets living through a mouse plague.

One of the largely unquantified repercussions of mice is the social and mental health impact on farmers, their families and rural communities — places only just starting to recover from the recent, devastating drought.

I work with scientists and rural communities to reduce the impact of mice. So, with no end to the plague in sight, let’s look at the issue in more detail.

Mice outbreaks in Australia

The earliest accounts of mouse outbreaks in Australia are from the late 1800s, after the house mouse, Mus musculus, was likely introduced in the late 1700s as stowaways with the First Fleet. Similar plagues are uncommon in other countries — even though mice are found worldwide — as favourable climates lead to lots of food and shelter, which sustain high mouse populations in Australia.

Outbreaks like we’re seeing now tend to follow a run of dry years. The house mouse is very well adapted to live in Australian conditions, and they can survive through protracted dry periods and thrive when there’s lots of food and moisture. While often not conspicuous, they’re present in most environments — all the time.

As climatic conditions become favourable for crop production, they’re also favourable for mouse breeding. And mice reproduce alarmingly fast.

They start breeding at six-weeks old and give birth to a litter of six to ten pups every 19 to 21 days after that. After giving birth to one litter, females can immediately fall pregnant with the next litter, meaning there’s no break in the production of offspring.

In good seasons, when the rate of survival is high, the rate of population increase is dramatic. A single pair of mice can give rise to 500 mice in a breeding season. This year, the breeding season has lasted through summer and into autumn, as the weather has been milder with lots of rain.

Desperate times, desperate measures

Mouse outbreaks or plagues occur across the cropping zone — the extensive area where crops are grown in Australia — approximately every five years. However major outbreaks like the one we’re experiencing today are less frequent.

In some towns across the cropping zone, the smell of dead and decomposing mice is becoming a significant problem in shops, rubbish bins and under buildings and homes, where mice that have been baited have gone to die.

And the outbreak is growing. I’m getting reports from farmers of high mouse numbers from other parts of the cropping zone, through southern NSW, Victoria and South Australia.

A haystack with a blue tarp over it
1,600 bales of hay, completely decimated by mice.
Adam Macrae, Author provided

Mice can cause damage during all stages of crop growth, and they don’t limit themselves to cereals. Farmers have reported significant damage in canola, lentils and other pulse crops. Likewise, mice removing freshly sown seed, browsing shoots and feeding on developing heads and seed pods all reduce crop yield.

Mice also cause significant damage to on-farm storages of grain and fodder. Contamination of grain with mouse faeces can lead to grain distributors and export markets rejecting produce (such as with sorghum in Southern Queensland).




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This year has been so bad, farmers say they’re giving up on efforts to control mice with bait, and instead ploughing their summer crops back into the ground. Other desperate measures include burying entire haystacks to protect them from total decimation by mice.

The cotton industry, rarely impacted by mice, has even sought an emergency permit to allow control of mice in cotton crops using zinc phosphide baits, the only approved chemical control measure for mice in broad-scale agriculture in Australia.

So how does this horror end?

The drivers for the end of a mouse outbreak are not well understood. It’s thought a combination of high numbers, food running short and disease leads to mice turning on each other, eating sick and weak animals and offspring, resulting in a dramatic crash in the population. Farmers, in previous outbreaks, have reported mice disappearing almost overnight.

CSIRO is developing strategies to reduce the impact of mice in agriculture.
Sharon Watt, Author provided

CSIRO, with the support of the Grains Research and Development Corporation, is working on developing a range of new ways to reduce the impact of mice in crop production systems. Key focuses include monitoring populations to make predictions about future outbreaks and developing of better predictive models.

We’re also investigating how current cropping practices influence mouse behaviour and their population dynamics. This will help us assess potential new control strategies, develop more effective baiting procedures, and consider the potential of future genetic control technologies.

Still, the introduced house mouse will be an ongoing problem in Australian farms and rural communities for years to come. We must urgently find ways to reduce the economic and social impact of mice, not only for the sustainable production of crops, but also for the mental well-being of rural communities.




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The Conversation


Steve Henry, Research Officer, CSIRO

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Explainer: what is leptospirosis and how can it harm us and our pets?



When a game of fetch can harm: leptospirosis can be transmitted to dogs (and humans) from stagnant water contaminated with rat urine.
from www.shutterstock.com

Christine Griebsch, University of Sydney and Jacqueline Norris, University of Sydney

Recently reported cases of the often fatal bacterial infection leptospirosis in dogs in Sydney have raised the issue of animal diseases that also affect humans.

This zoonotic disease is spread by rats and other rodents. However, this latest cluster in dogs has not been accompanied by human cases in the Sydney area so far; dog cases aren’t always accompanied by human cases nearby.

So what is leptospirosis? And what can we do to protect ourselves and our pets from this potentially fatal disease?




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There have been at least six confirmed cases of canine leptospirosis so far in Sydney’s inner west and city in 2019, with three in May and June. Five of the six dogs died.

So far, these cases have been confined to one part of Sydney but we don’t know the source of the infection. Some people have speculated that recent building work may have dispersed rats and spread contaminated water through flooding.

How is it spread?

