Dietary roughage sources affect lactating Holstein x Zebu cows under experimental conditions in Brazil: a meta-analysis

摘要: To reduce costs, lactating cows are often fed a higher proportion of roughage and alternative feeds; however, such protocols may not lead to optimal milk production. Using meta-analysis, we evaluated the effects dietary sources on composition, voluntary intake, digestibility diets crossbred Holstein x Zebu under experimental feeding conditions in Brazil. Finally, assessed yield composition. The database was composed 43 experiments with 183 treatments, including 943 cows. data were obtained from studies published between January 2000 December 2015. by analysis variance, considering distribution variables. differed dry matter crude protein (CP) contents according sources. Diets based corn silage demonstrated intakes neutral detergent fiber (NDF), CP, total digestible nutrients, which improved NDF resulted compared one source or those combination two present study that compromised production produced yields when silage.