Response of lactating cows to the total replacement of corn by citrus pulp and to the supplementation of organic trace minerals II: performance and savings

The performance and financial efficiency of dairy cows fed diets formulated by total replacement of corn by citrus pulp was evaluated. Treatments with corn contained 10% corn and 24% citrus pulp while citrus diets contained 33% citrus pulp. The complete replacement of inorganic sources of Cu, Mn, Se, Zn, and Cr by organic sources was simultaneously evaluated. The four diets generated by the factorial arrangement of the two factors were fed to 16 cows in 4x4 Latin Squares. Means of milk production were 27.5kg and 28.4kg for cows fed citrus pulp and corn (P=0.04) diets, respectively. The complete replacement of corn by citrus pulp decreased milk protein production and content (P<0.03) and had no effect on milk fat (P>0.24). Diets formulated exclusively with citrus pulp may be recommended when milk payment is based exclusively on volume, but the inclusion of corn may increase income over feed cost when milk solids are valued.

bovine; starch; milk production; feed cost