Interactions between beef cattle and simulated tuberculous possums on pasture.

Area of Science:

• Veterinary Science
• Wildlife Ecology
• Infectious Disease Transmission

Background:

• Brushtail possums (Trichosurus vulpecula) are known reservoirs for Mycobacterium bovis.
• Understanding wildlife-livestock disease transmission is crucial for disease control.

Purpose of the Study:

• To assess the risk of Mycobacterium bovis transmission from brushtail possums to cattle.
• To analyze cattle behavior and contact patterns with potentially infectious possums.

Main Methods:

• Sedated possums mimicking illness were observed with cattle in a controlled area.
• Behavioral analysis recorded cattle proximity, investigation, and physical contact duration.
• Eight observation periods were conducted to document interactions.

Main Results:

• Cattle were attracted to moving possums from over 50m, investigating them for 34% of observation time.
• Seven to eight cattle made physical contact with possums per period, including sniffing and licking.
• Contact patterns indicated a high risk of aerosol transmission of Mycobacterium bovis.

Conclusions:

• Moving, ill brushtail possums pose a significant risk for Mycobacterium bovis transmission to cattle.
• Direct physical contact and proximity facilitate potential infection, particularly via respiratory routes.
• Cattle behavior, including habituation, influences individual risk exposure.