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1
Santana, Miguel Henrique de Almeida, Paulo Rossi Junior, Rodrigo de Almeida, and Amanda Massaneira de Souza Schuntzemberger. "Blood cell and metabolic profile of Nellore bulls and their correlations with residual feed intake and feed conversion ratio." Revista Brasileira de Saúde e Produção Animal 14, no. 3 (September 2013): 527–37. http://dx.doi.org/10.1590/s1519-99402013000300018.
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Due to the potential metabolic changes related to the residual feed intake (RFI), this study investigated the correlation of traditional RFI (RFI1), RFI adjusted for final rump fat thickness (RFI2) and feed conversion ratio (FCR) with the metabolic and blood profiles, as well as determined the possible different classes of RFI1 and RFI2. For this purpose, 46 Nellore bulls, 22 month-old and 411kg of weight at the beginning of the study were used. The animals were fed with the same diet for 84 days, and blood samples were collected every 21 days for evaluation of serum metabolites and blood cell profiles. No significant correlations were found between FCR and metabolic or blood traits, although there was a significant correlation between RFI1 and urea serum concentration. There were also differences between the RFI classes for creatinine, in which more efficient animals showed higher values. The RFI2 did not correlate with any metabolic and blood cell variable, but young bulls with smaller RFI2 had a smaller number of eosinophils when compared to animals with higher RFI2. These results suggest that animals with a high RFI can have greater energy expenditure due to protein synthesis and degradation process, resulting in a larger blood urea level.
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Santiago, Kier Gumangan, Bryan Irvine Lopez, Sung-Hoon Kim, Dong-Hui Lee, Young-Gyu Cho, Yu-Na Song, and Kang-Seok Seo. "Genetic Parameters for Different Measures of Feed Efficiency and Their Relationship to Production Traits in Three Purebred Pigs." Life 11, no. 8 (August 13, 2021): 830. http://dx.doi.org/10.3390/life11080830.
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Residual feed intake (RFI) gained attention as a potential alternative to the feed conversion ratio (FCR). Thus, this study aimed to estimate genetic parameters for different feed efficiency (FE) traits (FCR, RFI1 to RFI5) and their genetic correlation to on-test daily weight gain (ADG), backfat (BFT), loin muscle area (LMA), lean percentage (LP), and total feed intake (FI) for 603 Male Duroc (DD), 295 Landrace (LL), and 341 Yorkshire (YY). The common spatial pen effect was also estimated in these traits. Five RFI measures were estimated by regressing daily feed intake on initial testing age (ITA), initial testing weight (IBW), and ADG for RFI1; other models were the same as RFI1 except for additional BFT for RFI2; LMA for RFI3; BFT and LMA for RFI4; BFT, LMA, and average metabolic body weight (AMBW) instead of IBW for RFI5. Genetic parameters estimated using two animal models and the REML method showed moderate heritability for FCR in all breeds (0.22 and 0.28 for DD, 0.31 and 0.39 for LL, 0.17 and 0.22 for YY), low heritability for the majority of RFI measures in DD (0.15 to 0.23) and YY (0.14 to 0.20) and moderate heritability for all RFI measures in LL (0.31 to 0.34). Pen variance explained 7% to 22% for FE and 0% to 9% for production traits’ phenotypic variance. The genetic correlation revealed that selection against less complex RFI1 in DD and LL and RFI2 in YY would bring the most advantageous reduction to FI (0.71 for DD, 0.49 for LL, 0.43 YY) without affecting ADG in all breeds (0.06 for DD, −0.11 for LL, 0.05 for YY), decrease in BFT, and increase in LP in DD (0.51 in BFT, −0.77 in LP) and LL (0.45 in BFT, −0.83 in LP). Therefore, inclusion of these breed-specific RFI measures in the future selection criteria would help improve feed efficiency in the swine industry.
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Zhang, Hengrui, Lin Min, Jing Lu, Jike Chang, Zhengwei Guo, and Ning Li. "An Improved RFI Mitigation Approach for SAR Based on Low-Rank Sparse Decomposition: From the Perspective of Useful Signal Protection." Remote Sensing 14, no. 14 (July 7, 2022): 3278. http://dx.doi.org/10.3390/rs14143278.
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As an open system, synthetic aperture radar (SAR) inevitably receives radio frequency interference (RFI) generated by electromagnetic equipment in the same band. The existence of RFI seriously affects SAR signal processing and image interpretation. In recent years, many algorithms and models related to RFI mitigation have been proposed. However, most of that focus on effectively mitigating the RFI is insufficient to protect the useful signals. This article proposes a mitigation method of RFI with a signal-protected capability. (1) The kurtosis coefficient is used to detect RFI pulse-by-pulse, and the echoes containing RFI are stored in matrix form. (2) The preliminary extraction of RFI is complete by low-rank sparse decomposition of the echo matrix containing RFI. (3) For the secondary separation of RFI, the accurate position of RFI in the preliminary extraction results is located by the fuzzy C-means clustering; then, we separate the RFI and the remaining useful signals again and reconstruct the useful signals to complete the mitigation work. The proposed method can further protect useful signals while effectively removing interference through the secondary separation of RFI. Experimental results based on simulated and measured data verify the performance and potential of the proposed method.
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Zhang, Chuan-Peng, Jin-Long Xu, Jie Wang, Yingjie Jing, Ziming Liu, Ming Zhu, and Peng Jiang. "Radio Frequency Interference Mitigation and Statistics in the Spectral Observations of FAST." Research in Astronomy and Astrophysics 22, no. 2 (February 1, 2022): 025015. http://dx.doi.org/10.1088/1674-4527/ac3f2d.
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Abstract In radio astronomy, radio frequency interference (RFI) becomes more and more serious for radio observational facilities. The RFI always influences the search and study of the interesting astronomical objects. Mitigating the RFI becomes an essential procedure in any survey data processing. The Five-hundred-meter Aperture Spherical radio Telescope (FAST) is an extremely sensitive radio telescope. It is necessary to find out an effective and precise RFI mitigation method for FAST data processing. In this work, we introduce a method to mitigate the RFI in FAST spectral observation and make a statistic for the RFI using ∼300 h FAST data. The details are as follows. First, according to the characteristics of FAST spectra, we propose to use the Asymmetrically Reweighted Penalized Least Squares algorithm for baseline fitting. Our test results show that it has a good performance. Second, we flag the RFI with four strategies, which are to flag extremely strong RFI, flag long-lasting RFI, flag polarized RFI, and flag beam-combined RFI, respectively. The test results show that all the RFI above a preset threshold could be flagged. Third, we make a statistic for the probabilities of polarized XX and YY RFI in FAST observations. The statistical results could tell us which frequencies are relatively quiescent. With such statistical data, we are able to avoid using such frequencies in our spectral observations. Finally, based on the ∼300 h FAST data, we obtained an RFI table, which is the most complete database currently for FAST.
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Xie, Yunyi, Chao Miao, Yi Lu, Huizeng Sun, and Jianxin Liu. "Nitrogen metabolism and mammary gland amino acid utilization in lactating dairy cows with different residual feed intake." Animal Bioscience 34, no. 10 (October 1, 2021): 1600–1606. http://dx.doi.org/10.5713/ab.20.0821.
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Objective: This study was conducted to enhance our understanding of nitrogen (N) metabolism and mammary amino acid (AA) utilization in lactating cows with divergent phenotypes of residual feed intake (RFI).Methods: Fifty-three multiparous mid-lactation Holstein dairy cows were selected for RFI measurements over a 50-d experimental period. The 26 cows with the most extreme RFI values were classified into the high RFI (n = 13) and low RFI (n = 13) groups, respectively, for analysis of N metabolism and AA utilization.Results: Compared with the high RFI cows, the low RFI animals had lower dry matter intake (p<0.01) with no difference observed in milk yield between the two groups (p> 0.10). However, higher ratios of milk yield to dry matter intake (p<0.01) were found in the low RFI cows than in the high RFI cows. The low RFI cows had significant greater ratios of milk protein to metabolizable protein (p = 0.02) and milk protein to crude protein intake than the high RFI cows (p = 0.01). The arterial concentration and mammary uptake of essential AA (p<0.10), branched-chain AA (p<0.10), and total AA (p<0.10) tended to be lower in the low RFI cows. Additionally, the low RFI cows tended to have a lower ratio of AA uptake to milk output for essential AA (p = 0.08), branched-chain AA (p = 0.07) and total AA (p = 0.09) than the high RFI cows.Conclusion: In summary, both utilization of metabolizable protein for milk protein and mammary AA utilization are more efficient in cows with lower RFI than in the high RFI cows. Our results provide new insight into the protein metabolic processes (related to N and AA) involved in feed efficiency.
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Prudhomme, Christel, Simon Parry, Jamie Hannaford, Douglas B. Clark, Stefan Hagemann, and Frank Voss. "How Well Do Large-Scale Models Reproduce Regional Hydrological Extremes in Europe?" Journal of Hydrometeorology 12, no. 6 (December 1, 2011): 1181–204. http://dx.doi.org/10.1175/2011jhm1387.1.
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Abstract This paper presents a new methodology for assessing the ability of gridded hydrological models to reproduce large-scale hydrological high and low flow events (as a proxy for hydrological extremes) as described by catalogues of historical droughts [using the regional deficiency index (RDI)] and high flows [regional flood index (RFI)] previously derived from river flow measurements across Europe. Using the same methods, total runoff simulated by three global hydrological models from the Water Model Intercomparison Project (WaterMIP) [Joint U.K. Land Environment Simulator (JULES), Water Global Assessment and Prognosis (WaterGAP), and Max Planck Institute Hydrological Model (MPI-HM)] run with the same meteorological input (watch forcing data) at the same spatial 0.5° grid was used to calculate simulated RDI and RFI for the period 1963–2001 in the same European regions, directly comparable with the observed catalogues. Observed and simulated RDI and RFI time series were compared using three performance measures: the relative mean error, the ratio between the standard deviation of simulated over observed series, and the Spearman correlation coefficient. Results show that all models can broadly reproduce the spatiotemporal evolution of hydrological extremes in Europe to varying degrees. JULES tends to produce prolonged, highly spatially coherent events for both high and low flows, with events developing more slowly and reaching and sustaining greater spatial coherence than observed—this could be due to runoff being dominated by slow-responding subsurface flow. In contrast, MPI-HM shows very high variability in the simulated RDI and RFI time series and a more rapid onset of extreme events than observed, in particular for regions with significant water storage capacity—this could be due to possible underrepresentation of infiltration and groundwater storage, with soil saturation reached too quickly. WaterGAP shares some of the issues of variability with MPI-HM—also attributed to insufficient soil storage capacity and surplus effective precipitation being generated as surface runoff—and some strong spatial coherence of simulated events with JULES, but neither of these are dominant. Of the three global models considered here, WaterGAP is arguably best suited to reproduce most regional characteristics of large-scale high and low flow events in Europe. Some systematic weaknesses emerge in all models, in particular for high flows, which could be a product of poor spatial resolution of the input climate data (e.g., where extreme precipitation is driven by local convective storms) or topography. Overall, this study has demonstrated that RDI and RFI are powerful tools that can be used to assess how well large-scale hydrological models reproduce large-scale hydrological extremes—an exercise rarely undertaken in model intercomparisons.
