Estimates of parameters between direct and maternal genetic effects for weaning weight and direct genetic effects for carcass traits in crossbred cattle

Estimates of heritabilities and genetic correlations were obtained for weaning weight records of 23,681 crossbred steers and heifers and carcass records from 4,094 crossbred steers using animal models. Carcass traits included hot carcass weight; retail product percentage; fat percentage; bone percentage; ribeye area; adjusted fat thickness; marbling score, Warner- Bratzler shear force and kidney, pelvic and heart fat percentage. Weaning weight was modeled with fixed effects of age of dam, sex, breed combination, and birth year, with calendar birth day as a covariate and random direct and maternal genetic and maternal permanent environmental effects. The models for carcass traits included fixed effects of age of dam, line, and birth year, with covariates for weaning and slaughter ages and random direct and maternal effects. Direct and maternal heritabilities for weaning weight were 0.4 ± 0.02 and 0.19 ± 0.02, respectively. The estimate of direct-maternal genetic correlation for weaning weight was negative (−0.18 ± 0.08). Heritabilities for carcass traits of steers were moderate to high (0.34 to 0.60). Estimates of genetic correlations between direct genetic effects for weaning weight and carcass traits were small except with hot carcass weight (0.70), ribeye area (0.29), and adjusted fat thickness (0.26). The largest estimates of genetic correlations between maternal genetic effects for weaning weight and direct genetic effects for carcass traits were found for hot carcass weight (0.61), retail product percentage (−0.33), fat percentage (0.33), ribeye area (0.29), marbling score (0.28) and adjusted fat thickness (0.25), indicating that maternal effects for weaning weight may be correlated with genotype for propensity to fatten in steers

Estimates of parameters between direct and maternal genetic effects for weaning weight and direct genetic effects for carcass traits in crossbred cattle

Estimates of heritabilities and genetic correlations were obtained for weaning weight records of 23,681 crossbred steers and heifers and carcass records from 4,094 crossbred steers using animal models. Carcass traits included hot carcass weight; retail product percentage; fat percentage; bone percentage; ribeye area; adjusted fat thickness; marbling score, Warner- Bratzler shear force and kidney, pelvic and heart fat percentage. Weaning weight was modeled with fixed effects of age of dam, sex, breed combination, and birth year, with calendar birth day as a covariate and random direct and maternal genetic and maternal permanent environmental effects. The models for carcass traits included fixed effects of age of dam, line, and birth year, with covariates for weaning and slaughter ages and random direct and maternal effects. Direct and maternal heritabilities for weaning weight were 0.4 ± 0.02 and 0.19 ± 0.02, respectively. The estimate of direct-maternal genetic correlation for weaning weight was negative (−0.18 ± 0.08). Heritabilities for carcass traits of steers were moderate to high (0.34 to 0.60). Estimates of genetic correlations between direct genetic effects for weaning weight and carcass traits were small except with hot carcass weight (0.70), ribeye area (0.29), and adjusted fat thickness (0.26). The largest estimates of genetic correlations between maternal genetic effects for weaning weight and direct genetic effects for carcass traits were found for hot carcass weight (0.61), retail product percentage (−0.33), fat percentage (0.33), ribeye area (0.29), marbling score (0.28) and adjusted fat thickness (0.25), indicating that maternal effects for weaning weight may be correlated with genotype for propensity to fatten in steers

Precision Studies of Duality in the 't Hooft Model

We address numerical aspects of local quark-hadron duality using the example of the exactly solvable 't Hooft model, two-dimensional QCD with N_c --> infinity. The primary focus of these studies is total semileptonic decay widths relevant for extracting |V_{cb}| and |V_{ub}|. We compare the exact channel-by-channel sum of exclusive modes to the corresponding rates obtained in the standard 1/m_Q expansion arising from the Operator Product Expansion. An impressive agreement sets in unexpectedly early, immediately after the threshold for the first hadronic excitation in the final state. Yet even at higher energy release it is possible to discern the seeds of duality-violating oscillations. We find the ``Small Velocity'' sum rules to be exceptionally well saturated already by the first excited state. We also obtain a convincing degree of duality in the differential distributions and in an analogue of R_{e^+e^-}(s). Finally, we discuss possible lessons for semileptonic decays of actual heavy quarks in QCD.Comment: 45 pages, 16 eps figures include

Needle-free injection enhancement of beef improves tenderness but slightly increases microbial translocation

