Effect of including double bunks and straw on behaviour, stress response production performance and meat quality in feedlot lambs

• Double bunks and straw were added in pens of indoor feedlot lambs.
• We evaluated the effect on behavior, stress physiology, performance and meat quality.
• Enriched lambs (ED) showed higher preference for enrichments and fewer stereotypies.
• ED had higher levels of immunity, but they also increased their reactive response.
• Enriched system had no detrimental effects on meat products but may difficult the handling.

The development of proper environmental enrichment would be a useful tool to tackle the welfare problems associated with intensive indoor lamb production. This study analyses the effect of enrichment with double bunk and cereal straw on behaviour, use of space, stress response, productive traits and meat quality variables during the finishing phase of fattening lambs. Sixty lambs were placed in enriched (ED) or conventional (CO) pens (3 pens each treatment, 10 lambs/pen) where ED had a double bunk with ramps and cereal straw as bedding and forage. The CO pen was barren, similar to commercial feedlots, without straw or any other enrichment. The proposed ED had a positive effect on the behavioural characteristics of the lambs, which displayed a richer behavioural repertoire, fewer stereotypes and more affiliative interactions, improving group cohesion. Moreover, ED lambs had enhanced immunity and there were no discernible detrimental effects on performance or on the commercial quality of their meat. However, the enriched system proposed may pose difficulties for feedlot handling procedures.