Date of Award
Master of Science
M. P. Hoffman
The objectives of this experiment were to evaluate the use of condensed corn distillers solubles (CCDS) mixed with chopped corn stalks on an intensive cool-season pasture and drylot growing-finishing program. A three-year study was conducted, using 112 Angus and Angus crossbred steer calves each year. Calves were weighed and assigned to four treatment groups by weight and color pattern, with four replications, and seven cattle per replication in each year. Treatments one (FEEDLOT) and two (F+CCDS) were fed in the feedlot from May until harvested. FEEDLOT included chopped alfalfa hay and corn, and F+CCDS included chopped corn stalks and CCDS. Treatment three (PASTURE) and four (P+CCDS) utilized rotational smooth bromegrass pasture grazing (May-September) with P+CCDS also receiving chopped corn stalks and CCDS. Following pasture, chopped alfalfa hay and corn for PASTURE treatment, and chopped corn stalks with CCDS for P+CCDS treatment were provided during the feedlot finishing period. Steers were weighed every 28 days, and daily feed intake was recorded to obtain feed consumption and feed conversion among the treatments during drylot feeding. The smooth bromegrass pasture consisted of 24 paddocks, each 0.69 ha in size. Cattle were fed to a average of 590 kg and harvested to obtain carcass measurements. Comparing FEEDLOT vs F+CCDS and PASTURE vs. P+CCDS, FEEDLOT and PASTURE cattle had greater daily DMI and ADG (P<0.05) than did cattle fed F+CCDS and P+CCDS, respectively. Feed conversion during the drylot feeding period favored FEEDLOT over F+CCDS and PASTURE over P+CCDS cattle (P<0.05), and overall FEEDLOT and F+CCDS over PASTURE and P+CCDS cattle (P<0.05). When cattle on PASTURE and P+CCDS treatments were removed from pasture, P+CCDS cattle had gained well over .23 kg/d better than PASTURE cattle. Though this advantage did not carry over into drylot feeding period, this might be a function of daily energy intake while on pasture. Average carcass weights and liver abscesses were not significantly different across the treatments, but differences were found among treatments (P<0.05) for ribeye area (REA), backfat thickness (BF) and kidney, pelvic and heart fat (KPH). The FEEDLOT cattle had larger REA compared with P+CCDS cattle. The BF was greatest in FEEDLOT cattle compared with cattle of the other treatments (P<0.05). A difference existed in quality grade for FEEDLOT vs P+CCDS cattle (P<0.05). However, overall treatment responses for quality grades were similar and within low Choice and Choice grades. The yield grade was not different among the treatments (P>0.05). Using actual costs, cattle fed F+CCDS were most profitable compared with cattle of other treatments (P<0.05). The FEEDLOT treatment was least profitable, and PASTURE and P+CCDS treatments were intermediate and not different from each other (P>0.05). From these results, we can conclude that substituting corn stalks with CCDS in a drylot finishing system is most profitable, furthermore, incorporating pasture into a feedlot finishing system with or without CCDS may be more profitable than plane drylot finishing.
Purevjav, Tsengeg, "Incorporating condensed corn distillers solubles into an integrated pasture and drylot finishing system for feedlot steers" (2008). Graduate Theses and Dissertations. 10887.