Mechanical vibrations present in transporting live loads can impair physiologic stability and the future performance of livestock. The aim of this study was to evaluate, using simulations, the effect of two levels of vibration (9.64 and 15.19 m s-2) in stress responses and performance of day-old chicken. The vibrations were simulated by means of a shaking machine and studied by general acceleration values. The simulation period lasted two hours for each treatment and the birds had their parameters (difference in weight, respiratory rate, and performance in the first week) compared to control groups (without vibration). The experiment was conducted in a randomized design and the results showed that these levels did not differ significantly (p < 0.05) in weight and performance in the first week of life. However, chicks subjected to acceleration of 15.19 m s-2 achieved a significant increase (p < 0.05) in respiratory rate (54.33 mov min-1), thus concluding that the vibrations may act as a potential stressor during transport of these birds.
poultry production; acceleration; respiratory frequency
