Bovine respiratory disease

Bovine respiratory disease (BRD) is the most common cause of illness and death in Australian feedlot cattle. It is most common in the first four weeks after entry to the feedlot.

BRD is caused by a combination of stress and disease-causing agents, including viruses and bacteria.

Conditions when BRD is likely to occur

• During the first four weeks when cattle enter a feedlot , if they have not been properly prepared or ‘backgrounded’. Unstressed cattle on pasture are rarely affected.
• During stressful conditions including:
  • recent weaning
  • saleyards
  • transport
  • injury
  • dehydration
  • co-mingling, pen competition, pen 'add-ons' and movements
  • handling
  • weather extremes and dust
  • feed and water changes.

Identification and diagnosis

Early identification of affected cattle is vital, and pens of cattle should be checked daily.

Clinical signs that would lead you to suspect bovine respiratory disease include the following:

• depression and loss of interest in surroundings
• lethargy and unwillingness to move
• extended head
• droopy ears
• discharge from the eyes, nose and mouth
• coughing
• rapid shallow breathing.

Diagnosis of the disease-causing agents involved in bovine respiratory disease on your property will require assistance from your veterinarian. Knowing the specific cause allows specific prevention strategies and treatment protocols to be put in place.

Prevention

An integrated approach to prevent bovine respiratory disease should consider the following:

• reducing stress on cattle in the first four weeks in the feedlot
• improving adaption of cattle to the feedlot environment by selecting cattle directly from breeders and producers who yard wean calves and by backgrounding cattle prior to entry to the feedlot
• vaccinating against respiratory diseases during backgrounding
• avoiding sudden feed and water changes
• minimising pen ‘add-ons’ and movements.