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11.
日龄、性别、蛋白质沉积和日粮赖氨酸效率对快速生长肉鸡的赖氨酸需求的影响 总被引：1，自引：0，他引：1
通过氮平衡试验,可以根据粗蛋白质(Crude Protein,CP)沉积量和日粮赖氨酸利用率,评估不同性别和日龄的快速生长型肉鸡(科宝500)的赖氨酸需要量.试验分为3个日龄段(第1日龄段10～25日龄,第2日龄段30～45日龄;第3日龄段50～65日龄),每个日龄段各72羽试验鸡(公母各36羽).试验日粮由高蛋白质(High Protein,HP)-豆粕、小麦蛋白质和结晶氨基酸(L-苏氨酸(Thr)、DL-蛋氨酸(Met)、L-精氨酸(Arg)]组成,共设6个级别的粗蛋白质水平,从而使得赖氨酸(4.30gLys/100gCP)成为日粮的第一限制性氨基酸[Lys:(Met Cys):Thr:Arg=1:1.01:0.91:1.14].由于应用了非线性氮利用率模型,将氮维持需要量(Nitrogen Maintenance Requirement,NMR)和每日氮日沉积的理论最大值(Theoretical Maximum for day Nitrogen Retention,NRmax T)确定为模型参数,以便能进一步评估依赖于日龄、性别和每日粗蛋白质沉积量的赖氨酸需要量.例如,按每日粗蛋白质沉积量理论潜能的60%计算得到的日粮赖氨酸需求水平(10～25日龄:赖氨酸含量1.10%,日采食量60g;30～45日龄:赖氨酸含量1.03%,日采食量140 g;50～65日龄:赖氨酸含量0.96%,日采食量170g)与已报道的结果完全一致.然而,当氨基酸需要量水平确定后,采食量预测值就成为最重要的影响因子之一.而作为影响氨基酸需要量重要因素的每日粗蛋白质沉积量和日粮氨基酸的利用效率,在今后的氨基酸需要量研究中还需作进一步的研究. 相似文献
12.
Mohammad Farkhari Alan Krivanek Yunbi Xu Tingzhao Rong Mohammad R. Naghavi Bahman Y. Samadi Yanli Lu 《Plant Breeding》2013,132(1):90-98
Large‐scale selective genotyping and high‐throughput analysis are two important strategies for low‐cost and high‐effective genetic mapping. In this study, selective genotyping was applied to four maize F2 populations. Thirty plants were selected from each of the two tails of the original F2 populations to represent extreme resistant and susceptible plants to root lodging, and genotyped individually with 1536 single nucleotide polymorphisms (SNPs). A quantitative trait locus (QTL) was declared when at least three closely linked SNPs showed significant allele frequency difference between the two tails. Nine QTL were identified for root lodging across the four populations, which were located on chromosomes 2, 4, 5, 7, 8 and 10 and one of them was shared between two populations. A total of 20 segregation distortion regions (SDRs) were identified across the four populations, one of which was co‐localized with a QTL on chromosome 4. The tightly linked SNPs identified in this study can be used for marker‐assisted selection for root lodging. Selective genotyping, when combined with pooled DNA analysis, can be used to develop strategies for high‐throughput genetic mapping for all crops. 相似文献
13.
The goal of this study was the evaluation of specific markers of myocardial injury that includes CK-MB and troponin I in major thalassemic patients. Regular blood transfusion is the main treatment in major thalassemia. One of the most important complications of regular blood transfusion is iron overload that eventually involves many organs like heart and cause myocardial injury. Sixty patients with transfusion-dependent major thalassemia, at the age range of 8 to 15 years in Tabriz Pediatric Medical Center were chosen. Measurement of Hb, Hct and serum ferritin were performed in hospital laboratory, but total serum Creatine Kinase (CK) by photometric and isoenzyme of CK-MB by immunologic DGKC and cardiac troponin I (cTnI) were tested by ELISA methods in Shaheed Madani heart center laboratory before blood transfusion. For all patients echocardiography and ECG assessment of cardiac function were done by a pediatric cardiologist and results were statistically analyzed. Forty nine patients (group A) had normal left ventricular ejection fraction (LVEF = 50-70%) and 11 patients (group B) had reduced LVEF (20-45%). There was no statistical difference between two groups in average volume of blood transfusion (p = 0.074). Although total CK and CK-MB isoenzyme were higher in group B but there was no statistically meaningful difference between two groups (p = 0.123, p = 0.111). Troponin I also was higher in group B but statistically analysis showed no correlation between cardiac function and troponin I level in these groups (p = 0.827). This study showed that cardiac markers are not helpful for recognition of cardiac involvement in major thalassemia. 相似文献
14.
We studied the effect of wollastonite nanofibers on fluid flow in medium-density fiberboard(MDF).Nanowollastonite(NW) was applied in MDF at 10 %,based on the dry weight of wood fibers. We also tested chicken feathers as an additive to the matrix at 5 and 10 %by weight. The weight of feathers was reduced from the wood fibers to keep the density of the panels constant(0.66 g cm-3). Wollastonite nanofibers acted as filler in the matrix and significantly decreased gas and liquid permeability. Higher thermal conductivity of the NW-treated MDF-mats resulted in a better cure of resin, and consequently more integrity in the composite-matrix and lower permeability. The water-repellant property of wollastonite also contributed to the decrease in liquid permeability.Feathers reduced gas and liquid permeability due to the hydrophobic nature of keratin, as well as its formation as a physical barrier towards passing of fluids. Ten percent feather content proved too high and some checks and cracks occurred in the core of the panels after hot-pressing.Panels with 5 %-feather content resulted in both lower fluid flow and adequate physical integrity in the core section of the MDF-matrix. 相似文献
15.
