Livestock Health Scotland, under the chairmanship of former NFU Scotland president Nigel Millar, has been surveying the incidence of mastitis in Scotland’s ewe flock.
The cross industry group, responding to reports that mastitis is an increasing problem in some flocks, worked with 18 volunteer flocks in 2018 to map the incidence of mastitis, identify causes of infection and test their sensitivity to treatment.
The ewe groups were profiled at the beginning of the project, then 33 mastitis milk samples were submitted post-lambing for identification and sensitivity testing.
Most flocks were upland and lambed inside.
Those that reported mastitis post-lambing ranged from an incidence of 0.3 per cent to 2.4 per cent, with the main hill flock reporting 0.15 per cent. Some respondents noted 2018 had been a low-risk season.
Cases of mastitis in gimmers made up a large proportion of samples submitted to the laboratory and mastitis levels peaked in late April and at four to five weeks post-lambing.
Treatment approaches relied on antibiotic therapy and a minority also used intra-mammary tubes or anti-inflammatory therapy.
Penicillin and streptomycin was used by several producers, although oxytetracyclines and draxxin were reported as the drug of choice by others.
On-farm, all approaches appeared to deliver a positive response with very high recovery rates.
Mr Miller says: “The good news for the sheep sector was that all except one sample were sensitive to the range of antibiotics that were sensitivity tested. One sample showed resistance to oxytetracyclines.
There were, however, four samples which showed intermediate-resistance to oxytetracyclines and one sample which was identified as intermediate-resistant to kanamycin.
“Perhaps high levels of antibiotic sensitivity are reflected in the positive rate of recovery post treatment.”