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Ding, Yi, Weiwei Fan, Zijing Zhang, Feng Zhou, and Bingbing Lu. "Radio Frequency Interference Mitigation for Synthetic Aperture Radar Based on the Time-Frequency Constraint Joint Low-Rank and Sparsity Properties." Remote Sensing 14, no. 3 (February 7, 2022): 775. http://dx.doi.org/10.3390/rs14030775.
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Synthetic aperture radar (SAR) is susceptible to radio frequency interference (RFI), which becomes especially commonplace in the increasingly complex electromagnetic environments. RFI severely detracts from SAR imaging quality, which hinders image interpretation. Therefore, some RFI mitigation algorithms have been introduced based on the partial features of RFI, but the RFI reconstruction models in these algorithms are rough and can be improved further. This paper proposes two algorithms for accurately modeling the structural properties of RFI and target echo signal (TES). Firstly, an RFI mitigation algorithm joining the low-rank characteristic and dual-sparsity property (LRDS) is proposed. In this algorithm, RFI is treated as a low-rank and sparse matrix, and the sparse matrix assumption is made for TES in the time–frequency (TF) domain. Compared with the traditional low-rank and sparse models, it can achieve better RFI mitigation performance with less signal loss and accelerated algorithm convergence. Secondly, the other RFI mitigation algorithm, named as TFC-LRS, is proposed to further reduce the signal loss. The TF constraint concept, in lieu of the special sparsity, is introduced in this algorithm to describe the structural distribution of RFI because of its aggregation characteristic in the TF spectrogram. Finally, the effectiveness, superiority, and robustness of the proposed algorithms are verified by RFI mitigation experiments on the simulated and measured SAR datasets.
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Cohen-Zinder, Miri, Aviv Asher, Ehud Lipkin, Roi Feingersch, Rotem Agmon, David Karasik, Arieh Brosh, and Ariel Shabtay. "FABP4is a leading candidate gene associated with residual feed intake in growing Holstein calves." Physiological Genomics 48, no. 5 (May 2016): 367–76. http://dx.doi.org/10.1152/physiolgenomics.00121.2015.
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Ecological and economic concerns drive the need to improve feed utilization by domestic animals. Residual feed intake (RFI) is one of the most acceptable measures for feed efficiency (FE). However, phenotyping RFI-related traits is complex and expensive and requires special equipment. Advances in marker technology allow the development of various DNA-based selection tools. To assimilate these technologies for the benefit of RFI-based selection, reliable phenotypic measures are prerequisite. In the current study, we identified single nucleotide polymorphisms (SNPs) associated with RFI phenotypic consistency across different ages and diets (named RFI 1–3), using DNA samples of high or low RFI ranked Holstein calves. Using targeted sequencing of chromosomal regions associated with FE- and RFI-related traits, we identified 48 top SNPs significantly associated with at least one of three defined RFIs. Eleven of these SNPs were harbored by the fatty acid binding protein 4 ( FABP4). While 10 significant SNPs found in FABP4 were common for RFI 1 and RFI 3, one SNP (FABP4_5; A<G substitution), in the promoter region of the gene, was significantly associated with all three RFIs. As the three RFI classes reflect changing diets and ages with concomitant RFI phenotypic consistency, the above polymorphisms and in particular FABP4_5, might be considered possible markers for RFI-based selection for FE in the Holstein breed, following a larger-scale validation.
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Oliveira, L. F., A. C. Ruggieri, R. H. Branco, O. L. Cota, R. C. Canesin, H. J. U. Costa, and M. E. Z. Mercadante. "Feed efficiency and enteric methane production of Nellore cattle in the feedlot and on pasture." Animal Production Science 58, no. 5 (2018): 886. http://dx.doi.org/10.1071/an16303.
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The objective of the present study was to assess the relationship between residual feed intake (RFI) evaluated in a feedlot-performance test and on pasture, and to determine the effect of feedlot RFI classification on enteric methane (CH4) production in the feedlot and on pasture. Seventy-three animals (25 with a low RFI, 24 with a medium RFI and 24 with a high RFI) classified in a feedlot performance test were subjected to performance testing on Brachiaria brizantha cv. Marandu pasture. Enteric CH4 was measured in a sample of these animals (n = 47, with high and low RFI) by the sulfur hexafluoride tracer-gas technique after the feedlot-performance test and during the performance test on pasture. In the feedlot-performance test, dry-matter intake (DMI) of low-RFI animals was 9.4% and 19.7% lower (P < 0.05) than that of medium- and high-RFI animals respectively. However, there was no difference in DMI and, consequently, in RFI on pasture among animals classified as low, medium and high RFI. Accordingly, there is evidence of re-ranking of animals for RFI performance tested in the feedlot after weaning and, subsequently, on pasture. During the period of enteric CH4 measurement in the feedlot and on pasture, the DMI, neutral detergent-fibre intake and gross-energy intake of low-RFI animals were lower than those of high-RFI animals, and low-RFI animals exhibited greater DM and neutral detergent fibre digestibility only in the feedlot. Enteric CH4 production did not differ between low- and high-RFI animals either in the feedlot (101 and 107 g CH4/day) or on pasture (101 and 95.9 g CH4/day). A significant difference in CH4 yield (CH4/kg DMI) was observed on pasture between animals with low and high RFI (17.6 and 13.7 g CH4/kg DMI respectively). The results did not support the hypothesis that an increase in feed efficiency, evaluated in growing animals in feedlot-performance tests, decreases enteric CH4 production (g/day) proportionally to the lower DMI.
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Holló, Gabriella, Henrietta Nagy-Kiszlinger, János Tossenberger, Márton Török, and Balázs Húth. "Individual Feed Efficiency Monitoring of Charolaise Candidate Young Bulls in Relation to Feeding Behavior and Self-Performance Test Results." Animals 12, no. 1 (December 24, 2021): 35. http://dx.doi.org/10.3390/ani12010035.
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This study evaluated the effect of differences in residual feed intake (RFI) of Charolaise candidate young bulls on feeding behavior and self-performance test results. Bulls were classified into high and low RFI (H-RFI, L-RFI) groups. Bulls were fed in a HOKOFARM system to measure individual animal intake and behavior. L-RFI bulls had significantly lower feed intakes (p = 0.002) and higher gain to feed ratio (p = 0.001), lower intake per day/kg DM (dry matter) (p = 0.002) and lower intake g/body weight/day (p < 0.001). L-RFI animals had lower visits number per day (p = 0.02), but spent longer time per visit (p = 0.02), and tended to have higher intake g/visit (p = 0.06) on feeders. The correlation between RFI and DMI (dry matter intake)/bodyweight/day as well as intake per day/kg were large and positive. Back-loin length and rump length, and moreover muzzle width and frame, showed negative correlations with RFI value. However, bulls with better RFI values associated with lower legs score. Results reveal that RFI was shown beneficial correlations with economically relevant self-performance traits. Further investigations are needed to seek additional indicator traits that are predictive for RFI.
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Taiwo, Godstime A., Modoluwamu Idowu, Andres a. Pech-Cervantes, Zaira M. Estrada-Reyes, and Ibukun M. Ogunade. "PSVII-20 Hepatic Mrna Expression of Nutrient and Mitochondrial Energy Metabolism Genes in Beef Steers Selected for low or High Residual Feed Intake." Journal of Animal Science 100, Supplement_3 (September 21, 2022): 384. http://dx.doi.org/10.1093/jas/skac247.702.
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Abstract We evaluated the mRNA expression of genes involved in hepatic fatty acid, amino acid, and mitochondrial energy metabolism in crossbred beef steers with divergent low and high residual feed intake (RFI). Low-RFI beef steers (n = 8; RFI = - 1.93 kg/d) and high-RFI beef steers (n = 8; RFI = + 2.01kg/d) were selected from a group of 56 growing crossbred beef steers (average BW = 261 ± 18.5 kg) after a 49-d performance testing period. At the end of the 49-d period, liver biopsies were collected from the low-RFI and high-RFI beef steers for RNA extraction and cDNA synthesis. The mRNA expression of 84 genes each related to fatty acid metabolism, amino acid metabolism, and mitochondrial energy metabolism were analyzed using pathway-focused PCR-based arrays. The mRNA expression of genes with absolute fold change (FC) ≥ 2.0 having false discovery rate-adjusted P-values (FDR) ≤ 0.05 were considered to be differentially expressed. Eight genes (CRAT, SLC27A5, SLC27A2, ACSBG2, ACADL, ACADSB, ACAA1, and ACAA2) involved fatty acid transport and β-oxidation were upregulated in low-RFI, compared with high-RFI steers. Hepatic mRNA expression of a gene encoding for aminoadipate aminotransferase, an enzyme related to lysine degradation, was downregulated (FC = -5.45, P = 0.01) in low-RFI steers, whereas those of methionine adenosyltransferase I and aspartate aminotransferase 2, which both link amino acid and lipid metabolism, were upregulated. Two mitochondrial energy metabolism genes (UQCRC1 and ATP5G1) involved in ATP synthesis via oxidative phosphorylation were upregulated in low-RFI beef steers, compared with high-RFI beef steers. The results of this study demonstrated that low-RFI beef steers exhibit upregulation of molecular mechanisms related to fatty acid transport, fatty acid β-oxidation, and mitochondrial ATP synthesis, which suggest that low-RFI beef steers have enhanced metabolic capacity to maximize capture of energy and nutrients from feeds consumed.
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Taiwo, Godstime A., Modoluwamu Idowu, Mata Padrino Domingo Jose, James Denvir, and Ibukun M. Ogunade. "PSIX-16 Urine Metabolome and Whole Blood Transcriptome of Beef Steers with low or High Residual Feed Intake." Journal of Animal Science 100, Supplement_3 (September 21, 2022): 372. http://dx.doi.org/10.1093/jas/skac247.680.
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Abstract We analyzed the metabolome of urine samples to identify urinary metabolic biomarkers and whole blood transcriptome-based gene set enrichment to identify key pathways associated with divergent selection for low or high RFI in beef cattle. Low-RFI beef steers (n = 8; RFI = - 1.93 kg/d) and high-RFI beef steers (n = 8; RFI = + 2.01kg/d) were selected from a group of 56 growing crossbred beef steers after a 49-d performance testing period. At the end of the 49-d period, weekly urine and blood samples were collected three times from the low- and high-RFI steers. Metabolome analysis of the urine samples was conducted using a liquid chromatography–mass spectrometer and biomarker analysis of the metabolome data was performed to identify candidate biomarkers (FDR ≤ 0.05; AUC ≥ 0.85) associated with RFI. Whole-blood RNA sequencing was performed on an Illumina sequencer and gene set enrichment analysis (GSEA) was used to analyze differentially expressed (FDR ≤ 0.05) pathways. A total number of 557 metabolites were detected and identified. Biomarker analysis of the metabolome data identified N-acetyl-L-tyrosine, O-methyl-L-threonine, uridine, and threoninyl-hydroxyproline as candidate biomarkers (FDR ≤ 0.05; AUC > 0.85) of RFI. Results of GSEA revealed pathways associated with protein metabolism, cellular responses to external stimuli, and stress were differentially inhibited in high-RFI compared with low-RFI beef cattle, while pathways associated with binding and uptake of ligands by scavenger receptors and erythrocytes release/take up oxygen were differentially enriched (FDR < 0.05) in high-RFI beef steers. Taken together, our results revealed that urine is a potential source of metabolite biomarkers associated with RFI and beef steers divergently selected for low or high RFI have differential expressions of genes related to protein metabolism and stress responsiveness. high RFI revealed differential expressions of genes related to protein metabolism and stress responsiveness.
