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101.
1. A 6-week study was conducted to investigate the effects of phytase and hydroalcoholic extract of Withania somnifera root (WS) on productive performance and bone mineralisation of laying hens in the late phase of production. 2. Diets were arranged factorially (3?×?2?×?2) and consisted of a positive control with adequate Ca (4·37%) and nonphytate P (NPP; 0·39%) and a negative control diet with Ca (4·06%) and NPP (0·36 %); three concentrations of Withania somnifera (0, 65 and 130?mg/kg diet); and two concentrations of microbial phytase (0 and 300 U/kg diet). 3. A total of 144 72-week-old Hy-Line W36 laying hens were randomly assigned to the 12 treatment groups. Each treatment was replicated 4 times (4 x 3 hens). Egg production and egg weight were recorded daily, while feed intake and egg quality traits were recorded every two weeks. Bone quality traits were evaluated at the end of experiment. 4. Withania somnifera supplementation increased egg production and lowered egg weight only in the second two weeks of the experiment. Addition of phytase significantly depressed specific gravity of the eggs for the entire experiment period. No dietary treatment effects were observed on egg shell thickness and yolk weight. 5. Withania somnifera at 130?mg/kg did not affect feed intake. The hens fed on the positive control diet had higher albumen weight than the negative control diet in the second two-week period. Supplementation of the positive control diet with 65?mg/kg Withania somnifera in the absence of phytase significantly improved shell weight compared with the negative control (5·779 vs. 5·273?g respectively). 6. Supplementing Withania somnifera significantly improved Ca and P retention in tibia bone. In addition, an increase in tibia bone P was observed with phytase supplementation. There were significant interactions between Withania somnifera content and phytase for tibia bone Ca and P. 7. The results of this experiment indicated that dietary Withania somnifera has beneficial effects on tibia bone Ca and P content, and phytase improved tibia bone P retention without adverse effects on productive performance. 相似文献
102.
Amara S Abdelmelek H Garrel C Guiraud P Douki T Ravanat JL Favier A Sakly M Ben Rhouma K 《The Journal of reproduction and development》2008,54(2):129-134
The aim of this study was to investigate the antioxidant role of zinc (Zn) in the Cd-exposed testes of Wistar rats. Subchronic exposure to Cd (CdCl(2), 40 mg/l, per os) for 30 days resulted in a significant reduction in growth rate (-11%) and relative weights of testes (-36%) and seminal vesicles (-80%). Treated rats displayed a decrease in testicular and plasma testosterone levels, respectively (-70%, P<0.05; -48%, P<0.05), epididymal sperm count (-22%, P<0.05), and spermatozoa motility (-35%, P<0.05). In contrast, Cd increased the malondialdehyde (+46%, P<0.05), metallothionein (+200%, P<0.05), and 8-oxodGuo concentrations (+71%, P<0.05) in the testis. In the gonad, Cd decreased the GPx (-30%, P<0.05), CAT (-32%, P<0.05), mitochondrial Mn-SOD (-34%, P<0.05), and cytosolic CuZn-SOD (-32%, P<0.05) activities. Zinc supplementation (ZnCl(2), 40 mg/l, per os) in the Cd-exposed rats restored the activities of GPx, CuZn-SOD, and Mn-SOD in the testes to the levels of the control group. Moreover, zinc administration was capable of reducing the elevated levels of malondialdehyde in the testis. Interestingly, zinc supplementation attenuated DNA oxidation induced by Cd in the gonad and restored the testosterone level and sperm count to the levels of the control group. Zinc administration minimized oxidative damage and reversed the impairment of spermatogenesis and testosterone production induced by Cd in the rat testis. 相似文献
103.
104.
Journal of Plant Diseases and Protection - Beet black scorch virus (BBSV) was surveyed in major sugar beet cultivation areas in Iran in 2008–2013 growing seasons. A total of 148 out of 308... 相似文献
105.
