Sheep freeze branding developer releases ‘positive’ research report

Terry Sim April 28, 2021

Sheep freeze branding developer Dr John Steinfort.

SHEEP freeze branding developer John Steinfort is happy with the conclusions in a long-awaited final research report from University of Melbourne researchers into his  surgical mulesing alternative …

Because they match what he and other farmers seeking an accepted option to mulesing have observed on farms.

“It puts aspects of it in a positive light which is where it needs to be, because that’s what we see every day,” he said.

“It is proving the process for what it is; the trial is what it is.”

The UniMelb researchers have concluded they were unable to detect major behavioural differences between freeze branding and the mulesing treatments in the trial when both were accompanied by pain relief.

However, some differences were observed between all breech modification treatments (freeze branding with meloxicam (FB), tail docking/castration with mulesing and meloxicam (MM), and tail docking/castration with mulesing plus Tri-Solfen (MS), and lamb marking (T/C) only, with pain relief provided for all treatments, in the first two days post procedures, the report said.

“Over the longer term, the slightly better weight gain and the described differences in wound healing, suggest that the freeze branding application may provide these animal welfare benefits over surgical mulesing.”

The research compared 120 Merino ewe and wether lambs broken into four groups: 1. The control group – Tail-docking (hot iron) (+ ring castration of male lambs) with meloxicam injection (T/C); 2. As controls + freeze branding (FB); 3. As controls + surgical mulesing (MM), and; 4. Tail-docking (+ castration of male lambs) + surgical mulesing with Tri-Solfen application (MS). There were 30 lambs per treatment.

The research data aggregates also indicated that on day one after treatment, freeze branded lambs recorded the highest measure of pain avoidance behaviour of all treatments (0.67) — twice the measure of lambs tail docked/castrated with meloxicam and/or mulesed with Tri-Solfen, and five times the measure of lambs mulesed with meloxicam. Lambs freeze branded with meloxicam recorded abnormal standing behaviour (at 6.8) more than twice that of lambs tail docked and castrated with meloxicam (3.23), but were similar in this measure to lambs mulesed with meloxicam (6.83) and to those mulesed with Tri-Solfen (6.73).

The report result’s also show that the time for lambs to mother up was longer for those freeze branded versus those mulesed with Tri-Solfen. The final report also does not comment on any effect on the trial results of the group of lambs that did not get pain relief (meloxicam) for castration — the male lambs in the mulesed-Tri Solfen group — which might have had an impact on the lambs’ behaviour and weight gain, and any comparisons with lambs in other groups. There is also only a small difference between the total weight gain between lambs that were freeze branded (6.64) and those that were mulesed with meloxicam (6.49) or mulesed with Tri-Solfen (5.84) — the group’s whose male lambs had no pain relief for castration.

The final report’s stated conclusions also contrast with the preliminary conclusion of lead researcher Dr Ellen Jongman late last year that freeze branding (with meloxicam pain relief) appeared to be more painful than tail docking and castration alone, and similar to mulesing (with meloxicam), on the day of application.

“So it’s not a painless procedure and it may even be similar to mulesing on the day of application,” Dr Jongman said after releasing her preliminary data to the 10th National Primary Industries Animal Welfare RD&E Forum in December last year.

Although Dr Jongman assured Sheep Central in March that further analysis of her preliminary data wouldn’t change the preliminary results or her research conclusions, Dr Steinfort today said the final report did not repeat her initial pain assessment of freeze branding with meloxicam “because the numbers hadn’t been fully assessed.”

“She rushed that to get that to that animal welfare forum and she gave us a paragraph that she said she would do and we agreed to that and I went from there.”

Dr Steinfort said the preliminary conclusion that ‘freeze branding (with meloxicam pain relief) appeared to be more painful than tail docking and castration alone, and similar to mulesing (with meloxicam), on the day of application’ no longer held true.

“No, the final report is the final report.

“What she put up there was inappropriate at the time, because she didn’t have the full details and going through the full details she found out further, which changed all that,” he said.

“I was so upset with what you wrote because I knew it wasn’t true anyway.”

