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Sharkey LC DeWitt S Stockman C 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(2):254-258
A 23-year-old Thoroughbred gelding was referred for the evaluation of acute onset of ataxia and depression, and a 2-day history of fever. On physical examination, the gelding was profoundly depressed and 10-12% dehydrated. The horse appeared very unstable, with a wide-based stance in the hind limbs, severe symmetric ataxia in all 4 limbs, and proprioceptive deficits in both hind limbs. Nasogastric intubation produced 4 L of brown, fetid reflux, and rectal examination revealed mild small intestinal and cecal distention. Hematologic abnormalities included neutropenia with toxic change, compatible with acute inflammation and endotoxemia, and prolonged coagulation times. Serum biochemical abnormalities included prerenal azotemia. metabolic acidosis, and electrolyte abnormalities consistent with enteritis. Blood ammonia concentration was markedly increased (406 micromol/L; reference interval 4-49 micromol/L), however, serum bile acids concentration and hepatic enzyme activities were within reference intervals. Histopathologic examination of a liver biopsy revealed no abnormalities and results of tests for several infectious agents were negative. Clinical signs resolved with correction of the dehydration and electrolyte abnormalities and with antibiotic therapy. The horse was diagnosed with hyperammonemic neuropathy associated with gastrointestinal disease. In such cases, hyperammonemia is caused by increased production of ammonia by organisms in the gastrointestinal tract in combination with increased gut permeability that facilitates ammonia absorption. 相似文献
105.
Ultan Mc Carthy Gashaw Ayalew Francis Butler Kevin McDonnell Shane Ward 《Computers and Electronics in Agriculture》2009,69(2):135-141
Undetected RFID tags make the potential benefits of RFID unattainable. This study aimed to determine the most significant factors that affect RFID and particularly its application to the traceability of meat. Experimental parameters included five RFID tag inlays, two levels of conveyor speeds, five variations of beef sample and an empty container, 12 tags per test sample, three distances and two types of reader antenna polarisations. Tag detection rates were determined in three replicates per combination of test parameters. A GLM ANOVA was carried out on tag detection rate. In decreasing order of significance in terms of the effect on mean tag detection rate were distance, sample, inlay design, conveyor speed and reader antenna polarisation. Interaction of these factors also proved significant, in decreasing order of importance were reader antenna * inlay, sample type * distance, inlay * distance, sample type * inlay, sample type * reader antenna, distance * speed, sample type * speed and finally sample type * distance * speed. Linearly polarised antenna preformed better overall at detecting tags, with 63% mean detection rate compared with circularly polarised antenna with 57% mean detection rate. Varying the tag inlay resulted in mean detection rates of between 62% and 88%. Ideal transponder location on package was reader antenna polarisation dependent, but generally tags facing reader antennas exhibited better detection rate. Results revealed that the under side of the package was the most un-detectable transponder location, considering the placement of reader antennas on top, left and right sides of the sample. Conveyor speed also proved significant with a variation from 0.5 to 1.0 m/s resulting in an average detection rate ranging from 62% to 57%, respectively. Circularly polarised antennas are believed to perform better in cases of random tag orientation on products. It can be concluded that RFID systems implementation in the meat supply chain requires a holistic approach where distances, polarisations, inlay type, meat composition and conveyor speed need to be considered. 相似文献
106.
Dusty L. McDonald Paul D. Cason Britt W. Bumguardner Shane Bonnot 《Journal Of Applied Aquaculture》2013,25(4):308-319
The critical thermal maximum of juvenile spotted seatrout (SL range 18–33 mm) was determined using a temperature increase of +0.26°C per hour. The critical thermal maximum (water temperature that was lethal to 50% of the test fish [LT50]) for trial 1 was LT50 = 38.8°C, LT50 = 39.4°C for trial 2, and LT50 = 38.9°C for trial 3. Critical thermal maximums differed significantly (P < 0.05) between trials 2 and 3, whereas trial 1 did not differ among trials. This difference correlated with body size, where fish in trial 2 were significantly larger (P < 0.05) (mean = 27.6 ± 2.0 mm in SL) (mean ± SE) than the fish of trials 1 (mean = 23.1 ± 0.5 mm in SL) and 3 (mean = 21.5 ± 0.7 mm in SL), suggesting positive size dependence in the critical thermal maximum. 相似文献
107.
D. Shane Hennigh Kassim Al-Khatib Randall S. Currie Mitchell R. Tuinstra Patrick W. Geier Phillip W. Stahlman Mark M. Claassen 《Crop Protection》2010
The recent development of grain sorghum hybrids with resistance to acetolactate synthase (ALS)-inhibiting herbicides has allowed for the use of several post-emergence applied (POST) ALS-inhibitors to control weeds in the crop. Field experiments were conducted at four sites in Kansas in 2008 to evaluate the efficacy of nicosulfuron and nicosulfuron + rimsulfuron applied alone or in combination with dicamba, metsulfuron methyl, and atrazine. All POST treatments slightly injured sorghum 2 weeks after treatment (WAT) at Garden City and Hesston, whereas at Hays and Manhattan, only treatments that included dicamba caused injury. Nicosulfuron + rimsulfuron applied alone provided 41, 83, 74, and 93% control of grasses 4 WAT at Garden City, Hays, Hesston, and Manhattan, respectively. However, to obtain the highest level broadleaf weed control, nicosulfuron or nicosulfuron + rimsulfuron need to be applied with other broadleaf herbicides. POST treatment of nicosulfuron + metsulfuron methyl + dicamba + atrazine provided 90% or greater control of all broadleaf weeds at sorghum flowering. Sorghum grain yield was greater following all herbicide treatments compared with the weedy check. The POST treatment that provided the highest yield at Garden City was nicosulfuron + rimsulfuron + atrazine, whereas in Hesston and Manhattan, nicosulfuron + metsulfuron methyl + dicamba + atrazine provided the highest yields. This research showed that many grasses can be effectively controlled with POST applications of nicosulfuron or nicosulfuron + rimsulfuron in ALS-resistant sorghum. The research also indicated that broadleaf weed control is greater when nicosulfuron or nicosulfuron + rimsulfuron are applied with other broadleaf-control herbicides such as dicamba, metsulfuron methyl, and atrazine. 相似文献
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109.
