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121.
A PCR-based method was developed for the identification and detection of Phytophthora capsici in pepper plants. Three PCR primers (CAPFW, CAPRV1 and CAPRV2) specific for P. capsiciwere designed based on the sequence of its internal transcribed spacer regions. CAPFW/CAPRV1 amplify a 452 bp product from P. capsici DNA whereas CAPFW/CAPRV2 a 595 bp fragment; neither set amplifies DNA from pepper or several fungi pathogenic to pepper. In conventional (single-round) PCR, the limit of detection was 5 pg DNA for both primer sets, whereas in nested PCR the detection limit for both was of 0.5 fg. However, when the dilution series of target DNA were spiked with plant DNA, amplification declined two-fold in both conventional and nested PCR. The CAPFW/CAPRV2 set in conventional PCR was used to detect P. capsici DNA in inoculated plants. Detection occurred as soon as 8h post-inoculation in stem samples from infected but still symptomless plants. The method was also tested to detect fungal DNA in infected soils.  相似文献   
122.
The objectives were to evaluate the silage quality of sugarcane silage enriched (as fed) with corn grain ground (10%), urea (1.5%), and mineral premix (0.5%) and its effects as a feed supplement on growth performance of beef steers grazing stargrass. Firstly, in micro-silages, whole sugarcane enriched with corn grain, urea, and minerals (WSCE) were ensilaged by 0, 20, 40, and 60 days. Crude protein (CP) and lactic acid (LA) increased linearly (P < 0.05) and true protein decreased linearly (P < 0.05) as fermentation time increased. The pH values in silages were affected quadratically by fermentation time. Thus, after a 20-day fermentation, the pH values were below 4.5. Secondly, in micro-silos WSCE and stem sugarcane enriched with corn grain, urea, and minerals (SSCE) with and without calcium propionate were ensilaged by 30 days, but it did not affect any chemical composition trait in the silage. The SCCE silages had higher CP and LA and lower pH than WSCE silages. Finally, for 120 days, 20 beef steers (378 ± 33 kg initial BW) grazing stargrass were supplemented (daily by 1-h free access) with WSCE silage. Supplemental silage increased total dry matter intake, total gain, and the average daily gain, without any affectation on feed conversion and total tract digestion of dry matter. It is concluded that whole sugarcane silage is an alternative feed supplement to improve growth performance in beef steers grazing stargrass.  相似文献   
123.
Fermentation performance of eight waxy, seven nonwaxy soft, and 15 nonwaxy hard wheat cultivars was compared in a laboratory dry‐grind procedure. With nitrogen supplements in the mash, the range of ethanol yields was 368–447 L/ton. Nonwaxy soft wheat had an average ethanol yield of 433 L/ton, higher than nonwaxy hard and waxy wheat. Conversion efficiencies were 91.3–96.2%. Despite having higher levels of free sugars in grain, waxy wheat had higher conversion efficiency than nonwaxy wheat. Although there was huge variation in the protein content between nonwaxy hard and soft wheat, no difference in conversion efficiency was observed. Waxy cultivars had extremely low peak viscosity during liquefaction. Novel mashing properties of waxy cultivars were related to unique pasting properties of starch granules. With nitrogen supplementation, waxy wheat had a faster fermentation rate than nonwaxy wheat. Fermentation rates for waxy cultivars without nitrogen supplementation and nonwaxy cultivars with nitrogen supplementation were comparable. Ethanol yield was highly related to both total starch and protein content, but total starch was a better predictor of ethanol yield. There were strong negative relationships between total starch content of grain and both yield and protein content of distillers dried grains with solubles (DDGS).  相似文献   
124.
A 10‐year‐old male captive tiger (Panthera tigris) developed right‐sided facial asymmetry and enlargement. Computed tomography revealed a destructive mass of the right maxillary bone with right nasal cavity involvement. Histopathology indicated a spindle cell sarcoma. A single fraction of 22 Gy using stereotactic radiotherapy was prescribed. After treatment, the facial conformation returned to normal and the tiger resumed normal behavior. Diagnostics 4 months later indicated severe metastatic disease. Humane euthanasia and necropsy were performed. This is the first case utilizing stereotactic radiotherapy for the treatment of cancer in a tiger.  相似文献   
125.
