Evaluating of Nutrient Composition and Pellet Durability Index on Pellet Supplement with Different Proportion of Protected Soybean Meal (P-SBM) and Selenium (Se)

Pelleting process is one of production costs, and good processing pellets result in higher cost. Even though it is costly, pellet has convenience in feed handling and an increased efficient use of the feed by the animal. By heat processing, it reduces pathogens and increases the digestible starches, which improve feed efficiency. A significant portion of the improvement is related to the physical form of the pellet. The nutrient composition and pellet durability index (PDI) of six group pellet supplement samples with a different proportion of protected soybean meal (P-SBM) and selenium (Se) for dairy cattle feeding was determined. Feed samples were taken and analyzed in the Laboratory of Animal Feed Technology, Faculty of Animal Science Universitas Gadjah Mada. The observed variables were nutrient composition i.e. dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), crude fibre (CF), and total digestible nutrients (TDN), PDI and physical or dimensions (diameter and length) of pellet. The mean values for DM, OM, CP, EE, CF, and TDN in pellets was found to be 94.67, 83.00, 37.01, 1.83, 5.54, and 86.69 %DM, respectively, whereas PDI was 92.18% (tumbling method) and 90.74% (regression equation). Furthermore, an equation was developed for predicting PDI from nutrient composition and pellet dimensions using multiple linear regression: PDI (%) = 25.51 – 2.41× diameter (mm) + 35.05× length (cm) – 2.62 × moisture (%) + 0.99 × nitrogen-free extractives (%) having R = 72.14%. The dairy supplement pellets with a different proportion of protected soybean meal and selenium showed similar nutrient contents, but higher in PDI compare with the control. Moreover, this study, for the first time, deduces that reasonably good prediction of pellet quality in terms of PDI could be possible with the simple measures like chemical composition, pellet diameter and length, which is expected to benefit feed manufacturers and dairy farmers.