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Lines, D. S., W. S. Pitchford, C. D. K. Bottema, R. M. Herd, and V. H. Oddy. "Selection for residual feed intake affects appetite and body composition rather than energetic efficiency." Animal Production Science 58, no. 1 (2018): 175. http://dx.doi.org/10.1071/an13321.
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Residual feed intake (RFI) is the difference between an animal’s actual feed intake and that which would be expected based on production. This experiment was to test the hypothesis that part of the variation in RFI may be due to differences in energetic efficiency through changes in heat production, these being in part due to differences in protein metabolism. Following three generations of divergent selection for RFI, eight High and eight Low-RFI heifers were fed at both 105% and 180% of predicted maintenance feed requirements. Between-RFI line and feeding-level differences were assessed for energy intake, protein metabolism, heat production, body composition, energy and nitrogen balance and digestibility. The RFI lines did not differ in protein metabolism or heat production. The High-RFI heifers deposited 51% and 56% more subcutaneous fat at the P8 rump and 12/13th rib sites, respectively, with no difference in eye muscle area gain or average daily weight gain. The greater fat deposition of High-RFI heifers was due to a larger ad libitum feed consumption compared with the Low-RFI heifers. Energy and nitrogen balance did not differ between the RFI lines. The energy transactions indicated no difference in the efficiency of energy use on 105% maintenance, although when fed 180% of maintenance the differences in feed intake suggest variation in appetite as the mechanism contributing to RFI. All of the extra energy consumed by High-RFI heifers above maintenance and deposition of protein was associated with additional energy retained as fat. This study suggests that selection for RFI may not lead to improved efficiency of energy use.
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REIS, Simone Frotas dos, Daiane Aparecida FAUSTO, Sergio Raposo de MEDEIROS, Pedro Veiga Rodrigues PAULINO, Sebastião de Campos VALADARES FILHO, and Roberto Augusto de Almeida TORRES JÚNIOR. "Feed efficiency and meat quality of crossbred beef heifers classified according to residual feed intake." Revista Brasileira de Saúde e Produção Animal 16, no. 3 (September 2015): 632–42. http://dx.doi.org/10.1590/s1519-99402015000300014.
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AbstractThis study aimed to evaluate feed efficiency and meat quality of 31 three-crossbred beef heifers during 84 days in a feedlot system. A 60:40 concentrate and sorghum silage ration on DM basis (ME = 2.73Mcal/kg of DM, CP = 11.90% DM) was fed ad libitum. Based on residual feed intake (RFI) calculations, the heifers were ranked in three groups of feed efficiency: High RFI (average mean = 0.776; n = 9), medium RFI (average mean = -0.010; n = 11), and low RFI (average mean = - 0.624; n = 11). High RFI heifers consumed 4.56% more DM per day than low RFI heifers (P <0.05). The ADG did not differ (P> 0.05) among RFI groups (1.40kg/day). No differences (P>0.05) were detected for digestibility of the nutrients: DM (64.00%), CP (60.01%), crude fat (72.90%), NDF (54.80%) and non-fibrous carbohydrate (NFC) (78.91%). There were no differences between low and high RFI groups for slaughter weight (475.00 vs. 479.55kg), hot carcass weight (259.09 vs. 261.44kg), Longissimus dorsi (LD) area (69.02 vs. 68.11 cm2), back-fat thickness (5.74 vs. 6.26 cm), shear force (5.45 vs. 5.19kg), sensorial traits of LD muscle, LD color (intensities L=40.47 a*=24.74 and b*=16.13) or commercial cuts yield. Low RFI heifers presented similar meat quality and carcass traits as high RFI heifers, however low RFI heifers consumed less DM (kg/d).
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Basnet, Pawan, Sharon A. Clay, and Emmanuel Byamukama. "Reproduction of Soybean Cyst Nematode Populations on Field Pennycress, Henbit, and Purple Deadnettle Weed Hosts." Agronomy 12, no. 9 (August 26, 2022): 2027. http://dx.doi.org/10.3390/agronomy12092027.
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Several weeds serve as alternative soybean cyst nematode (SCN) hosts. Still, the relative reproductive capacity of SCN HG types (Heterodera glycines type) on weed hosts relative to soybean is not well understood. This study examined the reproduction of three South Dakota endemic SCN populations—PSCN-1 (HG 0), PSCN-2 (HG 2.5.7), and PSCN-3 (HG 7)—on purple deadnettle, field pennycress, and henbit. The Relative Female Index (RFI) was calculated to compare SCN reproduction relative to the susceptible soybean check. Weed hosts, HG types, and their interactions influenced SCN reproduction. Henbit (RFI = 51.8) and purple deadnettle (RFI = 47.6) roots had a similar high RFI, whereas field pennycress (RFI = 23.04) had a lower RFI. Similarly, SCN populations PSCN-1 and PSCN-3 had a similar RFI of 36.9 and 37.2, respectively, while the population PSCN-2 had a higher RFI of 44.9 across weed hosts. A significant interaction between PSCN-1 and purple deadnettle was observed where the RFI was the highest (RFI = 53.3). These results indicate that these weed hosts support endemic SCN populations, and the HG type influenced reproductive success, further complicating SCN management. Hence, SCN presents a significant challenge in the new prospect of incorporating field pennycress host as an oilseed cover crop in the Midwest’s corn–soybean production system.
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Acetoze, G., K. L. Weber, J. J. Ramsey, and H. A. Rossow. "Relationship between Liver Mitochondrial Respiration and Proton Leak in Low and High RFI Steers from Two Lineages of RFI Angus Bulls." International Scholarly Research Notices 2015 (April 23, 2015): 1–5. http://dx.doi.org/10.1155/2015/194014.
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The objective of this research is to evaluate liver mitochondrial oxygen consumption and proton leak kinetics in progeny from two lineages of Angus bulls with high and low residual feed intake (RFI). Two Angus bulls were selected based on results from a genetic test for RFI and were used as sires. Eight offspring at 10-11 months of age from each sire were housed in individual pens for 70–105 days following a diet adaptation period of 14 days. Progeny of the low RFI sire had 0.57 kg/d (P=0.05) lower average RFI than progeny of the high RFI sire. There was no difference in dry matter intake between low and high RFI steers, but low RFI steers gained more body weight (P=0.02) and tended to have higher average daily gains (P=0.07). State 3 and State 4 respiration, RCR, and proton leak did not differ between high and low RFI steers (P=0.96, P=0.81, P=0.93, and P=0.88, resp.). Therefore, the increase in bodyweight gain which distinguished the low RFI steers from the high RFI steers may be associated with other metabolic mechanisms that are not associated with liver mitochondrial respiration and proton leak kinetics.
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Wu, Ying, Bo Qian, Yansong Bao, Meixin Li, George P. Petropoulos, Xulin Liu, and Lin Li. "Detection and Analysis of C-Band Radio Frequency Interference in AMSR2 Data over Land." Remote Sensing 11, no. 10 (May 23, 2019): 1228. http://dx.doi.org/10.3390/rs11101228.
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A simplified generalized radio frequency interference (RFI) detection method and principal component analysis (PCA) method are utilized to detect and attribute the sources of C-band RFI in AMSR2 L1 brightness temperature data over land during 1–16 July 2017. The results show that the consistency between the two methods provides confidence that RFI may be reliably detected using either of the methods, and the only difference is that the scope of the RFI-contaminated area identified by the former algorithm is larger in some areas than that using the latter method. Strong RFI signals at 6.925 GHz are mainly distributed in the United States, Japan, India, Brazil, and some parts of Europe; meanwhile, RFI signals at 7.3 GHz are mainly distributed in Latin America, Asia, Southern Europe, and Africa. However, no obvious 7.3 GHz RFI appears in the United States or India, indicating that the 7.3 GHz channels mitigate the effects of the C-band RFI in these regions. The RFI signals whose position does not vary with the Earth azimuth of the observations generally come from stable, continuous sources of active ground-based microwave radiation, while the RFI signals which are observed only in some directions on a kind of scanning orbit (ascending/descending) mostly arise from reflected geostationary satellite signals.
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Johnson, Chinju, Carolyn Fitzsimmons, Marcos Colazo, Changxi Li, John Kastelic, and Jacob Thundathil. "Impacts of residual feed intake and pre-natal diet on reproductive potential of bulls." Animal Production Science 59, no. 10 (2019): 1827. http://dx.doi.org/10.1071/an18301.
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Our objective was to determine effects of genetic potential for residual feed intake (RFI) and pre-natal diet on post-natal growth and reproductive development of bulls. Twenty-five bull calves with a divergent potential for RFI were produced by mating purebred Angus heifers (60) categorised as high or low RFI and inseminated with semen from high or low RFI bulls. From 30 to 150 days of gestation, half the heifers (balanced for RFI across treatments) in each RFI category were fed to gain 0.7 or 0.5 kg/day (~100% and 75% of recommended feed intake; designated normal- and low-diet, respectively). Birthweights of bull calves (n = 25) did not differ significantly among treatment groups (P ≥ 0.1). However, there was a tendency (P < 0.1) for a maternal diet*time interaction for bull weights, with bulls from low pre-natal diet fed heifers growing faster between 10 and 16 months of age than bulls from normal pre-natal diet fed heifers. Furthermore, high-RFI bulls had a larger scrotal circumference (P < 0.01) and attained puberty (P < 0.05) earlier than low-RFI bulls. Other testes measures, including paired testes volume, epididymal sperm reserves, daily sperm production and total sperm production, were not significantly different among treatment groups (P ≥ 0.1). High RFI bulls tended (P < 0.1) to have better average sperm motility than low RFI bulls. However, sperm morphology, viability and chromatin damage were not different (P ≥ 0.1). In summary, young beef bulls with low RFI had smaller testis, delayed onset of puberty (~1.7 months) and tended to exhibit lower progressive motility compared with high RFI bulls. Pre-natal diet had no direct influence on male reproductive development, nor did it interact with RFI of bulls.
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Yang, Zhicheng, Ce Yu, Jian Xiao, and Bo Zhang. "Deep residual detection of radio frequency interference for FAST." Monthly Notices of the Royal Astronomical Society 492, no. 1 (January 11, 2020): 1421–31. http://dx.doi.org/10.1093/mnras/stz3521.