Leptospirosis is caused by Leptospira bacteria that rodents and other animals can transmit to animals and humans.

Dogs can become infected by direct contact (for instance, from a rat bite or from eating rats) or via indirect contact (for instance, by drinking urine-contaminated water).

Clinical signs might not show up in dogs for about seven days. Early signs can be vague — fever, lethargy, anorexia (loss of appetite), vomiting and diarrhoea.

Dogs can also shed bacteria in their urine without being clinically sick (“silent shedders”). This and contact with sick dogs poses a potential risk to other dogs and people coming in contact with their urine.




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Severely affected dogs can develop acute kidney failure, liver injury and jaundice (yellow discoloration of the skin), uveitis (inflammation of the eyes), bleeding and in severe cases bleeding into the lungs leading to breathing difficulties. These clinical signs are the result of damage to the blood vessels (vasculitis) and resulting damage to organ blood supply.

Veterinarians can confirm the diagnosis after taking blood and urine samples. In suspicious cases, treatment with antibiotics needs to start quickly, even before the disease is confirmed by lab tests, to minimise organ damage. Severely ill dogs will require intensive care, ideally in an intensive care unit.

How do humans catch it?

As well as being exposed to bacteria from their infected pets’ urine, humans can become infected by rodents themselves. This can be directly (from a rat bite) or if a wound is exposed to soil or water contaminated with rat urine. Eating contaminated food or drinking contaminated water can also be responsible for transmitting the bacteria.

Humans might not have symptoms for two to 25 days. But in 90% of human cases, these are mild and mimic influenza.




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Less commonly, more severe disease can develop, which can be similar to what we see in dogs, and is known as Weil’s disease.

According to NSW Health, these more severe symptoms include kidney failure, jaundice (yellow colouration of the skin and eye balls which indicates liver disease), and haemorrhage into skin and mucous membranes. Meningitis (inflammation of the lining of the brain) and bleeding in the lungs can also occur. Most people who develop severe disease need to go to hospital, and severe leptospirosis can sometimes be fatal.

Leptospirosis is a notifiable disease in humans which means that laboratories have to notify cases of leptospirosis to the local public health unit. This year, 51 cases have been reported so far in Australia, but none of these have been linked to the current outbreak in dogs.

How do we prevent it?

We can prevent leptospirosis by limiting contact we and our pets have to sources of infection, and by vaccinating our dogs.

Make sure dogs don’t swim in and drink from stagnant water like ponds, lakes or puddles.

Wash your hands after contact with stagnant water, soil, urine from rodents, dogs or cats or simply after any contact with pets, especially before eating.

Similarly, avoid contact with rodents, and make sure you correctly dispose of garbage to reduce the chance of attracting rats.




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Until now, leptospirosis has rarely been reported in Sydney. So, dogs are not routinely vaccinated. But we currently advise vaccination for all dogs in the inner west and city area.

The vaccine available in Australia protects against one serovar (type of the bacterium), and we do not know if this is the only type causing recent problems. Vaccines against multiple serovars are available overseas.

To learn more about the current cluster, we have started a research project. This will investigate the geographical distribution of the recent outbreak and the serovars of the bacteria involved. We are also collaborating with Sydney veterinarians who, with pet owners’ consent, are taking blood and urine samples from dogs before they get vaccinated against leptospirosis.

Hopefully then, we can better understand this latest cluster and how we can protect animal, and ultimately, human health in the future.The Conversation

Christine Griebsch, Specialist and Senior Lecturer in Small Animal Medicine, University Veterinary Teaching Hospital Sydney, Sydney School of Veterinary Science, University of Sydney and Jacqueline Norris, Professor of Veterinary Microbiology and Infectious Diseases, Sydney School of Veterinary Science, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

MICKEY MOUSE IS A SATANIC AGENT


EDITORIAL NOTE: This post includes satire and although the actual base story is true, my comments should be seen as satire and do not accurately portray my viewpoints.

At last, that great agent of Satan, Mickey Mouse, has been revealed for all to see. We have all long expected that such beings as Mickey Mouse, Donald Duck and Elma Fudd are secret agents working for Satan.

How better off would we be if these characters had been eliminated years ago? Surely legislation must be passed to outlaw these characters, with shoot on sight allowances being made for gun owners, especially in the United States. If all gun owners were allowed onto the streets to take out any Mickey Mouses, Donald Ducks, Elma Fudds and all other such characters, how much better would we all be?

Oh to be rid of Ronald McDonald all of our dieting problems would be finished and one of Satan’s great weapons against mankind would come to an end! No more gherkins to haunt us as we eat. No more fear of our burgers being swept off by a hamburgler! No more large Grimace-like creatures to scare children!

All thanks to Sheikh Mohamed al-Munajid the former Saudi diplomat to the United States for telling us that household mice and their animated counterparts must be rubbed out! Mickey Mouse is one of Satan’s soldiers according to the Sheikh.

If only the United Nations could form a committee to oversee the elimination of these demon soldiers!

See more about this at:

http://www.worthynews.com/news/foxnews-com-printer_friendly_story-0,3566,427061,00-html/