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611.
M.R. ONeil G.P. Lardy M.E. Wilson C.O. Lemley L.P. Reynolds J.S. Caton K.A. Vonnahme 《Domestic animal endocrinology》2009,37(3):148-158
To evaluate the estrogenic potential of secoisolariciresinol diglycoside (SDG) found in linseed meal (LSM) on visceral organ mass, IGF-I, and thyroid hormone (T3 and T4) concentrations, 48 multiparous, ovariectomized ewes (54.6 ± 1.1 kg) were used in a 3 × 4 factorial arrangement. Main effects were length of LSM feeding (0, 1, 7, or 14 d) and length of exposure to estradiol-17β (E2) implant (0, 6, or 24 h prior to tissue collection). Implanting ewes with E2 for 24 h increased liver mass relative to empty body weight (EBW; g/kg EBW) compared with ewes implanted for 0 or 6 h (P ≤ 0.03), whereas feeding LSM for 14 d decreased liver mass compared with ewes fed LSM for 1 or 7 d (P ≤ 0.02). There was an LSM × E2 interaction (P = 0.01) for duodenal mass (g/kg EBW), LSM, and E2 tended (P = 0.07) to influence the stomach complex mass; however, ileal mass was not affected. Neither LSM nor E2 affected (P ≥ 0.12) CYP2C or CYP3A mRNA expression or cellularity of the liver. Exogenous E2 influenced circulating concentrations of IGF-I, T3, and T4. The estrogenic or anti-estrogenic potential of LSM is dependent upon the tissue, exposure to E2, and the duration of LSM feeding. Feeding LSM during gestation, lactation, or during the grow-finish phase warrants further investigation. 相似文献
612.
613.
M.K. Schmidt C.A. Reynolds A.H. Estrada R. Prošek H.W. Maisenbacher M.M. Sleeper M.A. Oyama 《Journal of Veterinary Cardiology》2009
ObjectivesTo evaluate amino-terminal pro-B type natriuretic peptide (NT-proBNP) concentration in dogs with renal dysfunction and normal cardiac structure and function.AnimalsEight dogs with renal disease, 23 healthy control dogs.MethodsSerum NT-proBNP concentration was measured in healthy dogs and dogs with renal disease using an ELISA validated for use in dogs. Affected dogs were eligible for inclusion if renal dysfunction was diagnosed based on urinalysis and serum chemistry, and if they were free of cardiovascular disease based on physical exam, systolic blood pressure, and echocardiography.ResultsThe geometric mean serum NT-proBNP concentration was significantly higher in dogs with renal disease (617 pmol/L; 95% CI, 260–1467 pmol/L) than in healthy control dogs (261 pmol/L; 95% CI, 225–303 pmol/L; P = 0.0014). There was a modest positive correlation between NT-proBNP and BUN and creatinine. Median NT-proBNP concentration was not significantly different between groups when indexed to BUN (median NT-proBNP:BUN ratio; renal, 14.2, IQR, 3.93–17.7 vs. control, 16.3, IQR, 9.94–21.2; P = 0.29) or creatinine (median NT-proBNP:creatinine ratio; renal, 204, IQR, 72.6–448 vs. control, 227, IQR, 179–308; P = 0.67).ConclusionDogs with renal disease had significantly higher mean serum concentration of NT-proBNP than control dogs. Renal function should be considered when interpreting NT-proBNP results as concentrations may be falsely elevated in dogs with renal dysfunction and normal cardiac function. The effect of renal disease was lessened by indexing NT-proBNP to BUN or creatinine. Future studies in dogs with both renal and heart disease are warranted. 相似文献
614.
Simple phosphorus saturation index to estimate risk of dissolved P in runoff from arable soils 总被引:1,自引:0,他引:1
Abstract. There is increasing evidence that phosphorus has been accumulating in the surface horizons of agricultural soils to the extent that some soils represent a potential diffuse source of pollution to surface waters. The relationships between equilibrium phosphorus concentration at zero sorption (EPC 0 ) of soil and a number of soil physicochemical variables were investigated in the surface layers of arable and grassland agricultural soils sampled from the Thame catchment, England. Soil EPC0 could be predicted from an equation including soil test (Olsen) P, soil phosphate sorption index (PSI) and organic matter content (OM) (R2 =0.88; P <0.001) across a range of soil types and land use. The simple index Olsen P/PSI was found to be a good predictor of EPC0 (R2 =0.77; P <0.001) and readily desorbable (0.02 m KCl extractable) P (R2 =0.73; P <0.001) across a range of soil types under arable having soil organic matter contents of <10%. 相似文献
615.
616.
