Gnawing blocks as cage enrichment and dietary supplement for does: performance, intake,and behaviour

One hundred and five pregnant rabbit does housed in conventional wire cages received during one complete reproductive cycle no enrichment (controls) or one of three different gnawing blocks hanged up with a wire at the wall of the cage. The three different blocks had the same basal components but additionally wood mash (WM), wood mash + chicory pulp (CP) or wood mash and inulin syrup (I) were respectively incorporated. Weight development during the lactation was comparable except in does that received the WM blocks. These females had a significant lower weight (P<0.05) at different time points compared to controls. Litter weight or kit weight was not significantly different at any of the time points measured but again the treatment with WM blocks had the lowest weight. The consumption of blocks during the whole reproduction cycle (42 days) was 11.0; 6.8 and 4.4 g/day/cage for WM, CP or I enriched blocks, respectively. A very large variability in consumption of blocks was observed between females. This varied between 1 and 5 (I or CP group) or even 1 and 9 blocks (WM group) per reproductive cycle. In each group 5 females were observed for 1 hour 3 days before the expected parturition and at 2 time points during the lactation. Although the presence of a block did not significantly increase the total number of behavioural transitions, locomotion and intake behaviour were significantly (P<0.05) increased when a gnawing block was available. The period of observation influenced the frequency of many behavioural transitions and was before parturition significantly higher than post parturition, respectively 56.1 vs. 13.7 (Week 1, P<0.01) and 25.1 (Week 2, P<0.01). Based on the consumption pattern, the hardness and behaviour this gnawing blocks could be considered as cage enrichment and those with the chicory pulp fitted best with the objective.