Effect of stocking density on performance, infection by Eimeria spp., intestinal lesions and foot pad injuries in broilers with outdoor access under tropical conditions

1. The study was carried out to evaluate the effect of stocking density on performance, litter moisture, Eimeria oocyst shedding, intestinal and foot lesions in broilers. 2. A total of 192 1-d-old male Cobb broilers were distributed with three different stocking densities (6, 8 or 10 chickens/m(2)) with outdoor access and eight replicates in a completely randomised design over two periods. Productive parameters were measured from 3 to 7 weeks of age. 3. Oocyst counts (OPG) in both excreta and litter were performed at 3, 4 and 5 weeks of age. Intestinal and foot pad lesions were evaluated at 7 weeks old. The stocking density of 6 birds/m(2) had the highest body weights (P < 0.05) (2129 +/- 37.67, 2759 +/- 50.82 and 3167 +/- 75.64 g at weeks 5, 6 and 7 of age, respectively). 4. Feed intake decreased with increasing stocking density at week 3 (r = -0.57), 4 (r = -0.48), 5 (r = -0.84), 6 (r = -0.68) and 7 (r = -0.65) of age (P < 0.05). Birds with stocking densities of 8 and 10/m(2) consumed, respectively, up to 11% and 19.5% less feed than the lower stocking density groups. 5. Stocking density affected (P < 0.05) feed conversion (1.61, 1.49 and 1.46) and litter moisture (40.88, 52.60 and 56.19%) at 3 weeks of age. Neither carcase yield nor mortality was different between densities (P > 0.05). Likewise, there was no effect of stocking density on OPG neither in excreta nor in litter, intestinal lesions, or foot pad and hock injuries (P > 0.05). 6. In conclusion, the higher stocking density decreased both the feed intake and the live weight in broilers, but there were no effects in the number of Eimeria OPG in excreta or litter, neither intestinal lesions nor in foot pad injuries.