The present study aimed to investigate effects of dietary 1,8‐cineole (cineole) on common carp (Cyprinus carpio) health under ammonia toxicity. The fish were fed with four diets supplemented by 0 (control), 0.1 (0.1C), 0.5 (0.5C), and 1 (1C) percent cineole for 2 weeks, before a 24‐hr ammonia exposure. Blood samples were taken before and after ammonia exposure. The results showed that ammonia exposure significantly (p < 0.05) increased serum urea levels, and decreased serum alternative complement (ACH50) activity and serum total immunoglobulin (Ig) levels. Cineole significantly (p < 0.05) increased serum ACH50 activity (0.1% and 0.5% levels) and total Ig levels (0.5% levels). There was no significant difference (p > 0.05) in serum total protein, albumin and globulin levels among the treatments. Before ammonia exposure, there was no significant difference (p > 0.05) in serum alkaline phosphatase (ALP), alanine transaminase (ALT), and lysozyme activities among the cineole treatments. The treatment 0.5C had the lowest lactate dehydrogenase (LDH) and aspartate transaminase (AST) activities before ammonia exposure. After ammonia exposure, serum LDH and ALT activities increased in all treatments, but the treatment 0.5C had the lowest activities. Serum ALP activities increased after the ammonia exposure in the control and 1C groups. Serum AST and lysozyme activities increased after the challenge in all groups except for the 0.5C group. Overall, the results suggest that ammonia exposure causes increase in serum LDH, ALP, AST, and ALT activities and decreased immune responses, which are indicator of tissue damage and immunosuppression. 0.5% cineole is capable to suppress adverse effects of ammonia intoxication in carp. 相似文献
106.
Hamid Rajabiesterabadi Morteza Yousefi Seyyed Morteza Hoseini 《Aquaculture Nutrition》2020,26(3):763-771
The aim of the present study was to evaluate the potential effects of olive leaf (Olea europea L.) extract (OLE) on common carp (Cyprinus carpio) health in response to ambient ammonia toxicity. Fish were fed with experimental diets containing OLE (0, 1, 5 and 10 g/kg) for 60 days followed by a 3‐hr challenge with ammonia (0.5 mg/L unionized ammonia‐N). Results showed that haemoglobin levels, differential leucocyte counts and mean corpuscular haemoglobin concentration were not affected by dietary OLE levels and ammonia challenge. Ammonia challenge significantly increased red blood cells and decreased blood mean corpuscular volume, mean corpuscular haemoglobin, plasma lysozyme, complement and bactericidal activities. Plasma lysozyme, complement and total immunoglobulin values improved by 5 and/or 10 g OLE/kg supplementation. Before the ammonia exposure, the 5 and 10 g OLE/kg treatment significantly increased blood white blood cell, but there was no significant difference among the treatments after the ammonia exposure. Ammonia exposure significantly increased plasma malondialdehyde levels; however, 1 and 5 g OLE/kg treatments had significantly lower values compared to the other treatments. The present results suggest that 1 g OLE/kg diet may improve fish health and reduce the adverse effects of ammonia toxicity on common carp. 相似文献
107.
N.M. Hosseini J.A. Palta J.D. Berger K.H.M. Siddique 《Agricultural Water Management》2009,96(12):1732-1736
Soil water content at sowing is an important determinant of chickpea seed emergence and early growth. The seed emergence and seedling growth of 9 kabuli and 11 desi chickpea genotypes sown and grown under four soil moisture contents (25, 50, 75 and 100% of field capacity) was measured in a glasshouse study. Across soil moisture treatments the day of first emergence was negatively correlated to all plant growth parameters, e.g. above-ground biomass and plant height (r = −0.83 to −0.94). At 50 and 25% field capacity the onset of seed emergence was delayed, and both the number of seeds that emerged and early growth were reduced. Within the 25% soil moisture treatment, genotypes with an early emergence had a high rate of emergence (as estimated by regression against time) and produced seedlings with a high specific leaf area. Genotypic differences were observed in the number of seeds that emerged, day of first emergence, and early growth across the soil moisture treatments. Differences in final emergence were not related to chickpea type (i.e. desi or kabuli) or seed size, but the kabuli types emerged later than desi types (P < 0.001). The response of early dry matter production and leaf area to soil moisture was quadratically proportional to seed size, while the plant height response was linearly proportional to seed size. As a consequence kabuli chickpeas generated a higher degree of early vigour than desi types as soil moisture increased until seed sizes become extremely large, whereas under low soil moisture, kabuli chickpeas will have a much smaller or possibly no early vigour advantage over desi types. 相似文献
108.
