Caracterização de diferentes tipos de cama de frango de corte com inclusão de gramínea desidratada e sua influência na produção

Abstract

The litter is important for poultry and its quality raises concern in production, as it affects performance, health, carcass quality and the welfare of chickens. In Brazil the material most used for this purpose is wood shavings, followed by rice husks, but the use of these materials has been limited by market competition and availability, and using grass clippings waste as a litter in poultry would contribute sustainably to the environment. In this context, the present study was carried aiming to evaluate the effects of different types of bedding materials with inclusion of dehydrated grass, on the carcass yield and performance, and to verify the physical- chemical and microbiological characteristics of the materials used. 1080 male day-old broiler chicks of the Cobb 500® strain were used, distributed in a completely randomized design, in a 3x2 factorial arrangement (levels of dehydrated grass (0, 25 and 50%) and bedding materials (bark rice and shavings)), with six repetitions, totaling 36 boxes, with 30 chickens each. The performance of the poultry was analyzed until 42 days of age when the broiler were slaughtered and the measurements of carcass and cuts yield. Regarding to litter variables, physical and chemical characteristics and the total microorganism count were analyzed. The poultry' surface temperature was also evaluated. The inclusion of grass showed greater microbiological contamination in the initial phase, stabilizing with the other materials after 28 days. The highest average of internal temperature was in litter with rice husk (P=0.0383), which also showed greater water retention capacity (P <0.0001). Inclusions above 25% of grass have higher humidity (P <0.0001), water holding capacity (P=0.0018), pH (P<0.0001) and nitrogen content (P=0.0024); and lower density (P<0.0001) and FDA (P<0.0001 0 days and P=0.0012 with 42 days) in its structure. The highest emissions occurred when including 25% grass (P=0.0213). The inclusion of dehydrated grass did not affect zootechnical indexes and carcass yield (P<0.0001), favoring feed conversion in the initial stages (P=0.0119). The inclusion of grass can be used to replace up to 25% in shavings, without harming the physical-chemical parameters of the materials and performance of the poultry.