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1.
High levels of guanidinoacetate acid (GAA) deteriorate growth response in broiler chickens. We propose using coenzyme Q10, an antioxidant, and taurine (TAU), a methyl donor, to cope with the situation when high level of GAA included in diet. GAA was supplemented at 0 (control), 0.75, 1.5 and 2.25 g/kg in isoenergetic and isonitrogenous diets and fed to broilers (Cobb 500) from 1 to 40 days post‐hatch. Three additional diets were prepared by adding CoQ10 (40 mg/kg), TAU (40 mg/kg) or their combination (both CoQ10 and TAU at 40 mg/kg) to the 2.25 g/kg GAA group. The experimental design used was a completely randomized design. While weight gain (p = 0.038) and feed conversion ratio (p = 0.024) improved when GAA added at 1.5 g/kg, higher supplementation (2.25 g/kg) deteriorated these responses. These responses, however, were significantly restored by using CoQ10, TAU or their combination. Abdominal fat deposition was significantly decreased when TAU added to broiler diets by virtue of upregulating peroxisome proliferator‐activated receptor alpha. Supplementing broiler diets with CoQ10 and TAU or their combination significantly decrease ascites mortality. In conclusion, CoQ10 and TAU have shown beneficial effects when high level of GAA included in broiler diets.  相似文献   
2.
Forty landraces of Damask rose were collected from 28 provinces (13 origin sites) in Iran and evaluated to determine the diversity among them. The investigated characters were: flower weight, flower diameter, peduncle length, number of petals, number of stamens and oil content. Pearson's coefficients showed that number of petals was positively correlated with flower weight (r = 0.642) and number of stamens (r = 0.630), while its correlation with peduncle length was negative (r = −0.53). A negative correlation was obtained between oil content and number of stamens (r = −0.60) which is useful for indirect selection of landraces with low number of stamens and therefore high amount of oil content. Cluster analysis based on five botanical characters and oil content separated the origin site 12, which included Guilan, Mazandaran and Golestan provinces with a specific climate condition of temperate humid, from other origin sites. This distinctiveness was already confirmed by the bi-plot of the principal components. The distribution of Damask rose landraces provided useful information for the future collection and for the genetic resource management in these origin sites.  相似文献   
3.
The aim of this study was to investigate the cytotoxic and anticancer activities of stylosin, a monoterpene extracted from an edible plant, Ferula ovina, on 5637 and HFF3 cells using MTT and comet assays and DAPI staining.To assess stylosin effects, cells were cultured in the presence of various concentrations of stylosin during three days; the IC50 of stylosin on cancerous 5637 cells was less than its value on HFF3 normal cells, indicating that it might have anticancer properties. Investigating the mechanism of stylosin action revealed that it quickly induced DNA lesions and increased the number of apoptotic cells.  相似文献   
4.
A new analytical method (liquid chromatography-antioxidant, LC-AOx) was used that is intended to separate beer polyphenols and to determine the potential antioxidant activity of these constituents after they were allowed to react online with a buffered solution of the radical cation 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(?+)). Using the LC-AOx method, it was possible to demonstrate that the extent of the antioxidant activity was very much dependent on the phenolic compound considered. The method was also applied to the analysis of beer extracts and allowed the evaluation of their antioxidant activity at different steps of beer processing: brewing, boiling, and fermentation. This study showed that the total antioxidant activity remained unchanged throughout beer processing, as opposed to the polyphenolic content, which showed a 3-fold increase. Hopping and fermentation steps were the main causes of this increase. However, the increase measured after fermentation was attributed to a better extraction of polyphenols due to the presence of ethanol, rather than to a real increase in their content. Moreover, this method allowed the detection of three unknown antioxidant compounds, which accounted for 64 ± 4% of the total antioxidant activity of beer and were individually more efficient than caffeic acid and epicatechin.  相似文献   
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6.
The objective of this study was to evaluate if treatment of equine chorionic gonadotrophin (eCG)-superovulated Sanjabi ewes with repeated administration of human chorionic gonadotropin (hCG) would increase the number of normal corpus luteum (CL) and serum progesterone concentrations and decrease the number of persistent follicles. The superovulated ewes were divided into four groups on day 0 (day of sponge removal); the ewes were treated by an intramuscular administration of 500?IU hCG on day 0 (Group I: n?=?10), on days 0 and 1 (Group II: n?=?10), or on days 0, 1, and 2 (Group III: n?=?10) and no treatment for control group (n?=?10). Blood samples were collected on days 0, 1, 2, 5, and 8 (day of slaughter), and serum progesterone concentrations were determined. According to progesterone concentrations, 50 (4/8) and 0?% of the ewes underwent premature luteal regression in the control group and the hCG groups, respectively. There were more CLs in Group III than in Group II and the control group. Ewes treated with hCG had a greater number of normal-looking CL. CL diameter was significantly greater in Group II and Group III than other groups. Total CL weight was significantly (P?<?0.05) higher in Group III than in Group I and the control group. Number of persistent follicle and persistent follicle diameter were lower in control group compared to the other groups. Eight days after sponge removal, serum progesterone concentration was significantly higher in Group III than in Group I and the control group. The present results indicate that repeated administration of hCG supported CL formation, increased serum progesterone concentration, and prevented premature luteal regression in eCG-superovulated Sanjabi ewes.  相似文献   
7.
