28 research outputs found
Re-use of chicken litter across broiler cycles – managing the food-borne pathogen risk
Thus the objectives of this study can be broadly categorised as follows:-
Evaluate current practices adopted (e.g. litter pile-up) prior to re-use of litter for subsequent chicken cycles
To establish pathogen die-off that occurs during currently adopted methods of in-shed treatment of litter
To establish simple physical parameters to monitor this pathogen reduction and create an understanding of such reduction strategies to aid in-shed management of re-use litter
To carry out studies to assess the potential of the re-used litter (once spread) to support pathogens during a typical chicken production cycle.
To provide background data for the development of a simple code of practice for an in-shed litter pile-up proces
Fate of key food-borne pathogens associated with intensive pig and poultry farming environments
Intensive pig and poultry farming in Australia can be a source of pathogens with implications for food-safety and/or human illness.
Seven studies were undertaken with the following objectives:
· Assess the types of zoonotic pathogens in waste
· Assess the transfer of pathogens during re-use both within the shed and externally in the environment
· The potential for movement of pathogens via aerosols
In the first and second studies the extent of zoonotic pathogens was evaluated in both piggery effluent and chicken litter and Salmonella and Campylobacter were detected in both wastes.
In the third study the dynamics of Salmonella during litter re-use was examined and results showed a trend for lower Salmonella levels and serovar diversity in re-used litter compared to new litter. Thus, re-use within the poultry farming system posed no increased risk.
The fourth study addressed the direct risks of pathogens to farm workers due to reuse of piggery effluent within the pig shed. Based on air-borne Escherichia coli (E. coli) levels, re-using effluent did not pose a risk.
In the fifth study high levels of Arcobacter spp. were detected in effluent ponds and freshly irrigated soils with potential food-safety risks during the irrigation of food-crops and pasture.
The sixth and seventh studies addressed the risks from aerosols from mechanically ventilated sheds. Staphylococci were shown to have potential as markers, with airborne levels gradually dropping and reaching background levels at 400 m distance. Salmonella was detected (at low levels) both inside and outside the shed (at 10 m). Campylobacter was detected only once inside the shed during the 3-year period (at low levels). Results showed there was minimal risk to humans living adjacent to poultry farms
This is the first comprehensive analysis studying key food-safety pathogens and potential public health risks associated with intensively farmed pigs and poultry in Australia
Food-borne pathogens and animal botulism issues surrounding the on-farm composting of layer chicken waste and mortalities – a review
Fate of key food-borne pathogens associated with intensive pig and poultry farming environments
Intensive pig and poultry farming in Australia can be a source of pathogens with implications for food-safety and/or human illness.
Seven studies were undertaken with the following objectives:
· Assess the types of zoonotic pathogens in waste
· Assess the transfer of pathogens during re-use both within the shed and externally in the environment
· The potential for movement of pathogens via aerosols
In the first and second studies the extent of zoonotic pathogens was evaluated in both piggery effluent and chicken litter and Salmonella and Campylobacter were detected in both wastes.
In the third study the dynamics of Salmonella during litter re-use was examined and results showed a trend for lower Salmonella levels and serovar diversity in re-used litter compared to new litter. Thus, re-use within the poultry farming system posed no increased risk.
The fourth study addressed the direct risks of pathogens to farm workers due to reuse of piggery effluent within the pig shed. Based on air-borne Escherichia coli (E. coli) levels, re-using effluent did not pose a risk.
In the fifth study high levels of Arcobacter spp. were detected in effluent ponds and freshly irrigated soils with potential food-safety risks during the irrigation of food-crops and pasture.
The sixth and seventh studies addressed the risks from aerosols from mechanically ventilated sheds. Staphylococci were shown to have potential as markers, with airborne levels gradually dropping and reaching background levels at 400 m distance. Salmonella was detected (at low levels) both inside and outside the shed (at 10 m). Campylobacter was detected only once inside the shed during the 3-year period (at low levels). Results showed there was minimal risk to humans living adjacent to poultry farms
This is the first comprehensive analysis studying key food-safety pathogens and potential public health risks associated with intensively farmed pigs and poultry in Australia
Re-use of chicken litter across broiler cycles – managing the food-borne pathogen risk
Thus the objectives of this study can be broadly categorised as follows:-
Evaluate current practices adopted (e.g. litter pile-up) prior to re-use of litter for subsequent chicken cycles
To establish pathogen die-off that occurs during currently adopted methods of in-shed treatment of litter
To establish simple physical parameters to monitor this pathogen reduction and create an understanding of such reduction strategies to aid in-shed management of re-use litter
To carry out studies to assess the potential of the re-used litter (once spread) to support pathogens during a typical chicken production cycle.
