Description
2005 – Manipulating Pig Production X
The Xth Biennial Conference of the Australasian Pig Science Association (Inc.) was held at the Christchurch Convention Centre, Christchurch, New Zealand from 27–– 30th November, 2005. During the conference, about 100 one-page papers, seven reviews and two symposia were presented covering issues ranging from pig nutrition through to pig health, welfare, housing and reproduction. Below is a summary of the review and symposia papers.
A.C. Dunkin Memorial Lecture
Coping strategies for the modern scientist
By F.R. Dunshea
In the Dunkin Memorial Lecture, Professor Dunshea outlined what he believed were the strategies required of scientists to cope and be successful in the modern and ever-changing research environment. Professor Dunshea stressed the need for the modern scientist to:
- understand and apply the basic principles of the scientific process;
- develop an appreciation for the history of scientific endeavours and where, as a scientist, they sit in this line of history;
- appreciate their mentors and give freely to their protégés;
- establish collaborations with other scientists who can complement their skills and expertise;
- be prepared to change disciplines and travel to extend their training;
- communicate and publish their work and;
- achieve all of the above in a responsible manner.
Review I
Mechanisms for modification of porcine growth by beta-adrenergic agonists
By H.J. Mersmann
In this review Dr Mersmann outlined the actions of oral beta-adrenergic receptor agonists, such as ractopamine and how these agonists can be used to improve pig productivity. Through the review, Dr Mersmann showed how in pigs, beta-adrenergic agonists have been shown to increase growth rate and deposition of skeletal muscle while reducing the proportion of carcass fat. However, the effect of beta-adrenergic agonists decreases over time.
Review II
Gene markers and how they can be used in selection
By C. Moran
Professor Moran discussed the current state of porcine genomic studies. He anticipated that mapping of the porcine genome sequence would be completed by the end of 2006, however full annotation of the sequence could take longer. Professor Moran explained the completed genome sequence will have a major impact on the way porcine genomics and genetic studies are performed in the future. In addition, the genome sequence will accelerate the discovery of genes and mutations that currently have a significant economic impact on the pig industry.
Review III
The impact of air quality on animal health
By P.K. Holyoake
Dr Holyoake discussed how airborne contaminants, which are generated when animals are housed densely in confinement, impact on animal health and productivity. In addition, Dr Holyoake examined the potential human health hazards of airborne contaminants for workers in intensive animal production systems. The structural and functional defence mechanisms of the respiratory tract that enable animals to cope with atmospheric contaminants were also discussed. Dr Holyoake concluded that routine air quality monitoring was needed to highlight when management and work practice changes should be implemented to keep contaminant levels within safe limits for livestock and animal workers. A measurement system for airborne contaminants is currently being developed in Australia.
Review IV
Role of dietary non-starch polysaccharides in pig nutrition
By W.J.J. Gerrits and M.W.A. Verstegen
The interest in the role of dietary fibre or non-starch polysaccharides (NSP) in pig nutrition is increasing. NSP improve gut transit and reduce stomach ulcers and in sows and growing pigs some NSP sources reduce energy expenditure on physical activity. It is also thought that NSP affect the behaviour of pigs and this in turn could be used to assess their welfare. The reviewers concluded that further research was necessary to determine how and why a NSP diet affects behavioural responses and, possibly, the welfare of pigs. They also concluded that more knowledge on the biological mechanisms behind the effects of dietary fibre would be important for future feed evaluation. It is likely that the effects of dietary fibre depend on the chemical and physical properties of the chemical fraction.
Review V
A review – group housing for gestating sows – strategies for a productive and welfare friendly system
By R.S. Morrison
Dr Morrison outlined the animal production and welfare issues associated with group housing of sows. She explained how future welfare requirements would likely see sows housed in a group environment for at least part of their gestation. Dr Morrison showed how group housing enabled sows to move more freely and how this could improve sow welfare by increasing social contact among animals. However, she also showed how group housing could lead to heightened aggression between sows, and that this could impact negatively on animal welfare and reproductive performance. Dr Morrison also highlighted the many issues still to be resolved regarding group housing – including determination of the optimum space requirements of sows in group systems and the need to fine-tune the management of housing systems.
