Tag retention/Ear Infections

We are having some serious tag retention issues in some of the sheep tagged. From a batch of 500 hoggs tagged last backend we have had to replace 140 at clipping time due to the ears going septic. We have sent the samples of the ears to Greycrook to find out the cause which is identified as Staphylococcus aureus in 5/7 samples submitted. S. Aureus is an opportunistic pathogen which can infect the skin in case of trauma, such trauma inflicted by ear-tagging. We have also tagged about a 1000 lambs at lambing and marking and a lot of these are appearing to go the same way (numbers will follow). However for some reason its the inbye breeds that seem to be affected with this. Is there a case of welfare in this? I can supply a copy of the report if required.

Tag Retention

Hi I've just joined the pilot and found this tread particularly interesting. I have been using RD 2000 with a high visibility flag for a number of years now and retention was excellent, that is until 2008 when we did note some losses. However losses in 2009 were much worse.

Since double tagging started we have used a standard one piece tag as the secondary tag. In 2009 we were slightly later than usual in tagging and a high percentage of the lambs developed infections in the RD2000 ear only, there were no infections apparent in the ear with the one piece even in the same lamb. Losses of the RD 2000 were much higher in 2009 however not all lost tags was attributed to the ear infection as we keep finding male and female parts of tags in the grass that appear to have come apart. I was checking over some hoggs recently and found a number of tags about to come apart and these were easily pushed back together between your fingers. This looks like a design fault to me.

With regard to the infection, it looked to me almost like an Orf scab. Just a theory but I attributed this problem to two factors:

1) tagging in warmer damper weather plus Midges causing lambs to sctarch along fences before wounds healed.
2) RD 2000 has a pretty hefty pin and tends to be more mobile in the ear, particularly with the high visibility flag in place and perhaps not allowing the the wound to heal quickly enough.

So its back to small and simple tags this year,doing away with the larger high vis type and will hopefully be able to afford a reader for management purposes. As mentioned elsewhere on the forum, as the flock is small I'm considering EID for all the stock- helps to justify investment in a reader.

Tag Retention

Thanks for a most useful and interesting post.
We have a wee flyer coming out soon with some "golden rules for tagging" - will stick it in here as soon as I get it.
Admin - H


It appears that the infection in the ears becomes obvious several months down the line. I would agree with your statement regarding tagging on wet days, however my current crop of lambs were tagged at birth in a dry environment and without holding lambs in for weeks, this would be unpractical. It also appears that there is no greater numbers of EID tags to non-EID tags. I will send a copy of the report to support.

Thanks for the input

Thanks for the valuable input.
Yet again you have given us a lot to think about.

Investigation is being planned

This is certainly a big cause for concern as it impacts on both tag retention and animal welfare. The pilot is planning an investigation into this to begin shortly and we would certainly be very interested in reading your report and hearing from anyone else experiencing similar problems.

I presume that the tags you are using pierce the ear rather than the applicator and that there is no difference in infection rate between the EID and non-EID tags, but would be interested to hear if that is not the case.

For anybody yet to tag their sheep the guidelines below give some advice on ear tagging which may reduce the risk of ear infections.

DEFRA advice
SAC advice (below "top tagging tips" section)

The advice not to tag on a wet day is probably the most relevant.

Wikipedia article on Staphylococcus aureus

Tag placement

If the infections are mostly occuring shortly after the tags have been inserted it would suggest that the infection is being introduced whilst the wound is still fresh. If this is the case then it may be worth using an antiseptic lubricant, if you are not using one already.

If the infections are happening later it would suggest that the wound is not healing properly or is being aggravated, possibly from scratching or getting the tag caught in things like wire netting, feeders etc.
It may be another species, and metal rather than plastic tags, but the article "Eartag induced Staphylococcus aureus infection in mice" reports that the positioning of eartags is a very important factor. The article states that if the eartags were placed in a location which the mice found uncomfortable they would scratch and pull at the tags continuously traumatising the site leaving the route open to infection. Its not hard to imagine lambs behaving in a similar fashion if they found the tags to be uncomfortable.

Disclaimer: I am not a vet.