Integrated assessment of stunning techniques in poultry slaughterhouses. Literature-based indicative assessment of environmental factors and other aspects
Integrale beoordeling verdovingstechnieken pluimveeslachterijen. Indicatieve beoordeling van milieu- en andere aspecten op basis van literatuurstudie
26 May 2012, PDF |
56 pages |
Morgenstern PP , Lambooij E , Baltussen WHM
RIVM Report 609021080
Most poultry slaughterhouses in the Netherlands stun poultry in electric water baths. An alternative method for stunning involves the use of carbon dioxide in a two-step/concentration procedure. The primary advantages of the gas anaesthesia method are associated with improved animal welfare and working conditions. Other aspects of poultry slaughterhouses, such as those pertaining to the environment and economics, can be either positively and negatively affected by this method. These are the results of a study conducted by the National Institute for Public Health and the Environment (RIVM), Agricultural Economics Research Institute (LEI) and the Animal Sciences Group of the Wageningen University Research Centre (WUR). With respect to animal welfare, the advantage of gas stunning is that poultry are not restrained in shackles while conscious and there is no chance of the stunning being ineffective. The shackling of unconscious birds also has benefits in terms of working conditions, specifically in the amount of physical labour involved and the amount of dust released. Gas stunning is more favourable for the environment because it leads to the use of less water and causes fewer dust and odour problems. However, in comparison to electric stunning, gas stunning is associated with higher energy consumption. Gas stunning is more expensive in terms of initial acquisition/installation and operational costs (energy consumption), but it does result in a higher quality product (e.g. fewer broken bones and bruising). Some segments of the market may therefore view its introduction as a positive development (i.e. higher profits). The switch to gas stunning will directly affect the competitiveness among poultry slaughterhouses, with the larger, more productive slaughterhouses ultimately having the most benefit. The replacement of electric water baths by gas stunning will not influence consumer prices. The reason for conducting this research is that gas stunning methods have been incorporated in a European Directive (IPPC) as Best Available Technique (BAT) for stunning poultry, but there has been no in-depth study of the environmental consequences of these stunning techniques. The Ministry for Housing, Spatial Planning and the Environment Inspectorate (VROM-Inspectorate) therefore requested the RIVM to carry out a detailed survey of the environmental and other issues associated with the various gas stunning techniques, as described in the literature, and to compare these techniques with electric stunning.