A survey about the welfare problem "toe pecking" in Swiss laying hens

In recent years, outbreaks of toe pecking (TP) have been reported in laying hen flocks on Swiss farms leading to increased mortality. A literature search revealed a 17.3-fold lower number of scientific articles and a 20-fold lower number of citations about TP compared with feather pecking. Therefore, the aim of our study was to assess the associations of TP with housing and management factors. An online survey among Swiss egg producers yielded 96 fully completed questionnaires on the outbreak of TP and housing and management factors with half of the producers reporting TP. Data from the survey were analyzed by chi 2 tests, Fisher's Exact test, and generalized mixed models. According to the survey, white flocks were more affected than brown flocks (Fisher's Exact Test, P = 0.01, N = 79). Several factors regarding management and housing were associated with TP (i.e. metal slats: F1,50 = 5.61, P = 0.02; direct sunlight: F1,50 = 7.52, P = 0.008, high frequency light sources: odds ratio: 4.13 (1.11, 15.32)). Farms with problems with E.coli during the last 5 years were more likely to have an outbreak of TP (F1,50 = 5.69, P = 0.02). The type of housing (aviary/floor housing/access to a range) and laying rate were not associated with the occurrence of TP. According to the farmers, dimming the lights was the only effective intervention to reduce the problem (Fisher's Exact Test: P < 0.0001). In conclusion, TP seemed to be multifactorial, could be reduced by a reduction of light, and affected mainly white hybrids.