Kaiwen Pan Zhihong Xu Timothy J. Blumfield Shane Tutua Manxin Lu 《Journal of Soils and Sediments》2009,9(6):515-525
Purpose
Hoop pine (Araucaria cunninghamii) is a nitrogen (N)-demanding native Australian softwood plantation species. Litter quality and its effects on soil mineral N and 15N transformations have not been well studied in the hoop pine plantation and adjacent native forest. The present study was conducted to determine the impact of 15N injection depth and litter additions on the dynamics and fate of mineral 15N and also to compare the difference in litter quality, 15N dynamics, and fate between the hoop pine plantation (HP) and the adjacent native forest (NF).Materials and methods
The experiments were done in the Yarraman State Forest (26°52′ S, 151°51′ E), southeastern Queensland. Materials of litter addition were prepared on the basis of ten random samples of litters taken from the NF and HP sites using a 1?×?1-m quadrat. Litter additions were defined as: SL represented the average condition of forest floor in the forest ecosystems and DL represented the double average amount of litters in the forest ecosystem. Experiment 1 covered 2 forest types (NF and HP)?×?3 litter rates (nil litter, SL, and DL)?×?3 15N injection depths (0, 2.5, and 5.0 cm). Experiment 2 included 2 forest types (NF and HP)?×?2 litter rates (nil litter and SL)?×?3 injection depths (0, 2.5, and 5.0 cm) of distilled water. The in situ core incubation method was used with an incubation period of 28 days. The isotope ratio of mineral N or/and total N (soil and litter) were analyzed using an isotope ratio mass spectrometer with a Eurovector elemental analyzer (Isoprime-EuroEA 3000).Results
Total N and δ 15N were significantly higher, and C/N ratios and δ 13C were significantly lower in the NF litters than in the HP litters. The NF litters had significantly lower total 15N and total 15N recovery than the HP litters after 15N addition. Litter addition had no significant effect on mineral 15N transformations and δ 15N in the NF soil, but decreased 15NO 3 ? –N, mineral 15N, and δ 15N and increased immobilized 15N in the HP soil. The depth of added 15NH 4 + significantly altered total 15N, δ 15N, and total 15N recovery in the litters, whereas it did not influence 15NH 4 + –N, 15NO 3 ? –N, mineral 15N, or immobilized 15N in soils in the two forest ecosystems.Discussion
The NF litters had significantly higher δ 15N than the HP litters, indicating that the NF soil had a higher rate of nitrification than the HP soil. Higher litter quality in the NF was an important driving force for N cycling to promote strong N dynamics in the NF soil over the HP soil. The HP litters had significantly higher total 15N than the NF litters after 15N addition, implying that soil mineral N was relatively deficient in the HP in comparison with the NF. Litters decreased nitrification and increased immobilization in the HP soil, showing forest litters resulted in more N immobilization to prevent the loss of substantial quantities of NO 3 ? through leaching or denitrification. The depth of 15N injection did not significantly alter concentrations of 15NH 4 + –N, 15NO 3 ? –N, mineral 15N, and immobilized 15N in the NF and HP soils, suggesting that the depth of 15N injection had no significant influence on the evaluation of soil N transformations.Conclusions
The NF litters had significantly higher total N and δ 15N and lower C/N ratios and δ 13C than the HP litters. Mineral N was relatively insufficient in the HP soil relative to the NF soil. The HP litters facilitated more N immobilization in the soil to reduce the loss of substantial quantities of NO 3 ? through leaching or denitrification. The depth of 15N added did not significantly alter concentrations of 15NH 4 + –N, 15NO 3 ? –N, mineral 15N, and immobilized 15N in the NF and HP soils. The application of 15N solution by uniform sprinkling onto the soil surface can be used to study in situ field N (including mineral 15N) transformations in the 10-cm depth soils of both forest ecosystems. 相似文献110.
F. Kidd C. West D. G. Griffiths N. A. Potter 《The Journal of Horticultural Science and Biotechnology》2013,88(3):179-191
The volatile oil contents of dried leaves of Majorana hortensis, Melissa officinalis, Ocimum basilicum, Origanum vulgare, Salvia officinalis and Thymus vulgaris reached maximum values in summer. Different harvest dates are required in order to obtain the highest yields of dried leaves ha-1, the highest levels of volatile oil in the dried leaves, and the highest yields of volatile oil ha-1. The upper parts of balm, oregano and sage plants yielded the most dried leaves, but the lower parts showed the highest levels of volatile oil in the dried leaves. 相似文献