The use of physical measurements in live cattle to predict carcass composition

1991 ◽  
Vol 31 (4) ◽  
pp. 479 ◽  
Author(s):  
ER Johnson ◽  
CB Davis
Keyword(s):  
Standard Error ◽  
Gluteus Medius ◽  
Carcass Composition ◽  
Standard Errors ◽  
Physical Measurements ◽  
Fat Thickness

Of 13 physical measurements made on live cattle, anal fold fat thickness measured with a hand caliper and fasted liveweight were the most accurate predictors of carcass composition, particularly when used together. Anal fold fat thickness plus fasted liveweight predicted the percentages (mean � s.e. of estimate) of side muscle (59.62 � 1.80), side bone (14.23 � 0.81) and side fat (23.58 � 2.18). Scanoprobe measurements made on live animals were correlated (P<0.01) with the actual carcass measurements as follows: fat thickness at the 10th rib, 0.50; fat thickness at the 12th rib, 0.69; muscle depth at the 10th rib, 0.56; muscle depth at the 12th rib, 0.66. Anal fold fat thickness, with a standard error of estimate of 2.22%, was a better predictor of percentage side muscle than the live Scanoprobe measurements, depth of M. longissimus at the 12th rib (3.44%) and depth of M. gluteus medius (3.61%). When used to measure the fat depth over M. longissimus at the 12th rib in live cattle, the standard errors of estimate of the Scanoprobe in predicting percentage side muscle and percentage side fat were not significantly different from those of anal fold fat thickness determined with the caliper. For the prediction of percentage side muscle the errors for Scanoprobe and caliper were 3.44 and 2.22, respectively; for the prediction of percentage side fat they were 3.79 and 3.12, respectively. Tuber coxae width, the most accurate of the linear skeletal measurements in predicting side bone percentage, was not as accurate as anal fold fat thickness (s.e. of estimate, 1.02 v. 0.89%).

The use of carcass cuts to predict beef carcass composition: a research technique

1981 ◽  
Vol 32 (6) ◽  
pp. 987 ◽  
Author(s):  
ER Johnson ◽  
DD Charles
Keyword(s):  
Multiple Regression ◽  
Prediction Accuracy ◽  
Carcass Composition ◽  
Standard Errors ◽  
Regression Analyses ◽  
Slight Improvement ◽  
B Values ◽  
Bone Content ◽  
Fat Thickness ◽  
Carcass Cuts

Eleven Angus, 12 Friesian and 12 Hereford steers were used to investigate the degree of accuracy and usefulness of primal cut tissues in predicting side composition. The criteria used for evaluating the cuts were: (a) standard error of estimate of the equation, (b) homogeneity of 'b' values among breeds, (c) appreciable bone content in cut to allow the prediction of side bone, and (d) the absence of major difficulties in the replication and dissection of cuts. Simple and multiple regression analyses showed that the most accurate predictors of carcass composition, in descending order, with standard errors of estimate of muscle, fat and bone percentages respectively, were: hindquarter plus rib cut (0.37 %, 0.47 %, 0.30 %); hindquarter (0.73 %, 0.87%, 0.49%); loin plus rib cut (0.84%, 0.88%, 0.48%); rib cut (1.13%, 1.26%, 0.59%); loin (1.24%, 1.21 %, 0.72%). The most useful of four easily obtained carcass variables in improving the prediction accuracy of carcass components from multiple regression proved to be primal cut weight and fat thickness at the 12th rib, particularly the former. Both significantly reduced the standard errors of estimate of muscle, fat or bone in equations based on loin, rib cut and loin plus rib cut, but not in equations based on hindquarter plus rib cut and hindquarter. Kidney plus pelvic fat weight was of limited value, resulting only in a slight improvement in the prediction of side bone percentage using the equations based on bone percentage of the hindquarter. Carcass weight was of equal value to primal cut weight in improving the prediction accuracy of multiple regression. Five sets of part-carcass prediction equations are given, providing a choice of prediction accuracy, labour expenditure and cost for research workers whose requirements and resources may vary.

