By Siouxsie Wiles 29/02/2016

In the spirit of openness and transparency, I want to share what 42 animals that were involved in my 2014 research efforts experienced.

I recently blogged about Paul Henry’s interview with NZ Anti-Vivisection Society (NZAVS) executive director Stephen Mason, in which Paul Henry repeatedly referred to the 300 animals a day tortured to death in the name of science. I’m paraphrasing, but you can watch the interview for yourself here. Stephen Mason was talking about the 2014 figures for the animals used for research, teaching and testing in New Zealand, just released by the Ministry for Primary Industries. He condemned the secrecy and lack of openness by publicly funded New Zealand institutions using animals. I agree with him. I wish that we would adopt a similar concordat to the UK in which almost 100 institutions, charities and companies have committed to help the public understand more about animal research. 

I contacted Paul Henry’s producers and offered to talk about the animal research I carried out in 2014 but, after a chat with one of his team, I didn’t hear from them again. But who need’s The Paul Henry Show when we have SciBlogs! So here’s one of the things the Bioluminescent Superbugs Lab were researching in 2014.

The Problem.

In 2013 I was approached by an orthopaedic surgeon, Simon Young, whose aim is to prevent any of his patients developing an infection from their surgery. At the moment, patients who are having knee replacement surgery are given intravenous antibiotics at the beginning of surgery to try to kill off any bacteria that might accidentally contaminate the surgical site during the surgery. Despite the best efforts of their surgeons, about 2-3% of knee surgery patients develop an infection, sometimes months to years after their surgery. Some of these patients will require the replacement knee to be removed and replaced again. Sometimes the infection can never be completely eradicated and patients can end up in severe pain, some even losing the use of their limb.

Simon wanted to test out a different way of delivering the antibiotics. It’s called intraosseous delivery. The idea is that the surgeons apply a tornique to the limb being operated on, and then inject a large dose of antibiotics directly into the bone. This puts the antibiotics exactly where they are needed and means they can get higher doses than if the antibiotics are delivered to the knee via the blood stream and the rest of the body. The idea could be trialled on his patients but because it can take months to years for patients to develop an infection, and only a small number of them will get an infection in the first place, Simon wanted to know if it was worth going ahead with such a study. And that’s where the Bioluminescent Superbugs Lab came in!

Our experiments.

We got some money from the New Zealand Orthopaedic Association, and permission from our local animal ethics committee, to try out Simon’s idea on mice, performing knee surgery and then deliberately infecting the surgery site with a bacterium that can often be found causing infections in people after surgery. We’d be delivering a very unrealistic dose of bacteria, but testing different ways of delivering the antibiotics to see if they could reduce the amount of bacteria. If this worked, the technique would be likely to kill the small number of bacteria that manage to infect the surgical site of some patients and go on to cause an infection.

Once we had our scientific question, it was my job to apply the 3R’s (replacement, refinement and reduction) – the ethical framework that governs the use of animals in research. As we dont’t have a replacement to mice in this case, I had to think about how to refine the experiments to cause the least suffering, and how to use the minimum number of animals. Being the Bioluminescent Superbugs Lab, the first technique we decided to use was biophotonic imaging: the visualisation and measurement of light from within living animals. Using biophotonic imaging, we could infect the animals with a glowing strain of the bacterium Staphylococcus aureus and then track whether the bacteria were dead or alive for a few days after surgery and delivery of the antibiotics. We could get data on the dynamics of how the treatments were working without having to use large groups of animals and euthanizing some of them each day after surgery to grow any living bacteria. The technique would also make the experiments more humane, as it would give us a head’s up if the bacteria were moving into the bloodstream to cause a more serious infection, without us having to wait for the animals to show any physical symptoms.

Once we’d decided we were going to use glowing S. aureus, we then had to settle on a dose of bacteria that would be bright enough for us to detect with our biophotonic imaging machine. To do this we didn’t use animals at all, but laid slices of ham over different amounts of bacteria to see which doses we could still detect. Dose sorted, we moved on to the experimental design. It’s important for experiments like these to carry out the surgeries on different days, using different cohorts of mice and different batches of bacteria, just in case something behaves oddly. We settled on 6 treatments (5 different antibiotic therapies and a no-antibiotic control) and chose to use a randomised block design so that on any given day one or two mice were randomly allocated to each of the 6 treatments. This was repeated on 6 different days to give us surgeries, treatments and infections that had been independently carried out at least 6 times, using a total of 42 mice. An alternative experimental design would be to use groups of 5-6 animals for each treatment and perform the experiments on 2-3 different days, using 60-108 mice.

