Environmentally enriched housing conditions affect pig welfare, immune system and gut microbiota in early life

Abstract

Background Conventional pig housing and management conditions are associated with gastrointestinal pathophysiology and disease susceptibility in early life. Developing new strategies to reduce both therapeutic and prophylactic antibiotic use is urgent for the sustainable swine production globally. To this end, housing methodology providing effective environmental enrichment could be a promising alternative approach to reduce antibiotic usage, as it has been proven to positively influence pig welfare and immune status and reduce susceptibility to infections. It is, however, poorly understood how this enriched housing affects systemic and local pulmonary immune status and gut microbiota colonization during early life. In the present study, we compared the effects of two housing conditions, i.e., conventional housing: (CH) versus enriched housing (EH), on immune status and gut microbiota from birth until 61 days of age. Results The expected benefits of enrichment on pig welfare were confirmed as EH pigs showed more positive behaviour, less aggression behaviour during the weaning transition and better human animal relation during the post weaning phase. Regarding the pigs’ immune status, EH pigs had higher values of haemoglobin and mean corpuscular volume in haematological profiles and higher percentages of T cells and cytotoxic T cells in peripheral blood. Furthermore, EH pigs showed higher ex vivo secretion of IL1ß and TNF-α after lipopolysaccharide stimulation of whole blood than CH pigs. The structure of the developing faecal microbiota of CH and EH pigs significantly differed as early as day 12 with an increase in the relative abundance of several bacterial groups known to be involved in the production of short chain fatty acids, such as Prevotella_2, Christensenellaceae_R_7_group and Ruminococcus gauvreauii group. Furthermore, the main difference between both housing conditions post weaning was that on day 61, CH pigs had significantly larger inter-individual variation of ileal and colonic microbiota than EH pigs. In addition to housing, other intrinsic factors (e.g., sex) were associated with gut microbiota development and immune competence. Conclusions In addition to the known welfare benefits for pigs, environmentally enriched housing also positively drives important aspects of the development of the immune system and the establishment of gut microbiota in early life. Consequently, EH may contribute to increasing productivity of pigs and reducing antibiotic use.

Cecal Microbiota of Free-Range Hens Varied With Different Rearing Enrichments and Ranging Patterns

“…Alternatively, or in combination with external bacterial variation, there may have been an interplay between the behavior of the pullets and the colonization process for their microbial communities. Recent evidence from pigs, reported that enriched housing affected microbiota colonization relative to standard control housing (Wen et al, 2021), although this effect was not confirmed across other research (Saladrigas-García et al, 2021). The inclusion of enrichment in the pens resulted in some variation across the rearing period in exhibited behaviors (Campbell et al, 2022), responses to fear tests (Campbell et al, 2021), and body weight (Campbell et al, 2020c).…”

Linking Animal Welfare and Antibiotic Use in Pig Farming—A Review

“…In growing pigs, the supply of manipulable materials can aid in reducing the incidence of tail biting [ 37 , 131 , 132 ]. Recent work showed that environmental enriched housing could have positive effects on the development of the immune system and the establishment of gut microbiota in early life [ 133 ]. Enabling sows to build a nest and offering straw during farrowing and lactation can prevent skin and claw lesions in piglets [ 134 ], increase activity, and reduce abnormal behaviour in the sows [ 135 ].…”

Farm characteristics affecting antibiotic consumption in pig farms in England

“…Straw, or other organic materials, may also have a beneficial effect by manipulating the development of the gut microbiota and their influence on immune competence, potentially reducing the need for antibiotics [ 34 ]. Microbiota composition can regulate the digestion and absorption of nutrients, and resistance to pathogen colonisation [ 35 ].…”

“…Other organic enrichment products may potentially elicit a similar response, although further experiments would be required for confirmation. A recent study using straw, moist peat, wood shavings, jute bags, and branches of a broom as environmental enrichment found that this enrichment positively drives important aspects of the development of the immune system and the establishment of gut microbiota in early life [ 34 ].…”