Problemas locomotores em frangos de corte em sistemas de produção

Abstract

The aim of this study was to evaluate the gait score and spondylolisthesis incidences, as well as the surface temperature of broiler breast created in re-build litter in two types of negative pressure facilities (dark house and tunnel). The experiment was conducted in two commercial broiler houses in Itaquiraí – MS county in may and june. The birds were housed in mixed batches in litter rebuild (seven uses) made by shavings wood, with birds density of 14 birds m-2. The study evaluated the thermal environment conditions, the litter quality, the gait score of birds, the surface temperature of the breast and spondylolisthesis at birds with 42 days old. The analysis of the thermal environment conditions (temperature and relative humidity) and the litter quality was performed by completely randomized design with two facilities: dark house and tunnel x 12 repetitions. The analysis of the surface temperature of the birds’ breast and the gait score were performed by completely randomized design in double factorial 2x2 (two facilities - dark house and tunnel x sex - male and female) with 24 repetitions. In order to verify that the ventilation system type and sex are associated with the occurrence of injuries in birds in the last building phase were analyzed by logistic regression: odds ratio and risk ratio. The mean comparisons were performed by Tukey test with 5% level of significance, and 95% confidence for the injury incidence in birds (gait score and spondylolisthesis). The values of thermal environment were higher in tunnel ventilation facility (p <0.05). The thermal conditions showed similar in the both facilities (p> 0.05), while the litter pH was most basic for the dark house (p <0.05). Tunnel ventilation facility presented interaction between the sex of birds and locomotor disability (p <0.05). The surface temperature of the breast of the birds was higher in dark house facility (p <0.05). There is a strong association between sex of birds and locomotor disability type in the tunnel ventilation system. The results of Odds Ratio and Risk Ratio indicated that there is no association with sex of birds or type of facilities (p> 0.05). The thermal environment and the litter quality presents higher average air temperature and litter pH for the system type tunnel. In short, the facilities type and sex affected the walking ability of birds.