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121.
Wheat cultivars possessing quality attributes needed to produce optimum quality tortillas have not been identified. This study investigated the effect of variations in high‐molecular‐weight glutenin subunits encoded at the Glu‐1 loci (Glu‐A1, Glu‐B1, and Glu‐D1) on dough properties and tortilla quality. Flour protein profiles, dough texture, and tortilla physical quality attributes were evaluated. Deletion at Glu‐D1 resulted in reduced insoluble polymeric protein content of flour, reduced dough compression force, and large dough extensibility. These properties produced very large tortillas (181 mm diameter) compared with a control made with commercial tortilla wheat flour (161 mm). Presence of a 7 + 9 allelic pair at Glu‐B1 increased dough strength (largest compression force, reduced extensibility, and small‐diameter tortillas). Deletion at Glu‐A1 produced large tortillas (173 mm) but with unacceptable flexibility during storage (score <3.0 at day 16). In general, presence of 2* at Glu‐A1, in combination with 5 + 10 at Glu‐D1, produced small‐diameter tortillas that required large force to rupture (tough texture). Presence of 2 + 12 alleles instead of 5 + 10 at Glu‐D1 produced tortillas with a good compromise between diameter (>165 mm) and flexibility during storage (>3.0 at day 16). These allele combinations, along with deletion at Glu‐D1, show promise for tortilla wheat development.  相似文献   
122.
Limited information is available on biological effects of various levels of nickel (Ni) (deficiency to toxicity levels) on growth and yield of certain crops, particularly vegetables. In this sand‐culture study, we investigated the effects of four levels of Ni (0, 50, 100, and 200 μM) on growth, yield, and fruit‐quality attributes of two cucumber cultivars (Cucumis sativus L. cvs. Super Dominus and Negin) supplied with urea or NH4NO3 as nitrogen source. Addition of 50 μM Ni to the nutrient solution resulted in a significant increase of shoot and root dry‐matter yield of cv. Negin although this increase was greater in the urea‐fed plants than those fed with NH4NO3. In both cultivars, addition of 50 μM Ni increased urease activity and thereby decreased the urea concentration in the urea treatment. Addition of 100 and 200 μM Ni caused a significant decrease in root and shoot growth of cucumber although this decrease was insignificant for cv. Super Dominus in the 100 μM treatment. The highest fruit yield, total soluble solids (TSS), and fruit firmness were achieved at the 50 μM Ni treatment. Regardless of nitrogen source, Ni addition proportional to the concentration used increased leaf Ni concentration and fruit acid ascorbic concentration. The concentration of Ni required for optimum growth and yield of cucumber varied with cultivars. The level of 50 μM was sufficient for optimum growth of cv. Negin in nutrient‐solution culture while lower concentration of Ni was required for cv. Super Dominus. While the beneficial effects of sufficient levels of Ni on growth and yield of urea‐fed plants was greater than with NH4NO3‐fed plants, the toxic effects of Ni in these plants were also greater.  相似文献   
123.
Final observations on experimental transmission of chronic wasting disease (CWD) from elk (Cervus elaphus nelsoni) and white-tailed deer (Odocoileus virginianus) to fallow deer (Dama dama) are reported herein. During the 5-year study, 13 fawns were inoculated intracerebrally with CWD-infected brain material from white-tailed deer (n = 7; Group A) or elk (n = 6; Group B), and 3 other fawns were kept as uninoculated controls (Group C). As described previously, 3 CWD-inoculated deer were euthanized at 7.6 mo post-inoculation (MPI). None revealed presence of abnormal prion protein (PrP(d)) in their tissues. At 24 (Group A) and 26 (Group B) MPI, 2 deer were necropsied. Both animals had a small focal accumulation of PrP(d) in their midbrains. Between 29 and 37 MPI, 3 other deer (all from Group A) were euthanized. The 5 remaining deer became sick and were euthanized between 51 and 60 MPI (1 from Group A and 4 from Group B). Microscopic lesions of spongiform encephalopathy (SE) were observed in only these 5 animals; however, PrP(d) was detected in tissues of the central nervous system by immunohistochemistry, Western blot, and by commercial rapid test in all animals that survived beyond 24 MPI. This study demonstrates that intracerebrally inoculated fallow deer not only amplify CWD prions, but also develop lesions of spongiform encephalopathy.  相似文献   
124.