Evaluating physiological traits to complement empirical selection for wheat in warm environments 总被引:4,自引:1,他引:3
M.P. Reynolds R.P. Singh A. Ibrahim O.A.A. Ageeb A. Larqué-Saavedra J.S. Quick 《Euphytica》1998,100(1-3):85-94
The response of spring wheat to heat stress has been determined in several hot wheat growing environments worldwide on different
types of germplasm. Physiological data has been collected to identify potential traits to assist in the empirical breeding
for heat tolerance. Initial studies focused on 10 established varieties to determine genetic diversity for heat tolerance,
identify association between heat tolerance and traits measured, and evaluate genotype by environment interaction (G x E).
Yields from over 40 hot environments were analysed for G x E, and relative humidity (RH) was identified as the major factor
determining relative genotype ranking. Further analysis focused on 16 environments: those with low RH and relatively high
yields, i.e., over 2.5 t ha-1. For these environments, mean yield of lines correlated with a number of physiological traits measured in Mexico, including
canopy temperature depression (CTD), membrane thermostability, leaf conductance and photosynthetic rate at heading, chlorophyll
content during grainfilling, leaf internal CO2 concentration, and dark respiration. Morphological traits were measured in all environments and the following showed associations
with yield: above ground biomass at maturity, days from emergence to anthesis and to maturity, grain number m-2, and ground cover estimated visually after heading. Subsequent studies focused on breeding material, namely recombinant inbred
lines derived from crosses between parents of contrasting heat tolerance, and 60 advanced breeding lines selected for performance
under heat stress. The genetic basis for association between heat tolerance and CTD was established by demonstrating a correlation
between the two traits in RILs (recombinant inbred lines). Data from RILs, as well as from the 60 advanced lines grown at
several international locations, indicated CTD to be a powerful and robust selection criterion for heat tolerance.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
617.
Kristen J. Reynolds Ron Johnson Robert M. Friendship Jennifer Brown Saad Enouri Ronette Gehring Terri L. OSullivan 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(11):1211
In Canada, piglets receive analgesia to control pain after surgical castration. There is interest in examining the potential to mix non-steroidal anti-inflammatory drugs with iron dextran prior to injection to minimize piglet handling and labor. The objective of this study was to compare pharmacokinetics and the relative bioavailability of ketoprofen given alone (3.0 mg/kg IM) versus the same dose of ketoprofen mixed with iron dextran (52.8 mg/kg IM) (ketoprofen + iron dextran) before injection in piglets. Piglets 8 to 11 d old were allocated into 2 treatment groups (n = 8/group). Plasma drug concentrations were measured using mass spectrometry at 13 time points after injection. No significant differences were detected between the 2 groups when examining pharmacokinetic parameters (e.g., Cmax, Tmax, AUC) or relative bioavailability for either S- or R-ketoprofen enantiomers (P > 0.05). However, pain control efficacy and food safety studies of these formulations are required to further examine this practice. 相似文献
618.
Selectivity matters: Rules of thumb for management of plate‐sized,sex‐changing fish in the live reef food fish trade 下载免费PDF全文
Holly K Kindsvater John D Reynolds Yvonne Sadovy de Mitcheson Marc Mangel 《Fish and Fisheries》2017,18(5):821-836
Effective management of fisheries depends on the selectivity of different fishing methods, control of fishing effort and the life history and mating system of the target species. For sex‐changing species, it is unclear how the truncation of age‐structure or selection of specific size or age classes (by fishing for specific markets) affects population dynamics. We specifically address the consequences of plate‐sized selectivity, whereby submature, “plate‐sized” fish are preferred in the live reef food fish trade. We use an age‐structured model to investigate the decline and recovery of populations fished with three different selectivity scenarios (asymptotic, dome‐shaped and plate‐sized) applied to two sexual systems (female‐first hermaphroditism and gonochorism). We parameterized our model with life‐history data from Brown‐marbled grouper (Epinephelus fuscoguttatus) and Napoleon fish (Cheilinus undulatus). “Plate‐sized” selectivity had the greatest negative effect on population trajectories, assuming accumulated fishing effort across ages was equal, while the relative effect of fishing on biomass was greatest with low natural mortality. Fishing such sex‐changing species before maturation decreased egg production (and the spawning potential ratio) in two ways: average individual size decreased and, assuming plasticity, females became males at a smaller size. Somatic growth rate affected biomass if selectivity was based on size at age because in slow growers, a smaller proportion of total biomass was vulnerable to fishing. We recommend fisheries avoid taking individuals near their maturation age, regardless of mating system, unless catch is tightly controlled. We also discuss the implications of fishing post‐settlement individuals on population dynamics and offer practical management recommendations. 相似文献