Effect of enriched housing on welfare, production performance and meat quality in finishing lambs: The use of feeder ramps

•Pen enrichment improves the adaptation of the lambs to a novel environment.•Pen enrichment optimises lamb welfare and productive performance.•Lambs from enriched pens showed a higher average daily gain with heavier carcasses.•Lambs from enriched pens showed improved pHult, meat colour and texture.•Lambs fattened in barren environments showed chronic stress and immune suppression.

This study analyses the effect of environmental enrichment on the welfare, productive traits and meat quality of lambs housed in feedlots. Sixty lambs were placed in enriched (EE) or conventional (CO) pens (3 pens for each treatment, 10 lambs/pen) where EE had a wooden platform with ramps that provided access to a concentrate hopper, cereal straw as bedding and forage, and one play ramp. The CO pen was barren, similar to commercial feedlots. The physiological adaptation response of EE lambs was more efficient than CO, since the latter mobilised more body reserves (i.e., increased NEFA, P < 0.05), and had lower levels of immunity (i.e., increased N/L, P < 0.05), which indicate chronic stress, probably associated with the barren environment. The EE lambs had a higher (P < 0.05) average daily gain, with heavier carcasses and higher fattening scores, as well as lower pHult, higher L* and b* values, and lower values of texture (P < 0.05).