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11.
Ana Clara B Menezes Kacie L McCarthy Cierrah J Kassetas Friederike Baumgaertner James D Kirsch Sheri Dorsam Tammi L Neville Alison K Ward Pawel P Borowicz Lawrence P Reynolds Kevin K Sedivec J Chris Forcherio Ronald Scott Joel S Caton Carl R Dahlen 《Journal of animal science》2021,99(2)
The objective of this study was to evaluate the effects of feeding vitamin and mineral (VTM) supplement and (or) rate of gain (GAIN) during early gestation on amino acid (AA) concentrations in allantoic fluid (ALF) and amniotic fluid (AMF) and maternal serum. Seventy-two crossbred Angus heifers (initial BW = 359.5 ± 7.1 kg) were randomly assigned to one of four treatments in a 2 × 2 factorial arrangement with main effects of VTM supplement (VTM or NoVTM) and rate of gain (GAIN; low gain [LG], 0.28 kg/d, vs. moderate gain [MG], 0.79 kg/d). The VTM treatment (113 g•heifer−1•d−1, provided macro and trace minerals and vitamins A, D, and E to meet 110% of the requirements specified by the NASEM in Nutrient requirements of beef cattle. Washington, DC: The National Academies Press. doi:10.17226/19014, 2016) was initiated 71 to 148 d before artificial insemination (AI). To complete the factorial arrangement of treatments, at breeding heifers were either maintained on the basal diet (LG), or received MG diet which was implemented by adding a protein/energy supplement to the LG diet. Thirty-five gestating heifers with female fetuses were ovariohysterectomized on d 83 of gestation and maternal serum, ALF, and AMF were collected. Samples were analyzed for concentrations of neutral AA: Ala, Asn, Cys, Gln, Gly, Ile, Leu, Met, Phe, Pro, Ser, Thr, Trp, Tyr, and Val; cationic AA: Arg, His, and Lys; and anionic AA: Asp and Glu. In serum, a VTM × GAIN interaction (P = 0.02) was observed for Glu, with greater concentrations for VTM-LG than VTM-MG. Concentrations of serum Cys, Met, and Trp were greater (P ≤ 0.03) for MG than LG. In ALF, concentrations of Glu were affected by a VTM × GAIN interaction, where VTM-MG was greater (P < 0.01) than all other treatments. Further, ALF from VTM had increased (P ≤ 0.05) concentrations of His, Asp, and 12 of the 14 neutral AA; whereas GAIN affected concentrations of Arg, Cys, and Asp, with greater concentrations (P ≤ 0.05) in MG heifers. In AMF, AA concentrations were not affected (P ≥ 0.10) by VTM, GAIN, or their interaction. In conclusion, increased concentrations of AA in maternal serum and ALF of beef heifers were observed at d 83 of gestation in response to VTM supplementation and rate of gain of 0.79 kg/d, which raises important questions regarding the mechanisms responsible for AA uptake and balance between the maternal circulation and fetal fluid compartments. 相似文献
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Kelsey T. Young Kevin K. Lahmers Holly S. Sellers David E. Stallknecht Rebecca L. Poulson Jerry T. Saliki Stephen Mark Tompkins Ian Padykula Chris Siepker Elizabeth W. Howerth Michelle Todd James B. Stanton 《Journal of veterinary diagnostic investigation》2021,33(2):202
RNA viruses rapidly mutate, which can result in increased virulence, increased escape from vaccine protection, and false-negative detection results. Targeted detection methods have a limited ability to detect unknown viruses and often provide insufficient data to detect coinfections or identify antigenic variants. Random, deep sequencing is a method that can more fully detect and characterize RNA viruses and is often coupled with molecular techniques or culture methods for viral enrichment. We tested viral culture coupled with third-generation sequencing for the ability to detect and characterize RNA viruses. Cultures of bovine viral diarrhea virus, canine distemper virus (CDV), epizootic hemorrhagic disease virus, infectious bronchitis virus, 2 influenza A viruses, and porcine respiratory and reproductive syndrome virus were sequenced on the MinION platform using a random, reverse primer in a strand-switching reaction, coupled with PCR-based barcoding. Reads were taxonomically classified and used for reference-based sequence building using a stock personal computer. This method accurately detected and identified complete coding sequence genomes with a minimum of 20× coverage depth for all 7 viruses, including a sample containing 2 viruses. Each lineage-typing region had at least 26× coverage depth for all viruses. Furthermore, analyzing the CDV sample through a pipeline devoid of CDV reference sequences modeled the ability of this protocol to detect unknown viruses. Our results show the ability of this technique to detect and characterize dsRNA, negative- and positive-sense ssRNA, and nonsegmented and segmented RNA viruses. 相似文献
