RIRDC Completed Projects in 2000-2001 & Research in Progress as at June 2001

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EGG PROGRAM - COMPLETED PROJECTS
PROJECT No	PROJECT TITLE	RESEARCHER	PHONE	ORGANISATION

* Indicates a joint chicken meat and egg program project. These projects will appear in both sections of this report.
 

Implications of the Changing Economic Environment for the Australian Egg Industry
 

AEI-8A/ AEI-9A	National industry databases
IMS-3A	Review of information sources used by Australian rural industries and egg industries overseas

Flock Health and Disease Management
 

BIR-1A	Layer industry disease and management survey
BTT-2A*	Revision of the AUSVETPLAN Disease Strategy document on very virulent Infectious Bursal Disease
CSA-4J*	Postgraduate Scholarship – Matthew Rudd: Identification of virulence determinants of infectious bursal disease virus (IBDV)
CSA-7J*	Therapeutic applications of chicken interferon gamma in poultry
DAN-159J*	NDV vaccination strategies aiming to induce high HI titres in elite breeding and layer flocks
DAQ-244J*	Investigations into the management of the darkling beetle, Alphitobius diaperinus (Panzer)
RMI-6J*	The development of effective immunisation strategies against Marek’s disease
RMI-8J*	Characterisation of very virulent Australian isolates of Marek’s disease virus
UM-37A	Development of a live attenuated vaccine for chicken anaemia virus
UTS-3J*	Postgraduate scholarship – David Witcombe: Production and characterisation of recombinant antigens of Eimeria

Feed Availability and Nutrition
 

DAQ-241A	Alternative protein sources for laying hens
GRD-1J*	Premium Grains for Livestock Program
US-54A	Amino acid and energy requirements of imported IsaBrown laying hens

Husbandry and Welfare
 

US-71A

Development of a non-invasive test of stress in laying hens

Environmentally Sustainable Management
 

UNE-59A

Environmentally acceptable land use for chicken meat and egg production


Implications of the Changing Economic Environment for the Australian Egg Industry
 

Project Title	National industry databases
RIRDC Project No:	AEI-8A and AEI-9A
Researcher:	Mr Hugh McMaster
Organisation:	Australian Egg Industry Association (AEIA) PO Box 569 HURSTVILLE  NSW  1481
Phone:	(02) 9570 9222
Fax:	(02) 9570 9763
Email:	enquiries@aeia.org
Objectives	·    To provide the industry with important statistics by the continuation of existing databases ·    To analyse and interpret the outlook for the industry on the basis of more comprehensive and timely data and therefore the opportunity to provide the industry with more relevant information on the market outlook ·   To collect and collate information of national relevance to the Australian egg industry ·    To disseminate information collated to egg producers, marketing organisations, egg products manufacturers and government personnel
Background	The Australian egg industry has few available resources for the development of nationally based statistics.  The manner in which egg production is planned and the inelastic demand for eggs means the industry is extremely vulnerable to volatile swings in profitability.  The development of statistics will assist in providing a better understanding of the market environment.  This will assist in the development of appropriate strategic responses through revised production planning aimed to increase industry profitability.
Outcomes	Improved industry statistics due to the continuation of existing databases and the production of an annual statistical publication. Also the opportunity to analyse and interpret the outlook for the industry on the basis of more comprehensive data and, therefore, the opportunity to provide the industry with more relevant information on the market outlook.
Benefits	It is expected that the entire Australian industry will benefit from these databases.  This is because information to be collected is considered to be relevant to the industry and is capable of regular dissemination. Possible indirect benefits may arise on the basis that a more profitable and less volatile industry may create a more certain investment climate and, thereby, facilitate adoption of more environmentally sustainable production methods.
Communication	The chick placements data was communicated to the industry on a monthly basis through the RIRDC – Egg Program newsletter “Focus on Research”.  Analysis of the economic outlook was presented verbally to the industry at a series of meetings throughout the country.  The annual statistical publication and the final report for the project will be made available as RIRDC publications.

Project Title	Review of information sources used by Australian rural industries and egg industries overseas
RIRDC Project No:	IMS-3A
Researcher:	Mr John O’Connor
Organisation:	Industry Management Services Pty Ltd Level 2 470 Collins Street MELBOURNE  VIC  3000
Phone:	(03) 9629 6287
Fax:	(03) 9629 2289
Email:	johnoconnor@access.net.au
Objectives	·    To prepare a review of information sources used by rural industries in Australia and by egg industries overseas. ·  To prepare a presentation and attend an industry databases workshop to be held in Sydney on 7 May 2001.
Background	As with other agricultural industries, the egg industry needs certain statistical collections for the purposes of business planning and policy analysis.  There is a particular need for statistics that assist with production forecasting because egg price fluctuations are mainly caused by fluctuations in supply, not fluctuations in demand.  The purpose of this project is to provide some of the information that will assist the industry to make decisions about the statistical collections to be made in the future, and the methods to be used to collect and publish those collections.
Research	The main part of the report is a comprehensive listing of statistics collected for the Australian pig, dairy and wool industries, and for the egg industries of New Zealand, the UK, the USA and the Netherlands.
Outcomes	The above listed examples confirm that the Australian egg industry compares unfavourably with other industries in the extent of its statistical collections and the availability of economic information such as farm physical and financial data. In the UK, the USA and the Netherlands, the egg industries are supplied with comprehensive statistical services by government agencies.  In the UK and the USA, these are supplied entirely at the governments’ expense.  In the Netherlands the cost is split between the government and the industry.  In addition to the statistical collections, there is a substantial amount of information about farm costs, returns and performance benchmarks in these three countries.  In New Zealand, the situation is much like that in Australia, with minimal contribution from the government and a very limited range of collections. The other Australian industries reported also have more extensive collections than the egg industry.  To some extent this is because they are treated more generously by government agencies, but the main reason is that these industries organise and fund collections from their own resources. In some circumstances, valuable statistical series can be collected at moderate cost by using a properly constructed sample survey rather than a full survey of firms in the relevant sector.
Implications	This report provides a comprehensive illustration of the options available as demonstrated by other industries.  The next, and more difficult stage, is for the industry to make judgements about the purposes for various collections and whether the cost can be justified in terms of the benefits they might confer.


