Assessment of probiotic supplementation on growth performance and gut microbiota in weaned piglets across different housing systems

Project Abstract

Probiotic supplementation was evaluated for its effects on growth performance and gut microbiota in weaned piglets reared under diverse housing systems to determine whether housing environment modulates probiotic efficacy. A randomized, factorial design assigned piglets (n = 360) within two genotypes and two sex categories to four housing systems (conventional farrowing-to-weaning pens, enriched floor pens, group-housed pens with environmental enrichment, and tethered stalls) combined with two dietary treatments (basal diet vs. basal diet plus a multi-strain probiotic at recommended inclusion rate). The study spanned from weaning (21 days) to 8 weeks post-weaning, with daily feed intake recorded, weekly weight gain measured, and feed conversion ratio calculated. Fecal samples were collected at weaning, mid-study, and at conclusion for 16S rRNA gene sequencing to characterize gut microbiota composition and diversity; short-chain fatty acids (SCFAs) and key metabolites were quantified using gas chromatography-mid infrared detection. Growth performance data revealed a significant interaction between housing system and probiotic supplementation on average daily gain (ADG) and feed efficiency; piglets in enriched and group-housed environments exhibited the largest improvements in ADG with probiotic administration, while conventional and tethered systems showed more modest gains. Probiotic treatment reduced the duration of post-weaning growth lag and enhanced final body weight by an average of 6–12% across most housing conditions, with the greatest benefits observed in enriched and group-housed pens. Health indicators, including incidences of diarrhea and need for medical interventions, were lower in probiotic-supplemented groups, particularly within the enriched housing context. Microbiota analyses showed probiotic-supplemented piglets had increased relative abundance of Lactobacillus and Bifidobacterium spp., and a shift toward a more diverse and stable microbial community in enriched and group-housed systems. The probiotic groups also exhibited elevated concentrations of beneficial SCFAs, notably butyrate and propionate, correlating with improved intestinal histomorphology as evidenced by increased villus height-to-crypt depth ratios in a subset of animals. In contrast, piglets in conventional and tethered housing demonstrated smaller microbiota shifts and less pronounced growth improvements, suggesting environmental stressors in these systems may attenuate probiotic efficacy. Multivariate analyses indicated that housing-related factors such as space allowance, social interactions, and environmental complexity moderated the relationship between probiotic intake and growth outcomes through microbiota-mediated pathways. Resistance to pathogen challenges and measurements of immune markers indicated a modulating effect of probiotics on mucosal immunity, with higher levels of anti-inflammatory cytokines and lower systemic inflammatory markers in probiotic-treated groups under enriched housing. The study concludes that probiotic supplementation can substantially enhance growth performance and gut health in weaned piglets, but the magnitude of benefits is contingent upon housing conditions, with enriched and socially interactive environments optimizing probiotic effectiveness through favorable microbiota modulation and metabolite production. Practical implications include tailoring probiotic strategies to housing designs to maximize production efficiency and animal welfare.

Project Overview

What This Project Is About

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A straightforward, beginner-friendly look at using probiotics to help piglets grow better and maintain a healthy gut, and how different living environments might change these effects.

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The Problem It Addresses

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Farmers want pigs that grow well with fewer health problems, but results can vary depending on housing (e.g., pens, floor types, space) and gut health. This project explores whether probiotics help piglets regardless of housing and why housing might influence outcomes.

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Objectives of the Project

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1. Understand what probiotics are and why they are used in pig farming.
2. Compare growth performance of piglets given probiotics vs. not given across different housing systems.
3. Assess gut health indicators (like gut bacteria) and link them to growth data.
4. Identify practical housing scenarios where probiotics are most effective.
5. Provide simple guidelines for farmers based on findings.

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What You Will Do Step by Step

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1. Review basic literature on probiotics and piglet growth.
2. Design a small-scale experiment with probiotic and control groups in multiple housing setups.
3. Collect growth data (weight gain, feed intake) over a set period.
4. Collect gut health data through non-invasive samples or tests.
5. Analyze data to compare effects across housing types.
6. Interpret results and discuss practical implications for farming.

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Expected Outcome

Clear understanding of whether probiotics improve growth and gut health in piglets and how housing influences these effects, leading to simple, actionable recommendations for small- to medium-scale pig farms.