Multi-Center Calibration of the Second Reference Material for Thromboplastin, Rabbit, Plain, Coded CRM 149R

1991 ◽  
Vol 65 (03) ◽  
pp. 263-267 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina
Keyword(s):  
Reference Material ◽  
Standard Error ◽  
Standard Errors ◽  
Sensitivity Index ◽  
Long Term Stability ◽  
Significant Bias ◽  
The Mean ◽  
The Relationship ◽  
International Sensitivity Index

SummaryIn a collaborative trial of eleven laboratories which was performed mainly within the framework of the European Community Bureau of Reference (BCR), a second reference material for thromboplastin, rabbit, plain, was calibrated against its predecessor RBT/79. This second reference material (coded CRM 149R) has a mean International Sensitivity Index (ISI) of 1.343 with a standard error of the mean of 0.035. The standard error of the ISI was determined by combination of the standard errors of the ISI of RBT/79 and the slope of the calibration line in this trial.The BCR reference material for thromboplastin, human, plain (coded BCT/099) was also included in this trial for assessment of the long-term stability of the relationship with RBT/79. The results indicated that this relationship has not changed over a period of 8 years. The interlaboratory variation of the slope of the relationship between CRM 149R and RBT/79 was significantly lower than the variation of the slope of the relationship between BCT/099 and RBT/79. In addition to the manual technique, a semi-automatic coagulometer according to Schnitger & Gross was used to determine prothrombin times with CRM 149R. The mean ISI of CRM 149R was not affected by replacement of the manual technique by this particular coagulometer.Two lyophilized plasmas were included in this trial. The mean slope of relationship between RBT/79 and CRM 149R based on the two lyophilized plasmas was the same as the corresponding slope based on fresh plasmas. Tlowever, the mean slope of relationship between RBT/79 and BCT/099 based on the two lyophilized plasmas was 4.9% higher than the mean slope based on fresh plasmas. Thus, the use of these lyophilized plasmas induced a small but significant bias in the slope of relationship between these thromboplastins of different species.

Estimation of the carcass composition of different cattle breeds and crosses from fatness measurements and visual assessments

1986 ◽  
Vol 106 (2) ◽  
pp. 223-237 ◽  
Author(s):  
A. J. Kempster ◽  
J. P. Chadwick ◽  
D. D. Charles
Keyword(s):  
Subcutaneous Fat ◽  
Visual Assessment ◽  
Carcass Composition ◽  
Beef Breed ◽  
Percentage Unit ◽  
Wide Range ◽  
Fat Thickness ◽  
Substantial Bias ◽  
Visual Assessments ◽  
Thickness Measurements

SUMMARYCarcass data for 1053 steers from the Meat and Livestock Commission's beef breed evaluation programme were used to examine the relative precision of alternative fatness assessments for predicting carcass lean percentage. The data were from four trials and comprised both dairy-bred and suckler-bred cattle by a wide range of sire breeds.A visual assessment of carcass subcutaneous fat content to the nearest percentage unit (SFe) was the single most precise predictor both overall (residual S.d. = 2·28) and within breed (residual S.d. = 2·05). Precision was improved by the addition in multiple regression of the percentage perinephric and retroperitoneal fat (KKCF) in carcass, a visual score of the degree of marbling in the m. longissimus and selected fat thickness measurements taken by calipers on cut surfaces (residual S.d. = 2·11 (overall) and 1·90 (within breed)).When the best overall equation was applied to the breed means, there was substantial bias (predicted – actual carcass lean percentage). Biases ranged from +2·5 (purebred Canadian Holstein and Luing) to – 1·3 (Limousin crosses).Breeds differed significantly in carcass lean content when compared at equal levels of fatness measurements. The differences depended both on the precision with which the measurements predicted carcass lean content and the observed differences in carcass composition that existed before adjustments to equal fatness were made.The robustness of prediction equations was examined by applying them to independent sets of data (a total of 334 carcasses) from four other trials involving steers, heifers, cows and young bulls. Equations were stable for cattle of the same breed, sex and similar levels of fatness but important bias was found between more extreme types of cattle.

On the Smoothing of Observed Data

1937 ◽  
Vol 33 (4) ◽  
pp. 444-450 ◽  
Author(s):  
Harold Jeffreys
Keyword(s):  
Standard Error ◽  
Random Error ◽  
Simple Function ◽  
Standard Errors ◽  
Random Errors ◽  
Previous Theory ◽  
Know How ◽  
True Value ◽  
Actual Error ◽  
Range Of Variation

1. It often happens that we have a series of observed data for different values of the argument and with known standard errors, and wish to remove the random errors as far as possible before interpolation. In many cases previous considerations suggest a form for the true value of the function; then the best method is to determine the adjustable parameters in this function by least squares. If the number required is not initially known, as for a polynomial where we do not know how many terms to retain, the number can be determined by finding out at what stage the introduction of a new parameter is not supported by the observations*. In many other cases, again, existing theory does not suggest a form for the solution, but the observations themselves suggest one when the departures from some simple function are found to be much less than the whole range of variation and to be consistent with the standard errors. The same method can then be used. There are, however, further cases where no simple function is suggested either by previous theory or by the data themselves. Even in these the presence of errors in the data is expected. If ε is the actual error of any observed value and σ the standard error, the expectation of Σε2/σ2 is equal to the number of observed values. Part, at least, of any irregularity in the data, such as is revealed by the divided differences, can therefore be attributed to random error, and we are entitled to try to reduce it.

