Behaviour and welfare of growing rabbits housed in cages and pens Angela Trocino a,n , Eirini Filiou b , Marco Tazzoli b , Daniela Bertotto a , Elena Negrato a , Gerolamo Xiccato b a Department of Comparative Biomedicine and Food Science, University of Padova, Viale dell’Università 16, I-35020 Legnaro, Padova, Italy b Department of Agronomy Food Natural Resources Animal and Environment (DAFNAE), University of Padova, Viale dell’Università 16, I-35020 Legnaro, Padova, Italy article info Article history: Received 3 February 2014 Received in revised form 30 May 2014 Accepted 31 May 2014 Keywords: Housing Behaviour Reactivity Corticosterone Growing rabbits abstract The present study compared behaviour, fear and stress levels of 456 crossbred rabbits reared in bicellular wire-net cages (2 rabbits/cage) with top and wire floor or open-top collective pens (20 to 54 rabbits/pen) with wooden slatted floor. The effect of pen size (small vs. large) and stocking density (12 vs. 16 rabbits/m 2 ) in collective pens was also evaluated. The rabbits kept in collective pens rested more than those in bicellular cages (82.1% vs. 77.6% of observed time; P o0.01), spent less time feeding (7.8% vs. 10.9%), allo-grooming (0.65% vs. 1.58%) and more time moving (0.81% vs. 0.35%) (P o0.01). The percentage of rabbits sensitive in the tonic immobility test was lower in rabbits kept collectively compared to those in bicellular cages (76.6% vs. 93.8%; P ¼0.03). In the open field test, the rabbits kept in collective pens moved less (40.4 s vs. 57.2 s; P o0.001) and explored the arena for a shorter time (345 s vs. 371 s; P o0.001) than rabbits housed in bicellular cages; instead, these rabbits stood still for a longer period of time (82.1 s vs. 38.7 s; P o0.001). The rabbits kept in collective pens displayed a higher hair corticoster- one level (15.7 ng/g vs. 6.7 ng/g for rabbits from the cages; P o0.001). Within collective housing systems, stocking density had no effect whereas increasing pen size numerically reduced the time rabbits spent eating (8.30% vs. 6.55%), self-grooming (6.39% vs. 5.47%) and time spent resting (81.1% vs. 84.1%). In conclusion, rabbits housed in collective pens displayed a more complete behavioural pattern, despite resting more; they were more bold toward humans, but more fearful in a new environment than rabbits from cages. In the tested conditions, pen size and stocking density within collective systems exerted only a weak effect on behaviour, fear and stress levels of meat rabbits. & 2014 Elsevier B.V. All rights reserved. 1. Introduction When rabbits raised for meat production are housed in bicellular (2 animals) or small-size (4 to 6 animals) cages, as are used in European Countries, they are unable to express typical behavioural patterns, such as hopping, exploring and alerting (Trocino and Xiccato, 2006; Verga et al., 2007). When rabbits are reared in groups of two or more animals, both the cage/pen dimensions and the group size may affect the expression of different beha- viours and the quality of social interactions (Buijs et al., 2011a, 2011b, 2011c; Morisse and Maurice, 1997; Postollec et al., 2006, 2008). Unsuitable environment and social relationships/isola- tion may negatively affect stress levels and behaviours and, consequently, the animal immune response and Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/livsci Livestock Science http://dx.doi.org/10.1016/j.livsci.2014.05.035 1871-1413/& 2014 Elsevier B.V. All rights reserved. n Corresponding author. Tel./fax: þ39 49 8272583. E-mail address: angela.trocino@unipd.it (A. Trocino). Livestock Science 167 (2014) 305–314