Having settled on an experimental design, we then met with the animal welfare officer to go through our surgery plan (you can see photos of each of the steps of the surgery on FigShare here) and discuss the best way to relieve any pain the mice might experience afterwards. We settled on giving the mice a subcutaneous injection of carprofen each day and putting paracetamol in their drinking water. The surgery was done under anaesthesia by an orthopaedic surgeon and then the animals cared for by my team. Each day the mice were visually checked to see if they were looking bright eyed and behaving in their usual inquisitive way. They were also weighed to check they were eating properly. Two of the mice started losing weight so they were euthanised, but the rest all recovered really well from their surgery, running around and climbing up and down inside their cages* like they normally would. Each day the mice were also given a light dose of gas anaesthesia and imaged to visualise any glowing S. aureus. Four days after surgery the animals were euthanised and the knee dissected out and put onto agar to grow up any remaining S. aureus which could then be counted.

Our findings.

You can see some of the results of our experiment below. Click on the figure to see it in better resolution. Three groups of animals are shown, the first 7 were not treated with any antibiotic. The top line is the mice imaged 24 hours after surgery and the bottom line is 96 hours after surgery. The blue/red splodges are the S. aureus glowing within the mice.


In a nutshell we found that intraosseous administration of antibiotics was more effective at reducing the number of S. aureus than the same dose of antibiotic delivered intravenously – you can see there are less glowing splodges on the those animals than any of the others. All in all a success, and good evidence from 42 mice that studies should be done in humans. Our findings were published in the journal Clinical Orthopaedics and Related Research (1) and described in an accompanying editorial as “elegant” (2). Our paper is open access so you are welcome to go and read it for yourself. A word of warning though, the target audience is surgeons so it’s a little dry….


  1. Young SW, Roberts T, Johnson S, Dalton J, Coleman B, Wiles S (2015). Regional intraosseous delivery of prophylactic antibiotics effective in a murine model of total knee arthroplasty. Clinical Orthopaedics and Related Research. 473(11):3573-84. doi: 10.1007/s11999-015-4464-x.
  2. Zalavras  CG (2015). CORR Insights: Regional Intraosseous Administration of Prophylactic Antibiotics is More Effective Than Systemic Administration in a Mouse Model of TKA. Clinical Orthopaedics and Related Research. 473(11):3585–87. Doi: 10.1007/s11999-015-4521-5

*We call them cages, but that makes people think of wire bars. We use what are known as individually ventilated cages (IVCs) which are self contained houses made of clear plastic. Inside we provide corn cob, bedding material and usually either little houses of empty toilet rolls for the animals to nest inside of or play with, as well as free access to food and water.


0 Responses to “Are 300 animals a day really tortured for scientific research in New Zealand? Part II”

  • I do not get funding to research on animals and how I perceive performing needless surgery on mice and an animal’s life spent in a small cage is different .
    I believe you have cognitive bias.

    The way antibiotics travel through the human body( and the antibiotic human efficacy) is different from mice so there is no need for the experiment.
    .IV antibiotics have already been found to be more effective.
    There is truly nothing “human” in the research on animals and no human being would think it was Ok to put a human being in an IVC( cage) for the duration of life.

    • Thanks for commenting Anabel. As I explained in the post, giving IV antibiotics is not working for all patients – some patients even have nasty side effects to the large concentrations that are needed to deliver the right amount to the small part of the body it is needed most. That’s why the surgeons wanted to try this new method, of delivering large doses of antibiotic, only where they are needed. In this respect, the way we did the experiments is comparable between mice and humans.

      I understand that you find it difficult to imagine how we can keep mice in a “small cage” and no amount of me telling you they are well cared for will change that, and it is your right to hold that belief. In this respect, I think we can both admit to having cognitive bias. Can I ask if you also don’t believe children should have pet mice and hamsters?

  • The reason antibiotics are not working for some people is due to the continued misuse of antibiotics and development of resistance in some.
    If the IV antibiotics (which are are only for serious infections)are injected into the blood it goes through the whole system and does not stay in one “small part of the body”.

