New Research On Pneumonia In Sheep Underway

We are pleased to announce that we have received funding from the Australian sheep industry through Meat & Livestock Australia and Animal Health Australia for an abattoir survey of ovine pneumonia/pleurisy pathogens in Australian sheep flocks.

Previous research conducted by our team has uncovered a high prevalence of Australian sheep flocks with pneumonia, with 50 per cent of the lines of lambs examined at an abattoir in South Australia having evidence of the disease. Our research indicates that geographic location and age, but not breed, may be significant risk factors for pneumonia in Australian lambs.

The National Sheep Health Monitoring Project data also indicate that up to 50 per cent of Australian sheep flocks have a problem with endemic pneumonia.

During 2018-19 Joan Lloyd Consulting Pty Ltd and Meat & Livestock Australia co-funded pilot research on pneumonia pathogens circulating in Australian sheep flocks. This project was focussed on method development, including culture and PCR (polymerase chain reaction), and has revealed widespread infection with Mycoplasma ovipneumoniae in Australian slaughter lambs sampled at abattoirs in South Australia and New South Wales.

M. ovipneumoniae is a primary respiratory pathogen of sheep first isolated from a sheep flock in Queensland in the 1960s that had shown poor growth rates and reduced exercise tolerance for some years. It has subsequently been found in most sheep raising countries internationally.

M. ovipneumoniae can cause both primary pneumonia and predispose to secondary infections with other bacteria (Mannheimia haemolytica, Pasteurella multocida, Biberstenia trehalosi). Infected sheep develop nasal discharge, inner ear infection (ear droop), coughing, reduced exercise tolerance and poor growth rates. Chronic infections are common, with bacteria persisting in the nasal cavities, pharynx, inner ear, and lower airways/lungs. Infection passes from the ewe to the lamb soon after birth. The lamb:ewe ratio is significantly reduced in flocks infected with M. ovipneumoniae. Chronic infection may also lead to increased ewe mortality.

The current project will build on our previous research findings and provide information on the prevalence of the ovine respiratory pathogens circulating in sheep flocks in south eastern Australia.

This will provide comprehensive understanding of the aetiological agents involved in pneumonia in Australian sheep and help underpin the development of control measures.