Abstract
Group housing is becoming the standard for many farm animal species, as
it is seen as a more welfare friendly way of keeping gregarious animals.
Aggression between female breeding rabbits currently obstructs the
implementation of group housing for this species. Lack of social
experience during the rearing period may be one reason why breeding
rabbits can act (excessively) aggressive when grouped as adults. To
study this, we either reared breeding rabbits with their same-litter
siblings and mother only (“litter-only”) or reared four litters and
their mothers together from 18 days of life on (“communal rearing”). The
litter-only rabbits were born from individually housed mothers, whereas
the communally reared rabbits were born from mothers that were group
housed during the last three weeks of gestation. After their first
kindling, female rabbits from both rearing strategies were housed in
groups of four or eight individuals (at an equal space allowance per
doe) to assess rearing and group size effects on post-grouping
behaviour. Within both treatments we also measured the ano-genital
distance at birth (an indicator of masculinization) and studied its
relation to adult agonistic behaviour. Communal rearing and larger
groups were expected to decrease agonistic behaviour and wounding,
whereas rabbits with a longer ano-genital distance were expected to show
more offensive agonistic behaviour. The first two hypotheses were not
confirmed. Communally reared and litter-only rabbits did not differ
significantly in the frequency of their offensive or defensive agonistic
behaviour directly post-grouping, or in the severity of wounds
sustained in the first three days after grouping (P > 0.10).
Communally reared rabbits sniffed/groomed their pen mates less often
than litter-only rabbits (P < 0.05). A tendency for a higher
frequency of offensive agonistic behaviour in larger groups was found
(P < 0.10) and the decrease in defensive agonistic behaviour over
time that was observed for the smaller groups was lacking in the larger
groups. The third hypothesis was confirmed: female rabbits with a
greater ano-genital distance at birth showed more offensive agonistic
behaviour upon grouping as adults (rs = 0.5, P < 0.05).
When this relation was studied within the separate rearing strategies,
it was only confirmed within the communal rearing treatment, possibly
suggesting that prenatal social stress increased both ano-genital
distance and aggression. To conclude, communal rearing and larger groups
did not decrease agonistic behaviour in breeding rabbits, whereas
ano-genital distance measurements may be useful when selecting less
aggressive breeding rabbits (although this method may be specifically
applicable to communally reared rabbits).
Original language | English |
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Pages (from-to) | 53-60 |
Number of pages | 8 |
Journal | Applied Animal Behaviour Science |
Volume | 182 |
Early online date | 23 Jun 2016 |
DOIs | |
Publication status | Published - Sept 2016 |
Keywords
- Agonistic behaviour
- Early experience
- Group housing
- Masculinization
- Pre-natal effects
- Social behaviour