The Scottish-born vaccine which transformed global flock health

The vaccine is recognised worldwide as one of the most significant contributors to sheep and cattle health
The vaccine is recognised worldwide as one of the most significant contributors to sheep and cattle health

A vaccine developed by Scottish scientists which has transformed herd and flock health for farmers over the last 25 years is being brought into focus.

The Mannheimia (Pasteurella) haemolytica vaccine, one of the most significant global advances in livestock vaccination, will be in the spotlight as part of the RHASS Presidents' Initiative for 2023.

The initiative aims to raise awareness of the role of science through a series of case studies in the lead up to the Royal Highland Show, which will highlight examples of farmers benefiting from these advancements.

Developed at the Moredun Institute by Professor Willie Donachie and his research team in 1997, the vaccine owes its success to the novel discovery that to survive, the bacteria needed to be able to access iron.

From this, he developed a new technique that significantly reduced the occurrence of pneumonia in lambs and calves.

Although a vaccine existed previously, it was not effectively immunising against all 15 strains of Pasteurella. The transformation came from Professor Donachie’s understanding of the disease pathogenesis.

Fundamentally, he recognised that if the vaccine cells could be grown to produce IRPs replicating the conditions in the sheep’s body, it would trigger a protective immune response in the live animal.

“Vaccinations are prevention rather than cure, and it was important to get a vaccine that could cover all strains of P.haemolytica in one," he said.

"It was a really exciting time using new technologies to make new discoveries, and strange as well because we were working on something game changing we but couldn’t talk about it to anyone while the development was ongoing.

"We were fortunate: it was the right people and the right time, and, like all my research and work over 37 years at Moredun, it was the fantastic opportunity to work collaboratively with farmers.”

The vaccine was patented and developed commercially in partnership with Hoechst Animal Health, with the main royalties from the patent dedicated to funding future research and development at the institute.

A proportion was also shared between the core research team and all the staff working at Moredun at the time.

Launched in 1997 as part of a multivalent vaccine that also immunises against clostridial diseases, the vaccine is recognised worldwide as one of the most significant contributors to sheep and cattle health.

Hill livestock farmer, Andrew Houstoun, who farms 1100 breeding ewes and 160 Angus cattle in Highland Pertshire, said the vaccine was vital for the way he farmed.

“This is essential for our system as we have sheep out on the hill and across a number of other farms and farming extensively like this, we can’t keep a close eye on all the sheep all the time and may miss signs of declining health.

"We’d be lost without it - it’s easier management for us, it keeps treatment costs and losses down, and productivity up.

"There are a lot of challenges in sheep farming at the moment between rising feed costs, lack of labour and profitability, but one thing we are lucky with is health.”

RHASS Presidents’ Initiative Honorary President, Ian Duncan Millar, a sheep farmer and ambassador for sheep health research, said the vaccine was an "extraordinary step in science".

"[It] is a testament to the importance of continuous scientific research and development to support optimal farming and food production.

"Willie and the Pasteurella team are often unsung heroes, but they’ve contributed enormously to global livestock high health, and exemplified how collaborative science and farming both carve out a legacy and define the future.”

Professor Donachie was awarded an OBE in 2016 for services to animal and veterinary biosciences.