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91.
92.
A total of 250 one-day-old Ross 308 male chicks were used to investigate the effects of Fe-methionine (Fe-met) and iron sulfate (FeSO4.7H2O) on performance, mineral concentration, meat quality, and oxidative stability of breast. The feeding experiment was performed with five dietary groups including group I (basal diet [BD] + 80 mg/kg FeSO4), group II (BD + 60 mg/kg FeSO4 + 20 mg/kg Fe-met), group III (BD + 40 mg/kg FeSO4 + 40 mg/kg Fe-met), group IV (BD + 20 mg/kg FeSO4 + 60 mg/kg Fe-met), and group V (BD + 80 mg/kg Fe-met). The results showed that Fe and Cu content in the breast muscle increased by dietary supplementation of organic and inorganic iron from II to V groups. Dietary groups of II, IV, and V increased L* value and b* value of breast meat. Additionally, redness of breast meat enhanced linearly and quadratically by dietary supplementation of 80 mg/kg Fe as FeSO4. In addition, dietary supplementation Fe from II to V groups led to a significant increase in pHu at 24-h postmortem while it was negatively correlated with L* value of breast muscle. This study demonstrates that replacing FeSO4 with Fe-Met could improve breast meat yield of broilers. Although 80 mg of Fe-Met improved the iron content of meat, it showed detrimental effects on the lipid oxidation of breast meat.  相似文献   
93.
Variation of high molecular weight gluteninsubunits (HMW-GS) at the Glu-1 lociwas studied using SDS-PAGE method in 43advanced lines or cultivars commonly grownin Iran. Fourteen alleles and 21 alleliccompositions were detected. Among the 43bread wheats analysed only five showed aunique HMW-GS composition. The mostfrequent HMW-GS patterns were 2*, 7+8,2+12 and 2*, 17+18, 2+12 which wereobserved in 13 and six cultivars,respectively. In the remainings, each twoto three lines or cultivars showed a commonHMW-GS pattern. Therefore, allelicvariation at Glu-1 loci is of limitedvalue for cultivar identification comparedwith loci controlling gliadins. Sevencultivars were observed to consist of twoto three biotypes with different alleles.In cultivar Mahdavi a biotype showedinactivity at the Glu-B1 locus. Analready reported rare subunit pair'2***+12' at Glu-D1locus was found in cultivar Kavir. Theresults of scoring cultivars for theirquality based on the HMW-GS compositionswith an average score of eight, wasgenerally good. Cultivars Inia, Tajan, andadvanced lines N-75-11 and N-75-15 showedquality score equal to 10, whereas Alamootand C-75-5 showed quality scores equal tofive. The quality of former and latterlines and cultivars were considered highestand lowest, respectively. The resultsobtained in this study are useful inbreeding programs to improve bread makingquality, developing uniformity andimproving heterogeneous cultivars by meansof selection of the best genotypes.  相似文献   
94.
The present study was carried out to explore the impacts of dietary supplementation of enzyme mixture with sodium butyrate on the growth performance, carcass traits, blood profile and economic benefit in two breeds of weanling rabbits adapted to survive in Egypt (New Zealand White and Rex). One-hundred and twenty weaned male rabbits (New Zealand White and Rex) of 6 weeks of age and 770.5 ± 20 g body weight were allotted randomly into four groups in a factorial arrangement. The obtained results indicated that there were non-significant differences in all growth performance traits, blood profile and economic parameters due to the breed effect. However, there were significant differences in most of carcass traits due to the breed effect except total giblets and New Zealand White breed showed the highest value of these parameters including dressing % (p < .01), forequarter and loin % (p < .001) and hindquarter % (p < .003) compared with Rex breed counterparts. The effect of the treatment and its interaction with the breed significantly (p < .05) improved body weight gain, feed consumption and carcass traits (percentage of dressing, forequarter, hind quarter and lion). However, final body weight and feed conversion ratio were not significantly influenced. Supplementing a diet with treatment significantly decreased blood triglycerides, cholesterol and the ratio between albumin and globulin (A/G ratio), while increased blood total protein and globulin. Although higher feed cost and total costs in treated groups than control ones in each breed, they showed higher total return and net return. Rex non-treated rabbit breed showed the lowest profitability measures compared with other groups. In conclusion, dietary supplementation of multi-enzyme with sodium butyrate is highly recommended in growing rabbits due to their beneficial effects on the growth performance and profitability.  相似文献   
95.
