A multifactorial evaluation of different reproductive rhythms and housing systems for improving welfare in rabbit does

The most widespread reproductive rhythm practiced in rabbit farming is based on artificial insemination (AI)performed at around 11 dayspospartum. This approach results in high production rates, but requires high yearlyreplacement of animals that cannot sustain the enormous energy demand. Rabbit does that are in energy deficithave relatively short reproductive careers. Moreover, current housing systems do not allow animals to expressthe typical behavioural pattern of the species, with presence of abnormal behaviours that contribute to reducewelfare. Thus, the present study aimed to evaluate the best combination of housing systems and reproductiverhythms through multiple indicators (performance, behaviour, corticosterone assessments) to improve does’welfare. A total of 110 nulliparous rabbit does of the Grimaud hybrid maternal line were randomly allocated to 2different housing systems, an innovative type of cage, Combi cage (C),vs. the conventional cage currently usedin intensive farming, Standard cage (S), within which 3 reproductive rhythms: Intensive (I), with AI 11 dayspostpartum; Alternating (A), with AI alternated between 11 and 30 dayspostpartum; or Extensive (E), with AI 30dayspostpartum, were applied. All rabbits underwent 6 consecutive reproductive cycles, according to a multi-factorial balanced experimental plan (2 × 3), as follows: CI (20 does)vs. CA (20 does)vs. CE (20 does)vs.SI(5does)vs. SA (5 does)vs. SE (5 does). At the main critical phases (AI, kindling, and peak lactation), we conductedreproductive, behavioural, and hormone assessments (salivary corticosterone). CE group showed higher motoractivity, lower feeding rates, and increases in number of live kits and weaned kits, which resulted in betterreproductive performance in the C cages. The SA group displayed the highest number of live-born kits/litter(P < 0.02), the highest total weight of the weaned litter (P < 0.01), and the lowest pre-weaning mortality(P < 0.04) among S cages. The housing system also influenced behaviour: S does displayed the highest fre-quencies of self-grooming (P < 0.01), feeding (P < 0.001), and stereotypical behaviours (sniffing and bitingbars, P < 0.01), which indicated frustration from a lack of stimuli and consequent boredom. Based on ourresults, we concluded that AI after kit weaning (E) was the best reproductive rhythm for does in C cages, and theA rhythm was best for does in S cages. However, from an ethological point of view, in the S cages, stereotypesrelated to the small size of the housing system still remain