An assessment of carcass probes for use in Great Britain for the EC pig Carcass Grading Scheme

1989 ◽  
Vol 48 (2) ◽  
pp. 427-434 ◽  
Author(s):  
G. L. Cook ◽  
J. P. Chadwick ◽  
A. J. Kempster
Keyword(s):  
Great Britain ◽  
Subcutaneous Fat ◽  
Optical Probe ◽  
Carcass Composition ◽  
Coefficient Of Determination ◽  
The Third ◽  
Slaughter Pigs ◽  
Fat Thickness ◽  
Statistical Criteria ◽  
Do So

ABSTRACTTo gain approval for use in the revised European Community (EC) Pig Grading Scheme to be introduced in 1989, methods of estimating carcass lean proportion must be shown to do so with a coefficient of determination greater than 0·64 and a residual s.d. of less than 25 g/kg. A trial was carried out to assess a number of methods for use in the EC Scheme as applied in Great Britain. Subcutaneous fat and m. longissimus depths at the head of the last rib and at the third/fourth from last rib were measured using the optical probe (OP), the Fat-O-Meater (FOM), the Hennessy Grading Probe II (HGP) and the Destron PG-100 Probe (DST) on a broad sample of 162 commercial carcasses representative of the ranges in fatness and weight found nationally. The left side of each carcass was separated into component tissues. Although the instruments all achieved similar levels of accuracy in predicting carcass lean proportion, some differences were found. The DST just failed to reach the required statistical criteria for approval in the EC Scheme. The results for the other three instruments were submitted to Brussels as evidence of suitability and they have been approved.Using the regression relationships found between carcass composition and fat thickness together with results from earlier studies, it was estimated that the carcass separable fat proportion of British slaughter pigs has fallen at the annual rate of 7 g/kg since 1975.

scholarly journals Integration of macromolecular diffraction data

1999 ◽  
Vol 55 (10) ◽  
pp. 1696-1702 ◽  
Author(s):  
A. G. W. Leslie
Keyword(s):  
Diffraction Data ◽  
Standard Error ◽  
Standard Errors ◽  
X Ray ◽  
Poisson Statistics ◽  
Profile Fitting ◽  
X Ray Background

Diffraction intensities can be evaluated by two distinct procedures: summation integration and profile fitting. Equations are derived for evaluating the intensities and their standard errors for both cases, based on Poisson statistics. These equations highlight the importance of the contribution of the X-ray background to the standard error and give an estimate of the improvement which can be achieved by profile fitting. Profile fitting offers additional advantages in allowing estimation of saturated reflections and in dealing with incompletely resolved diffraction spots.

Improved method for estimating Ca uptake in vascular smooth muscle using compartmental analysis

1990 ◽  
Vol 259 (1) ◽  
pp. R172-R183 ◽  
Author(s):  
H. A. Massaldi ◽  
J. Copello ◽  
A. Muller ◽  
M. F. Villamil
Keyword(s):  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Standard Error ◽  
Compartmental Analysis ◽  
Compartment Model ◽  
Parameter Estimate ◽  
Estimation Methods ◽  
Standard Errors ◽  
Influx Rate ◽  
Ca Uptake

A comparative study on the modeling aspects of Ca uptake in vascular smooth muscle is presented with particular emphasis on determination of the influx rate and its standard error for one- and two-compartment models. Experimental data from our laboratory of 45Ca uptake by dog carotid arteries were optimally fitted to a one-compartment model and were used to compare different estimation methods and experiment designs. Reparameterization of the model equation yielded an expression that allows direct estimation of the influx rate and its standard error. Experiment design with replicated sampling at three to four times were found to provide the highest estimation precision and successful comparisons of influx rates under treatment and control conditions. Two-compartment model data reported in the literature for Ca uptake by cells were reprocessed, yielding standard errors for the rate constant of the fast component an order of magnitude larger than the mean estimate. For this case, a three-parameter variant of the one-compartment model was developed that described the data with acceptable standard errors. Overall we found that the choice of the model that fitted Ca uptake data best required consideration of parameter estimate precision comparisons in addition to F tests of significance between alternate models.

