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101.
Rutherfurd SM Rutherfurd-Markwick KJ Moughan PJ 《Journal of agricultural and food chemistry》2007,55(9):3517-3522
A recently developed assay for determining available lysine (true ileal digestible reactive lysine) in foods and feedstuffs was applied to 20 commercially available cat foods. Semisynthetic diets, containing cat food as the sole protein source, were prepared. Titanium dioxide was included as an indigestible marker. The diets were fed to growing rats and digesta from the terminal ileum collected and analyzed, along with the diets, for reactive lysine. True reactive lysine digestibility was determined after correction for endogenous lysine loss at the terminal ileum of rats fed an enzyme-hydrolyzed casein-based diet. The amounts of digestible total lysine (conventional method) were also determined. Ileal total lysine digestibility significantly (P<0.05) underestimated (3.6-10.2%) lysine availability (ileal reactive lysine digestibility) for most of the cat foods tested. Ileal digestible total lysine significantly (P<0.05) overestimated the amount of dietary available lysine for all of the cat foods tested by between 38 and 143%. Total lysine digestibility determined using the conventional method of lysine analysis was inaccurate when applied to commercially available cat foods. 相似文献
102.
Two new naturally occurring formylated phloroglucinol compounds (FPCs), a dimer, loxophlebal B (10) and a cyclized FPC, loxophlebene (8) together with eight other formylated phloroglucinols (1–7 and 9) were isolated from the chloroform-methanol (8:2) extract of the leaves of Eucalyptus loxophleba ssp. lissophloia. The structures of new compounds were established by comprehensive spectral analysis and by comparison of their NMR data with those of related compounds in the literature. All the isolated compounds were evaluated for anti-leishmanial activity against promastigotes of Leishmania donovani. 相似文献
103.
A biophysical model to assess the trade‐off between larval recruitment and catch in southern Australia's largest prawn fishery 下载免费PDF全文
Lachlan Mcleay Mark Doubell Shane Roberts Cameron Dixon Lorenzo Andreacchio Charles James John Luick John Middleton 《Fisheries Oceanography》2016,25(2):164-182
Data from stock assessment surveys, published research and climate sensors were linked to model the interaction between fishing, physical‐oceanographic processes and spatial patterns of larval settlement for western king prawn [Penaeus (Melicertus) latisulcatus]. This information was used to evaluate the trade‐off between larval recruitment and catch during fishing periods that demand high prices but coincide with spawning. Total rates of larval settlement were maximized when tidal currents and atmospheric physical‐forcing components were coupled with simulations of larval swimming behaviour under average gulf temperatures. Average gulf temperatures sustained longer larval durations and increased larval settlement rates by over 12% compared with warmer gulf conditions simulated under a scenario of global warming. Reproductive data coupled with outputs from the biophysical model identified consistent inter‐annual patterns in the areas contributing to larval settlement success. Areas located in the north‐east, and central‐west of the fishery, consistently contributed to over 40% of all larvae reaching a settlement in each year. Harvest sensitivity analyses indicated that changes in the spatial patterns of pre‐Christmas fishing could lead to improvements in overall rates of the larval settlement while maintaining or improving the levels of catch. Future studies to refine the model inputs relating to physical processes, larval behaviour and mortality rates for P. latisulcatus coupled with surveys of juvenile prawn abundance to ground truth the modelled predictions, would allow stock recruitment relationships to be more closely examined and inform adaptive management of the fishery in the future. 相似文献
104.
Grondin TM DeWitt SF Keeton KS 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(3):306-310
Abstract Abstract: A 9‐year‐old Arabian mare was evaluated for a 7‐day history of malaise. Results of a CBC included a leukocyte concentration within the reference interval (8.4 × 103/μL, reference interval 6.0–14.0 × 103/μL) with an apparent degenerative left shift (segmented neutrophils 1.2 × 103/μL, reference interval 2.5–7.5 × 103/μL; hyposegmented neutrophils 1.8 × 103/μL, reference interval 0.0–0.2 × 103/μL). Serum clinical chemistry results included increased aspartate transaminase, alkaline phosphatase, and gamma‐glutamyltransferase activities. A presumptive diagnosis of hepatitis or cholangiohepatitis was made. The horse was treated with antimicrobials and the malaise quickly resolved. However, in a recheck CBC on day 13, the apparent degenerative left shift remained. Further evaluation of the blood smear revealed many hyposegmented granulocytes with coarse mature chromatin and normal cytoplasmic features. On the basis of the microscopic examination, the horse was diagnosed with Pelger‐Huët anomaly. The patient's offspring was subsequently also diagnosed with Pelger‐Huët anomaly on the basis of blood film examination. Neutrophil, eosinophil, and basophil mean nuclear scores in both affected horses (mare, range 1.5–2.6; offspring, range 1.6–3.2) were lower than those in 2 unrelated Arabian horses (range, 2.8–5.0) and 5 non‐Arabian control horses (range, 2.8–5.0). Results of immunophenotyping and phagocytosis/oxidative burst assays via flow cytometry showed no difference in the expression of myeloid–specific or adhesion molecules or in neutrophil function between affected and control horses. This is the second known report of equine Pelger‐Huët anomaly, both of which affected Arabian horses. 相似文献
105.
