Table 3

Occurrence of diseases (divided into main categories) in laying hen flocks submitted to SVA in 2001–2004.



Bacterial diseases
Viral
diseases
Parasitic diseases
Cannibalism

Housing system
Total no. of flocks1
N
%
N
%
N
%
N
%
Cages2
20
13
65.0
6
30.0
2
10.0
1
5.0
Litter-based systems3
129
94
72.9
15
11.6
23
17.8
24
18.6
Free range4
23
17
73.9
1
4.4
5
21.7
6
26.1

1No. of examined flocks. Note that each flock may have several diagnoses.

2Includes conventional battery cages and enriched cages.

3Includes single-tiered floor systems and multi-tiered aviary systems.

4Flocks housed in litter-based systems indoors, with access to outdoor pens and pasture, including organic flocks.

Fossum et al. Acta Veterinaria Scandinavica 2009 51:3   doi:10.1186/1751-0147-51-3