Concentrate intake and performance of dairy calves subjected to programs of supplementary lighting

摘要

This research aimed to assess Girolando calvesa?? concentrate intake and performance when placed in shelters with distinct roofing materials and programs of supplementary lighting during the milk-feeding stage. In order to so, we used a completely randomized design with a 3??3 factorial arrangement, with three replications. Females Girolando calves (n=27) were assigned in individual shelters at random with 3 different roofing materials (fiber cement tile, recycled tile and thatched roofs) and subjected to three lighting programs (12, 16 and 20 hours). No interaction was observed between roofing material and lighting programs, whilst no significant effect (P>0.05) was observed among the roofing materials. The supplementary lighting, by providing greater light exposure time, has stimulated intake and therefore, significantly affected (P<0.05) the concentrate intake and performance of the animals that were subjected to 20 hours of light.