Reviewing group housing for lactating sows
The animal Article of the Month for March is entitled ’A review of sow and piglet behaviour and performance in group housing systems for lactating sows’.
Commercial use of group housing systems for lactating sows is currently limited, but the recent transition to group housing during gestation in the EU may result in a renewed interest in such systems. The evaluated group housing systems for lactating sows differ in many aspects regarding management and layout but, compared with individual housing, generally provide more environmental complexity, more freedom of movement for the sows and more freedom to express natural behaviours, for example related to social interactions.
In multi-suckling systems, sows and their litters are grouped together. Pre-weaning mingling of litters benefits piglet social development and may improve adaptation to the post-weaning situation. Furthermore, multi-suckling systems have the potential to promote pre-weaning piglet feed intake by social learning from the sows and other piglets (e.g. learning where and what to eat). Moreover, group-housed sows can be stimulated to ovulate during lactation more easily. This provides opportunities for insemination during an extended lactation period, which benefits piglet development.
On the other hand; group housing also poses some risks, such as disrupted nursing behaviour and a higher level of piglet crushing in the multi-suckling phase compared with individual housing. In get-away systems, which include a separate communal area accessible to sows only, there is a risk for early cessation of nursing. In order to reduce such risks, gradual transitions in the social and physical environment around gestation, farrowing, grouping and weaning seem important. For instance, compared with individual housing, pre-weaning piglet growth seems to be higher in systems with few and gradual transitions, compared to systems with abrupt transitions, which may be related to stress and disturbed nursing behaviour.
An important reason to write this review on group housing systems for lactating sows was to gain more insight in the success and risk factors that may be encountered in the development of such a system. Based on these insights, a multi-suckling unit for five sows has been built at Swine Innovation Centre in Sterksel, The Netherlands. The system has five farrowing pens connected to a communal area with areas designated for lying, eating and defecating (see pictures). After grouping of litters at approximately one week of age, piglets can eat together with the sows that are floor-fed in open access stalls in the communal area. Additionally, piglets have access to piglet feed in an area accessible to the piglets only. Furthermore, gradual transitions in social and physical environment are applied; the sows originate from the same gestation group, have access to loose farrowing pens and thus maintain their freedom of movement around farrowing, and can maintain social contact before and during lactation. Additionally, grouping of litters does not involve relocation to an unfamiliar area; the communal area is accessible to the sows before and during lactation (i.e. get-away housing during the first week post-partum). The system will be further developed in the coming years, aiming at a commercially feasible group lactation system that benefits sow and piglet health and welfare.
Authors: S.E. van Nieuwamerongen, J.E. Bolhuis, C.M.C. van der Peet-Schwering and N.M. Soede
The animal Article of the Month is selected by the Editor-in-Chief and is freely available for one month