Projecten per jaar
Group housing is often assumed to improve the welfare of gregarious species. Whether this is actuallythe case depends on the advantages (e.g. more opportunity for social and locomotor behaviour) and dis-advantages (e.g. increased fighting and wounding) induced by the specific housing type. We evaluatedthe effects of a semi-group system (grouping four does for half of each reproductive cycle) on welfare bycomparing it to single-doe cages. Compared to this control, our semi-group system provided more totalspace when does were grouped and more space per doe (a confounding deemed necessary to avoid overtaggression). Thus, the results should be interpreted as a systems comparison. In each of the four exper-imental cycles semi-group does were housed separately for 21 days around parturition and housed innewly assembled groups for the next 21 days. Behaviour was observed in semi-group and single-doe sys-tems immediately after the second time semi-group does were mixed, and during five timeslots dividedover the second experimental cycle. Skin lesion and weight loss were determined in each cycle. Adrenalweight was measured post-mortem. Semi-group systems with different floor types were included butfloor type effects were scarce and semi-group systems were therefore treated as one category. In thetimeslot subsequent to mixing semi-group does spent a greater percentage of their time on locomotion(4.3 vs. 0.7%, P < 0.01) and social sniffing/grooming (1.4 vs. 0%, P < 0.01) than does in single-doe cages.Such differences also occurred in later timeslots, but were much smaller (e.g. midnight locomotion D12:0.8 vs. 0.2%, P < 0.05, midnight social sniffing/grooming D12: 0.4 vs. 0%, P < 0.01). Attacking/chasing fol-lowed a similar pattern (following mixing: semi-group 5.3% vs. single 0%, P < 0.01; midnight D12: 0.01vs. 0%, P < 0.10). A high percentage of semi-group does were slightly (58%) or severely (20%) wounded.Semi-group does spent a smaller percentage of the timeslot following mixing in bodily contact withadults than does from single-doe housing (who could only make contact through the wire walls, 1.6 vs.11.8%, P < 0.01). Even 12 days after mixing the percentage of time semi-groups spent in bodily contact didnot exceed that in singles (P > 0.10). In experimental cycle one only, semi-group does lost more weightduring late lactation than singles (192 vs. 10 g, P < 0.01). Adrenal weights did not differ between systems(P > 0.10). Further research will be needed to design semi-group systems with a more favourable balancebetween advantages and disadvantages.
|Tijdschrift||Applied Animal Behaviour Science|
|Publicatiestatus||Gepubliceerd - 2015|
- 1 Afgerond