Use of birth weight as a predictor of genetic merit of subsequent growth traits in Duroc and Landrace pigs.

Analysis of correlation between the early testable phenotypes of piglets and the final performance of pigs can serve the early selection for breeding. The objectives of this study were to estimate the genetic parameters for birth weight (BtW), age (AGE) and backfat thickness (BF) up to 115 kg BW and to analyse the relationships among these three traits, and to estimate the accuracy of using BtW to predict estimated breeding values (EBVs) of AGE and BF in Landrace and Duroc pigs. Data on 26 614 Landrace and 19 984 Duroc pigs, born between 2001 and 2018, were collected from the core breeding group of a farm. All pigs were recorded for phenotypes including BtW, AGE and BF. The factors affecting these three traits were analysed using R v4.2.0 Software. The population genetic parameters and breeding values of three traits were estimated by using a multitrait animal model based on AI plate of DMU software. Heritabilities for BtW, AGE and BF were moderate to high for Landrace (0.437, 0.282and 0.137, respectively) and Duroc breeds (0.369, 0.279 and 0.148). BtW was genetically correlated with AGE and BF in Landrace (-0.213, 0.037) and Duroc (-0.214, 0.025). AGE was negatively genetically correlated with BF in both Landrace (-0.036) and Duroc (-0.057) pigs. The heritability of BtW, AGE and BF of Landrace pigs and Duroc pigs were 0.148, 0.182 and 0.075 and 0.168, 0.159 and 0.120, respectively, by taking into account of the litter effect. BtW was genetically correlated with AGE and BF in Landrace (-0.094, 0.002) and Duroc (-0.199, -0.052). AGE was negatively genetically correlated with BF in both Landrace (-0.034) and Duroc (-0.153) pigs. The variances between total individual BtW and AGE and BF were then used to predict the EBV of AGE and BF for individuals with AGE or BF phenotypes missing under 10-fold cross-validation. Prediction accuracy was calculated as the Kendall tau-b correlation coefficient between EBVs and EBVs via 10-fold cross-validation. Prediction accuracy for AGE and BF was 0.655 and 0.611 in Landrace, 0.665 and 0.617 in Duroc. After incorporation of the litter effect, the prediction accuracy for AGE and BF increased to 0.690 and 0.665 in Landrace and to 0.705 and 0.649 in Duroc. So, the EBV of AGE and BF phenotypes missing individuals could be predicted by using the available phenotypic data and the easily measured BtW, and litter effect could boost the accuracy of prediction.

Effects of rare-earth size on the electronic structure of La1−xLuxVO3.

The electronic structure of La(1-x)Lu(x)VO(3)(x = 0, 0.2, 0.6 and 1) single crystals has been investigated using soft x-ray absorption spectroscopy, soft x-ray emission spectroscopy, and resonant soft x-ray inelastic scattering to study the effects of rare-earth size. The x-ray absorption and emission spectra at the O K-edge present a progressive evolution with R-site cation, in agreement with local spin density approximation calculations. This evolution with R, together with the temperature dependence of the O K-edge spectra, is attributed to changes in the crystal structure of La(1-x)Lu(x)VO(3). The crystal-field dd. excitations probed by resonant inelastic x-ray scattering at the V L(3)-edge exhibit an increase in energy and enhanced intensity with the decrease of R-site ionic radius, which is mainly attributed to the increased tilting magnitude of the VO(6) octahedra. Upon cooling to ~95 K, the dd* excitations are prominently enhanced in relative Intensity, in agreement with the formation of the Jahn.Teller distortion int he orbital ordering phase. Additionally, the dd* transitions of the mixed compounds are noticeably suppressed with respect to those of the pure compounds, possibly owing to the formation of C-type orbital ordering induced by large R-site size variances.

Resonant soft-X-ray emission as a bulk probe of correlated electron behavior in metallic SrxCa1-xVO3.

The evolution of electron correlation in SrxCa1-xVO3 has been studied using a combination of bulk-sensitive resonant soft x-ray emission spectroscopy, surface-sensitive photoemission spectroscopy, and ab initio band structure calculations. We show that the effect of electron correlation is enhanced at the surface. Strong incoherent Hubbard subbands are found to lie ∼20% closer in energy to the coherent quasiparticle features in surface-sensitive photoemission spectroscopy measurements compared with those from bulk-sensitive resonant soft x-ray emission spectroscopy, and a ∼10% narrowing of the overall bandwidth at the surface is also observed.

Validation of a paternally imprinted QTL affecting pH24h distinct from PRKAG3 on SSC15.

We previously performed a genome scan in a White Duroc × Erhualian F(2) population and identified a QTL on SSC15 with strong effect on pH24h in M. Longissimus dorsi and M. Semimembranous muscle tissue. At that time, the mode of inheritance of this QTL was not clarified, and it was also unclear whether the observed QTL effect was completely or partially caused by mutations in the PRKAG3 gene, which is the only major gene on SSC15 so far known to influence pH24h. In this study, effects of the PRKAG3 gene on meat quality traits were estimated by association analyses. Two substitutions in PRKAG3, p.Ile199Val (p.I199V) and p.Thr30Asn (p.T30N), were found to be segregating in the F(2) population and to significantly affect pH24h and total glycogen in meat, respectively. However, we excluded PRKAG3 as a causative gene for the detected QTL based on the following reasons: (i) the gene was located outside of the QTL confidence interval; (ii) when the PRKAG3 substitution was included as a fixed effect in the QTL model, the F-ratio for the QTL increased rather than decreased; (iii) favourable alleles for pH24h at the QTL and at the PRKAG3 p.I199V locus originated from Erhualian and White Duroc founders, respectively; (iv) more importantly, this QTL showed exclusive maternal expression, differing from the Mendelian expression of PRKAG3. In conclusion, this study is the first to report a maternally-expressed QTL for pH24h on SSC15, which is distinct from PRKAG3.