Review VI
Recent advances in understanding mycotoxicoses in swine
By T.K. Smith, G. Diaz, and H.V.L.N. Swamy
Professor Smith described the major mycotoxins that impact on pig production and health in the Australasian region. He also showed how mycotoxins could interact synergistically to affect pig performance.
Review VII
Pork as a functional food
By D.N. D’Souza, B.P. Mullan and F.R. Dunshea
In many developed countries there is increasing concern about the health status of the human population, and in particular the proportion of people who are overweight or are at higher risk of developing cancers and cardiovascular diseases. The reviewers discussed some of the nutritional characteristics of pork that are beneficial to human health and outlined the evidence available showing how pork could be used as a functional food to reduce the incidence of obesity and some human diseases. Dr D’Souza concluded that the success of pork as a functional food may ultimately be determined by how well it is promoted and marketed.
Symposium 1
Health Strategies for the Modern Pork Industry
The papers presented in this symposium were:
Disease control challenges for the pig industry – what will the future bring?
By R.S. Morris
Vaccines – what are the future options for health and disease control?
By S.J. Driesen, V.A. Fahy, and P.M. Mitchell
Management for health – on farm issues and cost benefits By E.B.M. Welch
This symposium examined what the future may hold in regard to pig health. The contributors discussed opportunities for vaccine use in the future and the current health management strategies that are available to assist commercial pig producers to control the spread and impact of pig pathogens. The first paper examined disease control challenges for the pig industry. Professor Morris explained how there will be some unpleasant surprises in the disease problems we face and that these problems will catch us unaware. In the second paper Dr Driesen examined vaccines and their role in pig production in the future. He showed how vaccines could improve animal welfare and reduce the cost of production through improved growth rates and feed conversion efficiency. In the final paper, Dr Welch offered strategies to manage the challenges associated with maintaining the health status and productivity of pigs: close monitoring of pig body condition, feed intake and the environmental and housing conditions of sows; management, intervention and supervision during the farrowing process; conversion to all-in all-out production; batch farrowing and age segregation; ensuring a successful weaning process; monitoring of the environment to ensure adequate air flow and quality for intensively housed pigs and; the use of deep litter production systems.
Symposium II Gilt Management for Lifetime Performance
The papers presented in this symposium were:
Biological and economical evaluation of sow longevity By D.L. Levis
Management and nutritional factors affecting puberty attainment and first litter size in replacement gilts
By W.H.E.J. van Wettere, M. Mitchell, D.K. Revell and P.E. Hughes
Gilt management practices – a commercial case study By R.J. Smits, K. Shaw and L.J. Johnston The reviewers showed how sow replacement rate has increased over the past few decades and how this has inevitably caused an increase in the proportion of premature sow culls in modern pig production systems. The main objectives of the symposium were to i) identify the costs associated with a high sow turnover; ii) review current recommendations for gilt management and iii) consider alternative management strategies that may promote sow longevity and hence raise lifetime performance. In the first paper, Dr Levis examined the biological aspects associated with sow replacement of the herd base, including structured selection, age at first mating and parity performance. He concluded that a commercial sow piggery should keep sows producing at a high level for as long as possible. In the second paper, Dr van Wettere showed how the current level of gilt reproductive failure is unacceptably high and suggested this was because modern gilt genotypes, despite being inherently different from their counterparts of 20-30 years ago, are still managed the same. To improve reproductive performance of gilts, the contributors suggested that the current management recommendations should be modified to better suit the modern, leaner genotypes. In the final paper, Mr Smits used a commercial case study to highlight how current gilt management recommendations are not suited to the modern lean genotypes.