Three Japanese Black cows housed with 6 other cows exhibited main clinical symptoms of severe hemoglobinuria. Hematological analyses conducted after antibiotic therapy demonstrated severe anemia, and biochemical analyses indicated both severe hemolysis and disruption of hepatic function. One of the three cows died. Based on the above analyses and observation of typical clinical symptoms, a speculative diagnosis of bacillary hemoglobinuria was made, and immediate high-dose antibiotic treatment improved the general conditions of the surviving animals. Blood samples from the other 2 cows were collected sequentially after antibacterial therapy. Clostridium haemolyticum was detected by a nested polymerase chain reaction analysis of the blood samples. The cows were diagnosed with the second recorded occurrence of bacillary hemoglobinuria in Japan.  相似文献   
125.
Artemisinin has been used for centuries to treat malaria, intestinal tract helminthosis, diarrhea, and used as an antipyretic and sedative agent, but the usage in veterinary medicine is a new field. Recently, it has been used successfully to control experimental poultry coccidiosis. The present study aimed to determine the effects of different doses of artemisinin in broiler chickens with chronic usage. Sixty birds divided into one control and four treatment groups that fed rations mixed with artemisinin at doses of 17, 34, 68, and 136 ppm for 36 days. During the experiment, birds showed no clinical signs except anemia. In microscopic examinations, heart, lung, and spleen had no lesion, but liver, kidney, and brain showed various lesions. Degenerative lesions like intracytoplasmic eosinophilic inclusions were seen in both kidney and liver but fatty change was seen only in liver. There was no relationship between severity of the liver lesions and drug dosage. Central chromatolysis, scattered neuronal necrosis, and mild spongy changes were observed in five regions of the brain that were chosen for sectioning (motor cortex, cerebellar nuclei, midbrain nuclei, and hindbrain nuclei at two separate levels). Severity of lesions in brain was dose-dependent, and cerebral cortex was the most vulnerable area. Haematologic tests showed lower values for hematocrit and red blood cell count dose-dependently. In conclusion, artemisinin is a promising drug for prevention and control of coccidiosis in broiler chickens and its side effects are not too much serious especially at therapeutic doses.  相似文献   
126.
The aim of this study was to evaluate the effects of different concentrations of lycopene and cysteamine on characteristics of sperm, liquid peroxidation and enzymatic activities in seminal plasma of canine semen preserved at 5°C for 72 hr. The semen samples were divided into eight aliquots: control, control sham (dimethyl sulfoxide 5%), lycopene groups (250, 500 and 750 µg/ml) and cysteamine groups (2.5, 5 and 10 mM). Motility, viability, membrane integrity, DNA integrity, total antioxidant capacity (TAC) and malondialdehyde (MDA) levels were evaluated. Progressive motility and total motility were higher with the 500 and 750 µg/ml lycopene concentrations, respectively, compared to the control group and the cysteamine groups following 72 hr of storage in the liquid storage. Motility characteristics, viability and hypo-osmotic swelling test (HOST) percentages were significantly improved in 500 µg/ml lycopene compared to other groups. The 500 and 750 µg/ml lycopene concentrations, respectively, showed significantly reduced percentages of spermatozoa with DNA integrity compared to the control group. The 500 and 750 µg/ml lycopene concentrations, respectively, led to the significant decrease of MDA levels. The 500 µg/ml lycopene enhanced TAC levels after 48 and 72 hr that was not observed in other groups. In conclusion, the findings of this study showed that lycopene supplementation in canine semen extenders improved canine semen parameters and TAC levels and decreased MDA levels in the chilling process.  相似文献   
127.
Tropical Animal Health and Production - Contagious caprine pleuropneumonia (CCPP) is one of the most fatal and contagious diseases of goats. To date, the occurrence of CCPP in Egypt has not been...  相似文献   
128.