Flock Health and Disease Management
 

Project Title	Layer industry disease and management survey
RIRDC Project No:	BIR-1A
Researchers:	Dr Peter Groves                                           Dr George Arzey
Organisation:	Birling Avian Laboratories 642 Great Western Highway PENDLE HILL  NSW  2145 NSW Agriculture MENANGLE  NSW  2568
Phone:	(02) 9842 1105                                               (02) 4640 6402
Fax:	(02) 9688 4015                                               -
Email:	EMAIL: peter_groves@baiada.com.au    george.arzey@agric.nsw.gov.au
Objectives	·         To provide prevalence information on diseases present in the layer industry. ·         To look for epidemiologic associations between disease and management/environmental factors. ·         To look for correlations between disease prevalence, stress, performance and management factors. ·         To provide industry with a better appreciation of the value of performance recording, disease monitoring and interactions of management practices and flock health and welfare.
Background	This survey was conducted over a two year period (July 1995 through June 1997) across the layer industry in NSW and Victoria.  Particular disease agents chosen for attention were Mycoplasma gallisepticum (MG), M. synoviae (MS) , Infectious Bronchitis virus (IBV) and Avian Encephalomyelitis virus (AEV).  Attempts at assessing stress levels existent in flocks were also included within the survey’s data collection (differential white blood cell counts and the heterophil:lymphocyte ratio).  Information was also collected on nutritional specifications, lighting programs, coccidiosis control, feed and water space allowances, vaccination histories, cage stocking densities, bird breed, beak trimming severity, egg production and mortality.
Research	A random selection of 24 farms across NSW and Victoria was made, stratified across geographic locations.  The farms selected were visited 3 times over a twelve month period and up to 5 age groups were examined on each visit on each farm.  Each visit consisted of a clinical assessment of flock health and individual bird weights were measured on 30 to 60 birds in each age group. 12 blood samples were collected each time and tested for antibodies to MG, MS, IBV and AEV and differential white blood cell (WBC) count.  If clinical disease signs were present, samples for other pathogens as deemed appropriate were also collected.  A pooled faecal sample was collected and examined for presence of helminth eggs or coccidia.  Cage dimensions were measured, feed and water space recorded and light intensity at the feeder trough level measured.  Visual estimates of the severity of beak trim, the level of feather cover and findings from palpation of the ribs were recorded on each bird weighed.  A visual estimate of shell quality (colour and presence of abnormalities) was made at each visit. A questionnaire covering feed specifications, vaccination history, egg production and mortality history was completed over the 3 visits to each farm.
Outcomes	Descriptive statistics on many factors were obtained.  The period of study was notably affected by a number of epidemics, Marek’s Disease (MD) and Egg Drop Syndrome ’76 (EDS) in particular.  Performance differences between the existing local breeds and the more recent imported brown egg breeds were observed.  Differences in body weights of these breeds highlighted the importance of attention to welfare codes based solely on floorspace per bird rather than accounting for differences in weight per unit of floorspace.  Differences in serological responses of the breeds were also shown.  Some differences in performance between different production systems were also seen.  Numbers of birds per cage had little influence on feather cover, shell quality or heterophil:lymphocyte (H:L) ratios.  Floor production systems (free range or barn lay) elicited higher H:L ratios than did cage systems, possibly indicating higher stress levels in the former management systems.  Rib scores (a measure of osteoporosis) rose with age indicating skeletal calcium depletion with length of laying period.  Serological results indicated that MG entered flocks consistently in the early lay period, at a time when deleterious effects of infection could be considered to be the most serious.  Many farms were encouraged to adopt MG vaccination programs as a result.  IBV titres rose consistently during the laying period to a peak around 30-36 weeks of age indicating the presence of disease challenge in lay.  The introduction of continual IBV vaccination was an obvious recommendation from this finding.  The pattern developed for AEV serology raised concern as many farms do not vaccinate for this disease believing natural exposure in rearing provides protection.  Many flocks were found to seroconvert to AEV during lay.  Recommendations for proper protection by appropriate AEV vaccination was an obvious outcome. Associations between protein and calcium levels in some rearing rations with later production parameters (peak production and persistence of lay) were found. Cage space was found to be associated with flock uniformity and osteoporosis (as measured by rib palpation), surprisingly more space per bird giving poorer results.  Conversely, higher weight to space ratio was associated with poorer feather cover. More severe beak trimming was associated with a later onset of lay and on an individual cage basis, more severely trimmed birds were lighter than their cage mates. Stress levels (H:L ratio) and poor feather cover were shown to be associated leading to an hypothesis that poor feather cover may be a strong contributor to stress in layer chickens.
Implications	The survey provided backing for the need for importation of new vaccines (Marek’s Disease and EDS’76) to cope with the widespread outbreaks that occurred during the study period. The importance of considering bird weight in relation to cage density regulations for bird welfare was highlighted. The variances in serology and haematology may reflect a higher or more consistent exposure to pathogens with birds kept on the floor. The need for proper attention to vaccination was highlighted, especially in relation to
	the patterns seen with MG, AEV and IBV in layer flocks. Cage density appears to have considerable effects, with more room per bird being deleterious in regard to egg production, uniformity of body weights and osteoporosis. Consistency and severity of beak trimming appears to have enormous effects on bird welfare and commercial performance.  Due attention to the quality of this procedure would give enormous benefits to both concerns and should be given the highest priority of any bird management practice. The industry needs to recognise that poor feather cover is a major welfare issue, as well as being associated with poorer performance.  This area needs much more concentrated research to understand the factors involved.
Publications	Publication of results has been concentrated on feed-back to the industry: Layer disease and management survey.  Scientific Meeting of the Australian Veterinary Assoc., Poultry Information Exchange, Surfer’s Paradise, April, 1996. Survey on poultry health and management in the layer industry.  Queensland Poultry Science Symposium, Vol 5. University of Qld. Gatton, July, 1996. Factors affecting osteoporosis as measured by rib score in the layer industry survey.  Victorian Layer Production Seminar, VIAS, Attwood, Victoria, September 1997. Layer disease and management survey 1995-97: lifting our game.  Poultry Information Exchange, Surfer’s Paradise, April, 1998. Layer disease and performance survey - infectious bronchitis. Victorian Layer Production Seminar, VIAS, Attwood, Vic, September, 1999. Layer industry survey - stress management in layers.  Victorian Layer Production Seminar, VIAS, Attwood, Vic, September, 2000.


 

Project Title	Revision of the AUSVETPLAN Disease Strategy document on very virulent Infectious Bursal Disease
RIRDC Project No:	BTT-2A
Researcher:	Dr Clive Jackson
Organisation:	Biological Technology Transfer 2 Victory Avenue CAMDEN  NSW  2570
Phone:	(02) 4655 4007
Fax:	(02) 4655 4008
Email:	cawjacko@ozemail.com.au
Objective	·    To revise the AUSVETPLAN Disease Strategy document on very virulent infectious bursal disease.
Background	In 1998, Dr Jackson developed an AUSVETPLAN Disease Strategy Document as part of a consultancy to the DPIE.  That Strategy Document was developed because of the serious economic impact that very virulent Infectious Bursal Disease (vvIBD) would have on the poultry industry should it gain entry into Australia.  The annual loss was estimated to be in the order of $50 million.  A revised Strategy Document was developed using the Newcastle Disease (ND) Strategy Document as a model.  However, experiences gained through the implementation of that document to the 1998-2000 outbreak of virulent ND in NSW resulted in further revision of the Disease Strategy document for vvIBD.
Research	The revision was undertaken with the assistance of a corresponding committee of Australian scientific experts on IBD.  The Strategy Document was rewritten by the Principal Investigator to incorporate decisions from a Government/Industry meeting held on 19 August 1999.  The revised Strategy Document also considered the role player by government and industry during the 1998-2000 eradication of virulent Newcastle disease in NSW.  It also considered the new cost-sharing agreement for exotic disease control and eradication.
Outcomes	A revised Disease Strategy document has been developed for review by RIRDC Egg and Chicken Meat Programs.  The revised Strategy Document should provide the industry and government with a contemporary document on which to base an eradication program.  The Strategy Document takes into account the current funding arrangements for exotic disease control in Australia.  It attempts to define the resources required by industry and government.  It also provides industry with guidance in undertaking a risk analysis of the benefits to be derived from pursuing eradication with limited resources and funding.
Implications	The existence of a Disease Strategy document focuses the attention of the industry on the need to remain vigilant against the entry of vvIBDV.  It emphasises the need to continue to develop rapid diagnostic tests to detect the viruses as early as possible.  It also demands the availability of funds and resources to undertake the eradication program.
Publications	Jackson, CAW (2001) AUSVETPLAN Disease Strategy for Very Virulent Infectious Bursal Disease virus (vvIBDV) Eradication. Proc. AVPA Scientific Meeting 6-7.2.01 University of Sydney, p15. Jackson, CAW (2001) A Disease Strategy for the Prevention and Eradication of Very Virulent Infectious Bursal Disease Virus (vvIBDV). Proc. XIIth International Congress of the WVPA, Cairo, 17-21.9.01 (Abstract) (Submitted for publication).