Salinity adversely affects plant growth, photosynthesis, and availability of nutrients including iron. Rice (Oryza sativa L.) is susceptible to soil salinity and highly prone to iron (Fe) deficiency due to lower release of Fe‐chelating compounds under saline conditions. In order to investigate the effects of salinity and low iron supply on growth, photosynthesis, and ionic composition of five rice genotypes (KS‐282, Basmati Pak, Shaheen Basmati, KSK‐434 and 99417), a solution culture experiment was conducted with four treatments (control, 50 mM NaCl, Fe‐deficient, and 50 mM NaCl + Fe‐deficient). Salinity and Fe deficiency reduced shoot and root growth, photosynthetic and transpiration rates, chlorophyll concentration, and stomatal conductance. The reduction in all these parameters was more in the interactive treatment of salinity and low Fe supply. Moreover, a significant increase in shoot and root Na+ with corresponding decrease in K+ and Fe concentrations was also observed in the combined salinity and Fe‐deficiency treatment. Among the tested genotypes, Basmati Pak was the most sensitive genotype both under salt stress and Fe deficiency. The genotype KS‐282 performed better than other genotypes under salinity stress alone, whereas Shaheen Basmati was the best genotype under Fe deficiency in terms of all the studied parameters.  相似文献   
96.
In order to investigate the effect of anesthesia on serum parameters, Beluga, Huso huso (L.) were blood-sampled immediately without anesthesia (control) or subjected to following anesthesia procedure: 40, 120, and 240 s exposure to 3,000, 700, and 500 mg l−1 clove solution, respectively. Blood samples were collected after these periods, when fish were immobile and reached stage 4 anesthesia. Results showed that cortisol and glucose levels were significantly high in 700 and 500 but not 3,000 mg l−1 group compared to control. Serum lactate levels were significantly high in 500 mg l−1 group compared to control group. Lactate levels were not significantly differed between control, 3,000, and 700 mg l−1 groups. There were no significant differences in serum levels of cholesterol, total protein, lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, Na+, Cl, K+, and Ca2+. Results suggest that rapid anesthesia with higher dose is better than slow anesthesia with lower dose for blood sampling in Beluga.  相似文献   
97.
Subclinical ketosis (SCK) is simply a condition marked by increased levels of circulating ketone bodies without the presence of the clinical signs of ketosis. Subclinical ketosis can cause economic losses through decreased milk production and association with preparturient diseases. Limited information is available regarding the prevalence of SCK in dairy herds in Southwestern Iran. The objectives of this study were (i) determination of the cutoff point of nonesterified fatty acids (NEFAs) and glucose concentrations for diagnosis of SCK using receiver operating characteristic (ROC) analysis, and (ii) determination of prevalence of subclinical ketosis in apparently healthy dairy cattle in Southwestern Iran. From October to December 2009, a total of 100 clinically healthy multiparous Holstein cows (3-8 years old) were randomly selected from 16 dairy herds around Kazerun, Fars Province, Iran. The cows had two-six lactations, with body weight ranging from 500 to 650 kg. Blood samples for each cow were taken at 2, 4 and 6 weeks post parturition and 3-4h after the morning feeding. The optimal cutoff point was set, by the ROC method, to >0.26 mmol/L for NEFA, and < 2.26 mmol/L for glucose with corresponding 82.54% sensitivity and 91.89% specificity for NEFA and 44.44% sensitivity and 78.38% specificity for glucose. Cows with BHB concentrations higher than 1200 μmol/L were classified as having SCK. In 2, 4 and 6 weeks post parturition 63%, 68% and 59% of the tested cows were subclinically ketotic. Overall, 97% of tested cows (97/100) were considered subclinically ketotic in at least one sample period. Thirty percent of tested cows (30/100) suffered from subclinical ketosis in all of the 2, 4 and 6 weeks postpartum. The results suggest that, a cut-off point of 0.26 mmol/L for NEFA concentrations can be used during early lactation for diagnosis of subclinical ketosis and making management decisions for prevention and treatment. Glucose cannot be a good criterion for diagnosis of SCK and it does not appear to be useful for monitoring subclinical ketosis.  相似文献   
98.
