Societal concern related to stocking density, pen size and group size in farm animal production

Carcass traits and meat quality of rabbits reared in conventional cages (0.385 m2), small pens (0.662 m2) or large pens (4.052 m2) at a similar stock density of 15 rabbits/m2 were compared (n = 30 per group). Pens contained an elevated platform. Slaughter weight (SW; P < 0.01) and cold carcass weight (P < 0.05) decreased in the order of Cage < Small pen < Large pen groups. SW and cold carcass weight were 7% lower in rabbits housed in large pens than in cages. Dressing out and meat-to-bone ratio were not influenced by the housing system. Percentage of fat deposits was highest in caged rabbits (+0.15 point for scapular fat and +0.26 point for perirenal fat compared to rabbits reared in large pens P < 0.05). Rabbits housed in large pens had a bigger proportion of hind part (+1 point), and meat colour was shifted towards greater a* values (P < 0.01) compared to caged rabbits. Water holding capacity and shear test parameters in longissimus lumborum muscle, lipid content and shear test parameters of abductor cruralis cranialis, biceps femoris and semitendinosus muscles were not affected by the housing system. Tibia and femur bone moment of inertia increased in the order of Cage < Small pen < Large pen groups (P < 0.05), whereas elastic modulus, which is a measure of intrinsic stiffness, was highest in caged rabbits. This study showed that large pen housing altered carcass traits independently and increased meat redness and fracture resistance of tibia and femur.

Influence of cage or pen housing on carcass traits and meat quality of rabbit.

Different rearing systems for fattening rabbits: Performance and carcass characteristics.

The AGRI committee of the European Parliament requested EFSA to assess the welfare of rabbits farmed in different production systems, including organic production, and to update its 2005 scientific opinion about the health and welfare of rabbits kept for meat production. Considering reproducing does, kits and growing rabbits, this scientific opinion focusses on six different housing systems, namely conventional cages, structurally enriched cages, elevated pens, floor pens, outdoor/partially outdoor systems and organic systems. To compare the level of welfare in the different housing systems and rabbit categories, welfare impact scores for 20 welfare consequences identified from the literature were calculated, taking their occurrence, duration and severity into account. Based on the overall welfare impact score (sum of scores for the single welfare consequences), obtained via a 2-step expert knowledge elicitation process, the welfare of reproducing does is likely (certainty 66-90%) to be lower in conventional cages compared to the five other housing systems. In addition, it is likely to extremely likely (certainty 66-99%) that the welfare of kits is lower in outdoor systems compared to the other systems and that the welfare is higher in elevated pens than in the other systems. Finally, it is likely to extremely likely (certainty 66-99%) that the welfare of growing rabbits is lower in conventional cages compared to the other systems and that the welfare is higher in elevated pens than in the other systems. Ranking of the welfare consequences allowed an analysis of the main welfare consequences within each system and rabbit category. It was concluded that for reproducing does, as well as growing rabbits, welfare consequences related to behavioural restrictions were more prominent in conventional cages, elevated pens and enriched cages, whereas those related to health problems were more important in floor pens, outdoor and organic systems. Housing in organic rabbit farming is diverse, which can result in different welfare consequences, but the overall welfare impact scores suggest that welfare in organic systems is generally good.

Health and welfare of rabbits farmed in different production systems.

Behaviour and use of space in fattening rabbits as influenced by cage size and enrichment

The effects of a (30 cm high) elevated platform as an enrichment structure on the behaviour and performance of fattening rabbits kept in groups were investigated. Three housing systems for fattening rabbits were compared using a stocking density of 15 rabbits m -2 . The rabbits were housed either in large pens (3.67 m 2 plus a platform of 0.39 m 2 ; with 60 rabbits per pen) or in small pens (0.503 m 2 plus a platform of 0.159 m 2 ; with 10 rabbits per pen), or in conventional standard cages (0.39 m 2 , with 6 rabbits and without any enrichment) from 31 to 72 days of age. The conventional cages without a platform were used as a control and reference model. Rabbits housed in each small pen or in each cage belonged to the same litter, and the 60 rabbits sharing the same large pen were from six or seven litters. At the end of fattening, rabbits reached the weight of 2,508 g in cages, 2,397 g in small pens, and 2,340 g in large pens; the only significant difference was daily weight gain which was better in cages than in both pens. There was no difference in growth parameters between the two types of pens. The mortality rate was less than 1% for all treatments. No sanitation problems or severe lesions were seen with rabbits even those reared in large pens and large groups. Neither housing systems, nor elevated platform affected activities such as dietary intake or resting. The use of the platform appears to depend upon the amount of space available; in a large pen, an elevated platform can be utilised as an exercise structure while in a small pen it was used more as simply extra space to occupy.

G. Postollec

Papers

The effect of pen size and an enrichment structure (elevated platform) on the performances and the behaviour of fattening rabbits

The effect of housing system on the behaviour and growth parameters of fattening rabbits