Salar Rezapour A. A. Jafarzadeh Abbas Samadi Sh. Oustan 《Archives of Agronomy and Soil Science》2013,59(2):165-182
The iron oxides fractions of four major physiographic units obtained from a transect of calcareous materials were studied to assess the effects of key pedogenic processes and local hydrology conditions as well as physiographic units in controlling iron oxides forms in the north-west of Iran. Samples from different horizons belonging to six pedons were selected and analyzed for soil physicochemical properties, clay minerals, and Fe oxides forms (Fed, Feo, Fep). In general, the soils indicated some variation in the concentration of iron oxides that could be related to rate of weathering, pedogenic accumulations, geomorphologic conditions (as results of different in physiographic units), wet and dry cycle, and organic matter. A wide relative variation in mean values of Fed (6.4–9.9 g kg?1), Feo (2.9–4 g kg?1), and Fep (0.68–1.3 g kg?1) was observed among physiographic units. On the plateau unit, the presence of the most stable geomorphologic conditions and high rate in situ weathering (reflected in clay content), coupled with minor deposition of sediment suggest that the soils have more dynamic conditions than other units, reflecting in the greatest amount Fed and the lowest Feo/Fed ratio. Fed content of the soils containing less clay content (15–25%) was significantly different from those with greater clay content (25–35%). 相似文献
16.
Esmaeilzade B Nobakht M Joghataei MT Rahbar Roshandel N Rasouli H Samadi Kuchaksaraei A Hosseini SM Najafzade N Asalgoo S Hejazian LB Moghani Ghoroghi F 《Iranian Biomedical Journal》2012,16(1):1-9
Background: Alzheimer’s disease (AD) is characterized by progressive neuronal loss in hippocamp. Epidermal neural crest stem cells (EPI-NCSC) can differentiate into neurons, astrocytes and oligodendrocytes. The purpose of this study was to evaluate the effects of transplanting EPI-NCSC into AD rat model. Methods: Two weeks after induction of AD by injection of Amyloid-β 1-40 into CA1 area of rat hippocamp, Y-maze and single-trial passive avoidance tests were used to show deficit of learning and memory abilities. EPI-NCSC were obtained from the vibrissa hair follicle of rat, cultured and labeled with bromodeoxyuridine. When Alzheimer was proved by behavioral tests, EPI-NCSC was transplanted into CA3 area of hippocamp in AD rat model. The staining of EPI-NCSC markers (nestin and SOX10) was done in vitro. Double-labeling immunofluorescence was performed to study survival and differentiation of the grafted cells. Results: We showed that transplanted EPI-NCSC survive and produce many neurons and a few glial cells, presenting glial fibrillary acidic protein. Total number of granule cells in hippocamp was estimated to be more in the AD rat model with transplanted cells as compared to AD control group. We observed that rats with hippocampal damage made more errors than control rats on the Y-maze, when reward locations were reversed. Conclusion: Transplanted cells were migrated to all areas of hippocamp and the total number of granule cell in treatment group was equal compared to control group. Transplantation of EPI-NCSC into hippocamp might differentiate into cholinergic neurons and could cure impairment of memory in AD rat model.Key Words: Alzheimer’s disease, Cholinergic neuron, Hair follicle 相似文献
17.
As a prerequisite to improving diseaseresistance and grain quality in Iranianrice cultivars, we determined the geneticrelatedness of popular local cultivars andblast-resistance donor germplasm usingfingerprints derived from simple sequencerepeat (SSR) and plant defense genemarkers. Fifty SSR markers and 28 defensecandidate genes were used to assess thegenetic diversity among popular ricecultivars from Iran and donors of blastresistance from breeding programs in Asia.Gene diversity estimate of the 16 corebreeding lines was 0.440 ± 0.028 basedon SSR markers. Genetic relationships amongthe cultivars were determined by clusteranalysis using SSR and candidate genedatasets. DNA fingerprints derived fromSSR and defense gene markers gave similargroupings of cultivars consistent withtheir genetic background: a) Iranian localvarieties, b) improved varieties in Iranplus donor indica germplasm from Asia, andc) japonica germplasm. Within-groupsimilarities for the traditional andimproved cultivars were greater than 80%and 75%, respectively. The traditional andimproved cultivars showed differentialreaction to blast pathogen isolates; alltraditional varieties were susceptible toblast pathogen isolates in Iran butresistant to isolates in the Philippines,whereas the improved varieties showedopposite reaction to pathogen isolates inIran and the Philippines. Both molecularand phenotypic data suggest a narrowgenetic basis in local and improvedcultivars in Iran and the need forincluding more diversity for the breedingprogram. The high degree of polymorphismobserved between local cultivars and donorsof blast resistance provide the neededinformation to follow the transmission ofresistance alleles from the donors inadvancing breeding lines. 相似文献