Use of Ultrasound Backfat Estimates to Form Marketing Groups Prior to Finishing for Feedlot Steers

An experiment was conducted using 95 Continental crossbred steers. The cattle were sorted by ultrasound 160 days before slaughter into a low backfat group (Low BF) and a higher backfat group (High BF). Half of the Low BF and half of the High BF were implanted whereas the other halves were not. Data from the experiment were used in two hypothetical markets. One market was a high yield beef program (HY) that did not allow the use of implants. The second market was a commodity beef program (CM) that allowed the use of implants. The cattle were priced as an unsorted group (ALL) and two sorted groups (Low BF and High BF) within the HY (non-implanted) and CM (implanted) markets. The CM program had a base price of $1.05/lb hot carcass weight (HCW) with a $0.15/lb HCW discount for quality grade (QG) Select and a $0.20/lb HCW discount for yield grade (YG) 4. The HY program used a base price of $1.07/lb HCW with premiums ($/lb HCW) paid for YG £ .9 (.15), 1.0 - 1.4 (.10), and 1.5 - 1.9 (.03). The carcasses were discounted ($/lb HCW) for YG 2.5 - 2.9 (.03), 3.0 - 3.9 (.15), and ³ 4.0 (.35). This data set provides good evidence that the end point at which to sell a group of cattle depends on the particular market. Sorting had an economic advantage over ALL in the HY Low BF and the CM High BF groups. The HY High BF cattle should have been sold sooner due to the discounts recieved for increased YG. The increased YG was directly affected by an increase in BF. Furthermore, the CM Low BF group should have been fed longer to increase the number of carcasses grading Choice.

Integration of Pasturing Systems for Cattle Finishing Programs: A Progress Report

A three-year study was conducted to integrate pasturing systems with drylot feeding systems. Each year 84 fall-born and 28 spring-born calves of similar genotypes were used. Fall-born calves were started on test in May, and spring-born calves were started in October. Seven treatments were imposed: 1) fall-born calves directly into the feedlot (28 steers); 2 and 3) fall-born calves put on pasture with or without an ionophore and moved to the feedlot at the end of July (14 steers in each treatment); 4 and 5) fall-born calves put on pasture with or without an ionophore and moved to the feedlot at the end of October (14 steers in each treatment); and 6 and 7) spring-born calves put on pasture with or without an ionophore and moved to the feedlot at the end of October (14 steers in each treatment). Cattle on pasture receiving an ionophore gained faster (P=.009), but lost this advantage in drylot (P>.10). Overall, cattle started directly in the feedlot had higher gains (P<.001). Cattle receiving an ionophore on pasture had lower KPH than those that did not receive an ionophore (P<.01). Treatment influenced yield grade (P<0.001), although all treatments were YG 2. The percentage of cattle grading Prime and Choice was 75 % or higher for all treatment groups. The results show that using an ionophore improved pasture gains and that pasture treatments did not adversely influence yield and quality grades.

Effect of Early Weaning of Beef Calves on Performance and Carcass Quality

A study was conducted to evaluate early weaning of beef calves at 60-70 days of age on feedlot performance and carcass characteristics. One hundred twenty steer calves sired by either Simmental or Angus sires were weaned at an average age of 67 (early weaned, EW) or 147 (late weaned, LW) days. Calves were allotted to 16 feedlot pens by weaning treatment and sire breed at approximately 750-800 lb. EW calves were heavier (P < .05) in initial feedlot weight. There were no differences due to weaning age on daily gain, dry matter intake, feed efficiency or slaughter weights. Simmental steers required more days on feed than Angus steers (P < .05). Early-weaned calves had a higher percent intramuscular fat (5.7 vs. 5.1%), higher average marbling scores (Small78 vs. Small20, P < .05), a higher percentage of cattle grading average USDA Choice and higher (38% vs. 14%, P < .05) and a higher percentage of USDA Prime (10% vs. 0%, P < .05). These data confirm observations in previous studies that early weaning and placing calves on a higher grain diet improves marbling at slaughter. In this study, the effect was shown in calves weaned at an average of 67 days.