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排序方式: 共有251条查询结果,搜索用时 15 毫秒
1.
Maryam Mirderikvandi Heshmatollah Khosravinia Bahman Parizadian Kavan 《Journal of animal physiology and animal nutrition》2020,104(1):166-177
Two hundred fifty two male Ross 308 broiler chicks were raised to examine the effects of Satureja khuzistanica essential oils (SkEO; 0, 200, 300, 400, 500 and 600 mg/bird/day) administrated via oral gavage and dietary supplementation of acetic acid (AA; 0 or 20 g/kg) in a 6 × 2 factorial fashion using a complete randomized block design with seven replicates of three birds each. In Day 34 of age, liver fat percentage decreased by increasing SkEO levels in a quadratic trend (p < .05). Oral gavag of 200 and 300 mg of SkEO decreased AST activity by 16.67% and 16.94%, respectively, compared with the control birds (p < .05). In Day 38 of age, liver percentage was greater by 0.37% in the birds received 400 mg SkEO than those given 500 mg (p < .05). Liver fat percentage decreased in the birds fed the acidified diet and received 300 and 500 mg SkEO as well as in the birds offered 200 and 400 mg of SkEO and fed non-acidified diet than those received acidified diet with no SkEO administration (p < .05). Prevalence of score zero for hepatocytic vacuolations and necrosis was 80.00% and 42.42% in the birds receiving 600 mg SkEO respectively. Median for relative frequency of scores for hepatocytic vacuolations and hepatocytic necrosis was lesser in the birds received SkEO by oral gavage compared with that of control birds (p < .05). In conclusion, administration of SkEO via oral gavage reduced liver fat in broiler chicken but no consistent dosage could be verified as the effective dosage for all ages concerned. The acidified diet per se showed no evident effect on liver fat at all ages considered. The SkEO × AA interaction exhibited promising but unreliable effects on liver colour score in market age (42 days). 相似文献
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Comparative effects of Shirazi thyme and vitamin E on some growth and plasma biochemical changes in common carp (Cyprinus carpio) during cadmium exposure
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Mohammad Mohiseni Maryam Sepidnameh Dara Bagheri Mahdi Banaee Behzad Nematdust Haghi 《Aquaculture Research》2017,48(9):4811-4821
Phytobiotics include a large number of active components which potentially have a growth‐promoting effects and antioxidant properties. This study was conducted to investigate the protective effects of Shirazi thyme and vitamin E on growth and plasma biochemical parameters of common carp exposed to cadmium. Fish (34 ± 3 g) were divided into four groups and fed four distinct diets including commercial diet without any additive (for control and metal only group) and supplemented with either 1% ground Shirazi thyme or 100 mg kg?1 vitamin E for 45 days. At the end of the feeding trial, all treatments except control group were exposed to sub‐lethal concentration of waterborne cadmium for 15 days and sampling was done on days 0, 7 and 15 after the metal exposure. According to the results, dietary inclusion of thyme prevented the harmful effects of cadmium and also improved fish growth and nutritional indices including weight gain, feed conversion ratio, specific growth rate and condition factor. Results also revealed that Shirazi thyme was more effective than vitamin E. Similarly, no changes in the hepatosomatic, viscerosomatic and bile somatic indices were observed. Plasma enzymes (AST, ALT, ALP and LDH) and metabolites were not altered due to thyme supplementation compared to the control. In conclusion, dietary supplementation of 1% ground Shiraz thyme improved the growth and health status of fish and showed better hepatorenoprotective properties than vitamin E during waterborne cadmium exposure in common carp juveniles. It might be conceivable to consider Shirazi thyme as a potential phytobiotic for incorporation in fish diet. 相似文献
4.
Amin Oujifard Jafar Seyfabadi Abdolmohammad Abedian Kenari Masood Rezaei 《Aquaculture International》2012,20(1):117-129
Replacement of fish meal (FM) with rice protein concentrate (RPC) as a practical diet for the Pacific white shrimp, Litopenaeus vannamei, was evaluated. Five isonitrogenous (36.6% protein) diets, formulated by replacing 0, 25, 50, 75, and 100% of FM by RPC,
were fed to shrimp (initial weight of 6.99 ± 0.08 g) five times daily to satiation for 60 days. Relatively high final weight
(FW 17.64–18.25 g) and weight gain (WG 10.81–11.39 g) were obtained in treatments up to 50% of the plant protein inclusion.
