Anrique et al., 2003. Arch. Med. Vet., 35 (1): 13-22

The effect of including ensiled apple pulp (apple pomace) in rations of early lactation dairy cows was evaluated. Treatments were determined by three levels of apple pomace (0, 15, 30% of total intake), plus a common supply of direct-cut grass silage offered ad-libitum and a fixed amount of concentrate; protein content was the same among treatments. The study was organized in three periods of 21 days following a Crossover Latin Square design of four 3 x 3 squares (treatments x periods). Measurments were made on individual basis in the last seven days of each period, and at the end of each, cows were rotated. Standarized (4% fat) and nonstandarized milk production increased with the inclusion of apple pomace (P< 0.05); on average, supplemented cows produced 9% and 5.9% more standarized and non-standarized milk, respectively (P< 0.05). Contents of milk fat and protein were greater with the highest apple pomace supply. Dry matter (DM) intake increased proporcionally with intake of apple pomace (P< 0.05) as a result of a moderately low substitution rate (SR). SR (kg/kg) increased with apple pomace intake; corresponding SR values for medium (2.6 kg DM) and high (4.5 kg DM) apple pomace intake, respectively, were 0.45 and 0.55 kg/kg. Blood levels of ß-hydroxybutyrate (BHB) and urea were normal and fluctuated within reference values independently of apple pomace intake, however, BHB blood levels of supplemented cows were 50% lower compared to controls, suggesting reduced mobilization of body reserves. Results were coherent with a better body weight status displayed by supplemeted cows, which was positively correlated with apple pomace intake, demonstrating that inclusion of apple pomace effectively improved dry matter intake and energy balance