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71.
The effect of two different diet types (concentrate feed+hay and grazing) on the pharmacokinetic profiles of triclabendazole following oral administration in goats was investigated. A total of 12 goats were randomly allocated into two groups which were either indoor and fed concentrate + hay ration (housed group) or were grazing on pasture (grazing group). Triclabendazole was administered orally to animals in two groups at 10 mg/kg bodyweight. Blood samples were collected from 1 h to 192 h post-treatment and analyzed by high performance liquid chromatography (HPLC). Feeding with different diets significantly effected the plasma disposition of triclabendazole sulphoxide. Maximum plasma concentration (C(max): 13.22+/-2.81 microg/ml), time to reach maximum plasma concentration (t(max): 18.4+/-2.19 h), area under the curve (AUC: 613+/-137 microg h/ml), half-life (t(1/2): 24.77+/-1.94 h) and mean resident time (MRT: 40.22+/-4.36 h) of triclabendazole sulphoxide in housed group were significantly different from those of grazing group (C(max): 10.17+/-1.51 microg/ml, t(max): 14.0+/-2.19 h, AUC: 406+/-98 microg h/ml), t(1/2): 16.16+/-1.17 h and MRT: 34.48+/-4.40 h). It is concluded that anthelmintically more active sulphoxide metabolite has higher plasma concentration when triclabendazole is administered to goats fed with concentrate feed + hay compared to grazing goats.  相似文献   
72.
Sea bream, Sparus aurata, is one of the most important fish species that is commonly cultured in the Mediterranean and the eastern coasts of the Atlantic Ocean. The life cycle of sea bream in its natural habitat passes through hyposaline and hypersaline lagoons. It is important to determine the tolerance of the fish to nitrogenous compounds for aquaculture at maximum stocking densities. In the present study, a series of acute experiments were performed to evaluate the effect of salinity on ammonia and nitrite toxicity to sea bream. The fish were exposed to different ammonia and nitrite concentrations according to the static renewal methodology at three different salinities (10, 20, and 30 ppt) and at a temperature of 20 C and a pH of 8.2. The toxic effect of total ammonia nitrogen (TAN) and nitrite nitrogen (NO2‐N) decreased with increasing salinity levels (P < 0.001). Acute toxicity (96‐h lethal concentration 50 [LC50]) values of TAN were determined to be 5.93, 11.72, and 19.38 mg/L at 10, 20, and 30 ppt salinity, respectively. The 96‐h LC50 values of NO2‐N were determined to be 370.80, 619.47, and 806.33 mg/L at 10, 20, and 30 ppt salinity, respectively. Results indicate that sea bream is less tolerant to ammonia but more tolerant to nitrite compared with some other fish species.  相似文献   
73.
High concentrations of boron (B) in the soil, reduces plant growth, crops’ yield and quality. Regarding such problem, synergistic and antagonistic relations between the nutrients can be used to ameliorate the B toxicity. Therefore, a greenhouse experiment was conducted to evaluate effects of soil-applied zinc (Zn), nitrogen (N), calcium (Ca), lime (CaCO3), potassium (K), humic acid (HA), and humus on the dry weight and B uptake of maize shoots (Zea mays L.) under high-B containing soil conditions. Increasing doses of B (0, 2.5, 5, and 10 mg kg?1 B) were applied to soil as borax (Na2B4O710H2O), and boric acid (H3BO3). Positive correlations were found between B doses and the uptake amounts (r = 0.934**; – 0.964**). However, the correlations between the dry weight and B doses (r = ?0.314**; – r = ?0.495**) and between the dry weight and the uptake amounts (r = ?0.294*; – r = ?0.497**) were negative. Among the materials, Zn and humus exhibited positive correlations with dry weight values (r = 0.249*; r = 0.525**), and an effective increase (p < 0.01) in the dry weight amounts of maize shoots was observed under toxic B conditions.  相似文献   
74.
75.
This study was focused not only at the assessment of effects of different sewage sludge application rates on vegetative parameters and yield of raspberry (Rubus ideaus L.) but also heavy metal accumulation in the soil and raspberry leaves. A three-year field study was set up in a completely randomized block design with five sewage sludge application rates (0.0, 2.5, 5.0, 7.5 and 10.0?kg of dry matter per plant) and three replications. One-year-old, virus free ‘Heritage’ saplings were used for the experiment. The results of this study clearly indicated that the sewage sludge application is an effective mean for improvement of vegetative growth, yield, soil and plant chemical properties of raspberry in light textured soils. In addition to macro-element contents, sewage sludge application also caused significant changes in micro-element content of soils. No adverse effects of these increases were observed on plants throughout the experimental period. The most effective application rate was found as 7.5?kg per plant for this ecological condition. It can be concluded that when properly treated and applied to farmland sewage sludge is not only disposed economically but also improved vegetative growth and yield of raspberry.  相似文献   
76.