Blade tenderization has been used for decades to increase tenderness in beef cuts that are highly variable in tenderness or predicted to be “tough.” Injection enhancement also is commonly used in industry to increase tenderness, juiciness, and flavor of some beef muscles. These processes have the potential to translocate microbial organisms on the exterior to interior portions of whole muscles. One research study reported that 3 to 4% of surface bacteria are transferred into the interior of muscles but only penetrate an average of ¼ inch deep into the surface. Even though the frequency of subprimal surfaces being contaminated with pathogens is low, translocation of these contaminants into the interior of subprimals by tenderization or injection procedures poses a public health risk. Microbial contamination on beef surfaces generally is eliminated during typical cooking; however, given the low infectious doses of pathogens such as Escherichia coli O157:H7, internalized contamination may survive if adequate temperatures are not reached at the center of cuts (i.e., rare and medium rare endpoints) and lead to illness. Industry groups have developed a guide, Best Practices: Pathogen Control During Tenderizing/Enhancing of Whole Muscle Cuts to minimize any hazard that may be present with such technologies. Although needle injection enhancement currently is common in beef processing, there may be alternative, safer, or more effective means to apply these technologies. One potential method involves utilizing an air-pressured needle-free injection system similar to an instrument currently being investigated for use in vaccinating cattle. In theory, eliminating the need for physical penetration of the muscle with a needle-free instrument using air-pressure fluid streams would reduce the translocation of surface microbial contamination to the interior and would additionally minimize carryover contamination from subprimal to subprimal during continuous injection operations. Therefore, we investigated use of needle-free injection enhancement as an alternative strategy to needle injection enhancement. Our objectives were to determine the safety and efficacy of using needle-free injection for enhancing beef muscles and the application of needle-free injection enhancement for improving beef quality

Genetic relationships between sex-specific traits in beef cattle: Mature weight, weight adjusted for body condition score, height and body condition score of cows, and carcass traits of their steer relatives

Data from the first four cycles of the Germplasm Evaluation Program at the U.S. Meat Animal Research Center (USMARC) were used to investigate genetic relationships between mature weight (MW, n = 37,710), mature weight adjusted for body condition score (AMW, n = 37,676), mature height (HT, n = 37,123), and BCS (n = 37,676) from 4- to 8-yr old cows (n = 1,800) and carcass traits (n = 4,027) measured on their crossbred paternal half-sib steers. Covariance components among traits were estimated using REML. Carcass traits were adjusted for age at slaughter. Estimates of heritability for hot carcass weight (HCWT); percentage of retail product; percentage of fat; percentage of bone; longissimus muscle area; fat thickness adjusted visually; estimated kidney, pelvic, and heart fat percentage; marbling score; Warner-Bratzler shear force; and taste panel tenderness measured on steers were moderate to high (0.26 to 0.65), suggesting that selection for carcass and meat traits could be effective. Estimates of heritability for taste panel flavor and taste panel juiciness were low and negligible (0.05 and 0.01, respectively). Estimates of heritability from cow data over all ages and seasons were high for MW, AMW, and HT (0.52, 0.57, 0.71; respectively) and relatively low for BCS (0.16). Pair-wise analyses for each female mature trait with each carcass trait were done with bivariate animal models. Estimates of genetic correlations between cow mature size and carcass composition or meat quality traits, with the exception of HCWT, were relatively low. Selection for cow mature size (weight and/or height) could be effective and would not be expected to result in much, if any, correlated changes in carcass and meat composition traits. However, genetic correlations of cow traits, with the possible exception of BCS, with HCWT may be too large to ignore. Selection for steers with greater HCWT would lead to larger cows

Genetic analysis of carcass traits of steers adjusted to age, weight, or fat thickness slaughter endpoints