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ABSTRACT Radio frequency interference (RFI) detection and excision are key steps in the data-processing pipeline of the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Because of its high sensitivity and large data rate, FAST requires more accurate and efficient RFI flagging methods than its counterparts. In the last decades, approaches based upon artificial intelligence (AI), such as codes using convolutional neural networks (CNNs), have been proposed to identify RFI more reliably and efficiently. However, RFI flagging of FAST data with such methods has often proved to be erroneous, with further manual inspections required. In addition, network construction as well as preparation of training data sets for effective RFI flagging has imposed significant additional workloads. Therefore, rapid deployment and adjustment of AI approaches for different observations is impractical to implement with existing algorithms. To overcome such problems, we propose a model called RFI-Net. With the input of raw data without any processing, RFI-Net can detect RFI automatically, producing corresponding masks without any alteration of the original data. Experiments with RFI-Net using simulated astronomical data show that our model has outperformed existing methods in terms of both precision and recall. Besides, compared with other models, our method can obtain the same relative accuracy with fewer training data, thus reducing the effort and time required to prepare the training data set. Further, the training process of RFI-Net can be accelerated, with overfittings being minimized, compared with other CNN codes. The performance of RFI-Net has also been evaluated with observing data obtained by FAST and the Bleien Observatory. Our results demonstrate the ability of RFI-Net to accurately identify RFI with fine-grained, high-precision masks that required no further modification.
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BABAN, BHONG N., CHANDER DATT, PH SURAJ SHARMA, KULDEEP DUDI, and VIJAY K. SHARMA. "Residual feed intake and related biochemical parameters in male Sahiwal calves." Indian Journal of Animal Sciences 90, no. 10 (April 5, 2021): 1423–29. http://dx.doi.org/10.56093/ijans.v90i10.111420.
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This study was conducted to evaluate the differences in efficiency of feed utilisation in Sahiwal calves with low and high residual feed intake (RFI) by comparing feed intake, nutrient digestibility, growth traits and blood biochemical parameters. Eighteen growing male Sahiwal calves (aged 12 months, average body weight 120.04 kg) were selected and fed individually total mixed ration as per their requirements for a period of 60 days. Fifty per cent of maize grains in concentrate mixture containing 33% maize grains were replaced by fresh potatoes (DM basis). Based on linear regression models involving dry matter intake (DMI), average daily gain (ADG) and mid test metabolic body size, calves were assigned into low and high RFI groups. Residual feed intake (RFI) values were calculated for individual calves and the calves were divided into low (–0.20) and high (+0.18) RFI groups. Low RFI animals consumed less dry matter than the expected or predicted one indicating their more efficiency of feed utilization. The intakes of DM and CP were 4.95 and 6.47% lower in low RFI animals compared to high RFI animals while average daily gain was higher in low RFI group. The digestibility of DM, OM, CP, EE, total carbohydrates, NDF and ADF were similar in low and high RFI groups, however, nitrogen retention was higher in low RFI group. Values of alanine amino transferase (25.85 vs. 35.72 IU/L), aspartate amino transferase (80.33 vs. 100.57 IU/L), total protein (7.34 and 8.24 mg/dL), blood urea nitrogen (15.45 and 22.22 mg/dL) and creatinine (1.27 and 1.78 mg/dL) were higher for high RFI as compared to low RFI group. The concentration of growth hormone, insulin and IGF-1 were similar in both the groups. From present study, it could be concluded that low RFI animals were more efficient in feed conversion.
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Silvestre, Antonio M., Ana Carolina J. Pinto, Werner F. Schleifer, Lidiane S. Miranda, Leandro A. F. Silva, Daniel M. Casali, Katia L. R. Souza, et al. "Relationships of the Microbial Communities with Rumen Epithelium Development of Nellore Cattle Finished in Feedlot Differing in Phenotypic Residual Feed Intake." Animals 12, no. 7 (March 24, 2022): 820. http://dx.doi.org/10.3390/ani12070820.
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The objective of this study was to examine the relationships among ruminal microbial community, rumen morphometrics, feeding behavior, feedlot performance, and carcass characteristics of Nellore cattle, classified by residual feed intake (RFI). Twenty-seven Nellore yearling bulls with an initial body weight (BW) of 423.84 ± 21.81 kg were fed in feedlot for 107 d in individual pens to determine the RFI phenotype. Bulls were categorized as high RFI (>0.5 SD above the mean, n = 8), medium RFI (±0.5 SD from the mean, n = 9), and low RFI (<0.5 SD below the mean, n = 10). At harvest, whole rumen content samples were collected from each bull to evaluate ruminal microbial community, including bacteria and protozoa. The carcass characteristics were determined by ultrasonography at the beginning and at the end of the experimental period, and behavior data were collected on d 88. As a result of ranking Nellore bulls by RFI, cattle from low-RFI group presented lesser daily dry matter intake (DMI), either in kilograms (p < 0.01) or as percentage of BW (p < 0.01) than high-RFI yearling bulls, resulting in improved gain:feed (G:F). However, variables, such as average daily gain (ADG), final BW, hot carcass weight (HCW) and other carcass characteristics did not differ (p > 0.05) across RFI groups. The eating rate of either dry matter (DM )(p = 0.04) or neutral detergent fiber (NDF) (p < 0.01) was slower in medium-RFI yearling bulls. For ruminal morphometrics an RFI effect was observed only on keratinized layer thickness, in which a thinner layer (p = 0.04) was observed in low-RFI Nellore yearling bulls. Likewise, Nellore yearling bulls classified by the RFI did not differ in terms of Shannon’s diversity (p = 0.57) and Chao richness (p = 0.98). Our results suggest that the differences in feed efficiency of Nellore bulls differing in phenotypic RFI should be attributed to metabolic variables other than ruminal microorganisms and epithelium, and deserves further investigation.
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Yu, Junfei, Jingwen Li, Bing Sun, Yuming Jiang, and Liying Xu. "Multiple RFI Sources Location Method Combining Two-Dimensional ESPRIT DOA Estimation and Particle Swarm Optimization for Spaceborne SAR." Remote Sensing 13, no. 6 (March 22, 2021): 1207. http://dx.doi.org/10.3390/rs13061207.
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Synthetic aperture radar (SAR) systems are susceptible to radio frequency interference (RFI). The existence of RFI will cause serious degradation of SAR image quality and a huge risk of target misjudgment, which makes the research on RFI suppression methods receive widespread attention. Since the location of the RFI source is one of the most vital information for achieving RFI spatial filtering, this paper presents a novel location method of multiple independent RFI sources based on direction-of-arrival (DOA) estimation and the non-convex optimization algorithm. It deploys an L-shaped multi-channel array on the SAR system to receive echo signals, and utilizes the two-dimensional estimating signal parameter via rotational invariance techniques (2D-ESPRIT) algorithm to estimate the positional relationship between the RFI source and the SAR system, ultimately combines the DOA estimation results of multiple azimuth time to calculate the geographic location of RFI sources through the particle swarm optimization (PSO) algorithm. Results on simulation experiments prove the effectiveness of the proposed method.
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Dyson, T., H. C. Chiang, E. Egan, N. Ghazi, T. Ménard, R. A. Monsalve, T. Moso, J. Peterson, J. L. Sievers, and S. Tartakovsky. "Radio-Frequency Interference at the McGill Arctic Research Station." Journal of Astronomical Instrumentation 10, no. 02 (May 12, 2021): 2150007. http://dx.doi.org/10.1142/s2251171721500070.
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The frequencies of interest for redshifted 21[Formula: see text]cm observations are heavily affected by terrestrial radio-frequency interference (RFI). We identify the McGill Arctic Research Station (MARS) as a new RFI-quiet site and report its RFI occupancy using 122[Formula: see text]h of data taken with a prototype antenna station developed for the Array of Long-Baseline Antennas for Taking Radio Observations from the Sub-Antarctic. Using an RFI flagging process tailored to the MARS data, we find an overall RFI occupancy of 1.8% averaged over 20–125[Formula: see text]MHz. In particular, the FM broadcast band (88–108[Formula: see text]MHz) is found to have an RFI occupancy of at most 1.6%. The data were taken during the Arctic summer, when degraded ionospheric conditions and an active research base contributed to increased RFI. The results quoted here therefore represent the maximum-level RFI environment at MARS.
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Wu, Ying, Meixin Li, Yansong Bao, and George P. Petropoulos. "Cross-Validation of Radio-Frequency-Interference Signature in Satellite Microwave Radiometer Observations over the Ocean." Remote Sensing 12, no. 20 (October 19, 2020): 3433. http://dx.doi.org/10.3390/rs12203433.
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Radio-frequency-interference (RFI) signals have gradually become a more serious problem in active and passive microwave remote sensing. However, currently, there is no reliable RFI source distribution data to evaluate the accuracy of existing RFI identification methods. In this study, a simplified generalized RFI detection method (GRDM) is proposed to detect RFI applied to the ocean surface. Two RFI detection methods, the GRDM and the double-principal component analysis (DPCA) method, are used for cross-validation to obtain RFI recognition thresholds of DPCA in the Advanced Microwave Scanning Radiometer 2 (AMSR2) ocean data. In addition, in the present work the source and distribution characteristics of RFI over the ocean surface are also analyzed. The results show that the proposed scheme can effectively identify RFI signals from AMSR2 data, and only 7.3, 10.65, and 18.7 GHz channels are contaminated by RFI over the ocean surface. There are strong 7.3 GHz interference signals over the waters of East Asia (with the value of ΔTBH mostly between 5 and 30 K and ΔTBv mostly between 5 and 40 K), Europe (with the value of ΔTBH mostly between 5 and 40 K and ΔTBv mostly between 5 and 30 K), and North America (with the value of ΔTBH mostly between 5 and 50 K and ΔTBv mostly between 5 and 30 K). The RFI signals in 10.65 GHz data are mainly distributed over the Mediterranean and other European waters (with the value of ΔTBH mostly between 5 and 35 K and ΔTBv mostly between 5 and 20 K). The RFI signals at 18.7 GHz are mainly present over the offshore marine areas of North America (with the value of ΔTBH mostly between 5 and 50 K and ΔTBv mostly between 5 and 40 K), with the strongest RFI distributed near the Great Lakes of America, and the RFI magnitudes over the east and west coasts are stronger than over the south coast. Satellite-borne microwave observations over the ocean suffer from interference mainly from stationary communication/television satellites. Due to the reflection of the sea surface, the range and intensity of RFI are strongly dependent on the relative geometric positions of stationary satellites and space-borne passive instruments. Therefore, RFI coverage area changes every day over the ocean in one 16-day period, which is very different from that over the land.
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Wang, Lei, Tao Wang, Qian Peng, Wei Li, Yin Zhou, and Qiang Hao. "SFGPR RFI Suppression Using Wavelet Packet Selective Algorithm." Advanced Materials Research 433-440 (January 2012): 4409–14. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.4409.
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This paper presents a wavelet packet selective algorithm to suppress the radio frequency interference (RFI) in the step-frequency ground-penetrating radar (SFGPR). Based on the property and the form of RFI in the frequency domain of radar echo, the methods of RFI suppression are studied, and the new algorithm is proposed. Using the new algorithm to suppress the RFI in experimental GPR data, the result of the experimentation shows that the algorithm can effectively suppress the RFI in SFGPR. Finally, the performance of the algorithm is analyzed and evaluated. Compared with the median filter algorithm, the ability of the new algorithm to suppress the RFI is significantly improved.
