The objective of this research was to evaluate the effects of environmental enrichment on the welfare of industrial broiler chickens. Four hundred male broilers, from one to 38 days, were equally distributed in 20 pens of 2m2, being 10 pens controlled no-enriched boxes (CE) and 10 in environment enriched (EE) with perches, sand tray, cabbage, kale and hanging objects. At 7, 21 and 35 days birds were individually scored for lameness, valgus-varus deviation and foot pad dermatitis (health indicators). Blood was collected form hematological analyses. At week one, two and six, in two boxes/treatment, behavior was assessed during 13 hours per day, using the scanning method, every 20min. Average consumption, weight gain and feed conversion (performance indicators) of broilers were weekly assessed. Hematologic and performance results were compared by F test, behavior and health indicators by Chi square and mortality by T test. There was no difference between enriched and no-enriched boxes for health indicators. There was no difference for the heterophil:lymphocyte ratio (CE 0.47±0.02/EE 0.45±0.02), but the basophil count was higher than normal values in both treatments (1338±97 µL-1; 1212±106 µL-1). There was a decrease in squatting (35.0%/31.8%) and sleeping (14.6%/13.1%) behaviors and increases in dust-bathing (0.9%/1.5%), pecking objects (0.2%/0.6%), body maintenance (12.7%/14.2%) and foraging (8.2%/12.0%) for enriched boxes. No significant difference in mortality (2.5%/4.0%) and performance were found. The enriched boxes showed benefits on chicken's behavior, however, health problems affected negatively the welfare of broiler chickens in enriched and no-enriched treatments.
behavior; contact dermatitis; heterophil:lymphocyte; performance.