A tumor-like tissue mass of lateral-limbal site in the right eye of a 12-year-old Cob Pony mare was presented for surgical removal. The mass, covering the lateral limbus, bulbar conjunctiva and part of the cornea, was surgically removed, and the corneal defect repaired with a pedicle bulbar conjunctival graft. The mass was inflammatory in nature containing mononuclear cells. No recurrence or complication occurred at 6- and 12-month follow-up examination.  相似文献   
77.
Clinical and magnetic resonance imaging (MRI) findings, histological appearances and surgical outcomes of 18 dogs and one cat with spinal tumors are presented. Medical records of the cases admitted for spinal disorders were reviewed, and cases of spinal tumors that were diagnosed by MRI and confirmed by histological examination were included in this study. T1 weighted, T2 weighted and contrast enhanced T1 weighted images were taken and interpreted to evaluate the spinal tumors. The tumors were diagnosed as: meningioma (n = 6), ependymoma (n = 1), nerve sheath tumor (n = 4), metastatic spinal tumor (n = 3), osteosarcoma (n = 2), osteoma (n = 1), rhabdomyosarcoma (n = 1), and nephroblastoma (n = 1). Thirteen cases underwent surgical operation and the remaining six cases were euthanized at the request of the owners. The neurological status of the surgical cases did not deteriorate, except for one dog that showed ependymoma in the early period after the operation. These results indicate the potential for surgical gross total tumor removal of vertebral tumors to provide better quality of life and surgical collection of histological specimens for definitive diagnosis. For effective case management, dedicated MRI examination is important to accurate evaluation of the spinal tumors, and surgical treatment is useful for extradural and intradural-extramedullary spinal tumors.  相似文献   
78.
不同植被对土壤理化性质影响——以王东沟小流域为例   总被引:2,自引:1,他引:2  
[目的]分析陕西省长武县王东沟流域9个径流小区不同植被覆盖条件对土壤理化性质的影响,为黄土高原生态建设提供科技支持。[方法]采用环刀法、定水头法以及重铬酸钾外加热法等分层测定0—40cm间土壤容重、毛管持水量、饱和持水量、饱和倒水率以及有机质含量。[结果]饱和持水量、毛管持水量、土壤有机质表现为草、灌地显著优于纯林和混交林,而土壤容重、饱和导水率各小区间差异不显著。[结论]草地和沙棘灌木林地土壤理化性质高于其他植被组合,培肥土壤,涵养水源,利于保水保土。侧柏纯林的土壤理化性质最差,水保效益最低。  相似文献   
79.
Monounsaturated fatty acids (MUFA)-rich and n-6 polyunsaturated fatty acid (n-6 PUFA)-rich vegetable oils are increasingly used as fish oil replacers for aquafeed formulation. The present study investigated the fatty acid metabolism in juvenile European sea bass (Dicentrarchus labrax, 38.4 g) fed diets containing fish oil (FO, as the control treatment) or two different vegetable oils (the MUFA-rich canola/rapeseed oil, CO; and the n-6 PUFA-rich cottonseed oil, CSO) tested individually or as a 50/50 blend (CO/CSO). The whole-body fatty acid balance method was used to deduce the apparent in vivo fatty acid metabolism. No effect on growth performance and feed utilization was recorded. However, it should be noted that the fish meal content of the experimental diets was relatively high, and thus the requirement for n-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA) may have likely been fulfilled even if dietary fish oil was fully replaced by vegetable oils. Overall, relatively little apparent in vivo fatty acid bioconversion was recorded, whilst the apparent in vivo β-oxidation of dietary fatty acid was largely affected by the dietary lipid source, with higher rate of β-oxidation for those fatty acids which were provided in dietary surplus. The deposition of 20:5n-3 and 22:6n-3, as % of the dietary intake, was greatest for the fish fed on the CSO diet. It has been shown that European sea bass seems to be able to efficiently use n-6 PUFA for energy substrate, and this may help in minimizing the β-oxidation of the health benefiting n-3 LC-PUFA and thus increase their deposition into fish tissues.  相似文献   
80.
The aim of the present study was to determine the vitamin D status in cattle with malignant catarrhal fever (MCF). Twelve cattle diagnosed as MCF and 6 healthy cattle (controls) were used in the study. Serum 1,25-dihydroxyvitamin D(3) (1,25-D), 25-hydroxyvitamin D(3) (25-D), calcium, phosphorus and parathyroid hormone (PTH) levels were determined as 96.83 pg/ml, 30.0 ng/ml, 2.19 mmol/l, 1.57 mmol/l and 15.21 pg/ml in MCF group and 42.33 pg/ml, 37.0 ng/ml, 2.43 mmol/l, 1.96 mmol/l and 36.08 pg/ml in controls, respectively. Although serum 1,25-D level in the MCF group was increased (P<0.01), serum calcium (P<0.01) and PTH (P<0.05) levels were decreased compared to the controls. The results suggest that there might be an interaction between vitamin D status and MCF.  相似文献   
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