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Bezerra, Bruna Suellen Borges Resende, Mariana Mundim Alves Gomes, Danilo Rodrigues Boaventura, Aline Maria Soares Ferreira, Egleu Diomedes Marinho Mendes, and Carina Ubirajara De Faria. "Phenotypic association between residual feed intake and carcass traits of young nelore bulls." Bioscience Journal 37 (December 29, 2021): e37081. http://dx.doi.org/10.14393/bj-v37n0a2021-48077.
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The purpose of this study was to estimate the phenotypic associations between residual food intake (RFI) and carcass traits, evaluated by ultrasonography, of young Nellore bulls. Information about 53 young Nelore bulls, pure origin (PO), participants in the Individual Performance Test of Nelore Bulls, carried out at the Capim Branco experimental farm of the Federal University of Uberlândia (UFU) were used for this purpose. It was evaluated the characteristics of residual feed intake (RFI), rib eye area (REA), marbling (MAR) and fat thickness (FT). In order to estimate the Spearman and Pearson correlation coefficients, the SAS program was used. Regarding the influence of the RFI classes (low RFI, medium RFI and high RFI) on carcass traits, an out analysis of variance was carried out using the least squares method. It was verified that there was no phenotypic association between RFI and the characteristics of REA and MAR, but the relation between FT and the phenotypic association revealed a medium magnitude. However, when evaluating the RFI classes, it was observed that there were no significant differences of the RFI classes with the carcass traits (REA, FT and MAR). It is recommended that new studies are carried out to verify if the selection for RFI does not result in damages to the finishing of carcass in Nelore cattle.
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Yun, Youngsun, Changdon Kee, Jason Rife, Ming Luo, Sam Pullen, and Per Enge. "Detecting RFI Through Integrity Monitoring at a DGPS Reference Station." Journal of Navigation 59, no. 3 (August 23, 2006): 403–22. http://dx.doi.org/10.1017/s0373463306003882.
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Because GPS is a radio navigation system which has a very low power level, it is vulnerable to RFI. Excessive RFI could cause receiver performance degradation, such as degradation of position accuracy, loss of lock and increased acquisition time. After GPS modernization plans introduce dual-frequency civil signals to mitigate ionospheric errors, RFI will remain as one of the dominant threats for differential GPS navigation systems. Examples of safety-critical civil aviation and military missions threatened by RFI include the Local Area Augmentation System (LAAS) and the Joint Precision Approach and Landing System (JPALS). This paper focuses on RFI mitigation through integrity monitoring for a DGPS system like LAAS or JPALS. The mitigation strategy consists of two parts. First, the paper develops a new RFI detection method, using a raw divergence statistic. Second, the paper investigates strategies for maintaining integrity in the case that RFI is detected.To validate the utility of the divergence-based RFI monitor, this paper takes an experimental approach. The experiments assess the performance of the divergence metric and compare it to existing alternatives for RFI detection, such as metrics for Automatic Gain Control (AGC) and carrier-to-noise ratio (C/N0). Generating a monitoring threshold for these statistics proves challenging, because the threshold depends both on the type of RFI threat (e.g. continuous wave, narrow band, wideband, pulsed) and on environmental conditions, such as temperature. As experiments illustrate, the divergence statistic resolves these limitations, as divergence directly estimates ranging source error, independent of the type of RFI threat or the environmental conditions.
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Deshpande, Avinash A., and B. M. Lewis. "Iridium Satellite Signals: A Case Study in Interference Characterization and Mitigation for Radio Astronomy Observations." Journal of Astronomical Instrumentation 08, no. 01 (March 2019): 1940009. http://dx.doi.org/10.1142/s2251171719400099.
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Several post-detection approaches to the mitigation of radio-frequency interference (RFI) are compared by applying them to the strong RFI from the Iridium satellites. These provide estimates for the desired signal in the presence of RFI, by exploiting distinguishing characteristics of the RFI, such as its polarization, statistics, and periodicity. Our data are dynamic spectra with full Stokes parameters and 1[Formula: see text]ms time resolution. Moreover, since most man-made RFI is strongly polarized, we use the data to compare its unpolarized component with its Stokes I. This approach on its own reduces the RFI intensity by many tens of dBs. A comprehensive approach that also recognizes non-Gaussian statistics, and the time and frequency structure inherent in the RFI, permits exceedingly effective post-detection excision provided full Stokes intensity data are available.
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Silvestre, Antonio M., Ana Carolina J. Pinto, Lidiane S. Miranda, Leandro Aparecido F. Silva, Daniel M. Casali, Katia Lirian R. Souza, Werner F. Schleifer, Jessica G. Cardin, Vanessa Gomes L. Gasparini, and Danilo D. Millen. "PSIX-3 Feedlot performance and rumen morphometrics of Nellore cattle differing in phenotypic residual feed intake." Journal of Animal Science 98, Supplement_4 (November 3, 2020): 421–22. http://dx.doi.org/10.1093/jas/skaa278.734.
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Abstract This study, conducted at São Paulo State University feedlot, Dracena campus, Brazil, had the objective to evaluate the effect of ranking Nellore bulls according to residual feed intake (RFI) on feedlot performance and rumen morphometric variables. Twenty-seven 18-mo-old Nellore bulls (425.5 ± 20.1 kg) were randomly allocated in 27 pens (one animal per pen) and fed for 107 days. The multiple step-up diets program consisted of ad libitum feeding of diets with the concentrate level increasing from 70% to 86% concentrate. At harvest, rumen epithelium samples were collected from cranial for rumen morphometric measurements. The RFI was calculated by the difference between the predicted DMI values [DMI = (0.0544*BW0.75) + (2.9659*ADG)] and observed DMI. Then, Nellore bulls were distributed into RFI groups: High (0.5 SD above the mean; n = 8), Medium (±0.5 SD of the mean; n=9) and Low (0.5 SD below the mean; n = 10). Low-RFI Nellore bulls improved (P = 0.04) G:F when compared to High- and Medium-RFI animals (0.142 vs. 0.125 and 0.130; respectively); however, no significant RFI grouping effect was observed for ADG (P = 0.54), final BW (P = 0.54), HCW (P = 0.27), dressing percentage (P = 0.24), final LM area (P = 0.87), final 12th rib fat (P = 0.82), final P8 fat thickness (P = 0.67) and final marbling (P = 0.82). Regarding rumen morphometrics, High-RFI Nellore bulls had larger (P = 0.09) rumen absorptive surface area than Low- and Medium-RFI animals (43.31 vs. 32.95 and 31.27; respectively), which was associated to the greater (P = 0.01) DMI presented by High-RFI animals (10.2 vs. 9.1 and 9.0 for Medium- and Low-RFI Nellore bulls; respectively). Nevertheless, no significant RFI grouping effect was observed for number of papillae (P = 0.28) or mean papillae area (P = 0.61). Thus, Low-RFI Nellore bulls improved feed efficiency without promoting any positive effects on carcass traits and rumen morphometrics.
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Chen, Y., P. F. Arthur, I. M. Barchia, K. Quinn, P. F. Parnell, and R. M. Herd. "Using gene expression information obtained by quantitative real-time PCR to evaluate Angus bulls divergently selected for feed efficiency." Animal Production Science 52, no. 11 (2012): 1058. http://dx.doi.org/10.1071/an12098.
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Residual feed intake (RFI) is a measure of feed efficiency in beef cattle. Young Angus bulls from lines of cattle divergently selected for RFI were used in a gene expression profiling study of the liver. Quantitative real-time PCR (qPCR) assay was used to quantify the differentially expressed genes and the information was used to examine the relationships between the genes and RFI and to classify the bulls into their respective RFI group. Gene expression of 21 genes in liver biopsies from 22 low RFI and 22 high RFI bulls were measured by qPCR. Gene expressions of 14 of the 21 genes were significantly correlated with RFI. The expression of the genes was used in a principal component analysis from which five components were extracted. The five principal components explained 70% of the variation in the dependency structure. The first component was highly correlated (correlation coefficient of 0.69) with RFI. The genes of the glutathione S-transferase Mu family (GSTM1, GSTM2, GSTM4), protocadherin 19 (PCDH19), ATP-binding cassette transporter C4 (ABCC4) and superoxide dismutase 3 (SOD3) are in the xenobiotic pathway and were the key factors in the first principal component. This highlights the important relationship between this pathway and variation in RFI. The second and third principal components were also correlated with RFI, with correlation coefficients of –0.28 and –0.20, respectively. Two of the four important genes of the second principal component work coordinately in the signalling pathways that inhibit the insulin-stimulated insulin receptor and regulate energy metabolism. This is consistent with the observation that a positive genetic correlation exists between RFI and fatness. The important genes in the third principal component are related to the extracellular matrix activity, with low RFI bulls showing high extracellular matrix activity.
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Richardson, E. C., R. M. Herd, V. H. Oddy, J. M. Thompson, J. A. Archer, and P. F. Arthur. "Body composition and implications for heat production of Angus steer progeny of parents selected for and against residual feed intake." Australian Journal of Experimental Agriculture 41, no. 7 (2001): 1065. http://dx.doi.org/10.1071/ea00095.
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Yearling Angus steer progeny of parents selected for low residual feed intake (RFI; high efficiency) or high RFI (low efficiency) were evaluated for feed intake, growth and differences in body composition. RFI is the difference between actual feed intake and expected feed intake based on an animal’s size and growth over a test period. Individual intakes of a high grain content ration and growth rates were recorded for 140 days and then the steers were slaughtered for measurement of body composition. All internal organs and non-carcass fat depots were removed, weighed and ground for chemical analysis. Carcasses were kept overnight in the chiller and the left half of every carcass physically dissected into retail cuts, and then into total fat, lean and bone. Carcass fat and lean were then combined and ground for chemical analysis. Steers from low RFI parents ate less (P<0.05) than the steers from high RFI parents, for similar rates of growth. Improvement in RFI was accompanied by small changes in body composition towards greater lean and less fat in the progeny of low RFI parents. Correlations of sire estimated breeding values for RFI with end of test whole body chemical protein, chemical fat and a principal component that condensed information on fat and lean body composition at the end of the test, were statistically significant. These confirmed there was a genetic association between body composition and RFI, with fatness being associated with higher RFI (i.e. lower efficiency). However, the correlations were small and suggested that less than 5% of the variation in sire RFI was explained by variation in body composition of their steer progeny. There was no evidence that a difference in the chemical composition of gain over the test explained the greater intake of metabolisable energy (ME) by the high RFI steers. The results suggest that the difference in ME intake following a single generation of divergent selection for RFI was due to metabolic processes rather than to changes in body composition.
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Uranga, Ekhi, Álvaro Llorente, Judit González, Antonio de la Fuente, Roger Oliva, Yan Soldo, and Flávio Jorge. "SMOS ESA RFI Monitoring and Information Tool: Lessons Learned." Remote Sensing 14, no. 21 (October 27, 2022): 5387. http://dx.doi.org/10.3390/rs14215387.