Project Title	Postgraduate Scholarship – Matthew Rudd: Identification of virulence determinants of infectious bursal disease virus (IBDV)
RIRDC Project No:	CSA-4J
Researcher:	Mr Matthew Rudd and Dr Jagoda Ignjatovic
Organisation:	CSIRO Livestock Industries Australian Animal Health Laboratory (AAHL) Private Bag 24 GEELONG  VIC  3213
Phone:	(03) 5227 5769
Fax:	(03) 5227 5555
Email:	Jagoda.Ignjatovic@csiro.au
bjectives	·    To characterise and sequence a very virulent (vv) exotic strain of infectious bursal disease virus (IBDV) and identify genomic region(s) which may influence pathogenesis. ·     To compare and contrast the pathogenicity of attenuated and very virulent IBDV (vvIBDV) strains in vivo, and identify criteria which might differentiate between the two strains. ·     To establish a reverse genetics system for the recovery of infectious IBDV from cell culture, embryonating eggs and/or directly from SPF chickens. ·     To swap genomic material between attenuated and vvIBDV strains and assess the impact of such manipulations on pathogenicity in vivo.
ackground	Since first reported in 1989, vvIBDV has spread rapidly throughout Europe, Asia, and many other countries. Australia is currently free of such strains.  This project seeks to identify potential virulence markers of IBDV for the development of rapid and highly accurate diagnostic tests which could be used to detect any incursion of exotic vvIBDV strains, should this ever occur.
Research	An Indonesian vvIBDV strain was completely sequenced and the deduced amino acid sequences were aligned with the corresponding sequences of published IBDV strains to identify amino acids which are conserved solely in very virulent strains. An endemic attenuated IBDV strain (002-73) and an Indonesian vvIBDV strain (Tasik94) were both extensively characterised in vivo, and the ability of several biological assays to differentiate between the two strains were assessed. Genomic material, corresponding to a portion of the VP2 protein, was swapped between the attenuated 002-73 and very virulent Indonesian Tasik94 strains to generate recombinant IBDV. A reverse genetics system will be used to recover infectious recombinant virus. Pathogenicity testing of the recombinant virus will be used to assess the significance of putative virulence determinants identified and to provide valuable information which will assist in the development of a diagnostic assay.
Implications	Further work needs to be conducted to recover and assess recombinant virus(es).  The successful identification of virulence determinants is a prerequisite for developing diagnostic tests needed to monitor the field situation of IBDV in Australia.
Publications	Rudd, M.F., Heine, H.G., Parede, L., Sapats, S.I., Ignjatovic, J. (2001)  Characterisation of an Indonesian strain of very virulent infectious bursal disease virus (vvIBDV). Proc. Int. Symp. Infectious Bursal Disease Virus and Chicken Anemia. In press. Currently in preparation: Rudd, M.F., Heine, H.G., Middleton, D., Lowther, S., Ignjatovic, J. Differentiation between endemic and exotic strains of infectious bursal disease virus (IBDV). Poster in preparation for presentation at the 3rd Veterinary Virology Conference, 26-28th September 2001. Rudd, M.F., Heine, H.G., Sapats, S.I., Ignjatovic, J. Identification of putative virulence determinants of infectious bursal disease virus (IBDV).  Manuscript in preparation for submission to Virus Research.




Project Title	Therapeutic applications of chicken interferon gamma in poultry
RIRDC Project No:	CSA-7J
Researcher:	Dr John Lowenthal
Organisation:	CSIRO Livestock Industries Australian Animal Health Laboratory (AAHL) Private Bag 24 GEELONG  VIC  3213
Phone:	(03) 5227 5759
Fax:	(03) 5227 5531
Email:	john.lowenthal@li.csiro.au
bjective	·  To enhance disease resistance and vaccine efficacy in poultry by administering therapeutic doses of chicken interferon-gamma to commercial broilers and layers.
ackground	Safe, natural alternatives to antibiotics for the maintenance of optimal growth rates and flock health in chickens are being sought by the poultry industry worldwide.  Cytokines are natural proteins that are produced by the body’s immune system during infection.  Their ability to protect against disease make them excellent candidates as naturally occurring therapeutics.
Research	Previous studies on chicken interferon gamma (ChIFN-g) identified it as having therapeutic potential.  In this project, the ability of ChIFN-g to act as a growth promoter and vaccine adjuvant was assessed in trials using broiler chickens under commercial conditions.
Outcomes	An Escherichia coli expression system was developed for the large scale production of recombinant ChIFN-g protein.  The recombinant ChIFN-g was found to be biologically active.  Monoclonal antibodies were produced and an ELISA was developed for the detection of ChIFN-g.  Treatment of  broilers with ChIFN-g resulted in enhanced weight gain over a period of up to eight weeks compared to control birds. ChIFN-g treatment also reduced weight loss suffered by birds following infection with Eimeria acervulina.
Implications	Rapid transfer of this technology to the Australian poultry industry is anticipated.  These results show the feasibility of using cytokines as natural therapeutics and adjuvants.  Additional cytokines have recently been identified, including interleukins -2, -6, -15 and -18.  These are now available for a similar type of assessment. The particular activities of these new cytokines make them attractive new treatments for diseases such as coccidiosis, Marek’s disease and infectious bronchitis.
Publications	Lowenthal, J.W., O'Neil, T.E., Strom, A.D.G., and Andrew, M.E. (1999) Cytokine therapy: a natural  alternative for disease control.  Vet. Immunol. Immunopathol. 72, 183-188.
	Lowenthal, J.W., Lambrecht, B, van den Berg, T.P., Andrew, M.E., Strom, A.D.G., and Bean, A.G.D. (2000) Avian cytokines – the natural approach to therapeutics. Dev. Comp. Immunol. 24, 355-365. Lowenthal, J.W. (2001) Therapeutic applications of cytokines - what can the chicken teach us? Avian Dis. (in press). Lowenthal, J.W., Richards, G.G., Bean A.D.G., O’Neil T.E., Hilton L.S., Tyac S., Pooley, C., and Johnson M.A. (2001) New vaccination strategies for control of coccidiosis. Avian Dis. (in press). Hilton, L.S., Bean, A,G.D.,  and Lowenthal, J.W. (2001) Recent advances in avian cytokines. Vet. Immunol. Immunopatol. (Invited Review – in press). Lowenthal, J.W. et al. Chicken interferons: natural therapeutics in poultry. Avian Immunology Research Group Meeting, Turku, Finland 1998. Lowenthal, J.W. Cytokine therapy – a natural alternative for disease control. 4th Asia Pacific Health Conference, Melbourne, 1998. Lowenthal, J.W. Cytokine therapy – a natural alternative for disease control. 5th International Veterinary Immunology Symposium, India, 1998. Lowenthal, J.W.  Practical applications of chicken cytokines. 11th Australian Poultry and Feed Convention, Gold Coast. 1999. Lowenthal, J.W. et al. New strategies for enhancing immunity to Eimeria:  interferon gamma is the natural approach to disease control. Vaccines against Coccidioses conference, Dublin, 2000. Lowenthal, J.W. Therapeutic applications of cytokines - what can the chicken teach us? Avian Immunology Research Meeting, Cornell University, USA, 2000. Lowenthal, J.W. et al. New vaccination strategies for control of coccidiosis.  Avian Immunology Research Meeting, Cornell University, USA, 2000. Lowenthal, J.W. et al., Cytokines are the next generation of therapeutics. AVAP Meeting, Attwood, Vic. Oct 2000.