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Obied HK Bedgood D Mailer R Prenzler PD Robards K 《Journal of agricultural and food chemistry》2008,56(19):8851-8858
Olive mill waste (OMW) contains substantial amounts of valuable antioxidant biophenols that can be recovered for possible applications in food, pharmaceutical, and cosmetic industries. However, the impact of cultivar, harvesting time, and seasonal variation on the phenolic composition of OMW has not yet been assessed. Total phenols, antioxidant activity, and phenol profiles of OMW extracts from five different Australian-grown cultivars (Barnea, Correggiola, Manzanillo, Mission, and Paragon) were studied at four different harvesting times in the 2004 season. The impact of seasonal variation was assessed by comparing total phenol content, antioxidant activity, and phenol profile of two cultivars (Correggiola and Mission) harvested in the 2004 and 2005 seasons. The phenol content and antioxidant activity at different harvesting times were mainly a function of the olive cultivar. Harvesting time had a quantitative effect rather than a qualitative effect on the phenol profile. Intercultivar and harvesting time variation accounted for a 2-5-fold change in the total phenol and antioxidant capacity, while levels of individual biophenols experienced up to 50-fold change. The phenol content and antioxidant capacity of OMW significantly changed between seasons with different variation patterns for different cultivars. 相似文献
17.
Xiaopeng Gao Sally Parsonage Mario Tenuta Kevin Baron Krista Hanis-Gervais Alison Nelson Dale Tomasiewicz Ramona Mohr 《American Journal of Potato Research》2017,94(4):390-402
Nitrogen fertilizer practices affect nitrous oxide (N2O) emissions from agricultural soils. The “4R” nutrient stewardship framework of using N fertilizer at the right rate, right source, right placement and right time can reduce N2O emissions while maintaining or improving yield of field crops, but understanding of how the various factors affect N2O emissions from irrigated processing potato is lacking. We examined the effects of selected 4R practices on emissions, using results from two irrigated processing potato studies each conducted in 2011 and 2012 in Manitoba, Canada. Experiment 1 examined combinations of source (urea, ESN), placement (pre-plant incorporation [PPI], banding), and rate (100 and 200 kg N ha-1) on a clay loam soil. Experiment 2 examined timing and source treatment combinations (urea PPI, ESN PPI, urea split, urea split/fertigation) on a loamy fine sandy soil. For Experiment 1, use of ESN at 200 kg ha-1 did not reduce area-, yield- and applied fertilizer N- based N2O emissions compared to urea at 200 kg ha-1, irrespective of placement. Emissions from pre-plant banding ESN at 200 kg ha?1, however, were 32% lower than from PPI ESN. For Experiment 2, compared to single pre-plant urea application, fertigation simulated by in-season application of urea ammonium nitrate (UAN) gave lower area-, yield- and applied fertilizer N- based emissions. Split urea ( \( \raisebox{1ex}{$2$}\!\left/ \!\raisebox{-1ex}{$3$}\right. \) pre-plant, \( \raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$3$}\right. \) hilling) also reduced area- and yield- based N2O emissions compared to single pre-plant urea application. Emissions were generally lower at the site with loamy fine sandy soil than the site with clay loam soil. These results demonstrate that combinations of “4R” practices rather than source alone are best to achieve reductions in N2O emissions from irrigated potato production. 相似文献
18.
