Lesões no coxim plantar de frangos de corte em diferentes sistemas de produção

Abstract

The pododermatite is a locomotor disease. This problem is characterized by necrotic lesions on the chickens’ feet and affects animal welfare and the quality of this product. The aim of this research was to evaluate the incidence of lesions in the footpad of broiler on different ages and two broiler houses with tunnel ventilation system. The evaluated was made by infrared thermography, litter quality (humidity, pH and temperature) and environmental conditions (temperature and relative humidity) of the facility. The statistic analysis was made by completely randomized design to the litter quality using double factorial 2x4 (2 broiler house - dark house and tunnel and 4 birds’ ages - 21, 28, 35 and 42 days old) with 12 repetitions, totaling 96 experimental samples. The same design was used to thermal conditions by double factorial 2x4 (2 broiler house - dark house and tunnel and 4 birds’ ages - 21, 28, 35 and 42 days old) with 4 repetitions, totaling 32 experimental samples. The statistic analysis of superficial temperature of footpad was completely randomized in a double factorial 2x2 (2 broiler house - dark house and tunnel and 2 sex – male and female) with 15 repetitions. The footpad analysis was calculated by the incidence of lesions on footpad in order to evaluated the probability, risk ratio and odds ratio using Fisher Exact Test when the birds present: 21, 28, 35 and 42 days old. Tukey test was used to mean comparisons between factors (5% of significance level). Birds with 28 days old reared in dark house presented higher surface temperatures on footpad of right leg (mean = 31.20°C) than the birds reared in tunnel systems (mean= 30.24°C). Likewise, the left leg present superficial temperature of footpad higher in dark house (31.68 °C) than the tunnel systems (30.11 °C). At 35 days old of birds, the surface temperature mean of superficial temperature of bird’s footpad reared in dark house system presents the lower left cushion (29.48 ° C) compared to the birds of the tunnel system (30.56 °C). At 42 days old of birds, the male birds presents footpad surface temperatures (34.52 °C) higher than females (32.49 °C) in dark house system. It was significant the mean of right (male = 33.61 °C and female= 32.44 ° C) and left footpad surface temperature (male = 33.95 °C and female = 32.80 °C) at 42 days old of birds. There is an association between the incidence of footpad dermatitis and surface temperature of footpad. This association features a consequence of injury in facilities with tunnel ventilation system and the male birds.