The Influence of Microencapsulated Secondary Plant Compounds on Receiving Beef Cattle Performance.

Six-hundred and fifty six newly weaned cross-bred steers (initial BW 254.4±7.9 kg) were utilized to investigate the effects of microencapsulated secondary plant compounds (MSPC) on receiving performance of feedlot steers. We hypothesized that feeding MPSC would improve feedlot performance during the receiving phase of production as compared to monensin and tylosin. The experimental design was a randomized complete block design. Steers were blocked by weight within cattle source and randomly assigned within block by cattle source to one of 4 treatments (n=8 pens/treatment; experimental unit = pen). Treatments consisted of: 1) Control (monensin: 32.8 g/metric ton DM + tylosin: 7.8 g/metric ton DM); 2) monensin only (32.8 g/metric ton DM); 3) MSPC only (148 g/metric ton DM); and 4) MSPC (148 g/metric ton DM) plus monensin (32.8 g/metric ton DM). Steers received a sorghum silage steam-flaked corn based growing diet (14.0 % CP; 1.15 Mcal/kg NEg) over the 56 d receiving period. Steers were individually weighed on d -1, 0, 28, and 56 of the receiving phase. Initial and final body weights were similar across treatments. Day 0-28, 29-56, and d 0-56 ADG, DMI, and feed efficiency were similar across treatments. Morbidity and mortality rates were also similar across treatments. These data indicate, that under the conditions of this experiment, the addition of monensin and tylosin, monensin alone, MSPC alone, or MSPC plus monensin to beef cattle diets resulted in similar beef cattle performance over a 56 d receiving period.