Swan, K.-M., Telkänranta, H., Munsterhjelm, C. et al. 2021. Access to chewable materials during lactation affects sow behaviour and interaction with piglets. Applied Animal Behaviour Science 234, 105174.
We investigated how providing chewable materials to piglets during the early weeks of life affect sow behaviour, sow and piglet interaction and sow health in pens with farrowing crates. We divided 59 pregnant sows into two treatment groups: the Control group (C, n = 29) and the Rope-Paper group (RP, n = 30). Piglets in the C group had the minimum enrichment required by Finnish legislation. For the RP group, we added sisal ropes and non-glossy newsprint paper. We recorded the behaviour of sows and their litters for a four-hour period during the first 7–18 days of life of the piglets. Skin and udder damage of the sow was recorded once a week five times. Behavioural data was divided into two categories according to the age of the litters. The first group contained litters aged from 7 to 13 days (n(RP) = 22 n(C) = 22) and the second group litters aged 14 days or older (n(RP) = 24 n(C) = 24). Younger piglets (age 7–13 days) in the RP group manipulated the udder more frequently (p < 0.01) and the duration of udder manipulation was longer than in the C group (p = 0.02). Further, the RP group had more udder contact events in which 20 % or less of the piglets took part and in which less than 50 % took part (p < 0.01 for both). Older piglets (age ≥ 14 days) in the RP group touched the sows’ body more frequently (p < 0.05). Sows in the C group were standing (p = 0.01), eating (p = 0.04) and performing oral-nasal manipulation (p < 0.01) more often. In the C group, repeated measures of skin lesions differed significantly between observation days (p = 0.00), sows tending to have a higher skin lesion score in observation week 5, with a median score of 1.5 (1–3), than in observation week 4, with a median score of 1 (1–2) (p = 0.06). In conclusion, piglets that had access to chewable materials after birth made more contact with the sow during lactation. However, sows in the C groupperformed more active behaviour. The behavioural mechanisms underlying these changes are not yet clear. Further investigations of the usage of chewable materials in farrowing units equipped with crates and their effects on the behaviour of sows and piglets are therefore warranted.