Does pellet size affect the ability of beef heifers to consume a pelleted supplement in a simulated grazing model? (2019)

Kelln, L., Newkirk, R. W., Smillie, J. et al.

Abstract

The objective was to evaluate pellet consumption and refusals as affected by pellet size. Six ruminally cannulated heifers were used in a replicated 3 × 3 Latin square. Heifers were individually housed and fed a diet of grass hay (57.5%), mineral and vitamin supplement (8.0%), and canola meal (11.9%) in a feed bunk, and their respective wheat- and wheat-middling-based treatment pellet (22.7%) on artificial turf. The artificial turf had a mean staple length of 5 cm and a blade density of 45 blades cm-2. The pellets were small (SM; 4 mm diameter), medium (MED; 11 mm diameter), or large (LG; 50 mm diameter) in size. Heifers fed LG had greater pellet intake than SM (2.24 vs. 2.06 kg; P = 0.035), with MED being intermediate (2.12 kg). Heifers fed LG tended to have less pellet waste than SM (P = 0.074). Heifers fed MED pellets had greater concentration of ruminal short-chain fatty acids than SM and LG (91.3 vs. 84.7 and 89.0 mmol L-1; P = 0.009). The results indicate that feeding a LG pellet may increase intake and reduce waste compared with SM, and that pellet size may also affect ruminal fermentation.