Results of indirect fluorescent-antibody microscopy did not differ significantly from complement-fixation test results in diagnosing paratuberculosis (Johne's disease) in cattle. Neither test had acceptable sensitivity or specificity for detecting subclinical cases.  相似文献   
99.
为了提高所选定飞行器模型的机动性,采用了一种标准遗传算法设计前缘翼根延伸(LEX).同时使用一种由三维低阶板方法结合DATCOM方法半经验公式的改进方法预测复杂外形飞行器(机身 机翼 尾翼)的空气动力载荷和最大升力系数.结果表明,在前缘翼根存在的情况下,升力系数在马赫数为0.4~0.8时提升了20.5%~15.3%,在马赫数为1.2时提升了6.8%,在马赫数为0.2~0.95之间升力系数最大值提升了9.5%~15%.在1~5 km的高度亚音速飞行时,其回转率得到了6.6%~8.0%的提升.  相似文献   
100.
We carried out a study to see the effect of contaminated water of Nullah Dek on fine rice paddy and straw yields and trace elements accumulation in different parts of rice plants and soil. A site was selected near the bank of Nullah Dek at Kot Pindi Das in the District of Sheikhupura, Pakistan. The water of this nullah is contaminated by industrial effluents carrying different micronutrients. This water was employed to grow rice crop. Water samples were collected before transplanting and during the season with 15 days interval for analysis from 20 July to 1 November 2002 from a spot near village Shamke. Three fine rice varieties, viz. Super Basmati, Shaheen Basmati and Basmati 2000 were transplanted. These rice varieties were grown up to maturity. Paddy and straw yields data were recorded. Six composite soil samples from three random spots were collected from the experimental site before the start of the study to see the status of trace elements in soil. After the harvest of rice crop, soil, paddy and straw samples were analysed for Zn, Cu, Fe and Mn. The chemical analysis of Nullah Dek water showed that total salts concentration was greater than the safe limit, i.e. electric conductance (EC) > 1.0 dS m−1. Even sodium adsorption ratio (SAR) was very high, but there was no problem of high residual sodium carbonate (RSC). Zn, Cu, Fe and Mn were present but within safe limits. The water of Nullah Dek remained within permissible limits of irrigation from onset of rainy season till 15 October. There was an increase in EC, SAR and trace elements concentrations after 15 October but within safe limits. Soil analysis revealed its saline nature, devoid of sodicity. Among trace elements, the zinc ranged between deficiency (<0.5 mg kg−1) and adequate limits (>1.0 mg kg−1). Copper, Mn and Fe were present in adequate amounts. After the harvest of rice crop there was a slight decrease in pH, ECe and SAR at both the depths, while the concentrations of all trace elements were slightly increased with more in upper layer than the lower layer. Shaheen Basmati produced the maximum paddy yield followed by Basmati 2000 and then Super Basmati. The chemical analysis of paddy samples indicated a sufficient accumulation of zinc (1.68–1.78 mg kg−1), copper (1.38–1.45 mg kg−1), iron (6.12–6.37 mg kg−1) and manganese (2.22–2.42 mg kg−1). Analysis of rice straw also showed sufficient accumulation of zinc (27.50–28.50 mg kg−1), copper (20.0–20.50 mg kg−1), iron (270–280 mg kg−1) and manganese (2.38–2.41 mg kg−1).  相似文献   
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