Completed Research Projects - Pigs
Reducing antibiotic usage in pig herds
Peri-urban and remote pig surveillance - Biosecurity Surveillance
Gilt Progeny
Growth Performance of Gilt Progeny
Reducing antibiotic usage in pig herds: controlling Lawsonia intracellularis by vaccination, housing and hygiene
Farm Animal & Veterinary Public Health Staff
- Dr Trish Holyoake
- Associate Professor David Emery
National Collaborators
- Dr Alison Collins, Elizabeth Macarthur Agricultural Institute
- NSW Department of Primary Industries
- Boehringer Ingelheim Pty Ltd, Australia
PhD Student
Ms Megan Donahoo
Summary
Proliferative enteritis (PE) is a major disease in the global pig industry. It is caused by Lawsonia intracellularis and is currently prevented by feeding pigs antibiotics. The project will provide two scientists (APAIs) with training in epidemiology and immunology applicable to livestock industries and biosecurity.
The ultimate aim of the project is to reduce antibiotic use on pig farms to make the pork industry in Australia more globally competitive, and to benefit human health by reducing the risk of amplifying strains of antibiotic-resistant bacteria.
There are three complementary streams of the research plan. The first stream will provide essential research to maximise the adoption of a commercial vaccine (Enterisol® Ileitis, Boehringer Ingelheim) as an alternative to antibiotics to control PE. Experiments will be undertaken to improve the efficacy of Enterisol® to control PE under Australian pig management systems and to induce immunity to Australian field isolates of Lawsonia intracellularis (LI).
In particular, we will:
- Measure the protective efficacy and the immune response of vaccinated pigs against Australian LI isolates;
- Increase the ability of the vaccine strain of LI to induce an effective immune response in vaccinated pigs by modifying its administration (extending the "antibiotic-free" window);
- Identify the antibiotics that do not interfere with the vaccine strain of LI's ability to infect pigs, hence allowing producers to continue to medicate in the face of concurrent disease while they vaccinate against LI;
- Establish the feasibility of vaccinating pre-weaning as an alternative to post-weaning as a way of avoiding the inherent post-weaning problems of concurrent medication and ease of administering vaccine through bulk water-delivery systems;
- Elucidate immune "markers" of protection to provide the commercial partner, veterinarians and pig producers world-wide with an objective measure of vaccine efficacy.
The second stream will compare the infection dynamics of LI in pigs reared in "traditional" concrete-based housing and in increasingly popular, welfare-friendly, bedded housing, so management strategies can be developed to control PE in these systems, as an adjunct to vaccination.
The third stream will provide accurate and definitive data on the impact of PE on the pig industry in Australia, including the seroprevalence of LI infection on farms in Australia, the cost of antibiotics used to control PE and direct measures of the effect of LI infection on pigs' carcass composition using a CT scanner. This data will provide accurate information on the impact of LI infection on the use of antibiotics and the profitability of the Australian pig industry and so supply the rationale to vaccinate and/or modify management to reduce antibiotic use.
Source of Funding
Australian Research Council Linkage Grant
Project Timeframe
February 2006 - December 2008
Peri-urban and remote regional surveillance for biosecurity within the pig industry in Eastern Australia
Farm Animal & Veterinary Public Health Staff
- Dr Trish Holyoake
- Dr Jenny-Ann Toribio
- Dr Marta Hernandez Jover
- Dr Fortune Sithole
PhD Student
Mrs Nicole Schembri
National Collaborators
- Department of Agriculture, Fisheries and Forestry
- NSW Department of Primary Industries (DPI)
- Victorian DPI
- Queensland DPI
- SA DPI & Resources
- WA Department of Agriculture
- Rural Lands Protection Board
- QAF Meat Industries
- Australian Pork Ltd
Summary
Preliminary studies have found disturbing gaps in our ability to identify and monitor pig health in a significant sector of the pig-rearing community in Australia - the small-scale pig producers in peri-urban and regional areas. Currently pigs raised in small-scale enterprises pose a high risk to Australia 's animal health industries due to our lack of knowledge about their movements and health and of the management practices implemented in these herds.
In this project we will develop systems to minimise the risk of exotic disease occurring in Australia by targeting this sub-population of the pig-rearing community.
In particular work will focus on:
- Identification of the locations and practices of peri-urban pig producers.
Improved methods for tracking pig movements.
Mechanisms for health surveillance.
Improved extension in relation to disease detection and swill feeding.
Source of Funding
Australian Biosecurity Cooperative Research Centre for Emerging Infectious Disease
Project Timeframe
February 2005 - August 2008
Improving the performance of gilt progeny: the role of immunity
Farm Animal & Veterinary Public Health Staff
Dr Trish Holyoake
National Collaborators
QAF Meat Industries
NSW Department of Primary Industries
PhD Student
Ms Yvette Miller
Summary
Preliminary research provides strong evidence to indicate that immune differences may be crucial to the health and observed growth differences of gilt and sow progeny.
The deliverables of this project include:
- An Australian data set demonstrating that gilt progeny reared on sows can perform equally in terms of growth performance to slaughter relative to sow progeny
Identification of immune and/or nutritional/orexigenic parameters in colostrum and/or milk from sows that are likely to be responsible for providing this subsequent growth performance advantage to their progeny-relative to gilt colostrum and/or milk - Evidence to support or disprove the hypothesis that any differences in the passive immunity provided to the progeny of sows relative to gilts is the result of a difference in their innate immunity and/or a difference in how they respond to active immune system challenge
- Determination of any differences in the immune response of the progeny themselves to a novel antigenic challenge (tetanus toxoid)
Outcomes from the project will lead to recommendations for on-farm management strategies, commercial opportunities for pharmaceutical and nutrition companies and links into other Pork CRC research (as outlined below)
Source of Funding
Pork CRC
QAF Meat Industries
Project timteframe
July 2007 - June 2008
Management strategies to improve the growth performance of gilt progeny
Farm Animal & Veterinary Public Health Staff
Dr Trish Holyoake
National Collaborators
QAF Meat Industries
NSW Department of Primary Industries
PhD Student
Ms Yvette Miller
Summary
The proposed project seeks to develop intervention strategies to improve the growth performance of gilt progeny. The first experimental stream will provide data to support or discount the feeding of supplementary milk to the progeny of gilts prior to weaning at two seasonal extremes (summer and winter) as an aid to improving their growth performance. This study will also provide baseline information on birth weight, growth parameters (weight gain, feed efficiency, morbidities, mortalities, carcass variation) and milk production and intake differences between the two sub-populations that will assist us to understand why there are the growth performance differences and determine how we might manipulate these differences to improve growth performance in the future. As a sideline, it may also assist us to improve sow longevity, through improved farrowing house management.
The outcomes of the second experimental stream will include:
- Determining the importance of PE as a performance limiting factor on farms
- Provide baseline information that would support the decision on whether to vaccinate gilts and/or sows prior to farrowing against PE
- Provide information that would support or disprove the medication of sows around the time of farrowing to reduce the transmission of LI infection to progeny
- Determine if there is a need to vaccinate both gilt and sow progeny against LI infection to prevent PE
- Measure the relative infection rates of gilt and sow progeny as a guide to potential benefits from rearing the two sub-populations separately
Source of Funding
Pork CRC
QAF Meat Industries
Project timteframe
July 2007 - June 2008