ovine brucellosis - leading sheep

Ovine brucellosis

Louise Mullemeister

Senior Veterinary Officer

Biosecurity Queensland

Roma

Brucellosis

Species Host Presence

Brucella ovis Sheep Occurs in Australia

Brucella suis* Pigs Occurs in Australia

Brucella abortus* Cattle Exotic

Brucella melitensis* Goats Exotic

Brucella canis* Dogs Exotic

*Potentially zoonotic

Ovine brucellosis

• Reduced semen quality & increased ram

turnover

• Poor conception rates

• Reduced lamb marking percentage

• Extended lambing period

– Pasture management & supplementation

– Metabolic disorders & mismothering

– Wool length & quality

– Lamb weights & condition scores

• Abortions (uncommon)

Economic impact

• Ram to ram

– Indirectly via ewe

• Passive venereal transmission

– Directly

• Sodomy

• Licking prepuce

• Ram to ewe (uncommon)

Transmission

Reproductive anatomy

Reproductive anatomy

Symptoms

Symptoms

Not all rams infected with ovine brucellosis will have palpable abnormalities.

Not all palpable abnormalities are due to ovine brucellosis.

• Complement fixation test (CFT)

• Semen culture

• Post mortem & culture of reproductive organs

Diagnosis

• Not a notifiable disease in Qld

• No regulatory control

• No enforced eradication/control program

• Voluntary Ovine Brucellosis Accreditation

Scheme

– Flock & property biosecurity measures

– Clinical examination & testing regime

Control/eradication

With regards to the Ovine Brucellosis Accreditation

Scheme, who:

• Has an accredited flock

• Only buys rams from an accredited flock

• Isn’t accredited & doesn’t buy from accredited

flocks?

Poll

Eradication

• Culling & replacing entire ram flock

• Identifying, testing & culling infected animals

• Combination of control & eradication programs

Control

• Using additional rams at joining

• Manual palpation of rams prior to joining

• Extending joining period

• Regular turn-over of rams

• Weaning prior to joining

Control/eradication

Program considerations:

• Sheep-proof fencing

• Clean musters

• Individual identification of rams

• Prompt removal of infected rams

• Avoid joining period

• Consistent testing intervals

• Test straying animals

• Buy rams from accredited flocks/tested prior to entry

Seek veterinary advice first

Eradication

Flock & property biosecurity

• Sheep proof fences

• Livestock records

• Isolation from unknown, unaccredited, infected

sheep

• Management of straying sheep

• Source sheep from OB accredited flocks

• Isolate & test introduced sheep

Prevention

Questions?

Slide 1: http://www.nzva.org.nz

Slide 3: http://dpi.nsw.gov.au;

http://australiandorper.com.au;

http://www.dpi.qld.gov.au;

http://www.whitesuffolk.com.au

Slide 6, 7, 8 & 9: http://dpi.nsw.gov.au

Slide 10 & 11: http://fao.org;

http://flockandherd.net.au

Slide 13: http://sheepconnectsa.com.au

Slide 14: http://oie.int

Image references