Project Title	NDV vaccination strategies aiming to induce high HI titres in elite breeding and layer flocks
RIRDC Project No:	DAN-159J
Researcher:	Dr George Arzey
Organisation:	NSW Department of Agriculture Elizabeth Macarthur Agricultural Institute (EMAI) PMB 8 CAMDEN  NSW  2570
Phone:	(02) 4640 6333
Fax:	(02) 4640 6300
Email:	george.arzey@agric.nsw.gov.au
Objective	·         To identify strategies capable of producing the highest and most persistent mean HI titres in vaccinated flocks.
Background	The recent availability of inactivated ND vaccines in Australia has broadened the scope for effective long-term protection of birds against Newcastle disease.  However, no sound data was previously available on the HI titres elicited when V4 was used as the priming vaccine. The present study was undertaken in order to assess a range of vaccination strategies in caged layers with the use of V4 as the priming agent
Research	Ten different vaccination strategies were evaluated by monitoring the NDV HI response over a period of 28 weeks in serologically negative 18 weeks old pullets housed in commercial cages.
Outcomes	Any of the combinations of live V4 plus inactivated vaccine trialled should protect a flock against clinical Newcastle disease. For protection against a drop in egg production, the strategies in which V4 was followed by inactivated vaccine four weeks later can be considered protective up to 24 weeks post initial vaccination.  Protection against infection for up to three months (as determined by reduced shedding of a virulent virus) can be expected with V4 delivered orally followed with inactivated vaccine four weeks later.  The studies also confirmed the poor ability of V4 to spread in flocks.
Implications	The study demonstrated that V4 used as a priming vaccine with a selective combination of an inactivated vaccine can produce high and persistent NDV HI titres that are comparable to those elicited by other live overseas vaccines in combination with inactivated vaccines.




Project Title	Investigations into the management of the darkling beetle, Alphitobius diaperinus (Panzer)
RIRDC Project No:	DAQ-244J
Researchers:	Mr Trevor Lambkin and Mr MC Cameron
Organisation:	Department of Primary Industries (Qld) Farming Systems Institute 80 Meiers Rd INDOOROOPILLY  QLD  4068
Phone:	(07) 3896 9434
Fax:	(07) 3896 9446
Email:	lambkit@dpi.qld.gov.au, camerom@dpi.qld.gov.au
Objectives	·   To review the relevant literature pertaining to A. diaperinus research and thereby develop an improved understanding of the ecology of the pest. ·   To develop an insecticide resistance testing method for A. diaperinus and subsequently survey and test broiler shed and egg barn pest populations in south east Queensland for insecticide resistance.
Background	The darkling beetle, Alphitobius diaperinus (Panzer) is a common cosmopolitan insect pest of poultry houses, in particular broiler sheds and egg barns, and is capable of transmitting a large number of poultry diseases and parasites.  In recent concern has been expressed about increasing beetle numbers in broiler sheds and the pest’s potential to breach farm bio-security.  In spite of the occurrence of the pest on almost every Australian poultry farm, no previous Australian research has been undertaken to determine the pest’s behaviour and its insecticide resistance status.  Research commenced in 1998 to address these gaps in our understanding of the pest; in particular, to develop a better understanding of the ecology of the pest and to determine if resistance to fenitrothion (Folithion®) and cyfluthrin (Tugon®) has occurred in pest populations.
Research	A review of scientific literature on darkling beetle research was undertaken to provide improved knowledge of the pest’s ecology, published research results and possible control strategies.  Work was undertaken towards the development of an effective and efficient laboratory culture method for A. diaperinus, in order to provide a constant and adequate supply of beetles for laboratory research and testing with insecticides.  A laboratory insecticide-resistance testing method was developed to provide the tools necessary to identify and characterise any insecticide resistance in A. diaperinus populations.  A survey was undertaken of local broiler shed and egg barn beetle populations and these populations were subsequently tested with fenitrothion (and some with cyfluthrin).  Each population tested was compared to a susceptible reference population and from this comparison a level of resistance was determined.
Outcomes	The scientific literature review and project field studies have indicated that the pest’s ability to avoid contact with insecticides contributes to A. diaperinus control failures.  This behaviour, together with predominantly clay-floored sheds in most broiler sheds contributes to problems with control after clean-outs, as many individuals stay concealed in the floor and do not receive a lethal dose of insecticide.  The development of a laboratory culture method has provided adequate numbers of some test insects.  Problems with the culture method arose during the latter part of the project due to mite infestations, and these have hindered the availability of insects for testing.  The development of fenitrothion and cyfluthrin resistance testing methods has been successful.  Test results have shown that insects from south east Queensland broiler systems have strong fenitrothion resistance and some cyfluthrin resistance, and preliminary results indicate that populations of A. diaperinus from some production areas, for example Armidale and the Atherton Tablelands, have quite weak fenitrothion resistance.  Insecticide resistance levels in insects from other intensive livestock systems, including egg barns are generally weaker, and all levels of resistance are directly related to duration and frequency of insecticide use.
Implications	Insecticide resistance is not the major factor that determines beetle population sizes in broiler sheds.  There is no relationship between anecdotal estimates of broiler beetle numbers and fenitrothion and cyfluthrin resistance levels, ie- population sizes of insects in different broiler sheds, with similar levels of insecticide resistance, can be very different.  Results of testing A. diaperinus from the only south east Queensland egg barn studied show that the insects are still susceptible to fenitrothion and a rotation of fenitrothion and cyfluthrin may be done on alternate clean outs.  Whether these egg barn results are typical for all is not known. For broiler sheds in general it is suggested that the application of cyfluthrin may be reduced to every second clean out (part or full) or just used over the summer period.  This may delay the development of stronger resistance.  Preliminary results for the broiler production areas of Armidale and the Atherton Tablelands indicate that fenitrothion may be included with cyfluthrin in an insecticide rotation. In summary, as development of strong insecticide resistance in all areas is inevitable given time, a closer examination is needed of the other major factors that control population sizes in broiler sheds.  When this is known, studies of currently registered insecticides, alternative control strategies and the interaction of both can be properly evaluated.
Publications	Lambkin, T.A. (1998) Controlling black beetles (Alphitobius diaperinus) in chicken sheds.  Proceedings 1998 Poultry Exchange Surfers Paradise 19-21 April 1998, 33-37. Lambkin, T.A. and Cameron, M.C. (1999) Darkling beetle control-current difficulties and future prospects. Proceedings 11th Australian Poultry & Feed Convention 10-13 October 2000,184-192. Lambkin, T.A. & Cameron, M.C. (2000) Darkling beetle control in Australian broilers - a new direction. Proceedings 2000 Poultry Exchange Surfers Paradise 9-11 April 2000, 97-102.