    In the experiment on mice it served no purpose as you still cannot predict how each different patient will respond to which antibiotic at varying doses . Mice are not human beings.

    I do not have cognitive bias as my funding does not come from animal experimentation.
    I understand that you would find what you do to animals is ok to be done on yourself?

    Answering your question, no I don’t think children should have mice and hamsters in cages performing unnecessary operations on them.

    • The fact the antibiotics go to the whole body and not just the site they are needed is precisely the point. It means it can be difficult to get the high concentrations where they are needed. That’s why the surgeons wanted to try this alternative way of delivering them. In the experiment in the mice, the IV antibiotics served as a control – a crucial thing needed to answer our question as to whether the new method was better.

      My question was not whether children should be performing unnecessary experiments on their pets, only whether you agreed with children keeping pets in cages.

  • Anabel, perhaps you could explain what your background/are of expertise is, in case you yourself are suffering from cognitive bias?

  • You did not answer my question on whether you would agree that it was humane if you were personally subjected to the experiments ,a caged life and euthanasia 4 days after(aka what is done to lab animals) .

    It seems that science, following venture capital funding, somehow we have switched the meaning of barbarian for the the word “humane”.

    The mice cannot act as, or be seen as, be a human control group.

    Before you started the experiment it was already widely known /concluded “A comparison of intravenous (IV), intramuscular (IM), and intraosseous (IO) routes of administration concluded that the intraosseous route is demonstrably superior to intramuscular and comparable to intravenous administration (in delivering drugs.”
    That is why it was needless.

  • Hi Anabel,

    “That is why it was needless.”

    That would ask that medics and scientists assume a new approach would ‘just work’ because the basic principle of the idea sounds promising.

    On the face of it, it certainly looks a promising idea, but plenty of promising ideas don’t work as well as might be hoped.

    The point of the testing is to find out if the promising idea is good as it might seem.

    • The research idea was that surgeon Simon wanted to prevent the infection in 2% of his patients by treating an infection aggressively with IO ( before it starts).

      This type of thinking that he demonstrates ignores the fact that some surgeries are not successful,patients with immune problems or underlying un-diagnosed conditions do not heal well,super-bugs,age, overuse, and there are complications (such as human error).Maybe Simon has a 2% surgical error rate (which is still low rate for surgical errors in NZ for performing knee surgery).
      These poor mice were only allowed 4 days life which is not related to preventing infection of the 2% who have knee infections months/years after surgery.

      The experiment did not provide us with any knowledge we didn’t have already.

      It is wrong thinking to think mice make for a “control group for human beings .
      IO use in human knee surgery infections is no more “promising” on human beings now than it was before the IO testing on mice.

      • I’m sorry for my sloppy language. When I said the IV mice were a control, I meant for the IO mice.

  • Anabel, you demand that Siouxsie answer your questions, however, you don’t seem to be willing to answer questions asked of you here – that seems a little unfair.
    I would be interested in knowing what sort of life you think mice deserve. It doesn’t seem like much of a life in the wild with the various predators etc.
    Also I would be interested in what you view would be on dealing with large populations of mice such as this?

    I would also be interested in what background you have to be able to make statements such as “IO use in human knee surgery infections is no more “promising” on human beings now than it was before the IO testing on mice.” ?

  • Hi Michael
    If you read the comments again you will find I did answer the questions Siouxsie Wiles asked me, though the answer was not what you wanted to hear .. She is perfectly capable of further inquiries if my answers were not good enough for her.
    How do you want to live your life ? In a cage, cut up, euthanized, Happy to live a short life like this just as an experimental animal in a venture capital driven research industry?It is not “humane” , my point was the money$ counters conditioned taught ideas about animals have just convinced you it is that it is .
    Would you like an example of a wrong idea that has widespread unquestioning belief? How about when people believed the earth was flat and that they would fall off it. How about in the middle east where they believe it is “justice” to stone people to death for homosexuality . Just because an idea or act is widely accepted it does not make it right.

    @Siouxsie I enjoyed reading Professor Tim Stokes article on COI
    ” Bias weakens the evidence base for health care decisions. We may think we are doing ” good” but may in fact be doing more harm than good”
    And ( speaking of bias) looking a COI he can address how the funders such as ACC & DHB ( that make only denial/cost cutting treatment decisions) set up a COI and usurp the dr patient relationships which use to be primary not secondary.