Pomegranate is one of the native fruits of Iran which contains high genetic resources, but there are insufficient information regarding properties of the fruit. The objective of the present study was to investigate the physcio-chemical characteristics and antioxidant activity of twenty pomegranate cultivars grown in Iran. This study showed that there were significant differences among the cultivars in all measured factors except the length/diameter ratio of fruit. The fruit weight, skin percentage, aril percentage and juice percentage were within the range of 196.89–315.28 g, 32.28–59.82%, 37.59–65% and 26.95–46.55%, respectively. The total soluble solids content varied from 11.37 (°Brix) to 15.07 (°Brix), pH values from 3.16 to 4.09, titratable acidity content from 0.33 g 100 g−1 to 2.44 g 100 g−1 and total sugars content from 13.23 g 100 g−1 to 21.72 g 100 g−1. The results also showed that the values of ascorbic acid ranged from 9.91 mg 100 g−1 to 20.92 mg 100 g−1. The total anthocyanins content was observed in pomegranate cultivars between 5.56  mg 100 g−1 and 30.11 mg 100 g−1. The level of total phenolics was varied from 295.79 mg 100 g−1 to 985.37 mg 100 g−1. The antioxidant activity of pomegranate cultivars was found between 15.59 and 40.72%. These data demonstrated that the cultivar was the main parameter which influences the physico-chemical properties and antioxidant activity in pomegranates.  相似文献   
8.
Twenty-four Holstein dairy cows were used to evaluate the singular and combined effects of different level of crude protein and monensin treatments during the early lactation on digestion and milk yield of dairy cows. The experiment was designed as completely randomized with a 3x2 factorial arrangement of treatments. The factors were three Concentrations of CP supplement (19.5, 21.4 and 23.4% of dry matter) and two levels of monensin (0 and 350 mg per cow per day). This experiment consist of three periods and each period was 3 week in length. Monensin did not affect DMI, milk yield, lactose and SNF but it reduced milk fat and protein percentage. Monensin premix significantly decreased rumen ammonia but rumen pH and microbial protein synthesis was not affected by monensin treatment. Although, Monensin treatment increased apparent digestibility of DM, NDF, ADF, CP, but they were not significantly. Increasing dietary CP, improved milk and protein production, but did not alter the other components of milk. Digestibility of NDF, ADF, CP were improved by increasing dietary CP. Increasing diet CP from 19.5 to 21.4% did not significantly increase ruminal ammonia, but increasing to 23.4% have significant effect on it. There was a linear relationship between level of crud protein in the diet and urine volume excretion. Microbial protein synthesis was affected by increasing CP level; on this way maximum protein synthesis was achieved in 21.4% CP.  相似文献   
9.
To investigate the effects of niacin supplementation in the diet of high producing cows at early lactation, 21 holstein dairy cows were used in this experiment. Animal were assigned in to three groups based on their milk yield and calving date soon after parturition. They were received a basal diet and 0 (group 1), 6 (group 2), 12 (group 3) g of supplementation niacin per day over a 10 weeks experimental period. Milk volume was recorded and milk samples were collected for each cow at two weeks interval for analysis of fat, protein, lactose and SNF (Solid-None Fat). Blood samples were also taken for the measurement of glucose, triglyceride, Beta-hydroxy butyrate and total protein at two weeks intervals. No significant difference were observed between milk yield, milk fat, protein, lactose and SNF content in cows received niacin compared to the control group (p > 0.05). Plasma glucose in groups 2 and 3 compared to the control were higher and this difference were statistically significant (p < 0.05). Blood triglycerides were not significantly affected by niacin supplementation. BHBA were lower in cows received niacin and this difference were significant (p < 0.05). The trend of changes in the amount of blood total protein were identical in all three groups whole the level of this factor was always higher in control group compared to the others groups. Niacin has showed an increase in the level of plasma glucose and a notable decrease in the amount of blood triglyceride, beta-hydroxy butyrate and total protein, which may be due to the effect of this vitamin on the energy metabolism in cows.  相似文献   
10.
This study was aimed to investigate dual effects of irrigation regimes and N fertilizer rates on some agronomic traits (with emphasis on yield qualitative and quantitative characteristics) and finding optimized irrigation level and N application rate for two canola (Brassic napus L.) cultivars. For this purpose, two variety of canola (Zarfam and Modena), four irrigation regimes including 30%, 45%, 60% and 75% (I1-I4) of maximum allowable depletion (MAD) of available soil water (ASW) and four nitrogen rates (viz. 0, 90, 180 and 270 kg N ha−1 (N1-N4) were involved in Karaj, Iran for two successive years (2007-2008). Our results revealed special fertilizer threshold for each irrigation regime in respect to seed yield. Response rate to fertilizers was ceased in lower fertilizer rates by prolonging irrigation. The response rate showed a decrease of 15.4%, 17.2% and 30.7% in I2, I3 and I4 in comparison with I1, but I2 response to fertilizer ceased in higher N rate as Ncritical (189.8 kg N ha−1). This implies that I2 improved response of canola cultivars to N fertilizer, which was accompanied by its higher WUE. Also, all estimated Ncriticals for all irrigation levels were higher than the current recommendation of 130 kg N ha−1. This show the capability of increasing canola cultivars yield in study region by reasonable increasing of fertilizer rate (decreasing gap between recommended N rate and estimated values) in advisable irrigation regime (I2). Cultivars tended to respond similarly to irrigation and nitrogen for seed yield in both years, but Zarfam was more efficient than Modena in respect to response to diverse treatments.  相似文献   
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