Silage of residue from the extraction of cassava starch in diets from lactating holstein cows Silagem de resíduo da extração de amido da mandioca na dieta de vacas em lactação da raça holandesa

The objective of evaluating the intake and digestibility of nutrients, milk production, production efficiency and composition, and blood parameters of Holstein cows fed silage of the residue from the extraction of cassava starch (SRECS), replacing 0%, 25%, 50%, 75%, or 100% of the corn feed. Cows with average production of 35 kg of milk a day were assigned in a 5x5 Latin square design, and for the 21 days trial period, they were housed in stalls and fed individually to control the dietary food, stool samples were performed to estimate the digestibility of nutrients. Milking were held twice a day, measuring the production and analysis of milk composition in each experimental period. Blood collections were performed at the end of each period to evaluate the metabolic condition of the cows. The data were analyzed using variance analysis and polynomial regression. The replacement of corn by SRECS did not affect the intake of dry matter (DM) or total carbohydrates (TC). There was a linear decrease in the intake of ether extract (EE), and a linear increase in the intake of neutral (NDF) and acid detergent fiber (ADF), indicating a quadratic regression with the intake of crude protein (CP). The use SRECS presented growing effect digestibility of the ADF, showing a positive linear effect. The total digestible nutrients (TDN) did not differ between the diets and had an average of 66.03%. There was a trend of reduction (10%) in the production, with consequent increase in delight in the concentration of its components. There was no change in the measured metabolites. The use of silage of the residue from the extraction of cassava starch to replace the ground corn on feed, negatively affects the nutrient intake without changing the efficiency of milk production, milk composition, in the same way as blood