Economic impact of decreasing stocking densities in broiler production in Belgium.

Stocking density is a prominent topic in public debates on animal welfare and was one of the reasons for the European Commission to set limits to the stocking density on broiler farms. The objective of this paper was to calculate in detail the financial impact of changes in technical and management variables due to decreasing stocking densities in line with new European Union (EU) regulations. Therefore, the productive performance indicators such as BW, mortality, or feed conversion and farm technical data such as water consumption and heating of 3 independent experiments conducted at a poultry research station in Flanders (Belgium) were combined. Using the partial budget technique only those elements that change with stocking density have been taken into account. Reducing stocking density implies a recalculation of all costs on a reduced number of birds. This yields an economic situation that leaves hardly any profit margin for most of the broiler producers under the present market conditions. It was found that the critical threshold of stocking density for maintaining profitability under the present market and technical conditions is around 46 kg/m(2), thus well above the EU maximum of 42 kg/m(2). It is shown, however, that with changing broiler feed and meat prices, the impact might be less negative in economic terms.

The transmission color value: a novel egg quality measure for recording shell color used for monitoring the stress and health status of a brown layer flock.

Stress and diseases have the potential to influence the deposition of eggshell pigmentation during egg formation. Therefore, defining the shell color of eggs on a daily basis could be a representative method for monitoring stress or health status of a flock and maintaining good performance. A novel way of measuring eggshell color based on visible-near infrared transmission spectroscopy transmission spectra was defined: the transmission color value (TCV). The TCV was calculated as the ratio between the transmission at 643 nm (maximum absorbance of the pigmentation molecule protoporphyrin IX) and the transmission at 610 nm (a reference wavelength). Experiments were carried out to investigate the relevance of TCV for monitoring flock stress and health or even anticipating any factors unfavorable to performance. In 2 small experimental flocks, deliberate heat stress challenges were applied. A medium-scale experimental flock in an aviary was monitored on a daily basis during the whole productive period. From the deliberate heat stress challenges, it was seen that stress had a significant effect on eggshell pigmentation. This observation was confirmed in a daily monitored flock, in which, for example, an infectious bronchitis infection occurred. These stress situations were quickly reflected by an increased TCV value: more transmission due to less pigmentation and hence less absorbance at the pigmentation wavelength. Furthermore, for the observed problems in the daily monitoring, the TCV value signaled the problem earlier (4 d) than the average egg weight or even signaled when the other parameters did not signal anything. Measuring the TCV of all eggs produced on a daily basis provides relevant information on the stress or health status of a flock of brown layers. This could be used as an early detection of stress situations or emerging diseases, even before important quality and health damage can occur.