Above this inclusion level, FW (14.93–14.35 g) and WG (7.68–7.23 g) were reduced. Survival was high (≥95%) and similar for
all diets. There were no significant differences (P > 0.05) in tail-muscle composition (moisture, protein, lipid, and ash) among different dietary treatments. Dispensable and
indispensable amino acids of the tail muscle of shrimp fed with 25, 50, and 75% RPC were significantly higher than the FM
(0%) and 100% RPC diets. A decreasing trend in apparent digestibility coefficient (excluding dry matter) for crude protein
(90.52–52.41), ether extract (94.11–80.03), organic matter (87.25–50.16), and gross energy (89.41–55.24) was observed at higher
RPC inclusion rates. The results suggest that RPC meal can be a potential candidate for FM replacement up to 50% of the protein
in shrimp diets. 相似文献
5.
H. Khosravi S. M. Samar E. Fallahi H. Davoodi M. Shahabian 《Journal of plant nutrition》2013,36(6):946-953
ABSTRACT Roots of young ‘Golden Delicious’ apple on M9 rootstock were inoculated with four strains of Azotobacter chroococcum, which were isolated from various soils. Effects of these strains in combination with different levels of nitrogen (N) fertilizer and compost on plant growth and nutrient uptake were studied over two seasons. Therefore, a factorial arrangement included four strains of A. chroococcum, two levels of N-fertilizer (0 and 35 mg N kg?1soil of ammonium nitrate) and two levels of compost (0 and 12 g kg?1 soil of air-dried vermicompost). Among the four strains, AFA146 was the most beneficial strain, as it increased leaf area, leaf potassium (K), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn), and boron (B) uptake and root N, phosphorus (P), potassium (K), Mn, and Zn. The combination of AFA146 strain, compost and N fertilizer increased leaf uptake of Ca, Mg, Fe, Mn, Zn, and B, and root uptake of P, K, Ca, Mg, Mn, and copper (Cu), and root dry weight. 相似文献
6.
Maryam Zahedifar Somayeh Dehghani Edris Gavili 《Archives of Agronomy and Soil Science》2017,63(1):136-149
Continuous application of sewage sludge (SS) as a source of organic matter, may increase available heavy metals (HMs) up to their critical levels. As a consequence their uptake by plants, risks of accumulation in food chain and groundwater pollution increases. To evaluate the effects of perlite and SS on total content and available fraction of iron (Fe), manganese (Mn), lead (Pb), copper (Cu), nickel (Ni), cadmium (Cd) and zinc (Zn) over 45 and 90 days a completely randomized pot experiment was conducted. Treatments consisted of SS (0, 2 and 4%) and combined SS and perlite levels (1:1, 1.5:0.5 and 0.5:1.5% SS:perlite). Mean available Fe, Ni, Cd, Mn and Zn fractions decreased over time by 7–27%, whereas, total contents did not change. Available HMs in SS-treated soils increased by 0.5–25%; whereas, only total Zn, Cu and Pb concentrations increased with SS application (although concentrations fall in the range of critical levels). The lowest (1.6 fold) and highest (22.1 fold) increases obtained for available Cu and Zn, respectively. Perlite could mitigate the adverse effect of high rate application of SS on amplification of HMs extractability. Therefore, their concomitant applications can be suggested considering the perlite durability and its positive effects on soil physical properties. 相似文献
7.
Sodium adsorption ratio (SAR) is one of the water quality indexes that whose is important due to reuse or depletion to environment. Solutes in drain water can be controlled by adsorption, chemical or biological reaction, organic envelope of drainage. Rice husk is the common option of drainage envelops in paddy fields. In this study, the ability of reduction of SAR by rice husk was evaluated in batch scale and physical model of drain envelops. In the batch experiments, the adsorption of SAR parameters was investigated by adding 2 g of rice husk into a 100 ml of sodium chloride solution. The results indicated that rice husk absorbed calcium, magnesium and sodium, respectively. By increasing the temperature, contact time and pH, adsorption of calcium, magnesium and sodium was increased; however, the higher concentration of sodium in soil solution reduced the percentage of adsorption. In a more realistic state, physical models of subsurface drainage in the paddy fields were made. Drainage envelope treatments included of rice husk (H), combination of 20 and 60 % of husk with gravel (H20G80 and H60G40) and a pipe without envelope (NE). Due to higher drain discharge and more sodium removal (lower SAR in drain water), treatment H with the discharge of 16.2 ml/min and SAR of 1.27 (meq/l)0.5 was better in comparison with other treatments. 相似文献
8.