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The issue of Radio Frequency Interference (RFI) is a widespread problem in most microwave Earth observation missions, and passive instruments are particularly sensitive to RFI. This is the case for SMOS, Soil Moisture and Ocean Salinity, a satellite of the European Space Agency, which operates in the 1400–1427 MHz band, where all emissions are prohibited. Notwithstanding this regulatory framework, SMOS has been affected by RFI all around the world since the beginning of operations in 2010. In the first years of operations, manual detection processes and reporting of RFI to National Regulatory Authorities were in place in order to mitigate the detected sources. After 12 years, a tool called ERMIT (ESA RFI Monitoring and Information Tool) has been developed at ESAC (European Space Astronomy Center). This tool helps the SMOS RFI team in its spectrum monitoring tasks (e.g., RFI monitoring, logging, and reporting) thus allowing it to counteract RFI pollution more efficiently, providing external users with detailed and user-friendly information on the L-band RFI observed by SMOS. The ERMIT tool is now publicly available. This document aims at describing the needs that lead to the development of ERMIT and at presenting the information made available by it.
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Herd, R. M., P. F. Arthur, C. D. K. Bottema, A. R. Egarr, G. H. Geesink, D. S. Lines, S. Piper, J. P. Siddell, J. M. Thompson, and W. S. Pitchford. "Genetic divergence in residual feed intake affects growth, feed efficiency, carcass and meat quality characteristics of Angus steers in a large commercial feedlot." Animal Production Science 58, no. 1 (2018): 164. http://dx.doi.org/10.1071/an13065.
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Growth, feed intake, feed efficiency, and carcass and meat quality characteristics of 136 Angus steers differing in genetic merit for post-weaning residual feed intake (RFIp) were measured over 251 days in a large commercial feedlot. The steers were evaluated in two groups, low (Low-RFI) and high (High-RFI) genetic RFIp, measured by estimated breeding values for RFIp (RFIp-EBV). The difference in RFIp-EBV between the Low- and High-RFI groups was 1.05 kg/day (–0.44 vs 0.61 kg/day; P < 0.05). The Low- and High-RFI steers were similar (P > 0.05) in age (445 vs 444 days) and weight (435 vs 429 kg) at induction, and at the end of the feeding period (705 vs 691 kg). Average daily gain (ADG) over 251 days had a small negative association with variation in RFIp-EBV (P < 0.05), reflecting a 3.6% greater ADG accompanying a difference of 1 kg/day in RFIp-EBV. Pen feed intake and feed conversion by the Low-RFI group were 10.4 kg/day and 9.3 kg/kg, and for the High-RFI group were 11.1 kg/day and 10.4 kg/kg, but without availability of individual animal feed-intake data it was not possible to test for significant differences. Carcass weight and dressing-percentage was similar for the Low- and High-RFI steers. High-RFI steers had a significantly (P < 0.05) greater depth of subcutaneous rib fat at induction and finished with 5 mm more (P < 0.05) fat at the 10/11th ribs on the carcass than the Low-RFI steers. Cross-sectional area of the eye-muscle and three measures of intramuscular or marbling fat did not differ (P > 0.05) between the Low- and High-RFI steers. Shear force was higher (P < 0.05) in meat samples aged for 1 day from the Low-RFI steers, but there was no difference (P > 0.05) from the High-RFI steers after 7 days of ageing. Compression values for meat samples aged for 1 day did not differ between the RFI groups but were higher in meat samples aged for 7 days from the Low-RFI steers. For these Angus steers, genetic superiority in RFI was associated phenotypically with superior weight gain, decreased rib fat depth, slightly less tender meat, and no compromise in marbling fat or other carcass and meat quality traits.
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Johnson, Chinju, Carolyn Fitzsimmons, Igor Kovalchuk, John Kastelic, and Jacob Thundathil. "Testis-specific changes in gene expression of post-pubertal beef bulls divergent for residual feed intake and exposure to different pre-natal diets." Animal Production Science 60, no. 12 (2020): 1491. http://dx.doi.org/10.1071/an19524.
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Context Selection for residual feed intake (RFI) and its impact on male reproductive development has had mixed reviews in the past. Our previous studies demonstrated earlier puberty, larger testes and greater percentage of progressively motile sperm in high-RFI bulls. However, the molecular mechanisms within testes of bulls with varying RFI remain unclear. Aims To determine the effect of RFI and pre-natal diet on the expression patterns of testicular genes and use this information to explain differences observed across RFI. Methods The study included 25 purebred-Angus bulls with a genetic background of either high or low RFI and fed either normal or low pre-natal nutrition from 30 to 150 days post conception. After slaughter (17 months), testicular tissue was recovered, and RNA was extracted and sequenced. Key results Of 19218 expressed genes, 17 were differentially expressed for RFI (including PLCD1, INPP4B), with no differences being observed for pre-natal diet or diet × RFI interaction (false discovery rate) < 0.1%). KEGG pathway analysis indicated that differentially expressed genes were associated with inositol phosphate metabolism, and phosphatidylinositol signalling. On the basis of a candidate gene-expression study, IGF1R was upregulated in high-RFI bulls (P < 0.1). Conclusions Increased expression of IGF1R and lowered PLCD1 and INPP4B expression could activate PI3K–Akt signalling responsible for cell growth, proliferation and steroid metabolism in high-RFI bulls. Implications Selecting bulls for feed efficiency might affect molecular networks associated with reproduction and fertility.
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Jorge-Smeding, Ezequiel, Sergio Polakof, Muriel Bonnet, Stephanie Durand, Delphine Centeno, Mélanie Pétéra, Sébastien Taussat, and Gonzalo Cantalapiedra-Hijar. "Untargeted metabolomics confirms the association between plasma branched chain amino acids and residual feed intake in beef heifers." PLOS ONE 17, no. 11 (November 29, 2022): e0277458. http://dx.doi.org/10.1371/journal.pone.0277458.
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This study explored plasma biomarkers and metabolic pathways underlying feed efficiency measured as residual feed intake (RFI) in Charolais heifers. A total of 48 RFI extreme individuals (High-RFI, n = 24; Low-RFI, n = 24) were selected from a population of 142 heifers for classical plasma metabolite and hormone quantification and plasma metabolomic profiling through untargeted LC-MS. Most efficient heifers (Low-RFI) had greater (P = 0.03) plasma concentrations of IGF-1 and tended to have (P = 0.06) a lower back fat depth compared to least efficient heifers. However, no changes were noted (P ≥ 0.10) for plasma concentrations of glucose, insulin, non-esterified fatty acids, β-hydroxybutyrate and urea. The plasma metabolomic dataset comprised 3,457 ions with none significantly differing between RFI classes after false discovery rate correction (FDR > 0.10). Among the 101 ions having a raw P < 0.05 for the RFI effect, 13 were putatively annotated by using internal databases and 6 compounds were further confirmed with standards. Metabolic pathway analysis from these 6 confirmed compounds revealed that the branched chain amino acid metabolism was significantly (FDR < 0.05) impacted by the RFI classes. Our results confirmed for the first time in beef heifers previous findings obtained in male beef cattle and pointing to changes in branched-chain amino acids metabolism along with that of body composition as biological mechanisms related to RFI. Further studies are warranted to ascertain whether there is a cause-and-effect relationship between these mechanisms and RFI.
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Aibinu, Ajibade A., Simon Carter, Valerie Francis, and Paulo Vaz-Serra. "Request for information frequency and their turnaround time in construction projects." Built Environment Project and Asset Management 10, no. 1 (August 26, 2019): 1–15. http://dx.doi.org/10.1108/bepam-10-2018-0130.
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Purpose The purpose of this paper is to study the nature of request for information (RFIs) on construction projects by using data analytics to understand the frequency of RFIs, when they occur on projects, and the relationship between project characteristics and frequency of RFIs and between project characteristics and RFI turnaround time. Design/methodology/approach A data-analytic approach using RStudio and Minitab software on 168 construction project cases in Australia and New Zealand involving 1,032,949 correspondences and 53,042 RFI event records made available by Aconex, one of the world largest cloud-based project management platform. Findings Large and complex projects tend to have significantly larger number of RFI events per day and longer RFI turnaround when compared with smaller and less complex projects. Projects with fewer users per organisation recorded a higher RFI turnaround time when compared with projects with more users per organisation – users mean persons involved in managing the project using the online platform (an index of project complexity). RFIs occur early on less complex projects and occur later on more complex projects. Research limitations/implications Benchmarks of RFI incidences and turnaround time have been developed for various project characteristics and, practitioners can use them to monitor the RFI performance of projects. Organisations need to pay greater attention to staffing levels needed to handle RFIs to reduce RFI turnaround time. Originality/value A data-analytic study of RFI yielded insights for managing RFIs. The findings of previous studies on RFIs are difficult to generalise because they are based on single project case study. The influence of project characteristics on RFI frequency and RFI turnaround time is not yet known.
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Huntley, Clayton C., William J. Weiss, Anna Gazumyan, Aron Buklan, Boris Feld, William Hu, Thomas R. Jones, et al. "RFI-641, a Potent Respiratory Syncytial Virus Inhibitor." Antimicrobial Agents and Chemotherapy 46, no. 3 (March 2002): 841–47. http://dx.doi.org/10.1128/aac.46.3.841-847.2002.
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ABSTRACT Human respiratory syncytial virus (RSV), a paramyxovirus, is a major cause of acute upper and lower respiratory tract infections in infants, young children, and adults. RFI-641 is a novel anti-RSV agent with potent in vitro and in vivo activity. RFI-641 is active against both RSV type A and B strains. The viral specificity and the large therapeutic window of RFI-641 (>100-fold) indicate that the antiviral activity of the compound is not due to adverse effects on normal cells. The potent in vitro activity of RFI-641 can be translated to efficacy in vivo: RFI-641 is efficacious when administered prophylactically by the intranasal route in mice, cotton rats, and African green monkeys. RFI-641 is also efficacious when administered therapeutically (24 h postinfection) in the monkey model. Mechanism of action studies indicate that RFI-641 blocks viral F protein-mediated fusion and cell syncytium formation.
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Parsons, Cory T., Julia M. Dafoe, Samuel A. Wyffels, Timothy DelCurto, and Darrin L. Boss. "The Influence of Residual Feed Intake and Cow Age on Beef Cattle Performance, Supplement Intake, Resource Use, and Grazing Behavior on Winter Mixed-Grass Rangelands." Animals 11, no. 6 (May 23, 2021): 1518. http://dx.doi.org/10.3390/ani11061518.
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The objectives of this study were to evaluate the influence of RFI and cow age on the supplement intake and grazing behavior of beef cattle. Average daily supplement intake (kg/cow/d) displayed an RFI × cow age interaction (p < 0.01), with a linear increase in average daily supplement intake with increasing RFI of 3-year-old cows (p < 0.01). Average daily supplement intake (g ∙ kg BW−1 ∙ d−1) displayed an RFI × cow age interaction (p < 0.01), with a quadratic effect on supplement intake of 3-year-old cows (p = 0.01). Cow age displayed a quadratic effect on variation of supplement intake (p < 0.01), where 1-year-old cows had a greater CV of supplement intake than all other cow ages (p < 0.01). Distance traveled displayed a cow age × RFI interaction (p = 0.02), where high-RFI 5-year-old cows traveled further per day than low 5-year-old RFI cows. The probability of grazing site selection was influenced by cow age (p ≤ 0.03). In summary, heifer post-weaning RFI had minimal effects on beef cattle performance, grazing behavior, or resource utilization; however, cow age impacted both grazing behavior and resource use.
