Estimating Ribeye Area Using a Longitudinal Ultrasound Image of the 12th and 13th Rib Section

A study was performed to determine the feasability of using a measurement of ribeye depth (RED) from a longitudinal ultrasound image to estimate ribeye area (REA). The correlation between RED obtained with ultrasound and REA from a tracing was high for both implanted (r = .49) and non-implanted (r = .45) steers. The mean bias between predicted REA and actual REA was not different from zero. This analysis shows that RED could be an accurate indicator of REA

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

Potential Value of Ultrasound to Sort Feeder Cattle into More Uniform Groups for Finishing and Marketing

Cattle in three experiments were scanned with ultrasound as feeders to measure ribeye area and thickness of fat cover to determine if cattle could be sorted into outcome groups with respect to carcass yield. Sorting the cattle into low fat cover or large ribeye groups resulted in improved carcass yield grades. There were no effects on carcass quality grades related to sorting of the cattle. Cattle with greater fat cover at the beginning of the feeding period were heavier, seemed to be more mature and had less muscle growth during the finishing period. There were no significant differences in gain among the groups, but cattle with more fat cover had poorer feed efficiency. Ultrasound seems to have potential to sort feeder cattle, but before it can be used in practice, growth curves need to be developed to predict final end points of individual cattle

Long Versus Short Feeding Period for Steer Calves of Three Frame Sizes Fed High Energy Finishing Diets

An experiment was conducted using Angus cross steer calves of three frame sizes (small, medium, and large) to compare performance of two different grow/finish feeding programs. Half of the cattle in each frame size group were fed a high energy ration through the growing period, similar to calves going directly into the feedlot. The other half was fed a low energy ration, similar to a backgrounding diet, for a period prior to the finishing phase. All cattle were fed a high energy ration through the finishing period. The data showed the cattle fed the low energy growing diet experienced some compensatory gains as shown by ultrasound backfat and average daily gains coupled with intakes greater than the increases seen in the high energy treatment. Carcass data and overall performance data showed no ill effects due to the low energy growing ration

The effects of solid rocket motor effluents on selected surfaces and solid particle size, distribution, and composition for simulated shuttle booster separation motors

A series of three tests was conducted using solid rocket propellants to determine the effects a solid rocket plume would have on thermal protective surfaces (TPS). The surfaces tested were those which are baselined for the shuttle vehicle. The propellants used were to simulate the separation solid rocket motors (SSRM) that separate the solid rocket boosters (SRB) from the shuttle launch vehicle. Data cover: (1) the optical effects of the plume environment on spacecraft related surfaces, and (2) the solid particle size, distribution, and composition at TPS sample locations

X-ray analog pixel array detector for single synchrotron bunch time-resolved imaging

Dynamic x-ray studies may reach temporal resolutions limited by only the x-ray pulse duration if the detector is fast enough to segregate synchrotron pulses. An analog integrating pixel array detector with in-pixel storage and temporal resolution of around 150 ns, sufficient to isolate pulses, is presented. Analog integration minimizes count-rate limitations and in-pixel storage captures successive pulses. Fundamental tests of noise and linearity as well as high-speed laser measurements are shown. The detector resolved individual bunch trains at the Cornell High Energy Synchrotron Source (CHESS) at levels of up to 3.7x10^3 x-rays/pixel/train. When applied to turn-by-turn x-ray beam characterization single-shot intensity measurements were made with a repeatability of 0.4% and horizontal oscillations of the positron cloud were detected. This device is appropriate for time-resolved Bragg spot single crystal experiments.Comment: 9 pages, 11 figure

Effect of Ghrelin Injection on Blood and Body Composition in Rats

Ghrelin has been reported to cause hyperglycemia in humans and adiposity in rodents. The objective of trial one was to test the effects of ghrelin on blood and body composition in rats. The objective of trial two was to evaluate the effect of two doses of ghrelin on blood and body composition. Trial One: Adult male Sprague Dawley rats were administered 1 μg/rat ghrelin in 0.15 M NaCl or vehicle (0.15 M NaCl) every morning for 30 days. The terminal blood sample was analyzed for glucose, urea nitrogen, and nonesterified fatty acids concentrations. The carcasses were analyzed for total lipid and nitrogen content. Blood urea nitrogen, nonesterified fatty acids, carcass total lipid, and carcass total nitrogen concentrations were similar for the control and ghrelin groups. However, blood glucose concentration tended to be higher in the ghrelin group than in the control. Ghrelin administered at 2.4 μg/kg did not cause adiposity in rats but did tend to cause hyperglycemia. Trial Two: Adult male Sprague Dawley rats were administered 1 μg/rat ghrelin, 20 μg/rat ghrelin, or vehicle every morning for 30 days. The terminal blood sample was analyzed for glucose and cholesterol concentrations. The carcasses were analyzed for total lipid and nitrogen content. Carcass total nitrogen concentrations were similar for the control and ghrelin groups. Carcass percent lipid was higher in the 1 μg/rat ghrelin group (P = 0.04). Feed intake among all three groups was the same. Blood glucose concentration, however, tended to be higher in the ghrelin groups than in the control. Blood cholesterol concentration was lower in the ghrelin treated animals. In the second trial, ghrelin injection of 1 μg/rat did cause an increase in adiposity whereas 20 μg/rat did not cause an increase in adiposity. Both ghrelin treatments tended to cause hyperglycemia in rats. In summary, ghrelin increased blood glucose concentration without changing body composition

Evaluation of Ultrasound Measurement of Fat Thickness and Ribeye Area, II. Repeatability of Measurements.

Data from two feeding trials were used to evaluate repeatability of ultrasound measurements of fat thickness and ribeye area. In each trial, steers were scanned three or four times by one technician. Two beef improvement federation (BIF)-certified technicians with different levels of experience interpreted images from the last scan. Each technician interpreted the image of an individual steer twice on two different days. Repeatability was evaluated as an intra-class correlation. Additional statistics used to evaluate repeatability were the slope and intercepts from a regression analysis, RMSE, and ESD. Ultrasound measurements of fat thickness and ribeye area were repeatable both within and across technicians. The only exception was the across-technician measurements of ribeye area, where an apparent difference in variances of measurements was observed