Project Title	The development of effective immunisation strategies against Marek’s disease
RIRDC Project No:	RMI-6J
Researcher:	Prof Greg Tannock
Organisation:	RMIT University Virology Laboratory PO Box 71 BUNDOORA  VIC  3083
Phone:	(03) 9925 7142
Fax:	(03) 9925 7110
Email:	gtan@rmit.edu.au
Objectives	·   To improve the performance of existing Marek’s disease vaccines using suitable adjuvants. ·   To characterise MDV strains after adaptation to continuous cell lines. ·    To develop a MDV serotype 1 specific probe to use in a dot-blot hybridisation technique.
Background	For almost 30 years, Marek’s disease (MD) has been largely controlled by the use of intensive vaccination with herpesvirus of turkeys (HVT), either alone or in combination.  However, in recent years HVT vaccines have shown to be much less effective against emerging field strains of MDV of increasing virulence. Adjuvants are used to improve the immunogenicity of a vaccine without increasing the amount of infectious virus in the vaccine.  An adjuvant enhancing the performance of the HVT vaccine would be a value-added benefit to a cheap and readily available existing vaccine. The adaptation of MDVs to growth in a continuous cell line could be useful for vaccine production, compared with the labour and reagent  intensive CEF cultures that are currently used.  Because of limitations associated with current detection techniques for MDV serotype 1 virus, a MDV1 specific probe used in a rapid identification assay which is less expensive and more specific than those currently available, would be very useful for field diagnosis and important in vaccine evaluation.
Research	Commercial broiler chickens were used to assess the possible role of g-inulin as an adjuvant to improve the efficiency of HVT vaccination against MD.  Chickens were administered vaccine with or without g-inulin using three vaccination procedures: (i) in-ovo, by InovojectÒ, (ii) in ovo by hand, or (iii) subcutaneously (sc) at day old.  All birds were challenged with a virulent MDV 1 challenge virus at three days of age. Effective vaccination by HVT was assessed by the development of viraemia. HVT and MDV1 were adapted to the Vero continuous cell line (Jaikumar, 2001) and were characterised by immunological and molecular techniques. A probe labelled with digoxigenin (DIG) was developed for the detection of MDV 1 by dot-blot hybridisation.  The probe was labelled  by the incorporation of DIG in a PCR reaction product that consisted of the amplified 132 bp repeat located within the inverted repeat long region of the MDV 1 genome. The sensitivity and specificity of virus isolation and dot-blot hybridisation were compared with PCR, which was used as the reference procedure.
Outcomes	In the vaccination trial, MD was present in all treatment groups but its incidence in groups treated with g-inulin was not significantly different from non-treated groups.  Differences in the percentages of MD in groups administered g-inulin using the InovojectÒ method or sc at day 1 were also non-significant.  No adverse effects due to g-inulin were noted in any group. HVT grew more rapidly and produced more extensive CPE and higher virus yields in Vero cell lines than MDV1. When the genome of adapted serotype 1 viruses was examined, an expansion of the 132 bp DR sequence indicated that the infected cell line contained serotype 1 MDV DNA.  The presence of intact DNA with a size of approximately 180 kb in both serotype 1- and HVT-infected Vero cells after isolation and characterisation indicated that whole copies of both types of DNA were present and provided further evidence for adaptation to growth of the serotype 1 virus.  This is the first report of the growth of either virus in a continuous line. Highest sensitivity rates were achieved by dot-blot hybridisation using the 132 bp PCR probe, compared with virus isolation and identification by immunoperoxidase or immunofluorescence.  Despite their much lower sensitivity, higher specificity was obtained by both culture detection methods than for the dot-blot hybridization
Implications	This project has shown that g-inulin did not appear to function as an adjuvant when administered with HVT vaccine.  The presence of intact DNA with a size of approximately 180 kb in both serotype 1- and HVT-infected Vero cells after isolation and subsequent analysis in a pulsed-field gel indicates that whole copies of both types of DNA were present and provides further support for adaptation to growth of the serotype 1 virus, thus would be useful for new and improved vaccine production procedures. The dot-blot hybridisation technique using the DIG-labelled probe specific for MDV 1 was shown to be potentially very useful as a rapid and economical test to detect MDV.
Publications	Cipriani, T. L. (2000) The development of two digoxigenin-labelled probes for the detection of Marek’s disease virus by dot-blot hybridisation. B. App.Sc.Honours Thesis. Jaikumar, D. (1998) Propagation and molecular characterisation of Marek’s disease virus. Master of App.Sc. Thesis. Jaikumar, D. (2001) Adaptation of Marek’s disease virus to the Vero continuous cell line. Veterinary Microbiology 70, 75-82.




Project Title	Characterisation of very virulent Australian isolates of Marek’s disease virus
RIRDC Project No:	RMI-8J
Researcher:	Prof Greg Tannock
Organisation:	RMIT University Virology Laboratory PO Box 71 BUNDOORA  VIC 3083
Phone:	(03) 9925 7142
Fax:	(03) 9925 7110
Email:	gtan@rmit.edu.au
Objectives	·   To collect and maintain a repository of serotype 1 strains of Marek’s disease virus (MDV) representative of Australia and to characterise them for future reference. ·   To determine optimum methods for standardising Marek’s disease (MD) vaccines. ·    To prepare and maintain reference preparations of NDV for use in vaccine assays. ·    To provide an independent, reliable vaccine assay facility for use by Australian vaccine manufacturers in harmony with requirements set by NATA. ·    To continually maintain and supply MDV challenge preparations for use by the industry.
Background	MD is currently a significant economic problem for the Australian chicken industry.  Current, locally developed vaccines appear to provide very little protection against recently isolated very virulent strains of MDV.  The availability of new vaccines increases the need for a reliable assay system to evaluate their effectiveness.  Previously, vaccine assays were carried out by individual manufacturers without access to standard reference preparations.  A repository will allow study trends in the evolution of MDV to be studied.
Research	Blood samples were collected from flocks in different parts of the country that have been experiencing MD losses.  These samples were screened for the presence of serotype 1 MDV.  Positive samples were stored in liquid nitrogen for future reference. In consultation with vaccine manufacturers and industry representatives, the Virology Laboratory set up a vaccine assay facility and is seeking accreditation with the National Association of Testing Authorities (NATA).  During the establishment phase of the assay, a nominal cell count and virus titre, with maximum and minimum limits, were set for two reference preparations and were revised after their substantial use to monitor the stability of the assay. Studies were carried out in response to industry concerns about possible losses to vaccine potency from the widely used practice of using chilled diluent whilst administering vaccines.  Another study assessed the differences between operators whilst performing vaccine assays.
Outcomes	Some 300 blood samples were collected, of which 86 were positive for serotype 1 MDV.  Characterisation studies did not commence within the project’s time frame.  However, despite their pre-characterisation status, the samples remain as a viable repository of MDV isolates and will be available for comparative purposes in the future. A liquid overlay procedure was adopted for the vaccine assay and over 1000 assays have been conducted since the establishment of the facility in January 1998.  Few manufacturers have used the facility despite its availability to all Australian manufacturers.  An impending move to a new purpose-built facility and its audit, will take place before registration with NATA. The revised cell count and virus titre results indicated the stability of each reference preparation and thus validated the nominal virus titres used throughout the assay procedure.  The use of diluent held at room temperature substantially decreases virus titre loss (as opposed to holding diluent at 4°C).  Therefore, it is critical to maintain diluent at room temperature whilst administrating MD vaccines to maintain their potency.  Differences in vaccine titre of parallel assays of two operators were non significant and, consequently, did not affect the assay result.
Publications	Two presentations on the functions of the vaccine assay facility were given at meetings of the Australian Veterinary Poultry Association at Surfers’ Paradise in April 1999 and the Victorian Poultry Health and Welfare Liaison Group in September 1999.

