A thousand sheep have been vaccinated against anthrax and a Victorian farm is in quarantine after two sheep were killed by the deadly bacterial infection.
Agriculture Victoria said it had quarantined a Swan Hill dryland cropping and sheep property after anthrax was identified on Friday, March 3.
A second property at Nyah has been quarantined after a suspected anthrax case was reported on Saturday. Results from testing are expected this week.
The last case in the Swan Hill area involved a single cow in 2002.
Victoria’s chief veterinary officer Charles Milne told Country News about 20 of 200 ram lambs were reported as having died suddenly prior to anthrax being confirmed on the first property.
‘‘To date, two animals have tested positive for anthrax,’’ Dr Milne said.
‘‘The unexplained deaths of ram lambs had prompted the property owner to engage their private veterinarian.’’
Cattle and sheep on adjoining properties were being vaccinated last week; this was expected to be completed by Friday, March 10.
More than 1100 sheep were vaccinated on the infected property.
Asked what may have precipitated the outbreak, Dr Milne said it was not known what specifically precipitated this outbreak.
‘‘Anthrax is an infectious bacterial disease of animals, caused by the spore-forming bacteria Bacillus anthracis.
‘‘The spores of B. anthracis can lie dormant in the soil for decades and are capable of infecting animals which graze on contaminated areas.
‘‘Disturbance of soil by flood damage or ploughing may expose previously buried spores.
‘‘Anthrax incidence is likely to be related to temperature and rainfall, but the relationship is not properly understood.
‘‘Climate can also influence the way in which an animal comes into contact with the spores, for example, animals graze closer to the soil in dry periods when grass is short or sparse and herds may be moved to contaminated sites when water becomes scarce.’’
Dr Milne said irrespective of where they were located in Victoria, livestock owners were encouraged to immediately report sudden deaths of livestock, at any time of the year, to local Agriculture Victoria animal health staff, their private veterinarian or the all-hours Emergency Animal Disease Watch Hotline on 1800675888.
Meanwhile, biosecurity officers in Queensland are attempting to contain an anthrax outbreak that has caused the death of 80 cattle on a St George farm.
The last case of anthrax in Queensland was in 2002 and was successfully contained, with the bacteria appearing more frequently in NSW.