Desempenho de frangos de corte alimentados com dois níveis de vitamina D e alojados sobre dois tipos de cama.

Abstract

Two experiments were carried out with the objective of evaluating the performance, meat quality and incidence of pododermatitis lesions and behavior of broilers fed with vitamin D3 levels raised on two types of litter. In experiments I and II, 160 one-day-old male broiler chicks of the Cobb 500® strain were used. At eight days of age, the birds were homogenized and the treatments distributed in a completely randomized design (DIC), in a 2x2 factorial arrangement, two levels of vitamin D3 (100% and 200% of the requirement of Rostagno et al.(2017)) and two types of litter (shavings and rice straw), with four treatments (100% of the vitamin D requirement and shavings bedding, 200% of the vitamin D requirement and shavings bedding, 100% of the vitamin D requirement and rice straw 200% of the vitamin D requirement and rice straw litter. ) and five replications with 24 kg/m2. In experiment I, feed intake, weight gain, feed conversion, carcass yield, prime cuts yield (thigh, drumstick and breast), relative weights of edible viscera (heart, liver and gizzard), immune organs (Bursa of Fabricius and Spleen), weight and length of the small intestine, abdominal fat, breast meat color (L* = lightness, a* = red, b* = yellow), pH, weight loss by thawing, weight loss by cooking and shear force. In experiment II, the maximum and minimum surface temperatures and the thermal amplitude of the foot pad, the values of humidity, pH and bed temperature, behavioral assessment at 35 and 41 and the visual score of the foot pad at 42 were evaluated. days old. In experiment I, it was observed that vitamin levels and types of bedding did not influence (P>0.05) feed intake, feed conversion and body weight. Weight gain was not influenced (P>0.05) by the vitamin, but there was an effect of bedding (P<0.0263). There was an interaction between vitamin and litter for (P<0.0143) feed intake and weight gain (P<0.0027). Vitamin D levels and types of litter did not affect carcass, breast, thigh and drumstick yields, relative weights of edible viscera, immune organs, weight and length of the small intestine. There was an interaction between vitamin D3 levels and types of bedding for luminosity (p>0.0292). It was observed that vitamin D levels and types of litter did not influence (p>0.05) red content (a*), yellow content (b*) and pH. In experiment II, minimum temperature and thermal amplitude were not influenced by vitamin D3 levels and types of bedding. There was an interaction between vitamin D3 levels and types of litter for maximum temperature and pH. Moisture was influenced by vitamin D3 levels and materials used as bedding. The pH was influenced by bedding materials. Bed temperatures were not influenced by vitamin D3 levels and bedding materials. The different levels of vitamin D3 and the types of bedding influenced the visual score of the footpad, behavioral scores eating, drinking, investigating pity, standing and panting. It is concluded that the level of 200% of vitamin D3 and shavings litter provided the best performances for broilers and that thermography, visual evaluation were efficient to show that pododermatitis was in the initial phase.