A multi-suckling system combined with an enriched housing environment during the growing period promotes resilience to various challenges in pigs

Abstract

Little is known about the impact of social and environmental enrichment on improving livestock resilience, i.e. the ability to quickly recover from perturbations. We evaluated the effect of an alternative housing system (AHS) on resilience of pigs, as compared to conventional housing (CONV). The AHS consisted of multi-litter housing during lactation, delayed weaning, extra space allowance and environmental enrichment at all times. We assessed recovery to a 2 h-transport challenge, an LPS injection, 2 h-heat stress and a biopsy wound in 96 pigs. Additionally, indicators of long-term “wear and tear” on the body were determined. AHS pigs had better physiological recoveries with quicker returns to baseline in the transport and LPS challenges, showed lower cortisol accumulation in hairs and lower variance in weight gain over the experimental period compared to conventionally-housed (CONV) pigs. They also had higher levels of natural antibodies binding KLH than CONV pigs. Their response to heat stress revealed a different strategy compared to CONV pigs. Taken together, AHS pigs appear to be more resilient and experience less chronic stress. Enhancing welfare by provision of social and environmental enrichment that better meets the behavioural needs of pigs seems to be a promising approach to improve their resilience.

Effects of a Multi-Suckling System Combined With Enriched Housing Post-Weaning on Response and Cognitive Resilience to Isolation

“…Although favourable effects of such housing conditions on pig behaviour are widely reported, information about their impact on resilience is scarce. Recent studies indicate, however, that pigs housed in enriched environments are more resilient to disease, sickness, and transport challenges, as shown in a faster recovery and/or lower signs of accumulated stress ( 25 , 26 ).…”

“…Depending on the resilience status of animals, either a mild stressor (e.g., a few hours of isolation) for non-resilient individuals or a more severe stressor for resilient individuals may disrupt their cognitive functioning and result in inappropriate responses with negative repercussions for the individual or its pen mates. Housing conditions may influence the development of cognitive functions and modulate the general resilience of the individuals and their welfare ( 26 , 35 ). Therefore, providing social and environmental enrichments is expected to have beneficial effects on both social isolation stress and cognitive resilience, although this has not been investigated yet.…”

Estimation of Resilience Parameters Following LPS Injection Based on Activity Measured With Computer Vision

“…A total of 144 Topigs-20 x Tempo pigs (n = 71 females; n = 73 males) divided over three batches (n = 48 pigs per batch) were used [same animals as (Parois et al, 2022)]. Half of the pigs originated from a conventional farrowing pen (CONV) and the other half from an alternative group housing system (AHS) at the Swine Innovation Centre (Sterksel, The Netherlands).…”

“…Sickness behavior involves deviations from the diurnal activity rhythm (Moya et al, 2008;Nordgreen et al, 2018;Munsterhjelm et al, 2019;Veit et al, 2021;Parois et al, 2022). An LPS challenge is a suitable sickness model to verify whether a computer vision tracking algorithm is able to detect potential deviations from a diurnal activity rhythm in a controlled and measurable manner.…”

“…An LPS challenge is a suitable sickness model to verify whether a computer vision tracking algorithm is able to detect potential deviations from a diurnal activity rhythm in a controlled and measurable manner. Most studies using an LPS challenge in pigs observe the animals for 24 hours or less (Johnson and Von Borell, 1994;Moya et al, 2006;Parois et al, 2022). However, Munsterhjelm et al (2019) observed a change in social behavior even 40 hours after physiological signs of sickness had dissipated.…”