THE EFFECT OF RIBBING SITE ON FAT THICKNESS MEASUREMENTS AND THE PREDICTION OF BEEF CARCASS COMPOSITION

1986 ◽  
Vol 66 (2) ◽  
pp. 541-545
Author(s):  
S. D. M. JONES ◽  
A. K. W. TONG ◽  
A. H. MARTIN ◽  
W. M. ROBERTSON
Keyword(s):  
Key Words ◽  
Fat Content ◽  
Carcass Composition ◽  
Prediction Equations ◽  
Beef Carcasses ◽  
Fat Thickness ◽  
Standard Deviations ◽  
Thickness Measurements ◽  
Beef Carcass

Over a 2-yr period, 409 beef carcasses were used to assess the differences of ribbing site (11/12th vs. 12/13th) on fat thickness measurements and the use of these measurements to predict carcass composition. Minimum fat thickness taken at the location specified for use under Canadian beef carcass grading procedures was 1.6 mm less, averaged over all carcasses at the 13th rib, compared with the same measurement taken at the 12th rib. Prediction equations for estimating carcass lean or fat content based on coefficients of determination and residual standard deviations had similar precision using fat thickness measurements from either ribbing site. These results are discussed in reference to National carcass grading procedures. Key words: Carcass grading, fat thickness, carcass composition

scholarly journals Hipparcos, Three Years After Launch

1993 ◽  
Vol 156 ◽  
pp. 1-10
Author(s):  
J. Kovalevsky ◽  
M. Froeschlé
Keyword(s):  
Standard Error ◽  
Present Status ◽  
Double Star ◽  
New Method ◽  
Standard Errors ◽  
First Year ◽  
Mass Determination ◽  
Mission Duration ◽  
The Mean

In a first part, the present status of the HIPPARCOS mission is described. Despite the degradations and failures of gyroscopes, it is still hoped that a 4 1/2 mission duration will be reached. The first-year of data has been reduced by both FAST and NDAC consortia. For the best 46200 observed stars, the distribution of standard errors in positions has a maximum of 1.5 mas in latitude and 1.8 mas in longitude and the mean standard error for parallaxes is of the order of 3 mas. The comparison of results obtained by both consortia shows that the differences are small and quite consistent with the announced internal precisions. Magnitude measurements are precise to 0.02 magnitude for a 4 second observation. The precision to be expected for double star observations is also given. The main new result is that the magnitudes of the components are obtained with a few hundredths of a magnitude precision. This allows to devise a new method of mass determination based upon the parallax and a recalibrated mass-luminosity diagram. The parallax dependence of the results is much more favourable than in the case of the classical determination of masses using orbital motions.

Comparative analysis of five methods for recovering rhizobacteria from cotton roots

1991 ◽  
Vol 37 (12) ◽  
pp. 953-957 ◽  
Author(s):  
Joseph W. Kloepper ◽  
Walter F. Mahaffee ◽  
John A. McInroy ◽  
Paul A. Backman
Keyword(s):  
Bacillus Subtilis ◽  
Pseudomonas Fluorescens ◽  
Standard Error ◽  
Root Colonization ◽  
Glass Beads ◽  
Standard Errors ◽  
Subtilis Strain ◽  
Bacterial Populations ◽  
Recovery Method ◽  
Cotton Seeds

A variety of methods have been used for recovering introduced bacteria from plant roots. The objective of this study was to compare systematically five methods: agitation in buffer, agitation with glass beads in buffer, mixing in a StomacherR lab-blender, sonication, and trituration with mortar and pestle. Cotton seeds were treated with two previously reported rhizobacterial strains, Pseudomonas fluorescens strain Pf-5 and Bacillus subtilis strain GB03. The efficiency of recovery by each method was determined 3 weeks later by comparing average bacterial populations from whole root systems, single 2.0-cm root segments, and two root regions (the uppermost 5 cm of taproot and the lowermost 5 cm). Treatment with the StomacherR blender yielded significantly higher (P = 0.05) mean populations of GB03 compared with all other methods and significantly higher mean populations of Pf-5 compared with agitation with glass beads. From the lowermost 5 cm of taproot, populations of Pf-5 recovered by the StomacherR treatment were significantly higher than all other methods. The inclusion of glass beads for agitation treatments resulted in neither consistently higher absolute numbers of recovered bacteria nor reductions in variability. The mean standard error of each recovery method varied among root sources, and no single method consistently had the highest or lowest mean standard error. Mean standard errors for strain GB03 were generally lower than those for Pf-5 with each root source and each method of recovery. When viewed in composite, the data suggest that the StomacherR treatment was the best for recovering the greatest absolute numbers of rhizobacteria; however, this treatment had high mean standard errors. Investigations of root colonization by introduced rhizobacteria should include several recovery methods to optimize recovered numbers or to decrease variability, depending on the experimental objectives. Key words: root colonization, rhizobacteria, Pseudomonas fluorescens, Bacillus subtilis, cotton.

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