Project Title	Development of a live attenuated vaccine for chicken anaemia virus
RIRDC Project No:	UM-37A
Researcher:	Dr Glenn Browning
Organisation:	The University of Melbourne Veterinary Preclinical Centre PARKVILLE  VIC  3052
Phone:	(03) 8344 7342
Fax:	(03) 8344 7374
Email:	glenfb@unimelb.edu.au
Objective	·   To improve control of CAV related disease in chickens by:      Performing directed mutagenesis on the genome of chicken anaemia virus (CAV) to develop attenuated mutants       Assessment of attenuated mutants of CAV as live vaccines for administration to breeder flocks, broilers and pullets       Assessment of the suitability of DNA vaccination with these attenuated mutants.
Background	The role of chicken anaemia virus (CAV) in immunosuppressive diseases has become more evident in recent years.  It contributes not only to severe immunosuppression in progeny from recently exposed parents, but also to high mortality from Marek’s disease virus associated with donor progeny susceptible to CAV, both in Australia and overseas.  Increasing attention is now being paid to declining immunity in donor flock dams, which result in variable to poor progeny performance. Control of disease due to CAV currently relies predominantly on controlled exposure of breeder birds to virulent virus.  This strategy will not control subclinical disease that results from exposure of older birds with waning immunity, leading to an increased risk of vertical transmission.  Furthermore, this method has the problem of perpetuating the presence of virulent CAV in the environment. The need for a safe immunogenic, universally available attenuated CAV vaccine is clearly evident.
Research	In order to develop an attenuated vaccine suitable for administration to all birds we have produced an infectious clone of the genome of an Australian isolate of CAV and have been introducing mutations into specific regions of the gene for VP2, one of the three viral proteins.  The regions targeted are predicted to play a role in the function of VP2 during viral infection.
Outcomes	Thus far we have produced a series of mutant viruses and have assessed the degree of attenuation in chick embryos.  All mutants were significantly attenuated in their capacity to cause lesions in the thymus, spleen and bursa of embryos.  Further studies (RIRDC Project UM-55A) are now examining the extent of attenuation in day old chicks and the protection afforded by vaccination with these mutants. The full technical report for this project is commercial-in-confidence and is not available for general publication.
Implications	The feasibility of using site specific mutagenesis to produce attenuated strains of CAV has been demonstrated.  Furthermore, some vaccine candidates have been produced.  Further work is needed to assess the extent of attenuation achieved, and additional mutagenesis may be needed to produce a strain that is suitable for use as a vaccine.  Work still needs to be done to assess the protective immunity induced by these strains, and further work is needed to assess the potential of DNA vaccination.
Publications	Brown, H. K., Browning, G. F., Scott, P. C. and Crabb, B. S. (2000) Full-length infectious clone of a pathogenic Australian isolate of chicken anaemia virus. Aust. Vet. J., 78:637-640

Project Title	Postgraduate scholarship – David Witcombe: Production and characterisation of recombinant antigens of Eimeria
RIRDC Project No:	UTS-3J
Researcher:	Mr David Witcombe and Nicholas Smith
Organisation:	University of Technology Molecular Parasitology Unit Dept of Cell and Molecular Biology PO Box 123 BROADWAY  NSW  2007
Phone:	(02) 9514 4013
Fax:	(02) 9514 4026
Email :	Nick.Smith@uts.edu.au
Objectives	·    To prepare recombinant versions of a putative subunit vaccine candidate from Eimeria, the 230 kDa merozoite protein. ·    To explore the potential molecular relationships between this protein and gametocyte proteins of Eimeria. ·     To determine the importance of glycosylation of these proteins for induction of immunity. ·     To determine how the genes encoding these antigens are organised and expressed in the genome and whether they undergo antigenic variation or diversification. ·     To assess whether combination immunoprophylaxis (eg vaccination with merozoite and gametocyte antigens) is more efficacious than vaccination with antigens from one developmental stage alone.
Background	Coccidiosis, caused by the protozoan parasite, Eimeria, is a major pathogenic disease of poultry worldwide.  Coccidiosis costs the poultry industry internationally over $1 billion per year. The resistance of the parasite to anticoccidials, the high cost of development of new anticoccidials and the demands by the public for chemical-free meat drive the quest for a vaccine to control coccidiosis.  Young chickens are protected against Eimeria by the transfer of antibodies from their mothers into the egg yolk, which is absorbed by hatchlings.  These maternal antibodies have been used to identify proteins for inclusion in a vaccine.  Exploration into the molecular composition of these proteins of Eimeria will allow deduction of the minimal components required for an effective vaccine.  The development of a maternally-delivered vaccine against coccidiosis will benefit the poultry industry by allowing reduced use of chemotherapy, potentially effecting a significant cost reduction and satisfying consumer demand for residue-free meat.
Research	The 230 kDa merozoite antigen of Eimeria maxima has been purified and N-terminal and internal tryptic digest amino-acid sequences determined.  Using these sequences, the genetic code for the protein has been determined.  Expression and production of recombinant proteins are underway. The sequences of gametocyte antigens (amino acid and genetic sequences) do not appear to be related to the sequence of the 230kDa protein. There are several potential glycosylation sites in the 230 kDa merozoite protein. Similar sequences appear to be found in several species of Eimeria. Immunogenicity and efficacy trials using purified native and recombinant versions of the 230 kDa E. maxima merozoite protein will commence shortly.
Implications	The results obtained to date suggest that the 230 kDa protein of E. maxima is a stage-specific molecule (found in asexual stages only).  However, the observation that this protein is present in more than one species of Eimeria suggests that it has some conserved and important function in the development of the parasite.  Therefore, it is a logical target for use in a subunit vaccine against coccidiosis.
Publications	Witcombe, D., Belli, S., Wallach, M. and Smith, N. (2000) Western blot analyses and purification of an immunodominant asexual stage protein from Eimeria maxima. New Zealand and Australian Societies for Parasitology, Annual Scientific and General Meeting, Wellington, September. Belli, S., Witcombe, D., Padula, M., Wallach, M. and Smith, N. (1999) The use of SDS-PAGE and 2-D PAGE in the analysis of parasite derived antigens.  Australian Electrophoresis Society Sixth Annual Conference, Melbourne, October. Witcombe, D., Belli, S., Wallach, M. and Smith, N. (1999) Characterisation of an immunodominant merozoite antigen from Eimeria maxima.  Vaccines Against Animal Coccidioses, Interlaken, Switzerland, November.