Knowledge about heavy metal release from industrial solid wastes(ISWs) is crucial for better management of their environmental risks. This study was conducted to investigate the effect of organic and inorganic acids, clay minerals, and nanoparticles(NPs) on the release of heavy metals from sugar factory waste, ceramic factory waste, leather factory waste, and stone cutting waste. The influence of the extractants on heavy metal release from these ISWs was in the following descending order: citric acid oxalic acid nitric acid≥ sulfuric acid Ca Cl2. Addition of clay minerals and NPs as adsorbents decreased heavy metal release, which was significantly lower in NP-treated wastes than in the clay mineral-treated wastes. On the other hand, the presence of organic and inorganic acids increased heavy metal adsorption by NPs and clay minerals. These results suggest that NPs can be applied successfully in waste remediation,and organic and inorganic acids play an important role in the removal of heavy metals from the studied adsorbents. 相似文献
109.
Common carp juveniles were fed two types of diet (control: 0.1% tryptophan and TRP: 0.6% tryptophan) over 15 days. Thereafter, both groups were directly subjected to osmotic challenge (from 0 to 10 ppt) for 168 h. Blood samples were collected at ?240, 0, 6, 24, 72 and 168 h after challenge. Survival and serum cortisol, glucose, sodium and chloride levels were measured to determine stress response and osmoregulation condition. While TRP group showed no mortality until 168 h, cumulative mortality was near 100% at 72 h after challenge in control group. Feeding tryptophan-supplemented diet led to increase in prechallenge cortisol, but not glucose, sodium and chloride values at ?240 h that stayed elevated until 0 h after challenge. After challenge, cortisol and glucose values did not significantly affected by time of sampling but type of diet and diet × time interaction. Sodium values significantly affected by diet type and time of sampling but not their interaction. Chloride values significantly affected by time of sampling but not diet type and their interaction. Control group had higher cortisol, glucose and sodium than TRP at each time of sampling. Control and TRP group showed increasing and decreasing pattern in cortisol and glucose values when experiment progressed after osmotic challenge. Both group showed increasing pattern in sodium and chloride values when experiment progressed after osmotic challenge. Results indicated that tryptophan supplementation enhanced salt water tolerance of carp that is due to increase in basal cortisol and anti-stress effect of tryptophan and possibly increase in serotonergic activity. 相似文献
110.
The rate of phosporus (P) release from soils can significantly influence P fertility of soils. The objectives of this study were to investigate the effects of land‐use types on the kinetics of P release under different management practices and the relationship between kinetic parameters and soil physical and chemical properties from calcareous soils. The kinetics of P release in 0.01 M CaCl2 was studied in surface samples of 30 calcareous soils planted to garlic, garden, pasture, potato, vegetables, and wheat. Trend in P‐release kinetics was similar between land‐use types. Significantly different quantities of P were released under different land use. The maximum amount (average of five soils) (46.4 mg kg–1) of P was released in soil under potato and the minimum amount (10.4 mg kg–1) under pasture. The kinetics of P release from soils can be described as an initial rapid rate followed by a slower rate. Different models were used to describe P release. In general, parabolic diffusion and power equation were found to be appropriate for modeling P release. The P‐release rate for the soils was estimated by parabolic equation for the studied land‐use types. The constant b was lower for pasture and wheat than for garlic and potato. The relationship between the rate of P release with Olsen‐P was linear, while it was curved with respect to the CaCl2‐P, indicating that release of P was diffusion‐controlled. When the kinetic parameters of models were regressed on soil properties, CaCl2‐P and CaCO3 appeared to be the most important soil properties influencing P‐release rates in these soils. 相似文献