21/02/2023
Marie Somville y Frédéric Pradelle, from Octopus Robots, was in charge of the presentation on “Contamination vectors and sanitary challenges in poultry farming” during the LPN Congress 2018.
Treatment and work of the litter
Today poultry farming must face several problems; between intense production, animal welfare, pathogens, and the environment, the pressures on poultry farming are multiple. Control of the internal conditions of the buildings is essential to obtain sufficient production in an environment conducive to animal welfare.
Causes and problems derived from litter
The problem regarding health risks and animal welfare is fundamentally a microbiological problem directly related to poultry litter. It is healthy at the start of the flock, but it gradually becomes laden with poultry droppings, food scraps, and water.
Excessive humidity causes the accumulation of litter, the development of bacteria and other microorganisms, and a more significant release of ammonia. The formation of ammonia is caused by the fermentation of uric acid contained in the bird’s feces, so the amount of waste is equal to the amount of raw material that will later be partially converted into ammonia.
Temperature, pH, and hygrometry directly influence the development, multiplication, and activity of microorganisms that ferment uric acid. If the organisms are in optimal conditions, there is greater fermentation and, therefore, a significant release of ammonia.
The consequences in animals are no less critical since they cause sensitization in their organisms with:
- Respiratory and ocular difficulties, a food discomfort that, consequently, acts on the assimilation of food, negatively influencing GMQs.
- Pododermatitis due to litter scabs. The ground is much less conducive to movement, affecting the birds’ foraging and welfare and their exposure to pathogens.
- A weakening of your immune defenses. In an epidemic, your viral sensitivity will be even higher.
From a financial point of view, if the number of FPD is too high, there will be a higher number of seizures at the time of slaughter. Nor can the risk of cross-contamination in poultry meat and, therefore, of consumers be forgotten.
Therefore, bacteria proliferate without adequate sanitary conditions, such as E. Coli, Campylobacter spp., or Salmonella spp. Some cause diseases in birds, diarrheal diseases in humans, and even in some cases, Guillain-Barré syndrome. Furthermore, according to David Acheson and Ban Mishu Allos, approximately 50 to 70% of gastroenteritis diagnoses are due to Campylobacter infection after consumption of contaminated chicken.
In addition, pathogenic microorganisms enter the building through carriers such as humans or insects such as the tenebrious (Alphitobius diaperinus).
It is essential to follow biosafety rules to minimize contamination risks.
Environmental problem
Finally, an environmental problem is caused by discharges, particularly ammonia, through the ventilation in poultry houses. Their excessive deposition in the natural environment can lead to acidification and eutrophication.
These gases can also negatively impact the chickens’ health and those of the farmers who circulate daily in the buildings (ITAVI, Technical Institute of Poultry – France).
In addition, they can recombine in the atmosphere with oxides of nitrogen and sulfur to form fine particles (PM2.5). It is now known that chronic exposure, even at low levels, is more harmful than point exposure at a high peak.
In addition to gas releases, bacteria present in aerosols inside farms have also been shown to be ventilated outside buildings (Chinivasagam HN, Tran T, Maddock L, et al., 2010 and Bayko Baykov, Michail Stoyanov, 1999), creating potential cross-contamination with surrounding crops, humans, and wildlife.
The importance is to control all these parameters to limit the concentration of ammonia and bacterial growth, which is essential for the birds, the operators, and the environment.
This can be done by working on the litter and its disinfection, adding amendments to the litter, ventilation, adapted drinkers, etc.
The mechanical work of the bed allows its aeration and drying, consequently considerably reducing the risk of fermentation and ammonia emissions. This also causes better soil softening, an essential factor in developing pododermatitis.
Also, litter disinfection regularly during rearing allows the bacterial mass to be drastically reduced. Reducing hygrometry can be done with more efficient ventilation (William et al., 1991) and also implies a reduction in ammonia emissions into the ambient air.
Poultry is, therefore, subject to pressure induced by pathogens, which enter and spread in buildings through different vectors, such as humans or insects.
The environment of the buildings must be controlled, particularly the hygrometry since it provokes the accumulation of litter, the formation of pododermatitis, and the release of ammonia. Poultry farming also represents a danger to the environment through the eutrophication of the environments it causes, but also to humans through the pollution it induces. Therefore, the solutions that exist today to fight and minimize the impact of these factors on animals, operators, and the environment will be detailed.
