The Role of Environmental Enrichment in Improving Welfare and Zootechnical Performance in Pigs

Introduction

Animal welfare in the context of intensive pig production has ceased to be solely an ethical or regulatory concept, becoming instead a decisive factor for zootechnical performance and production sustainability.

From a physiological and ethological perspective, chronic stress and housing conditions that restrict the expression of natural behaviors alter the hypothalamic–pituitary–adrenal axis, with immunosuppressive, digestive, and metabolic consequences. These dysfunctions translate into poorer average daily gain (ADG), greater batch heterogeneity, increased lesions, higher susceptibility to disease, and consequently, more intensive use of antimicrobials.

A multifactorial approach to animal welfare requires interventions that directly impact behavior, environment, and physiology on pig farms.

In this context, environmental enrichment through manipulable materials or toys represents an effective, evidence-based strategy to improve animal comfort, prevent abnormal behaviors such as tail biting, and stabilize social hierarchy in housed groups.

Research studies and field trials support that appropriate oral and sensory stimulation reduces stress expression and improves key productive markers across all production phases.

The current regulatory framework, particularly Royal Decree 159/2023 governing housing and management conditions, as well as IAWS and WELFAIR® certification protocols, strengthens the need to implement effective, durable, safe, and stage-appropriate enrichment systems.

In this regard, companies such as Porcsavi, specialized in animal welfare and biosecurity solutions for the swine sector, have developed in collaboration with AMBiotec a range of enriched toys designed not only to promote natural behaviors but also to provide physiological functionality. By incorporating natural ingredients, plant extracts, and high-quality bioactive compounds, these devices act as environmental nutraceuticals, delivering beneficial effects on digestive health, gut microbiota, and animal immunocompetence.

Foundations of Environmental Enrichment in Pigs

Pig Ethology and Exploratory Needs

The domestic pig (Sus scrofa domesticus), as a highly exploratory and intelligent species, innately exhibits a need to interact with its environment through behaviors such as rooting, chewing, sniffing, and manipulating objects. These activities not only satisfy behavioral needs but also promote neuroplasticity, emotional stability, and social cohesion within the group. The absence of adequate stimuli leads to behavioral deviations characterized by stereotypies, aggression, tail biting, and other signs of discomfort that negatively impact productivity.

Functional Requirements of Enrichment Materials

To be considered effective, enrichment materials must meet a series of properties established by technical bodies such as EFSA, as well as Spanish sectoral guidelines.

These requirements include:

• Manipulability: the ability to be moved, pushed, chewed, or deformed by the animal.
• Investigability: olfactory, gustatory, or tactile stimulation that sustains animal interest.
• Safe composition: no risk of toxicity, hazardous fragmentation, or obstructive ingestion.
• Adequate durability: mechanical resistance adapted to the activity level of the animal, without premature loss of stimulation.
• Innovation and rotation: design that allows sensory novelty and prevents habituation.

Materials may be edible (pressed blocks, vegetable ropes), semi-hard (soft woods), or mobile (balls, chains), and their combination optimizes positive effects on behavior and performance.

Application Across Production Phases

Post-weaning piglets

Weaning is one of the most vulnerable stages of the cycle due to the convergence of stressors: maternal separation, dietary change, social reorganization, and exposure to new pathogens. The use of enriched toys at this stage has been shown to:

• Reduce vocalizations and signs of anxiety.
• Increase early intake of solid feed.
• Improve average daily gain in the first weeks.
• Lower incidence of post-weaning diarrhea.

A relevant advancement in this context is the incorporation, in toys developed by Porcsavi in collaboration with AMBiotec, of a phytobiotic core to enhance animal health. This core is composed of essential oils and plant-derived active compounds selected for their antioxidant, anti-inflammatory, and digestive effects, which contribute to maintaining a balanced gut microbiota and a functional mucosal barrier. Thus, the toy acts as a “behavioral and nutraceutical vector”, simultaneously supporting natural behavior and gastrointestinal health.
With group size-adapted presentations, this solution represents a comprehensive support against the challenges of weaning, aligned with antimicrobial reduction strategies.

Fattening Phase

During fattening, groups present a higher risk of tail biting, especially when tails are not docked. Environmental enrichment at this stage has proven effects:

• Reduced aggression and bite-related lesions on farms.
• Fewer treatments for secondary infections.
• Improved batch homogeneity.
• Increased feed efficiency.

Porcsavi’s toys for this phase are formulated with natural compounds that induce relaxation and stimulate sustained oral manipulation, improving animal health and maintaining interest for 6–8 weeks. In addition, their design prevents premature deterioration, allowing continuous use without frequent replacements, optimizing the cost/benefit ratio.

Gestation and Pre-farrowing

Group housing of pregnant sows requires special welfare attention, as episodes of aggression negatively affect embryo implantation and increase litter variability. Environmental enrichment during gestation helps improve animal health through:

• Reduction of hierarchical conflicts.
• Improved emotional stability.
• Fewer skin lesions and lameness.
• Better reproductive parameters (successful farrowings, liveborn piglets).

The enriched products developed for this phase integrate ingredients with relaxing effects and sensory attractants that capture sow attention and redirect exploratory behavior away from the flanks of pen mates.

Lactation and Postpartum

The peripartum period is critical for maternal and neonatal welfare. Positive stimuli during this period promote maternal behavior, colostrum intake, and piglet survival. Enrichment devices for this stage:

• Reduce sow stress and abrupt movements.
• Stimulate maternal–offspring bonding.
• Increase piglet effective resting time.
• Support postpartum recovery.

In this case, Porcsavi has developed specific toys with aromas and flavors that encourage attention towards piglets, improve positive interaction with the environment, and foster a more stable lactation environment.

Impact on Productive Parameters

Proper implementation of environmental enrichment has shown positive effects on multiple productive indicators. Under both controlled and commercial conditions, improvements have been documented such as:

Furthermore, enrichment reduces variability between individuals, resulting in more homogeneous and predictable batches, with improved slaughter planning.

Regulatory Compliance and Sustainability

The implementation of environmental enrichment is not only a technical recommendation but a progressively mandatory requirement, with full enforcement in March 2026 according to Royal Decree 159/2023. Certification audits (WELFAIR®, IAWS) already specifically assess the presence, type, functionality, and maintenance of enrichment materials within the production system.

The choice of scientifically based, production stage-adapted materials, such as those developed by Porcsavi and AMBiotec, facilitates legal compliance, minimizes operating costs, and enhances consumer perception of the final product.

Conclusion

Environmental enrichment in pigs is a strategic tool that aligns productivity, sustainability, and animal welfare. Beyond fulfilling an ethological role, functional and nutraceutical toys provide tangible physiological benefits, with repercussions on digestive health, social behavior, and zootechnical performance.

The innovation developed by companies such as Porcsavi, in collaboration with AMBiotec, exemplifies how the design of products based on natural compounds can offer comprehensive solutions to the current challenges of intensive pig farming.