Compressed Brown Algae as a Potential Environmental Enrichment Material in Growing Pigs

Abstract

In barren housing conditions, enrichment materials are given to pigs to improve their welfare. Here, we assessed the suitability of an algae-based cylinder as an enrichment material on the behavioral, physiological, health and productivity welfare indicators of pigs. Algae was compared with metal chains and wood logs. The study involved 444 pigs from two successive batches on one single farm. During the suckling period, half of the pigs received algae and the control pigs received no material. After weaning and until the end of fattening, algae, wood or chains were equally distributed among the pigs. Consumption of algae cylinders was different between pens and between batches. After weaning and during the fattening period, although the results differed between batches, no significant difference was observed in the object manipulations. Salivary cortisol, used as biomarker to measure the stress levels after pig transfers, were similar between the treatments. Enrichment material made from algae had no negative effect on pig health and no effect on performance and body condition. Regarding their characteristics and according to Commission Recommendation (EU) 2016/336 classification, algae cylinders can be categorized as suboptimal enrichment materials, although the present results suggest that it does not significantly improve pig welfare compared to a metal chain, which is categorized as a material of marginal interest.

Consequences of timing of organic enrichment provision on pig performance, health and stress resilience after weaning and regrouping

“…Our results on weaner FCR are consistent with the findings of Beattie et al, 2000 , van de Weerd et al, 2006 . However, they contrast the results of other studies which did not find any significant effect of edible enrichment on FCR ( Ruiterkamp, 1987 , Lyons et al, 1995 , Peeters et al, 2006 , Munsterhjelm et al, 2009 , Averós et al, 2010 , Nannoni et al, 2016 , Nannoni et al, 2018 , Ipema et al, 2021 , Pol et al, 2021 ). Organic enrichment has been found to have positive effects on pig gut microbiota, which in turn affects the way feed is utilised ( Wen et al, 2021 ).…”

“…However, this is not consistent either with our results on decreased ear lesions in E weaners or with the results of Ko et al 2020 who found that pigs provided with enrichment toys had decreased salivary amylase concentrations on day 1 and 2 postweaning, and decreased cortisol concentrations on day 2 ( Ko et al, 2020 ). Pol et al (2021) did not find any difference between S pigs and pigs which were provided with compressed algae on salivary cortisol concentrations postweaning, and Nannoni et al (2018) did not find any significant differences in hair cortisol concentrations of pigs provided with a chain, wooden logs, or a vegetable edible block. However, sawdust, natural hemp ropes, and rubber balls were found to decrease hair cortisol concentrations in pigs ( Casal et al, 2017 ).…”

“…A number of studies report positive effects of edible enrichment on feed intake ( Ruiterkamp, 1987 , Lyons et al, 1995 , Beattie et al, 2000 , van de Weerd et al, 2006 , Munsterhjelm et al, 2009 , Luo et al, 2020b ), while others have not found any effects ( Peeters et al, 2006 , Averós et al, 2010 , Nannoni et al, 2016 , Nannoni et al, 2018 , Fàbrega et al, 2019 , Chou et al, 2020 , Pol et al, 2021 ). Our ADFI results are consistent with the findings of Beattie et al (2001) , who also found decreased feed intake in E pigs.…”

“…The expected effects of enrichment on body lesions are also inconclusive. Some studies have found positive effect of a higher enrichment on body lesions ( Lyons et al, 1995 , Guy et al, 2002 , Bulens et al, 2018 , Lingling et al, 2018 , Fàbrega et al, 2019 , Wen et al, 2021 ), whereas others do not report a significant effect ( van de Weerd et al, 2005 , Peeters et al, 2006 , Scott et al, 2006 , van de Weerd et al, 2006 , Munsterhjelm et al, 2009 , Vanheukelom et al, 2011 , Yang et al, 2018 , Fàbrega et al, 2019 , Pol et al, 2021 ), or have even found a negative effect ( Munsterhjelm et al, 2009 , Melotti et al, 2011 , Bulens et al, 2016 , Fàbrega et al, 2019 , Wen et al, 2021 ). Because almost all these studies provided pigs with rooting substrates, we do not know why the results are inconclusive, but the reason might be again the differences in the methodological approaches.…”

Investigating risk factors behind piglet facial and sow teat lesions through a literature review and a survey on teeth reduction

“…In Lewis et al (64), all piglets could access the shredded paper provided as enrichment at the same time (as it could be removed from a box), but only a limited number of piglets could access the rope at any one time. In a study by Pol et al (101), an algae cylinder provided during the suckling period did not affect lesion scores (although lesion scores only included an ear assessment). The study found that overall, this type of object was of marginal enrichment interest to the pigs, similar to a non-effective metal chain (102).…”