Randomized complete block (RCB) design is the most widely used experimental design in biological sciences. As number of treatments increases, the block size become larger and it looses the capacity to control the variance within block, which is its original purpose. A method known as post hoc blocking could be used in these cases to improve the genetic parameter estimation and thus obtain an unbiased assessment of the performance of a given treatment. In trufgrass breeding, as other breeding program, this is a common challenge. The goal of this study was to test the capacity of different post hoc blocking designs to improve the genetic parameter estimation of zoysiagrass (Zoysia spp.). We evaluated two post hoc blocking designs; row–column (R–C) and incomplete block (IB) designs on five genotype trials located in Florida. The results showed that post hoc R–C design had superior model fitting than both the original RCB and the post hoc IB designs when studied at the single measurement level and at the site level. The narrow-sense heritability (0.24–0.40) and the genotype-by-measurement correlation (0.57–0.99) did not change significantly when R–C was compared to the original RCB design. The ranking of the top performing genotypes changed considerably when comparing RCB to R–C design, but the degree depended on the location analyzed. We conclude that the change in the ranking of the top (potentially select individuals) is coming from the better control of intra-block environmental variation, and this could potentially have a significant impact on the breeding selection process. 相似文献
19.
Ammar Elakhdar Toshihiro Kumamaru Kevin P. Smith Robert S. Brueggeman Ludovic J.A. Capo-chichi Shyam Solanki 《Journal of Crop Science and Biotechnology》2017,20(3):193-204
Changes in the relative genetic performance of genotypes across environments are referred to as genotype × environment interactions (GEIs). GEIs can affect barley breeding improvement for salt tolerance because it often complicates the evaluation and selection of superior genotypes. The present study evaluated the GEIs over 60 barley genotypes for yield components and grain yield in six salinity environments in North Delta, Egypt. Data were analyzed using the additive main effects and multiplicative interaction (AMMI) and Tai’s stability parameters. GEIs effects on yield explained 20.3, 20.1, 14.6, and 33.0% of the total variation besides, the first two principal components account for 67.3, 56.3, 64.3, and 83.7% of the explained variance in the four sets, respectively. Six genotypes namely G-4, G-7, G-20, G-34, G-36, and G-39 were found to be most stable and high yielding across environments (GY >2.00 t ha-1), and located close to zero projection onto the AEC ordinate. Tai’s stability parameters demonstrated that these genotypes were more responsive to the environmental changes. The genotypes G-50 and G-53 showed perfect/static stability (α = -0.95, -0.91, respectively). In contrast, the genotype; G-36 had α = 0 and λ = 1.10, indicating parallel with the environmental effects followed by G-44. Overall, we found that GEIs for grain yield are highly significant in all sets, suggesting that responded differently across environments. This interaction may be a result of changes in genotypes’ relative performance across environments, due to their differential responses to various abiotic factors. 相似文献
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Kevin A. Hughes Kerstin Scherer Petra Rettberg Pete Convey 《Soil biology & biochemistry》2006,38(6):1488-1490
In the Arctic, seasonal ozone depletion is resulting in periods of enhanced UV-B radiation at ground level while regional climate change is associated with increasing temperatures. These changes are likely to alter plant distribution, biodiversity and morphology, which may have knock-on effects for microbially driven biogeochemical cycling and other soil processes. Our study examined the transmission of solar UV radiation through arctic tundra plants using a portable UV radiometer and the DLR-biofilm biological UV dosimeter. A strong negative correlation was found between vegetation cover and UV transmission to the soil surface. Penetration of UV to the soil beneath tundra plants varied depending upon plant morphology, being greater through low creeping plants than cushion plants, grasses or mosses. UV transmission to the soil surface beyond the foliage edge also varied with plant morphology and the presence of flowers. 相似文献