Feed Availability and Nutrition
 

Project Title:	Alternative protein sources for laying hens
RIRDC Project No:	DAQ-241A
Researcher:	David Robinson
Organisation:	Dept of Primary Industries (Qld) The Queensland Poultry Research and Development Centre PO Box 327 CLEVELAND  QLD  4163
Phone:	(07) 3824 3081
Fax:	(07) 3824 4316
Email:	robinsd0@dpi.qld.gov.au
Objective	·     To broaden the base of locally available vegetable protein sources that can be profitably included in the diet of layers.  A literature review of alternative protein sources was first conducted, with special reference to grain legumes and suitability for conditions in northern Australia.  Suitable recently introduced cultivars of grain legumes were identified and evaluated in laying hen trials.  The nutritional profiles of these legumes were established and levels of common ANFs in the legumes were determined.  Implications for the industry were discussed and recommendations with regard to further development and usage were then made, including safe maximum concentrations of the legumes in layer diets.
Background	Traditional ingredients in poultry diets are forecast to be in short supply within ten years.  Inevitably there will be an increase in the world-wide demand for protein feed which is expected to be met largely by legumes and canola.  As total feedgrain production in Australia is forecast to decline over the medium term, there is a risk of becoming more reliant on imports.  While grain legume production in Australia is increasing, most of this harvest is grown in the southern states, primarily for human consumption.  It would be highly advantageous to shift some of this production northwards, both to meet the demands of the livestock industry in this region more economically and to provide more agronomic diversity in the region.  Some legume varieties are well suited to subtropical regions and show promise as competitive sources of protein for livestock.  Agronomists recognise that increased cultivation of grain legumes would make a valuable contribution to sustainable agriculture.
Developments	A review of alternative protein sources for layers, with special consideration for grain legumes, was completed and accompanies this report.  Three varieties of chickpea, two of mung bean, two of cowpea and one of lablab were selected for evaluation for laying hens, and batches of Queensland-grown grain of each variety were obtained.  Nutrient analyses, metabolisable energy determinations and measurements of a range of ANFs were completed for all these materials.  Three successive rounds of laying hen performance trials (each of approximately four months duration) were conducted, using IsaBrown layers.  In each trial, several cultivars were included in nutritionally balanced layer diets at a range of concentrations determined on the basis of the laboratory information and existing knowledge of layer (or broiler) responses to the species of legume being tested.  All cultivars were studied in untreated form using mash diets, but the effects of steam pelleting and decortication were also investigated with selected cultivars.
Outcomes	Varieties of the same legume species were nutritionally similar, except that total sulphur amino acid levels were much lower in Amethyst chickpea than in Barwon or Dooen.  Trypsin inhibitor activity  was higher in chickpea and lablab  than in mung bean, and higher in Amethyst than in Barwon chickpea.  However, bird performance appeared to be unrelated to ANF levels, which therefore did not provide a useful indicator of safe maximum concentrations of legume in the diet.  Diet composition (legume type and level) did not significantly affect mortality, and reduced mean egg weight in only one case (400 g/kg lablab).  In trial 1, diets containing 450 g/kg Delta or Emerald mung bean or 300 g/kg Barwon chickpea resulted in 7-9% fewer eggs, 4-5 g/d lower egg mass and 9-10% poorer feed conversion than the control diet.  Bodyweight gain over the trial period was depressed by 90-150 g in four of the six chickpea treatments.  Trends in the data suggested that both Amethyst and Barwon chickpea had a depressing effect on egg mass output when included in the diet at concentrations above 100 g/kg.  In trial 2, Koala lablab at 400 g/kg in mash or pelleted diets resulted in markedly lower egg number, egg mass output and feed intake and poorer feed conversion than any other treatment but did not affect body weight gain.  In this trial none of the chickpea (Amethyst) or mung bean (Emerald) treatments differed significantly from the mash or pellet control treatment in respect of egg number, feed intake or feed conversion.  However, birds given 450 g/kg mung bean as mash produced less egg mass but gained more bodyweight than the control birds.  Egg weight was 0.87 g higher when birds were fed pelleted instead of mash diets.  Mung bean at 450 g/kg in the pelleted diet resulted in 14% more eggs than the control pellets.  Although there were no interactions between diet form and diet composition, diets containing 200 or 300 g/kg chickpea tended to depress performance when fed as mash but not when fed as pellets.  In trial 3, moderate levels of Caloona or Red Caloona cowpea (125-250 g/kg) or Dooen chickpea (175 g/kg) tended to increase egg number and egg mass output compared to the control diet or diets containing high levels (350-375 g/kg) of these legumes.  Decortication of Dooen chick pea tended to adversely affect egg mass output.  Body weight gain consistently declined (or body weight loss increased) with increasing dietary levels of legumes.  The average yolk colour score of eggs from birds given 375 g/kg Red Caloona cowpea was substantially higher (P<0.001) than that of the control treatment. The results overall suggest that safe dietary concentrations for long term feeding of untreated grain legumes in mash diets for laying hens are (g/kg): Barwon and Amethyst chickpea 100, Dooen chickpea 175, mung bean 300, lablab <100, Caloona cowpea 150, Red Caloona 100.  These levels may be increased for short term feeding or if the diet is steam pelleted.
Implications	By providing information on nutrient composition, ANF levels and safe maximum dietary concentrations for a range of grain legume varieties, this research will primarily benefit stockfeed manufacturers.  Mung beans were of greatest value, followed by cowpeas and chickpeas.  Benefits to the egg industry will flow through mainly from the lower cost diets that will ensue from the wider variety of feed ingredients and higher usage levels of these ingredients.  The performance results provided some suggestion that inclusion of certain grain legumes at low to moderate concentrations in layer diets may improve production.  ANF profiles did not provide a reliable guide to maximum inclusion rates.  This research plays an important part in the promotion of locally grown products as substitutes for imported protein meals.  The grain legumes studied in this project also show potential for export growth, while at the same time they will command strong interest by the livestock feed sector.  Increased knowledge of the particular limitations of different species and cultivars in poultry nutrition should encourage plant breeders to apply appropriate selection pressures to further improve the varieties suited to poultry.  Grain growers should be aware that Koala lablab appears to be less suitable for poultry feeding than the other grain legumes investigated in this project. The greatest impact of this project on the Australian economy is probably its influence on the reduction of imports, expansion of exports, development of local agriculture and the long-term sustainability of the grain industry.  To achieve these benefits to the fullest extent it is important to do research within the poultry sector, but the direct benefits to that sector, though significant, may turn out to be comparatively small.
Publications	Robinson, D. and Datugan, M.J. (1999) Untreated chick pea and mung bean in layer diets.  Queensland Poultry Science Symposium 8, pp 14-1 – 14-5. Robinson, D., Datugan, M.J., Singh, D.N. and Barram, K.M. (2000) Evaluation of untreated grain legume varieties for laying hens.  Australian Poultry Science Symposium12: 205.