To provide background data for the development of a simple code of practice for an in-shed litter pile-up proces
Suitability of litter amendments for the Australian chicken meat industry
This project focused on litter amendment products, which are used overseas during the rearing of meat chickens. Litter amendments are primarily used to manage ammonia volatilisation, especially when litter is reused, but also provide antimicrobial and environmental benefits, and increase the nutrient value of spent litter.
This report summarises the outcomes of consultation with representatives and stakeholders of the Australian chicken meat industry, and summarises key findings from a literature review on litter amendments
Moving from concept to control; use of phages for Campylobacter reduction
Poultry are a major source of Campylobacter with the organism having no impact on the bird. Irrespective of this situation, the important single source of campylobacteriosis is considered to be broiler meat (European Food Safety Authority 2016). The reported number of cases of campylobacteriosis in Australia in 2015 was 22,573 (Communicable Disease Intelligence 2019). Studies have suggested that a reduction in Campylobacter levels by greater than 2-log10 units would contribute to the reduction of the public health risk by more than 90% (European Food Safety Authority 2011). Overseas models have suggested that bacteriophage treatment has the greatest potential of all known/potential methods to reduce Campylobacter levels in the live chicken (Havelaar et al. 2007).
Campylobacter naturally colonises the chicken gut, where it can reach high numbers and potentially contaminate the marketed product. A low number of organisms can cause human illness. This study is exploring a biocontrol option using bacteriophages (phages) to reduce Campylobacter numbers in chickens. Bacteriophages are viruses that infect and kill the target bacteria. These specific, Campylobacter-killing phages occur naturally in farm chickens, where they are already in a ‘predator–prey relationship’ with Campylobacter. The aim of this study is to better the outcome of this natural phenomenon. The study builds upon data from previous studies to progress the option of using Campylobacter bacteriophages to control Campylobacter levels in poultry.
The report is targeted at the Australian Poultry Industry, those with a role of food-safety at an industry level and also have a regulatory role
Investigation and application of methods for enumerating heterotrophs and Escherichia coli in the air within piggery sheds
Aims: To investigate methods for the recovery of airborne bacteria within pig sheds and to then use the appropriate methods to determine the levels of heterotrophs and Escherichia coli in the air within sheds.
Methods and Results: AGI-30 impingers and a six-stage Andersen multi-stage sampler (AMS) were used for the collection of aerosols. Betaine and catalase were added to impinger collection fluid and the agar plates used in the AMS. Suitable media for enumerating E. coli with the Andersen sampler were also evaluated. The addition of betaine and catalase gave no marked increase in the recovery of heterotrophs or E. coli. No marked differences were found in the media used for enumeration of E. coli. The levels of heterotrophs and E. coli in three piggeries, during normal pig activities, were 2Æ2 · 105 and 21 CFU m)3 respectively.
Conclusions: The failure of the additives to improve the recovery of either heterotrophs or E. coli suggests that these organisms are not stressed in the piggery environment. The levels of heterotrophs in the air inside the three Queensland piggeries investigated are consistent with those previously reported in other studies. Flushing with ponded effluent had no marked or consistent effect on the heterotroph or E. coli levels.
Significance and Impact of the Study: Our work suggests that levels of airborne heterotrophs and E. coli inside pig sheds have no strong link with effluent flushing. It would seem unlikely that any single management activity within a pig shed has a dominant influence on levels of airborne heterotrophs and E. col
Impact of the Australian litter re-use practice on Salmonella in the broiler farming environment
This study has examined the dynamics (in terms of levels and serovar diversity) of Salmonella in the "dual litter environment" that occurs within a single shed as a result of a management practice common in Australia. The study also looked at the physical parameters of the litter (pH, moisture content, water activity and litter temperature) as a means of understanding the Salmonella dynamics in these litter environments. The Australian practice results in the brooder end of the shed having new litter each cycle while the grow-out end has re-used litter (a "dual litter environment"). Two farms that adopted this partial litter re-use practice were studied over one full broiler cycle each. Litter was sampled weekly for the levels (and serovars) of Salmonella during a farming cycle. There was a trend for lower levels of Salmonella (and a lower Salmonella serovar) diversity in the re-used litter environment as compared with the new litter environment. Of the physical parameters examined, it would appear that the lower water activity associated with the re-used litter may contribute to the Salmonella dynamics in the dual environment