Mass flux assessment can provide information that is essential for a sustainable management of elements in agricultural soils. In this article, we present an assessment of regional-scale averages of zinc (Zn) fluxes into agricultural soils and crops of central Iran for the period 1997–2011, using available databases such as regional agricultural statistics. The basic units of the balances were 15 townships of the provinces Qom, Isfahan and Fars. Averaged over the entire study region, the net Zn input into arable soil resulting from all fertilizer inputs – Zn removal with harvested crops was 1515 g ha?1 yr?1 across the entire region, with a range of 438–3009 g ha?1 yr?1 among townships. Estimated average Zn inputs with manure, mineral fertilizers, sewage sludge and compost were 1254, 531, 19 and 7 g ha?1 yr?1, respectively. The input-to-output ratio of these fluxes ranged from 1.8 to 12.9 among townships and averaged 6.1 for the entire study area. Considering that outputs other than with crop harvests are minor, Zn stocks are rapidly building up in the soils of the study region. Uncertainties in the manure and crop removal data were the main sources of estimation uncertainty in this study.  相似文献   
129.
Aluminum toxicity and boron deficiency are the major factors that limit plant growth and development in acid soils and in B-deficient soils. Root growth inhibition is an early symptom of AI toxicity and B deficiency. Effects of AI and B supply and their interaction on the growth of wheat (Triticum aestivum L.) seedlings were investigated using hydroponics. Fifteen wheat cultivars commonly grown in Bangladesh were used and found to differ considerably in their tolerance to AI toxicity and B deficiency. The relative root length of all the wheat cultivars at 50 µM AI (pH 4.5) ranged from 27 to 71% relative to the control (0 µM AI). Among the cultivars, Inia66 and Kalyansona were found to be the most Al-tolerant and sensitive cultivars, respectively, based on the data of relative root length, malate exudation and AI content of roots. Malate was detected in all the cultivars in the presence of 100 µM AI (pH 4.3). Inia66 exuded a 6-fold larger amount of malate and the AI content of roots was 4 times lower than that in Kalyansona. The vigorous seedling growth was observed at 40 µM B among the series of B treatments. Considerable cultivar differences in response to 40 µM B were observed among the 15 cultivars. Kalyansona was considered to be the most sensitive and Kheri the most tolerant to B deficiency. The interaction effects of B ( 40 and 200 µM) and AI (50 µM) on seedling growth were also examined in Inia66 and Kalyansona. Root growth was inhibited in the presence of Al but B supply especially at 200 µM B in the Kalyansona cultivar caused a slight improvement.  相似文献   
130.
Beet yellows virus (BYV), beet mild yellowing virus (BMYV), beet chlorosis virus (BChV), and beet mosaic virus (BtMV) cause virus yellows (VY) disease in sugar beet. The main virus vector is the aphid Myzus persicae. Due to efficient vector control by neonicotinoid seed treatment over the last decades, there is no current knowledge regarding virus species distribution. Therefore, Europe-wide virus monitoring was carried out from 2017 to 2019, where neonicotinoids were banned in 2019. The monitoring showed that closterovirus BYV is currently widely spread in northern Europe. The poleroviruses BMYV and BChV were most frequently detected in the northern and western regions. The potyvirus BtMV was only sporadically detected. To study virus infestation and influence on yield, viruses were transmitted to sugar beet plants using viruliferous M. persicae in quadruplicate field plots with 10% inoculation density simulating natural infection. A plant-to-plant virus spread was observed within 4 weeks. A nearly complete infection of all plants was observed in all treatments at harvest. In accordance with these findings, a significant yield reduction was caused by BMYV and BChV (−23% and −24%) and only a moderate reduction in yield was observed for BYV (−10%). This study showed that inoculation at low densities mimics natural infection, and quick spreading induced representative yield effects. Within the background of a post-neonicotinoid era, this provides the basis to screen sugar beet genotypes for the selection of virus tolerance/resistance and to test the effectiveness of insecticides for the control of M. persicae with a manageable workload.  相似文献   
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