Project Title	Premium Grains for Livestock Program
RIRDC Project No:	GRD-1J
Researcher:	Dr John Black
Organisation:	John L Black Consulting Locked Bag 21 WARRIMOO  NSW  2774
Phone:	(02) 4753 6231
Fax:	(02) 4753 6295
Email:	jblack@pnc.com.au
Objectives	·    To identify the reasons for and magnitude of differences between grains in their nutritional value for ruminants, pigs and poultry so that improvements in grain quality can be achieved by plant breeding and through grain processing and storage. ·     To develop rapid tests, suitable for the site of grain receipt and/or use, to measure the nutritional value of grains so that they can be priced in accordance with their suitability as an animal feed. ·     To develop a computer simulation model for ruminants to predict accurately the consequences of grain characteristics and of grain processing and storage on the productivity of feedlot cattle.
Background	The Program involved collaborative funding from the Grains, Pig and Dairy R&D Corporations, Meat and Livestock Australia and the Chicken Meat and Egg Programs of RIRDC. The Program is expected to improve the quality of grains available to the animal industries and to provide a more rational basis for trading feed grains based on measurement of the nutritional characteristics of grains determining their quality for different livestock enterprises.
Research	Over 2000 grain samples covering the widest possible range in chemical and physical characteristics that may influence animal performance have been collected.  The samples have been derived from germplasm collections, plant breeders, specially grown crops and commercial grains suspected of having extremes in nutritional values because of severe drought, frost damage or germination.  All samples collected have been scanned with near infrared spectrometry (NIR).  Approximately 115 analyses of chemical and physical characteristics thought to influence nutritional value have been conducted on all grains fed to animals.  These involved analyses for individual carbohydrate, fatty acid and amino acid components, a- and b-amylase and anti-nutritional factors such as lectins, tannins and phytic acid.  Physical properties included measurement of grain weight, hydration capacity, seed colour, seed diameter, seed size distribution, seed hardness index and profile, and the viscosity of whole grain, starch extract and acid soluble extract.  Light and electron microscopy has been used to examine the physical structure of some grains that differ markedly in their nutritional value. Many grains, including all those fed to animals have been examined using in vitro systems simulating both rumen fermentation and intestinal digestion. These analyses have been extremely useful for identifying grains that potentially have large differences in nutritional value for different classes of livestock and for screening potential processing procedures.  A relatively small number of grains (approximately 100) covering the range identified in chemical and physical characteristics have been fed to sheep, cattle, pigs, broiler chickens and laying hens to determine the digestion of energy, individual grain compounds and, in some animal species, amino acids.  The effects of processing and storage on the nutritional value of grain for different animal species have been evaluated using the in vitro systems.  Development of rapid and accurate analytical tests for measuring the most important chemical and physical characteristics that determine nutritional value of feed grains has commenced.  Preliminary analyses using NIR have been developed for predicting the digestible energy content of grains for pigs, apparent metabolisable energy (AME) for broiler chickens and whole animal dry-matter digestibility for sheep.  In addition, NIR procedures have been used for predicting the major chemical components of grains and for predicting the in vitro digestion of various grain components.
Outcomes	Results show that there is a wide variation in energy availability both within and between cereal grain species and between animal types.  For example, the observed range in AME (MJ/kg) for broiler chickens for the grains examined in the Program is 15.4-16.1 for sorghum, 13.2-14.7 for wheat, 11.2-13.2 for barley, 11.2-14.4 for triticale, 12.6-13.4 for normal oat grain and 14.6 for naked oats.  Naked oats had an AME value of 16.2 for laying hens.  Sorghum has a much lower available energy content for cattle at 9.7 MJ/kg than for pigs (14.6 MJ/kg) or broiler chickens (15.9 MJ/kg).  The energy value of waxy sorghum is enhanced considerable for cattle to 13.2 MJ/kg, but there was only a marginal increase of 0.1 to 0.5 MJ/kg for pigs and poultry.
Implications	Several hypotheses about the factors determining the nutritional value of cereal grains for different animal types have been established and are being evaluated in the current Project GRD-3J.
Publications	Balogun, R., Bird, S. H. and Rowe, J. B. (2000) Improving the nutritive value of sorghum grain by germination.  Asian-Australian Journal of Animal Science. 13 (supp): 160. Bird, S. H., Rowe, J. B., Choct, M., Stachiw, S., Tyler, P. and Thompson, R. D. (1999) In vitro fermentation of grain and enzymatic digestion of starch.  Recent Advances in Animal Nutrition in Australia (Editor J. L. Corbett), 12: 53-61. Black, J. L. (1999) Nutritional value of cereal grains for animals.  Chemistry in Australia. 66: 7-9. Black, J. L. (1999) The Premium Grains for Livestock Program.  In: The Eleventh Australian Poultry & Feed Convention, Royal Pines Resort Gold Coast, Australia. pp. 226-32. Black, J. L.  (2001) Variation in nutritional value of cereal grains across livestock species. Australian Poultry Science Symposium, University of Sydney, Sydney, Australia 13: 22-9. Choct, M., Hughes, R. J., Perez-Maldonado, R. and van Barneveld, R. J. (2001) The metabolisable energy value of sorghum and barley for broilers and layers. Australian Poultry Science Symposium, University of Sydney, Sydney, Australia 13: 39-42. Dixon, R. M. and Stockdale, C. R. (1999) Associative effects between grains and forages: consequences for feed utilisation.  Australian Journal of Agricultural Research50: 757-73.
	Evers, A. D., Blakeney, A. B. and O’Brien, L. (1999) Cereal structure and composition. Australian Journal of Agricultural Research. 50: 629-50. Farrell. D. J.  (1999) In vivo and in vitro techniques for the assessment of the energy content of feed grains for poultry: a review.  Australian Journal of Agricultural Research 50: 881-8. Flinn, P. C.  (2000) Current and potential use of NIR in the fodder and grain industries: a ruminant’s perspective.  In: Reading more from the spectrum, 9th Australian Near Infrared Spectroscopy Conference, Horsham, VIC, Apr 2000. Flinn, P. C.  (2000) Rapid methods for the quality assessment of grains for animal nutrition.  In: Chemical aspects of grain in human and animal nutrition., Cereal Chemistry Division Symposium, 11th RACI Convention, Canberra, ACT, Feb 2000, p15. Flinn, P. C., Heazlewood, P. G. and Dalton, S. L.  (2000) Recent developments in improving the prediction of digestibility of feed grains.  In:  9th International Conference on Near Infrared Spectroscopy Verona, Italy, Jun 1999 (in press). Hogan, J. P. and Flinn, P. C. (1999) An assessment by in vivo methods of grain quality for ruminants.  Australian Journal of Agricultural Research 50: 843-54. Hughes, R. J. and Choct, M. (1999) Chemical and physical characteristics of grains related to variability in energy and amino acid availability in poultry.  Australian Journal of Agricultural Research 50: 689-701.  Hughes, R. J., Choct, M. and van Barneveld, R. J. (2001) Factors influencing the energy values of Australian cereal grains fed to broilers.  Australian Poultry Science Symposium, University of Sydney, Sydney, Australia 13: 30-8. Kaiser, A. G. (1999) Increasing the utilisation of grain when fed whole to ruminants.  Australian Journal of Agricultural Research. 50: 737-56. Kitessa, S., Flinn, P. C. and Irish, G. G. (1999) Comparison of methods used to predict the in vivo digestibility of feeds in ruminants: A review. Australian Journal of Agricultural Research 50: 825-41. Kruk, J. A. and van Barneveld, R. J. (1999) Near infra-red spectrophotometry predictions of digestible energy in cereals for pigs.  In: Manipulating Pig Production VII (submitted, Editor P. D. Cranwell) Australasian Pig Science Association, Werribee, VIC. Nagorka, B. N. (2000) A ruminant model to estimate the nutritive value of grains in cattle feedlots. International Report, CSIRO CLI. Nagorka, B. N., Gordon, G. L. R. and Dynes, R. A. (2000) Towards a more accurate representation of fermentation in mathematical models of the rumen.  Modelling Nutrient Utilization in Farm Animals (Editors McNamara, J. P., France, J. and Beever, D. E.) CAB International, London (in press). Moughan, P. J. (1999) In vitro techniques for the assessment of the nutritive value of feed grains for pigs: a review.  Australian Journal of Agricultural Research 50: 871-9. O’Brien, L. (1999) Genotype and environment effects on feed grain quality