The objective of this study was to examine the effect of donor breed on pronuclear‐stage embryo yield to be used for DNA microinjection in a transgenesis goat program. Twelve Canindé and twelve Saanen goats were heat synchronized using a progestagen‐cloprostenol treatment. Forty‐eight hours before the sponge removal, superovulation was induced with a total administration of 4.4 mg/kg bodyweight NIH‐FSH‐P1, given twice daily in decreasing doses over 3 days. In addition, goats received 100 μg of GnRH and they were hand‐mated at 36 and 48 h after progestagen removal. Embryo recovery was performed by oviduct flushing at 72 h after sponge removal. Embryos were microinjected with a DNA construct and noticeable swelling of the nuclei was the criterion for successful microinjection. The total diameter, cytoplasm diameter, zona pellucida thickness and pronuclei diameter were measured for each microinjected embryo. A higher (p < 0.05) percentage of fertilized ova was observed in Canindé (89.9%) than Saanen (36.2%) goats. In addition, Canindé donors produced a higher percentage of pronuclear embryos when compared with Saanen: 72.5% vs 20.6% (p < 0.05), respectively. Successful microinjection was verified in 96.7% and 73.3% of times in Canindé and Saanen embryos, respectively (p < 0.05). Significant differences were observed for all morphometric parameters except for cytoplasm diameter. In conclusion, under our study experimental conditions, Canindé were more efficient than Saanen goats concerning the pronuclear embryo yield and manipulation. The use of Canindé goats in transgenesis programs could be increase the interest in their breeding and could be contribute to saving them from extinction.  相似文献   
126.
The pharmacokinetics (PK) of moxifloxacin in healthy white New Zealand rabbits was studied following intravenous (IV) and subcutaneous (SC) administration routes as well as a SC long-acting poloxamer 407 gel formulation (SC-P407). Moxifloxacin concentrations were determined by high-performance liquid chromatography assay with fluorescence detection. Mean half-life for IV, SC and SC-P407 routes was 2.15, 5.41 and 11.09 h. Clearance value after IV dosing was 0.78 l/kg/h. After SC administration, the mean absolute bioavailability was 117% and the C(max) was 1.61 +/- 0.49 mg/l. After SC-P407 administration, the bioavailability was 44% and the C(max) 1.83 was +/-0.62 mg/l. No adverse effects were observed in any of the rabbits following IV, SC and SC-P407 administration of moxifloxacin. Minimal inhibitory concentrations of moxifloxacin against different strains of Staphylococcus aureus from different european countries were used to compute the main pharmacodynamic (PD) surrogate markers of efficacy. The high tolerability of this SC-P407 formulation and the favourable PK behaviour such as the long half-life, acceptable bioavailability and excellent PK-PD ratios achieved indicate that it is likely to be effective in rabbits.  相似文献   
127.
Discrimination between nestmates and non‐nestmates in social insects is thought to rely on the pattern of cuticular hydrocarbons. We investigated the cuticular hydrocarbon profiles of 2 parapatric sibling ant species, Temnothorax nylanderi (Förster, 1850) and Temnothorax crassispinus (Karavaiev, 1926), and their hybrid. We found that although the profiles show considerable similarities, a discriminant analysis based on the relative peak areas of cuticular hydrocarbons separates the 3 taxa. The profiles of hybrids were not consistently intermediate between those of the paternal species, suggesting either non‐additive interactions among the parental biosynthetic pathways or systematic differences in environment‐derived odor cues.  相似文献   
128.
Black snook, Centropomus nigrescens, have been identified as a promising candidate for aquaculture although, like many of the Centropomid species, high mortality associated with early larval stages presents a significant bottleneck to their commercialization. The digestive capacity of black snook larvae throughout the first 37 d after hatch (d.a.h.) was evaluated by quantifying digestive enzyme activities using biochemical techniques. Results showed that black snook larvae have alkaline proteases at hatching, which are known to be important during the first days of feeding for digestion. Toward the end of the study, acid proteases concentration increased (37 d.a.h.). Enzymes for lipid digestion, pancreatic lipase and bile salt‐activated lipase, were already present in the larvae before exogenous feeding commenced, and their activity increased with age and growth (length). Intracellular digestion, measured as the activity of leucine‐alanine peptidase, was high early on (5 d.a.h.) and decreased as development progressed (next 32 d). In contrast, alkaline phosphatase activity was lowest at first feeding and subsequently increased with age. Overall patterns in enzyme activity suggest the possibility of live feed weaning before 32 d.a.h. if artificial diets can be properly balanced.  相似文献   
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