Impact of structural and cognitive enrichment on the learning performance, behavior and physiology of dwarf goats (Capra aegagrus hircus)

• We evaluated the impact of structural and cognitive enrichment in dwarf goats.
• Structural enrichment improves learning performance in visual-discrimination tasks.
• Structural enrichment increases locomotor activity in the OF/NO-test.
• Cognitive enrichment leads to enhanced curiosity toward unknown objects.
• Enrichment has no impact on the level of saliva cortisol under challenge.

Intensive husbandry usually offers only limited opportunities for animals to perform their characteristic species–specific behavior and can lead to boredom, stress or frustration. The positive impact of structural forms of environmental enrichment on animal welfare is well investigated because it is relatively low-cost and quickly performed. In contrast, approaches that integrated cognitive enrichment into the housing of animals are hardly investigated. The present study assessed the impact of structural and cognitive enrichment on learning as well as on the behavioral and physiological responses of 34 female dwarf goats (Capra aegagrus hircus) using a 2 × 2 factorial design. After weaning at the age of 5 weeks, the animals were randomly allocated to four groups (8–9 goats per group). Two of the animal groups were housed under conditions of structural enrichment; the other two groups under barren housing conditions. One group, respectively, obtained drinking water at a normal water bowl, the other obtained drinking water as a reward for a correct choice at a learning device, which was integrated into the housing pen and presented automatically visual four-choice discrimination tasks. Before the first and after each of three different learning tasks, the reactions of the animals to external challenges in a combined open-field/novel-object test were recorded. An enriched environment was shown to positively affect the learning performance of the goats. Structural enrichment of the housing conditions increased the motor activity of the animals in the external test situation, whereas cognitive enrichment lead to enhanced curiosity toward and prolonged contact with the unknown object. However, there were no differences in stress levels, which were measured through salivary cortisol, between any of the groups. We conclude that the combination of structural and cognitive enrichment in particular can improve the behavioral competence of dwarf goats in challenging situations and may have beneficial effects for their welfare.