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Xu, Wei, Weida Xing, Chonghua Fang, Pingping Huang, Weixian Tan, and Zhiqi Gao. "RFI Suppression for SAR Systems Based on Removed Spectrum Iterative Adaptive Approach." Remote Sensing 12, no. 21 (October 27, 2020): 3520. http://dx.doi.org/10.3390/rs12213520.
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A synthetic aperture radar (SAR) system can be seriously contaminated by radio frequency systems because of working in the same microwave frequency bands, which would degrade the SAR image quality and affect the accuracy of image interpretation. In this paper, a novel radio frequency interference (RFI) suppression approach including RFI identification, band-stop filtering and a removed spectrum iterative adaptive approach (RSIAA) is proposed. First, the smoothing process is added before RFI signal detection to improve the RFI detection capacity. Afterwards, the band-stop filtering with a broaden factor is proposed to mitigate the residual RFI, and it ensures the accuracy of the following removed spectrum recovery by the RSIAA. Finally, the removed spectrum components are estimated from available adjacent spectrum data by the RSIAA in turn to obtain the desired range spectra. Compared with the conventional range frequency filtering method for RFI suppression, the capacity of the weak RFI signal detection is improved, and the increased sidelobes due to the discontinuous spectra are well suppressed. Simulation experiments on both simulated SAR raw data, Gaofen-3 and Sentinel-1 SAR raw data validate the proposed RFI suppression approach.
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Kerrigan, Joshua, Paul La Plante, Saul Kohn, Jonathan C. Pober, James Aguirre, Zara Abdurashidova, Paul Alexander, et al. "Optimizing sparse RFI prediction using deep learning." Monthly Notices of the Royal Astronomical Society 488, no. 2 (July 8, 2019): 2605–15. http://dx.doi.org/10.1093/mnras/stz1865.
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ABSTRACT Radio frequency interference (RFI) is an ever-present limiting factor among radio telescopes even in the most remote observing locations. When looking to retain the maximum amount of sensitivity and reduce contamination for Epoch of Reionization studies, the identification and removal of RFI is especially important. In addition to improved RFI identification, we must also take into account computational efficiency of the RFI-Identification algorithm as radio interferometer arrays such as the Hydrogen Epoch of Reionization Array (HERA) grow larger in number of receivers. To address this, we present a deep fully convolutional neural network (DFCN) that is comprehensive in its use of interferometric data, where both amplitude and phase information are used jointly for identifying RFI. We train the network using simulated HERA visibilities containing mock RFI, yielding a known ‘ground truth’ data set for evaluating the accuracy of various RFI algorithms. Evaluation of the DFCN model is performed on observations from the 67 dish build-out, HERA-67, and achieves a data throughput of 1.6 × 105 HERA time-ordered 1024 channelled visibilities per hour per GPU. We determine that relative to an amplitude only network including visibility phase adds important adjacent time–frequency context which increases discrimination between RFI and non-RFI. The inclusion of phase when predicting achieves a recall of 0.81, precision of 0.58, and F2 score of 0.75 as applied to our HERA-67 observations.
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Rocha, Raizza Fátima Abadia Tulux, Andréa Roberto Duarte Lopes Souza, Maria Da Graça Morais, Mayara Mitiko Yoshihara Carneiro, Henrique Jorge Fernandes, Gelson Luís Dias Feijó, Bruna Biava de Menezes, and Catherine Cecília Walker. "Performance, carcass traits, and non-carcass components of feedlot finished lambs from different residual feed intake classes." Semina: Ciências Agrárias 39, no. 6 (November 30, 2018): 2645. http://dx.doi.org/10.5433/1679-0359.2018v39n6p2645.
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This study aimed to assess the performance, carcass traits, and non-carcass components of feedlot finished Texel crossbred lambs from different residual feed intake classes (RFI). Forty-seven uncastrated male Texel crossbred lambs (¾ Texel + ¼ Pantaneira) tested here were 4-month-old with an initial weight of 29.9 ± 5.5 kg. The lambs were confined for 70 days for individual dry matter intake (DMI) and average daily gain (ADG) assessment. The diet containing corn silage was provided as roughage, while the concentrate consisted of corn grain, soybean meal, urea, and mineral mixture with a 40:60 roughage to concentrate ratio and 76.34% total digestible nutrients (TDN). After confinement for 70 days, the lambs were slaughtered to assess carcass traits and non-carcass components. Based on the RFI, lambs were divided into three classes according to the standard deviation (sd): Positive RFI (inefficient, 0.5 above the mean), Negative RFI (efficient, 0.5 below the mean), and Medium RFI (intermediate). Classes with Negative (efficient) and Positive RFI (inefficient) showed no differences in ADG (0.321 vs 0.306 kg; P > 0.05). Dry matter intake (g d-1), and percentage of body weight (BW) differed significantly between the RFI classes (P < 0.05). Compared to lambs in the inefficient class, those in the efficient class (Negative RFI) showed a 9% reduction in DMI and had the same ADG. The lambs in either Positive or Negative RFI classes showed no weight differences between non-carcass components (P > 0.05). The RFI classes showed no differences in shrunk body weight, hot carcass weight, hot dressing, and weight of commercial cuts (P > 0.05). They showed no differences in neck, shoulder + shank, loin, rack, flank steak, rack cap off, and leg weights (P > 0.05). Our results indicate that improvement in feed efficiency, as a function of the RFI index, does not compromise performance and carcass traits of Texel crossbred lambs.
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Paz, Ana Carolina Almeida Rollo de, Márcio Machado Ladeira, Priscilla Dutra Teixeira, Roberta Carrilho Canesin, Camila Delveaux Araujo Batalha, Maria Eugênia Zerlotti Mercadante, and Sarah Figueiredo Martins Bonilha. "Performance and muscle lipogenesis of calves born to Nellore cows with different residual feed intake classification." PLOS ONE 17, no. 7 (July 29, 2022): e0272236. http://dx.doi.org/10.1371/journal.pone.0272236.
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This study aimed to evaluate relationships among maternal residual feed intake (RFI) with growth performance and expression of genes involved in lipid metabolism in offspring of Nellore cattle. Fifty-three cows classified as negative or positive RFI by genomic prediction were exposed to fixed-time artificial insemination (FTAI) protocols at 2 and 3 years of age using semen from the same bull. In the first year, cows gestated under grazing conditions and nursed their calves in the feedlot. In the second year, the opposite occurred. Cows were weighed every 28 days during pregnancy and calves were weighed at birth and every 28 days until weaning. Ultrasound images were collected from the carcass of cows and calves. Muscle gene expression was evaluated in calves at birth and weaning. Data were analyzed by year considering the fixed effects of RFI class and FTAI protocol for variables measured in cows, and RFI class, FTAI protocol and sex for variables measured in calves. There was no effect of maternal RFI on calves performance in the first year. Lower expression of FABP4 gene and trend towards lower expression of SREBF1 and LPL genes were detected in samples collected after birth from calves born to negative RFI cows, indicating that adipogenesis was reduced during the fetal and neonatal period. In the second year, negative RFI cows had greater subcutaneous fat thickness than positive RFI cows, and their calves tended to be heavier at birth and to have less rump fat thickness at weaning. No significant differences in expression of genes studied were detected between cow RFI classes. Nellore cows classified as negative RFI consume less feed and produce calves whose growth potential is similar to that of calves produced by positive RFI cows.
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Johnson, Jocelyn R., Ira L. Parsons, Gordon E. Carstens, Luis Orlindo Tedeschi, Claas Heuer, and Nader Deeb. "181 Characterization of feeding-behavior patterns and application of chemometrics to predict residual feed intake based on feeding-behavior traits in growing Holstein heifers." Journal of Animal Science 97, Supplement_1 (July 2019): 61–62. http://dx.doi.org/10.1093/jas/skz053.138.
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Abstract Objectives of this study were to characterize feeding-behavior (FB) patterns in growing dairy heifers with divergent RFI phenotypes (±0.50 SD) and to evaluate the accuracy of partial least squares regression (PLSR) models to predict RFI based on FB traits. Performance, DMI, and FB traits were measured for 70 to 100 d in 15 trials with Holstein heifers (n = 611) fed a corn-silage based ration. Seventeen FB traits were evaluated: frequency and duration of bunk visit (BV) and meal events, head-down duration (HDD), meal length, maximum non-feeding interval, corresponding day-to-day variation (SD) of these traits, and ratios of HDD per BV duration and meal duration, HDD per meal duration, and BV events per meal event. Data were analyzed using a mixed model that included RFI group and trial. The PLSR model for RFI was developed using cross-validation procedures (Leave-One-Out) in JMP (SAS), with FB traits as independent variables. Low-RFI heifers consumed 24% less (P < 0.01) DMI and had lower (P < 0.01) day-to-day DMI variation than high-RFI heifers. Distinct differences were observed in FB patterns between low- and high-RFI heifers (Table 1). Eight of 17 FB traits were included [selected based on variable of importance (VIP) score > 0.80] in the PLSR model that explained 33% of the variation in RFI. Head-down duration had the highest VIP score; accordingly, low-RFI animals had 44% lower HDD and 30 and 40% lower ratios of HDD per BV duration and meal duration, respectively. Additionally, low-RFI animals had 20 and 18% fewer BV and meal events per day, spent 21% less time eating during BV events, and had reduced day-to-day variation in HDD and meal frequency. For this study, distinctive differences were observed in the FB patterns of Holstein heifers with divergent RFI, which explained 33% of the between-animal variation in RFI.
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Chen, Y., P. F. Arthur, R. M. Herd, K. Quinn, and I. M. Barchia. "Using genes differentially expressed in bulls to classify steers divergently selected for high and low residual feed intake." Animal Production Science 52, no. 7 (2012): 608. http://dx.doi.org/10.1071/an11266.
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Feed efficiency is an economically important trait in livestock and residual feed intake (RFI) is a commonly used measure of the trait in beef cattle. Residual feed intake is the difference between the actual feed intake recorded over a test period and the expected feed intake of an animal based on its size and growth rate. It is a heritable trait, and efficient animals have lower RFI values. Several genes have been identified as being differentially expressed in the liver of Angus bulls that have been divergently selected for RFI. The objective of this study was to use genes that are differentially expressed in bulls to classify Angus steers from the same divergent RFI selection lines. Liver samples were collected at slaughter from 40 high RFI and 40 low RFI steers that were ~23 months old, and had just completed a 251-day feedlot feeding period. RNA samples from the livers were assayed by quantitative real-time PCR for 14 genes, which have been identified previously in bulls. Steers were not measured for RFI, hence the estimated breeding values (EBV) for RFI of their parents were used to calculate their mid-parent (average of the two parents) RFI-EBV. Correlation and discriminant analyses were conducted on the normalised quantitative real-time PCR data from the steers. Discriminant analysis was also conducted on the bull data for comparison. In the steers, 8 out of the 14 genes were significantly (P < 0.05) correlated with RFI-EBV. Two genes from the glutathione S-transferase mu family (GSTM1 and GSTM2) and the S100 calcium-binding protein A10 (S100A10) had the highest correlations with RFI-EBV, with correlation coefficients of 0.59, 0.44 and 0.36, respectively. Based on the 14 expressed genes, 84% of the steers and 98% of the bulls were correctly classified into their respective RFI selection lines. The results of this study indicate that a high proportion of the genes that were differentially expressed in the original study with bulls were also differentially expressed in this study with steers. The high accuracy in classification obtained in this study shows that the transcriptional approach to the study of the biological processes involved in variation in RFI has great potential for identification of candidate genes.
