Sow free farrowing behaviour: Experiential, seasonal and individual variation

Abstract

Although sow confinement at farrowing is inherently stressful, farrowing crates remain in widespread commercial use. Sows adapt to their environment, however adaptation may be counter-productive if the farrowing system changes. The current study observed the behaviour of second parity sows throughout farrowing in a straw pen system to determine if their previous farrowing experience, in either the same pen system (n=11) or a temporary confinement crate system (n=11), affected current nest-building, farrowing and nursing behaviour. Data were analysed using PROC MIXED, with sow ID as the repeated subject.Sows which previously farrowed in pens tended to have a higher pre-partum peak nesting intensity (P = 0.081), and throughout parturition exhibited increased lateral lying (P < 0.01), decreased ventral lying (P < 0.001), decreased sitting (P < 0.01) and a decreased frequency of dangerous posture changes (P < 0.05). Post-partum, sows that previously farrowed in pens had a lower percentage of sow-terminated nursing (P < 0.01), a longer average duration of successful nursing bouts (P < 0.05) and a lower frequency of sow-terminated nursing bouts (P < 0.001). Seasonal effects were also seen in this naturally-ventilated system, both pre-and post-partum, with autumn/winter farrowings associated with more prepartum nesting (P < 0.01), a higher pre-partum peak nesting intensity (P < 0.05), a longer average duration of successful nursing (P < 0.05) and a higher percentage of nursing bouts ending with piglets asleep at the udder (P < 0.05) than in the spring/summer. Individual variation in pre-partum nesting behaviour was associated with differences in parturient and post-partum behaviours. The results show that the prior experience of confinement, or a change of farrowing system, significantly affects sow farrowing behaviour in free farrowing pens, which may compromise the welfare of both sows and piglets.

Freedom to Grow: Improving Sow Welfare also Benefits Piglets

“…For instance, Hales et al [ 35 ] found that mortality increased with increasing parity, which is in line with our findings, as well as with increasing litter size. King et al [ 36 ] found that the sows’ previous experience in a farrowing system affected piglet mortality. Thus, older sows in this study which were housed in the free treatment may have achieved lower rates of mortality had they previously experienced rearing piglets in a free lactation system.…”

Development and application of an image acquisition system for characterizing sow behaviors in farrowing stalls

“…Thermal needs, for example, are different for lactating sows and suckling piglets (MWPS-8), yet only one air temperature exists for their shared space. Many other production factors are changing as well, such as seasonal effects (King et al, 2018) and differences in breeding lines (Shurson & Irvin, 1992;Bloemhof et al, 2008). Mitigating these dynamic factors is nontrivial and such challenges contribute to an annual average US pre-weaning mortality of 17.8% (Stalder, 2018), amounting to substantial economic loss.…”

Review of Temporary Crating of Farrowing and Lactating Sows

“…As a result, farmers need to either build new facilities or reduce the number of pens, where the latter includes reduction in herd size, both involving long-term cost implications. Even though farrowing and lactation pens basically only need places for sows to eat, drink, rest, and dung and a creep area for piglets, the differences in dimensions of sows and piglets, the increasing litter sizes, the work conditions for caretakers, and differences in construction lead to a large variation in the pens available and used both in trials ( 32 , 37 ) and on farms ( 19 , 28 , 38 , 39 ). The higher neonatal piglet mortality observed in studies where sows were loose during farrowing compared to sows that were in crates ( 5 , 24 , 54 ) has led to consideration of the opportunity to temporarily confine the sows in pens designed for loose sows ( 26 , 28 , 32 ).…”

“…Although it is not specified, it is expected that the measurements reported in publications regarding width of the farrowing crate are inside dimensions and so available for sow and piglets when nursing while the sow is confined. In the papers, which have specified the dimensions, the measurements range from 52 cm ( 30 ) to 90 cm ( 37 , 47 ), where 52 cm is insufficient for at least full-grown Danish crossbred sows ( 56 ). When the sows are let loose, features in pens such as the “wings” or similar structures used to confine sows, and the positions they are “mounted” in when the sows are loose, influence not only the space available for sows and possible planar width (i.e., width at sow's shoulder height) but also the safety zones for piglets.…”

“…This makes it difficult to compare the pens and to recommend which pen to use in future trials or farm installation or in assisting other stakeholders such as policy-influencers and policymakers. According to the information available ( Table 2 ), the pens differ in total footprint from 2.66 m 2 ( 23 ) to 7.4 m 2 ( 32 ) and 9.22 m 2 in a pen with access to an outdoor area ( 37 ). The area available for sows when loose differs from 1.9 m 2 ( 23 ), 5.3 m 2 ( 27 ), to 7.6 m 2 in a pen with access to an outdoor area ( 37 ) and the available space for piglets protected from the sow varies from 0.44 m 2 ( 62 ) to 2.25 m 2 ( 37 ).…”