Maryam Aflaki Jalali Hassan Bahrami Sirmandi Abdullah Hatamzadeh 《Journal of Crop Science and Biotechnology》2017,20(1):29-35
Low efficiency of somatic embryo maturation, germination, and conversion to plantlets is a major problem in many species including J. regia L. Germination efficiency of somatic embryos is very low in walnut. In this study, effects of two carbohydrate sources, sucrose and maltose (each at 3% and 6%), and two kinds of PEG (4000 and 6000) (each at four levels of 1.5%, 3%, 5% and 7.5%) on maturation and germination of walnut embryos were tested. The number of somatic embryos increased conspicuously on medium containing PEG. Furthermore, higher levels of PEG-4000 (7.5%) could remarkably enhance the morphogenesis of somatic embryos and the number of embryos produced. PEG-4000 stimulated somatic embryo maturation of walnut. This stimulatory effect was dependent on the carbohydrate source used. Sucrose in combination with PEG-4000 produced 50% of cotyledonary and normal somatic embryos. Different concentrations of PEG were effective on the number of embryos with a shoot meristem. PEG-4000 7.5% and sucrose 3.0% produced the highest rate (50.0%) of normal shooting embryos. However, PEG (4000, 6000) and maltose caused an unfavorable effect and increased the frequency of abnormal shaped somatic embryos. 相似文献
9.
Herd-level prevalence of Mycobacterium avium subspecies paratuberculosis by bulk-tank milk PCR in Fars province (southern Iran) dairy herds 总被引:1,自引:0,他引:1
Haghkhah M Ansari-Lari M Novin-Baheran AM Bahramy A 《Preventive veterinary medicine》2008,86(1-2):8-13
A cross-sectional study was conducted from March to August 2006 in dairy herds in Fars province, southern Iran to determine the herd-level prevalence of Mycobacterium avium subspecies paratuberculosis (MAP) infection. Bulk-tank milk samples were collected from 110 dairy herds in the 3 districts (Shiraz, Marvdasht and Sepidan) of the province. Among study populations, 12 herds (11%, 95%CI: 5-17%) were positive for MAP infection based on IS900 nested PCR. The prevalence of positive milk samples in the three districts of Fars province was different ranging from 8.6% to 23% which was not statistically significant (P=0.19). It is recommended to conduct further epidemiologic studies to determine cow-level prevalence and risk factors for infection, and to evaluate the economic consequences of the MAP infection in the region. 相似文献
10.
Maryam Haghighi Mohsen Kafi Atena Sheibanirad Mohammad Reza Sharifinia 《Journal of plant nutrition》2016,39(10):1460-1471
Ornamental kale (Brassica oleracea var. Acephala) is usually planted from early autumn until late winter. Since most of the plants used for phytoremediation cannot be grown during this time, kale can be a suitable option for phytoremediation and utilized during autumn and winter in urban landscape, especially in metropolitan areas where high levels of cadmium (Cd) and lead (Pb) pollutions exist. Kale growth in saline soil at different growth stages (germination and vegetative growth stages) was studied in this investigation. A factorial experiment based on completely randomized design (CRD) with four replications was used in this study. Treatments included three levels of sodium chloride (NaCl) (0, 30, and 60 mg/kg), four levels of Cd (0, 4, 8, and 16 mg/kg), and four levels of Pb (0, 1, 5, and 10 mg/kg). Results indicated that increase in Cd and Pb concentrations in the soil decreased fresh and dry weights of the plants. The results of the various growth stages revealed that under salinity stress, kale plants were able to absorb more Pb than Cd and effectively remediate Pb in polluted and saline lands. Cd accumulation in control treatment was 6.2% more than that in the saline treatments, whereas, Pb accumulation in the highest NaCl level, 60 mg/kg salinity treatment was 7.64% more than that of the control condition. Also, proline content of the plants was significantly increased under Cd and Pb stress. From the results of this study, it was concluded that using kale plant is recommended for phytoremediation of saline soils with 10 and 16 mg/kg Pb and Cd contents, respectively. 相似文献