Reducing pig herd antibiotics

Dr Alison Collins believes controlling ileitis by vaccination, and improved housing and hygiene may reduce antibiotic use in pig herds.

Dr Alison Collins believes controlling ileitis by vaccination, and improved housing and hygiene may reduce antibiotic use in pig herds.

Research underway will help the Australian pork industry better manage a disease in growing pigs now prevented by antibiotics.

NSW Department of Primary Industries (DPI) investigator, Dr Alison Collins, said a new three-year research project was examining ways of reducing antibiotic use in pig herds by controlling ileitis by vaccination, and improved housing and hygiene.

In the US and Europe, a commercial vaccine is used as an alternative to antibiotics to prevent the wasting disease ileitis, which affects growing pigs aged between six and 20 weeks, but which can also cause sudden death in young breeding stock.

The disease is caused by the bacteria Lawsonia intracellularis (LI) and is estimated to cost Australian pork producers as much as $7 per pig, adding almost five per cent to production costs.

The $1 million project, funded by the Australian Research Council, is a collaboration between NSW DPI, the University of Sydney (Dr Trish Holyoake and Dr David Emery) and a vaccine manufacturer.

The project aims to deliver options for reducing incidence of the disease, as well as finding alternatives to antibiotic use.

The research has three components:

  • Experiments to better understand the disease and to optimise the efficacy of a commercial vaccine to control ileitis under Australian conditions,
  • A study of the effect of housing type on the incidence and spread of LI infection in pigs,
  • A survey of commercial pig producers and veterinarians to provide accurate data on the impact of ileitis on pig performance and farm profitability.

"We will be looking at the prevalence of LI infection on farms, the cost of antibiotics used to control ileitis, and at the effect of LI infection on pigs’ carcasses,"; Dr Holyoake said.

To examine the impact of the disease on the growth of the pigs, the researchers will make use of a CT scanner at DPI’s Elizabeth Macarthur Agricultural Institute at Camden.

"This will provide an accurate measure of the impact of ileitis on pig growth and carcass composition, and therefore on the profitability of the Australian pig industry," Dr Collins said.

Dr Holyoake said the research includes examining the incidence of LI infection in pigs reared in concrete-based housing, compared with increasingly popular, welfare-friendly bedded housing.

There is currently no information on the incidence or impact of this disease on pigs reared in these bedded systems.

"This will enable management strategies to be developed to control ileitis in these systems along with the traditional intensive systems, as an adjunct to vaccination," she said.