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Basarab, J. A., M. G. Colazo, D. J. Ambrose, S. Novak, D. McCartney, and V. S. Baron. "Residual feed intake adjusted for backfat thickness and feeding frequency is independent of fertility in beef heifers." Canadian Journal of Animal Science 91, no. 4 (December 2011): 573–84. http://dx.doi.org/10.4141/cjas2011-010.
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Basarab, J. A., Colazo, M. G., Ambrose, D. J., Novak, S., McCartney, D. and Baron, V. S. 2011. Residual feed intake adjusted for backfat thickness and feeding frequency is independent of fertility in beef heifers. Can. J. Anim. Sci. 91: 573–584. This study examined the effects of residual feed intake (RFI), RFI adjusted for off-test backfat thickness (RFIfat) and RFI adjusted for off-test backfat thickness and feeding event frequency (RFIfat & activity) on heifer fertility and productivity. Beef heifers (n=190) were monitored for individual daily feed intake and feeding event activity over 108–112 d using the GrowSafe System® and assessed for age at puberty based on plasma progesterone concentration. Individual animal daily feed intake, feeding event activity and off-test backfat thickness were then used to calculate RFI, RFIfat and RFIfat & activity and group heifers as either negative ([−], RFI<0.0) or positive ([+], RFI≥0.0) for RFI. Heifers averaged 298 kg (SD=34) in body weight, were 276 days of age (SD=19) at the start of test, grew at 0.90 kg d−1 (SD=0.21), consumed 7.62 kg DM head−1 d−1 (SD=0.84) and had a feed conversion ratio of 8.93 (SD=2.43). Age (351 d, SD=43) and weight (367.3 kg, SD=45.0) at puberty were similar between [−] and [+] RFI heifers, but age at puberty was delayed in [−] RFIfat (P=0.04) and RFIfat & activity (P=0.08) heifers compared with [+] RFIfat and RFIfat & activity heifers. Efficient or [−] RFI heifer exhibited a lower pregnancy (76.84 vs. 86.32%, P=0.09) and calving rate (72.63 vs. 84.21%, P=0.05) compared with [+] RFI heifers. These differences were partially removed in [−] RFIfat and completely removed in [−] RFIfat & activity compared with their [+] RFI counterparts (pregnancy rate, 80.85 vs. 82.29%, P=0.80; calving rate, 75.53 vs. 81.25%, P=0.34). No differences were observed between efficient and inefficient heifers in calving difficulty, average calving date, age at first calving, calf birth weight, calf pre-weaning ADG, calf weaning weight and heifer productivity. However, [+] RFI heifers exhibited a 1.9-fold higher calf death loss compared with [−] RFI heifers (11.11% vs. 5.71%, P=0.24). This difference was more pronounced in [+] RFIfat and [+] RFIfat & activity heifers, which exhibited 2.2-fold (11.84% vs. 5.33%, P=0.15) and 3.0-fold (12.66% vs. 4.17%, P=0.06) higher calf death loss compared with [−] RFI heifers. There was no relationship of RFI adjusted for backfat thickness and feeding activity on fertility traits indicating that backfat thickness and feeding activity may be associated with feed intake and should be considered when selecting heifers for improved feed efficiency.
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Teaford, Max, Jason Gilliland, Olivia Hodkey, Tara McVeigh, Caleb Perry, Lyric Rains-Bury, and L. James Smart. "Preliminary Evaluation of the Moving Rubber Foot Illusion in a Sample of Female University Students." Perception 50, no. 11 (November 2021): 966–75. http://dx.doi.org/10.1177/03010066211058802.
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The Rubber Foot Illusion (RFI) is an illusion in which one is made to feel that a model foot is their own through synchronous visuo-tactile stimulation. Previous research suggests that the conditions the RFI can be elicited under are similar to those of the Rubber Hand Illusion (RHI). However, it was unknown if the RFI could be elicited by synchronous movement of a participant’s foot and a model foot. To examine this, we developed the Moving Rubber Foot Illusion (mRFI) and compared participants’ experience of it to the RFI. The results of this study suggests that the RFI can be elicited through synchronous movement, and results in more proprioceptive drift than a static variant of the RFI. More work is needed to better understand the mechanisms underlying the mRFI.
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LI, HUI, MENGGUO JING, and EILEEN CHIN MEI WONG. "Predicting the development of interrogative forms and functions in early years: a corpus-based study of Mandarin-speaking young children." Journal of Child Language 44, no. 1 (February 29, 2016): 216–38. http://dx.doi.org/10.1017/s0305000916000088.
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AbstractThis study examined the development of and possible predictors of interrogative forms and functions in early childhood Mandarin. All the interrogatives drawn from the Early Child Mandarin Corpus (168 children 2;6, 3;6, 4;6, and 5;6) were analyzed. The main results indicated that (i) there were significant age effects in interrogative forms and functions, with the periods between the ages of 3;6 and 4;6 and between the ages of 2;6 and 3;6 being critical in the early acquisition of interrogative forms and functions, respectively; (ii) the form–function preference was verified, with wh-questions being primarily used to seek information (RfI), and intonation/echo and rhetorical questions being used to request action (RfA); (iii) more than half (59·5%) of the Mandarin interrogatives were used for RfI, whereas only 38·9% of them were used for RfA; and (iv) age, TV viewing time, and parent–child conversation time were the significant predictors of interrogative development.
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Lancaster, Phillip A., Mike Davis, Jack Rutledge, and Larry Cundiff. "72 Relationships Among Lifetime Feed Efficiency Traits in Growing Heifers, Mature Cows and Their Progeny." Journal of Animal Science 99, Supplement_1 (May 1, 2021): 118–19. http://dx.doi.org/10.1093/jas/skab054.196.
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Abstract Uncertainty exists in relationships among feed efficiency traits in different production stages. The objective of this study was to evaluate the relationships among feed efficiency traits measured in various stages of production. Data were collected from 1953 through 1980 from dams (n = 160), and their progeny (n = 406). Individual feed intake was measured from 240 d of age through weaning of 3rd calf for dams, and from weaning to slaughter for progeny. Body weight was measured at 28-d intervals until first parturition for heifers and slaughter for progeny, and cows were weighed at parturition and weaning each production cycle. Milk yield of dams was measured at 14-d intervals throughout lactation. Residual feed intake was computed as the residual from linear regression of daily DMI on metabolic mid-test body weight, average daily gain, and milk yield for dams only with year-diet-breed factor as a random effect using lmer function in R software. Pearson correlation coefficients were computed using corr.test function. Pearson correlations of RFI with DMI ranged from 0.58 to 0.74 and with feed:gain or feed:milk ranged from 0.24 to 0.67 within production stage. Heifer RFI was correlated with cow RFI during parity 1 (0.74), but not parity 2 (0.11) or 3 (-0.06). Heifer RFI was correlated with progeny 3 RFI (0.17), but not progeny 1 or 2 RFI. Cow RFI was weakly correlated among parities (0.25 to 0.36) whereas feed:milk was strongly correlated (0.56 to 0.70). Cow RFI was not correlated with progeny RFI of the same parity. In conclusion, RFI was poorly correlated across stage of production.
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Aksoy, Mustafa, Hamid Rajabi, Pranjal Atrey, and Imara Mohamed Nazar. "Characteristics of the Global Radio Frequency Interference in the Protected Portion of L-Band." Remote Sensing 13, no. 2 (January 13, 2021): 253. http://dx.doi.org/10.3390/rs13020253.
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The National Aeronautics and Space Administration’s (NASA’s) Soil Moisture Active–Passive (SMAP) radiometer has been providing geolocated power moments measured within a 24 MHz band in the protected portion of L-band, i.e., 1400–1424 MHz, with 1.2 ms and 1.5 MHz time and frequency resolutions, as its Level 1A data. This paper presents important spectral and temporal properties of the radio frequency interference (RFI) in the protected portion of L-band using SMAP Level 1A data. Maximum and average bandwidth and duration of RFI signals, average RFI-free spectrum availability, and variations in such properties between ascending and descending satellite orbits have been reported across the world. The average bandwidth and duration of individual RFI sources have been found to be usually less than 4.5 MHz and 4.8 ms; and the average RFI-free spectrum is larger than 20 MHz in most regions with exceptions over the Middle East and Central and Eastern Asia. It has also been shown that, the bandwidth and duration of RFI signals can vary as much as 10 MHz and 10 ms, respectively, between ascending and descending orbits over certain locations. Furthermore, to identify frequencies susceptible to RFI contamination in the protected portion of L-band, observed RFI signals have been assigned to individual 1.5 MHz SMAP channels according to their frequencies. It has been demonstrated that, contrary to common perception, the center of the protected portion can be as RFI contaminated as its edges. Finally, there have been no significant correlations noted among different RFI properties such as amplitude, bandwidth, and duration within the 1400–1424 MHz band.
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Kelly, Alan K., Sinead M. Waters, Mark McGee, Rita G. Fonseca, Ciara Carberry, and David A. Kenny. "mRNA expression of genes regulating oxidative phosphorylation in the muscle of beef cattle divergently ranked on residual feed intake." Physiological Genomics 43, no. 1 (January 2011): 12–23. http://dx.doi.org/10.1152/physiolgenomics.00213.2009.
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Our objective was to evaluate the effects of phenotypic ranking on residual feed intake (RFI) on the transcription of genes 1) involved in the respiratory chain complex and 2) coding for transcriptional factors regulating mitochondrial biogenesis, across two contrasting diet types. Beef heifers ( n = 86) fed a diet comprising 70:30 concentrate-corn silage [low forage (LF)] over a 82-day period were ranked on RFI. The 10 highest (feed inefficient, high-RFI) and 10 lowest (feed efficient, low-RFI) ranking animals were selected for the current study. Biopsies of the M. longissimus dorsi were harvested following initial selection (LF diet) and again following a 6 wk period while the animals were offered a high-forage (HF) grass silage-only diet. Real-time PCR was used to quantify mRNA transcripts of 17 genes associated with cellular energetic efficiency. The mRNA expression of UCP3 tended to be upregulated (2.2-fold, P = 0.06) for the high-RFI compared with the low-RFI animals. mRNA transcripts coding for the transcription factor PGC-1α was 1.7-fold higher ( P = 0.01) in low compared with high-RFI animals. A phenotype × diet interaction was evident for the abundance of ANT1 mRNA transcript, with greater ( P = 0.04) expression levels detected in the low-RFI phenotype during the HF period, but no difference ( P = 0.50) between phenotypes during the LF period. A phenotype × diet interaction was also evident for COX II with greater expression levels detected ( P = 0.04) in the low compared with the high RFI phenotype while on LF but not the HF diet ( P = 0.22). These data suggest an association between cellular energetic efficiency and RFI in cattle.