Göttingen Minipigs are social and curious animals with a strong motivation for performing various types of social behaviour. Appropriate social housing should therefore be prioritized and unnecessary regrouping should be avoided.
Forming new groups
Changes in group composition, such as removal or addition of animals, can lead to changes in group dynamics and instigate the formation of new hierarchies. However, keeping minipigs in stable groups throughout their lives is not always possible due to logistical or study circumstances.
Regrouping of animals is performed successfully on a regular basis at Ellegaard Göttingen Minipigs. Regrouping females can be done at all ages, whereas fighting tendencies amongst males increase in severity with age. Hence, we do not recommend regrouping male minipigs older than approximately 6 months of age. In general, several measures can be taken to support smooth hierarchy and stable group formation. We suggest taking the following into consideration when regrouping minipigs:
Ease the transition
If possible, acquaint the minipigs beforehand by housing them in adjacent pens before regrouping them in the same pen.
Pen area
If possible, regroup pigs in neutral pens, i.e., pens of which none of the pigs have affiliations or territoriality.
Space
Ample space and possibly visual barriers in the pen ensure less stress when forming new hierarchies. An important part of establishing a hierarchy is the possibility for the submissive pig to retract from the confrontation. Adjacent pens and/or the corridor can be used if necessary. Once the hierarchy is established, the pen size can be reduced if necessary.
Distractions
Provide plenty of distractions: Bedding such as straw, food scattered on the floor, ice blocks, toys, etc. We find that stimulating the olfactory sense, e.g. with scented toys, works particularly well in alleviating the severity/duration of hierarchal fighting.
Supervision
Regrouping should be performed under close observation by staff to enable intervention if hierarchal fighting is prolonged or severe. Hence, regrouping early in the workday is recommended.
Compatibility
Determining the social ranking of a minipig in the group can be challenging, but if known, it is easier to regroup a dominant and a submissive minipig, rather than two dominant minipigs.
When is single-housing necessary?
Exceptions to the principle of social housing are animals where veterinary or study needs dictate otherwise, breeding sows where farrowing is imminent, and adult breeding boars, who have a solitary nature. However, even adult boars may be housed together in groups if they remain in the same group they were raised in, under careful supervision of group dynamics.
Socialising measures for single-housed minipigs
If social housing is not possible, steps should be taken to ensure that minipigs can interact with conspecifics by being able to see, smell, hear, and touch each other (e.g. snout contact). This can be achieved by housing minipigs in neighbouring pens separated by bars, transparent walls, and/or walls with holes.
Furthermore, extra measures should be taken to ensure a suitable enrichment program for single-housed animals, e.g. extra, positive staff interactions, or supervised physical interaction sessions with other minipigs.
Social behaviours are further enabled by letting the minipigs walk in the corridors of the barriers. This provides social enrichment, new stimuli, and potential for exercise, and is beneficial for all minipigs regardless of number of pen mates, but it is even more important with single-housed animals. Also, it has the added benefit of accustoming the minipigs to new surroundings which may improve mental resilience towards changes and events later in life.