Carcass measurements from 1,664 steers from the Germ Plasm Utilization project at U.S. Meat Animal Research Center were used to estimate heritabilities (h2) of, and genetic correlations (rg) among, 14 carcass traits adjusted to different endpoints (age, carcass weight, and fat thickness): HCW (kg), dressing percent (DP), adjusted fat thickness (AFT, cm), LM area (LMA, cm2), KPH (%), marbling score (MS), yield grade (YG), predicted percentage of retail product (PRP), retail product weight (RPW, kg), fat weight (FW, kg), bone weight (BNW, kg), actual percentage retail product (RPP), fat percent (FP), and bone percent. Fixed effects in the model included breed group, feed energy level, dam age, birth year, significant (P \u3c 0.05) interactions, covariate for days on feed, and the appropriate covariate for endpoint nested (except age) within breed group. Random effects in the model were additive genetic effect of animal and total maternal effect of dam. Parameters were estimated by REML. For some traits, estimates of h2 and phenotypic variance changed with different endpoints. Estimates of h2 for HCW,DP, RPW, and BNW at constant age, weight, or fat thickness were 0.27, —, and 0.41; 0.19, 0.26, and 0.18; 0.42, 0.32, and 0.50; and 0.43, 0.32, and 0.48, respectively. Magnitude and/or sign of rg also changed across endpoints for 54 of the 91 trait pairs. Estimates for HCW-LMA, AFTRPW, LMA-YG, LMA-PRP, LMA-FW, LMA-RPP, and LMA-FP at constant age, weight, or fat thickness were 0.32, —, and 0.51; −0.26, −0.77, and —; −0.71, −0.89, and −0.66; 0.68, 0.85, and 0.63; −0.16, −0.51, and 0.22; 0.47, 0.57, and 0.27; and −0.44, −0.43, and −0.18, respectively. Fat thickness was highly correlated with YG (0.86 and 0.85 for common age and weight) and PRP (−0.85 and −0.82 for common age and weight), indicating that selection for decreased fat thickness would improve YG and PRP. Carcass quality, however, would be affected negatively because of moderate rg (0.34 and 0.35 for common age and weight) between MS and AFT. Estimates of h2 and phenotypic variance indicate that enough genetic variation exists to change measures of carcass merit by direct selection. For some carcass traits, however, magnitude of change would depend on effect of endpoint on h2 and phenotypic variance. Correlated responses to selection would differ depending on endpoint

Dipole coefficients in B -> X_s gamma in supersymmetry with large \tan\beta and explicit CP violation

We perform a detailed study of the electric and chromoelectric dipole coefficients in B -> X_s \gamma decay in a supersymmetric scheme with explicit CP violation. In our analysis, we adopt the minimal flavor violation scheme by taking into account the \tan\beta-enhanced large contributions beyond the leading order. We show that the coefficients can deviate from the SM prediction significantly in both real and imaginary directions. Experimental bounds still allow for large deviations from the SM predictions for both dipole coefficients such that the CP asymmetry is as large as \pm 8%. There are further implications of these coefficients for the charmless hadronic and semileptonic B decays. As a direct application of our analysis, we have discussed \Lambda_b -> \Lambda \gamma decay.Comment: 14 pp, 13 ps figs, a direct application of the computations is given, some figures and references are adde

Bremsstrahlung corrections to the decay b→sγb \to s \gamma

We calculate the O($\alpha_s$) gluon Bremsstrahlung corrections to the inclusive decay $b \rightarrow s \gamma$, involving the full operator basis $\hat O_1$ -- $\hat O_8$. Confirming and extending earlier calculations of Ali and Greub, we give formulas for the total decay width as well as the perturbative photon spectrum, regarding the former as a necessary part of the forthcoming complete NLO analysis. We explore in detail the renormalization scale dependence of our results and find it considerably increased.Comment: 23 pages, LaTeX, uses epsf.sty and rotate.sty. 4 figures (uuencoded postscript) appended as seperate file. A complete postscript version may be obtained from URL ftp://feynman.t30.physik.tu-muenchen.de/pub/preprints/tum-93-95.ps.gz Final version as to appear in Physical Review D. Some minor errors corrected, without changes in the numerical results. One reference adde

Two-loop matching of the dipole operators for b→sγb \to s \gamma and b→sgluonb \to s gluon

The order $\alpha_s$ corrections to the Wilson coefficients of the dipole operators ($O_7,O_8$) at the matching scale $\mu =m_W$ are a crucial ingredient for a complete next- to-leading logarithmic calculation of the branching ratio for $b \to s \gamma$. Given the phenomenological relevance and the fact that this two-loop calculation has been done so far only by one group [1], we present a detailed re-calculation using a different method. Our results are in complete agreement with those in ref. [1].Comment: 24 pages, latex, 6 figures include

Extracting V_{ub} Without Recourse to Structure Functions

We present a closed form expression for |V_{ub}|^2/ |V_{tb} V_{ts}^*|^2 in terms of the endpoint photon and lepton spectra from the inclusive decays B -> X_s\gamma and B -> X_u\ell\nu, respectively, which includes the resummation of the endpoint logs at next to leading order and is completely independent of the B meson structure function. The use of this expression for extracting V_{ub} would eliminate the large systematic errors usually incurred due to the modeling of the heavy quarks' Fermi motion.Comment: 20 pages, no figures, minor typos correcte