Juvenal Kanani Dirk Philipp Kenneth P Coffey Elizabeth B Kegley Charles P West Shane Gadberry John Jennings Ashley N Young Robert T Rhein 《畜牧与生物技术杂志(英文版)》2015,6(1)
Background
The effect of time of fecal sampling on the accuracy of acid-detergent insoluble ash (ADIA) and alkaline-peroxide lignin (APL) for the prediction of fecal output (FO) in cattle was evaluated. Eight ruminally cannulated cows (594 ± 35.5 kg) were allocated randomly to 4 bermudagrass [Cynodon dactylon (L.) Pers.] hay diets markedly different in crude protein concentration (79–164 g/kg) with 2 replicates per diet for 3 periods. Cows were offered hay individually at 20 g DM/kg of body weight daily in equal feedings at 08:00 and 16:00 h for a 10-d adaptation period followed by 5-d of total fecal collection. Fecal grab samples also were taken each day during the fecal collection period at 06:00, 12:00, 18:00, and 24:00 h either directly from the rectum or from freshly voided feces. Samples were composited within cow and time across the 5 d total fecal collection period. Additionally, forage, ort, and fecal samples were analyzed for concentrations of APL and ADIA.Results
Fecal concentrations of ADIA and APL were not affected by sampling time (P ≥ 0.22), even though diet affected (P < 0.01) fecal ADIA and APL concentrations. There were no diet × sampling time interactions (P ≥ 0.60). Estimates of FO and dry matter digestibility (DMD) from ADIA and APL were not affected (P ≥ 0.16) by sampling time or the diet × sampling time interaction (P ≥ 0.74). Estimates of FO and DMD from markers from different sampling times or all different combinations of sampling time were not different (P ≥ 0.72) from those of total collection among internal markers.Conclusion
Little variation in concentrations of ADIA and APL in daily fecal excretion across time increases flexibility in fecal grab sampling schedules for predicting FO and DMD. 相似文献106.
Jasmeen Sidana Rajesh K. Rohilla Nilanjan Roy Russell A. Barrow William J. Foley Inder Pal Singh 《Fitoterapia》2010
Loxophlebal A, a new antibacterial formylated phloroglucinol was isolated from the mother liquor obtained after separation of sideroxylonals from the chloroform–methanol extract of leaves of Eucalyptus loxophleba ssp lissophloia. The structure of loxophlebal A was determined to be 3-desformyl sideroxylonal A by spectroscopic methods including 1D- and 2D-NMR. The stereochemistry of loxophlebal A was determined by chemical correlation with sideroxylonal A. This article also reports an efficient, simple and economic method for large scale isolation of sideroxylonals in a purity of > 90% from the leaves of Eucalyptus loxophleba ssp lissophloia. 相似文献
107.
We evaluated winter (January through March) carbon assimilation of red spruce (Picea rubens Sarg.) from three Vermont seed sources grown in a common garden in northwestern Vermont. Although CO(2) exchange rates were generally low, net photosynthetic rates increased during two prolonged thaws. Significant correlations between CO(2) exchange rates and multiday air temperature means supported our observations of enhanced gas exchange during extended periods of elevated temperature. Increases in photosynthesis during thaws occurred before observed increases in leaf conductance, indicating that initial changes in photosynthesis were probably not associated with changes in stomatal aperture. Results of correlations between photosynthetic rates and PAR suggested that solar irradiance did not have a strong effect on winter carbon capture. Rates of net photosynthesis differed among seed sources. Trees from the Mt. Mansfield source had the highest average rates of photosynthesis and, at times, rates for individual trees from this source approximated those occurring during the growing season. Because seed sources differed in photosynthetic rates but not in leaf conductance, we conclude that differences in winter photosynthesis among seed sources were primarily attributable to factors other than changes in stomatal aperture. 相似文献
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