Dr Steinfort said Sheep Central’s initial reporting of Dr Jongman’s preliminary results did not give any context, as in it didn’t state that tail docking and castration were also painful processes.

“They all have some pain or discomfort associated with them.”

Dr Steinfort said the trial was not designed to assess the level of initial pain associated with mulesing shears, of tail docking or of the breeze branding application. However, he believes the trial has provided an overview of the pain associated with freeze branding and the other  procedures “with the limited numbers and the nuances that are there … we can only accept the paper for what it is.”

“We will keep going forward, as I have always said, I would like to do a really objective trial, an objective trial out in the field, not in containment yards.

“Out in the field where they are mothering up, where they are grazing with mobility and proximity meters is the next trial we would do and that will show a very positive light yet again.”

Final report release was delayed

Despite attaching the final report to the Australian Wool Exchange on April 6 with his submission to the latest National Wool Declaration review, Dr Steinfort delayed the report’s public release until today to allow the preparation of accompanying review report by Hamilton veterinarian consultant Graham Lean, and a media release proclaiming ‘Melbourne University trial demonstrates positive outcomes from freeze branding.’

Dr Steinfort said his recent illness had delayed the release of the research report, but he said it also needed to have a review and context report — commissioned with Dr Lean — associated with it, “for everybody else in the industry to understand the differences and the nuances and how to interpret the trial.”

“I got that through an independent veterinarian as well, which is good.

“I commissioned him, yes.”

Dr Lean’s review of the report listed the positive outcomes associated with freeze branding such as better weight gains and improved lamb behaviour, concluding that freeze branding delivers better lamb welfare outcomes.

“The incidence of abnormal behaviour was low during the trial. On Day 3 after treatment there were no significant differences in behaviour across the different treatments.

Abnormal behaviour is usually taken as the best standard to judge animal welfare. Unfortunately, there were some confounding factors and limitations to the study,” Dr Lean said.

“Firstly, low trial lamb numbers meant some of the behavioural differences were not statistically significant, so a number of behaviours were aggregated to strengthen statistical power.

“Therefore, there may be some limitations to the interpretation of these results,” he said.

“Lameness was found to be present in the trial sheep flock during the trial.

“This is likely to have been a confounding factor for assessing behavioural changes associated with the various treatments.”

In listing some of the trial’s limitations, Dr Lean said the limited numbers of lambs in each treatment group and the presence of virulent footrot in the sheep “could have made behaviour difficult to interpret and differentiate properly differences between the treatments.”

However, Dr Lean said the trial showed that freeze branding of sheep with pain relief had significantly better weight gain than those mulesed with pain relief, that flystrike risk is eliminated because of the lack of an open wound and lamb behaviour was similar in mulesed and freeze branded sheep treated with pain relief.

Dr Steinfort also released a testimonial New South Wales wool growers Leo and Judy Blanch at ‘Westvale’, Wollun, who said that from their positive first-hand experience of freeze branding they firmly believed the process showed a marked improvement in animal welfare outcomes when compared to traditional mulesing. They would like to see the process identified in a separate category on the National Wool Declaration, “so as not to jeopardize those people who have bred sheep for no (breech) modification.”

The footrot question

Dr Jongman’s final report only referred to lameness in some of the trial sheep, rather than identifying virulent footrot; however, Dr Steinfort excused this.

“That’s the thing, not everything is going to be mentioned in that report until it is fully published, then further refinement between the two mulesing groups will be brought into focus,” Dr Steinfort said.

He said the virulent footrot in the trial sheep undermined the data from all the trial groups putting “variances and nuances in there.”

When asked if the trial demonstrated that meloxicam handled the initial pain associated with freeze branding application, Dr Steinfort said: “I think the trial really demonstrates the benefits of pain relief for all lamb marking processes.”

“When we’ve used meloxicam at lamb marking with sheep freeze branding you get less wether animals going down and showing signs of pain.”

“What I say is that the animal feels a stimulus when the liquid nitrogen is being applied – it feels a stimulus to its skin.

“But once it jumps out of the cradle it just runs off back to hunting out its mum and away it goes.”

Now to the NWD Review…

On whether wool industry stakeholders should now be able to make further submissions toe the Australian Wool Exchange’s National Wool Declaration review, Dr Steinfort said AWEX board members had a good diverse skillset and would be able to make their assessment of the report “for what it is.”

“Basically, it (freeze branding) is not mulesing and therefore it should be in a non-mulesing category of some sort and then industry should accept that,” he said.

“And the animal welfare groups if they want to have a meeting, that’s fine, let’s sit down and talk about it – why don’t they actually come out and have a look, that’s even better.

“Industry should grasp onto this, they’ve got an opportunity now and it is probably the last opportunity they will have for an alternative (to mulesing) in the industry itself, for sure.”

Dr Jongman was asked several questions about her final report and its interpretation, but had not responded before this article was published.

Click here to read the final sheep freeze branding research report.


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  1. Don Mudford, April 30, 2021

    I really can’t understand the resistance to breeding a sheep that does not require mulesing and that is highly blowfly resistant, produces better quality wool, weans more lambs, encourages young people into the Merino industry, earns more $s per hectare with more wool and more lambs, that are quicker to fatten. Stop trying to sell the industry chemicals creating issues for shearers trying to shear tough sheep and driving more people out of our industry.

  2. Doug Wright, April 29, 2021

    Freeze branding is being talked about as the last alternative to mulesing in the industry. The reality is that you still have a sheep that is still prone to body strike, with the need to use jetting chemical and is of lower natural fertility. The long-term answer has been around for some years — the genetic solution — making all forms of breech modification unnecessary.
    In the meantime, the National Wool Declaration needs to inform the trade of the history of the sheep and not attempt to hide breech modification as non-mulesed.
    Further, in relation to freeze branding, the costs and logistics of use need to be put out for comment.
    I am so pleased that the genetic solution is available and is being used. In 2025, wool producers that are on this method will be well-placed when the major retail brands have indicated that they will only be buying wool from non-mulesed and non-breech modified sheep.

  3. Paul Favaloro, April 29, 2021

    University of Melbourne has called this what it is: breech modification. The conclusion says it all.
    Quote: “In the present study we were unable to detect major behavioural differences between freeze branding and the mulesing treatments.”

  4. Jim Gordon, April 28, 2021

    A very simple solution, AWEX board: tell the truth. Then we will start getting respect from the retailers, brands and exporters. Three separate boxes on the National Wool Declaration: mulesed, freeze branded and non-mulesed or no breech modifications. There can be a space in those boxes for pain relief, if that is used. Another box for lamb marking with or without PR.
    Very few growers have a problem with freeze branding. The problem is not telling the truth. Stop trying to get into bed with the non-mulesed wool on the NWD.

  5. John Symons, April 28, 2021

    It’s interesting that the trial sheep had virulent footrot. I bet that will create more discomfort over their lifetime than the discomfort of breech modification. However, if I don’t mules I can tick that box on my National Wool Declaration and I am a fantastic manager of my flock. But I could have lost 15 percent with fly strike, footrot, lice and worm infestation etc. But that doesn’t rate a mention.

    • Andrew Michael, April 30, 2021

      Signing the wool declaration for non-mulesed certainly doesn’t mean that you tick the box as a great manager for all aspects of animal well-being within your sheep business. The debate around the effects of mulesed versus non-mulesed across the whole industry has been reviewed, researched, legislated, trialled, debated and flogged to death for years with very little or no progress.

    • Jim Gordon, April 28, 2021

      John Symonds, it doesn’t matter if you lose 50 percent of your flock to flies, footrot, lice and worms. It doesn’t rate a mention because it only affects you. The welfare groups can’t come onto your farm. The mulesing issue affects the whole industry and if we don’t fix it, it could bring the industry down. We only need half the Merino sheep not mulesed. That wool can supply the non-mulesed market and the mulesed wool can supply the market that doesn’t care. A Chinese bus driver or the armed forces don’t care if a sheep was mulesed or not.

      • Edward H Wymer, May 1, 2021

        Jim is spot on, except he underestimates it, most people wouldn’t have a clue what mulesing was and wouldn’t care. The whole debate has become tedious.

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