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设施栽培油桃物候期内温室内外温度变化规律研究 总被引:1,自引:0,他引:1
基于2015年1-5月观测的设施栽培油桃(Prunus persica var.nectarina Maxim)物候期和日光温室内外气温、地温等数据,系统研究了油桃在整个物候期内温室内外气温、地温的变化规律。结果表明,温室栽培油桃的物候期较露地栽培油桃提前50 d左右。油桃萌芽、开花期,温室内的平均气温可达到11.8~13.7℃,最低气温在5℃左右,此气温水平较好满足了油桃萌芽、开花的需要。果实膨大期及成熟期内,温室内平均气温为14.9~24.1℃,但最高气温有时达30℃以上,应注意及时通风降温,延长温室的通风降温时间。温室内外气温在不同天气条件下日变化均呈"单峰"型,晴天温室内外日温差比阴天大,温室内的气温始终高于室外的气温。1月下旬至3月中旬,日光温室内5 cm土层的平均地温为13.5~17.2℃,地温不能满足油桃根系生长发育的需求。不同天气条件下日光温室内外地温的日变化趋势与气温变化基本一致,温室外地温日变化与温室外气温日变化具有相关性;温室内地温日变化较平稳,最高地温较最高气温出现的时间存在滞后现象。 相似文献
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生长激素(PST)脂质体的制备 总被引:5,自引:0,他引:5
用冰冻熔融法制备脂质体,包封率可达29%,当n(卵磷脂)∶n(胆固醇)=5∶2(摩尔比),超声时间3 min,中性环境,冰冻24 h或4 ℃贮藏3 d,其稳定性良好,包封率(29.1±0.4)%,变化不显著。 相似文献
24.
Effect of fermentation on the nutritive value of sesame seed meal in the diets for rohu, Labeo rohita (Hamilton), fingerlings 总被引:1,自引:0,他引:1
Six isonitrogenous (350 g kg−1 crude protein) and isoenergetic (17573 kJ kg−1 ) experimental diets incorporating raw and fermented sesame ( Seasamum indicum ) seed meal at 200, 300, and 400 g kg−1 into a fishmeal based diet were fed to rohu Labeo rohita fingerlings for 60 days and the growth performance and feed utilization efficiency of the fish was studied. The antinutritional factor phytic acid, from raw sesame seed meal, could be reduced below detection limit by fermentation with lactic acid bacteria ( Lactobacillus acidophilus ). Fermentation of the oilseed meal resulted in reduction of the tannin content from 20 to 10 g kg−1 . In terms of growth response, feed conversion ratio and protein efficiency ratio, a diet containing 400 g kg−1 fermented sesame seed meal resulted in a significantly ( P < 0.01) best fish performance. In general, growth and feed utilization efficiencies of fish fed fermented sesame seed meal diets were superior to those fed raw oilseed meal diets. Apparent protein digestibility (APD) values decreased with increasing levels of raw oilseed meal. APD was, however, significantly ( P < 0.01) higher at all levels of incorporation of fermented sesame seed meal, while diets containing raw oilseed meal resulted in poor protein and lipid digestibility. Carcass protein and lipid contents of fish fed fermented sesame seed meal diets increased with increasing level of incorporation, being highest with 400 g kg−1 fermented oilseed meal-containing diet. The results showed that sesame seed meal may be incorporated in carp diets up to 200 g kg−1 and 400 g kg−1 in raw and treated (fermented) forms respectively. 相似文献
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RR Moura ES Lopes‐Junior DIA Teixeira IA Serova LE Andreeva LM Melo VJF Freitas 《Reproduction in domestic animals》2010,45(5):e101-e106
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
30.
OBJECTIVE: To define the relationship between clinical expression of a type-1 von Willebrand disease phenotype and genotype at 2 von Willebrand factor marker loci in Doberman Pinschers. ANIMALS: 102 client-owned Doberman Pinschers. PROCEDURES: Dogs were recruited on the basis of plasma von Willebrand factor concentration, clinical history, and pedigree. Blood samples and response to a history questionnaire were obtained for each dog. Plasma von Willebrand factor concentration was measured by use of an ELISA, and genotyping was performed via polymerase chain reaction for 1 intragenic and 1 extragenic von Willebrand factor marker. Amplification product size was determined by use of polyacrylamide gel electrophoresis (intragenic marker) or automated sequence analysis (extragenic marker). Western blots were prepared from a subset of dogs with low plasma von Willebrand factor concentration to evaluate multimer distribution. RESULTS: Strong associations were detected between plasma von Willebrand factor concentration and von Willebrand factor marker genotype. Twenty-five dogs had substantial reduction in plasma von Willebrand factor concentration and multiple hemorrhagic events. All were homozygous for a 157-base-pair intragenic marker allele and homozygous or compound heterozygous for 1 of 4 extragenic marker alleles. These marker genotypes were exclusively detected in dogs with low plasma von Willebrand factor concentration, although some dogs with these genotypes did not have abnormal bleeding. CONCLUSIONS AND CLINICAL RELEVANCE: Type-1 von Willebrand disease in Doberman Pinschers is associated with the von Willebrand factor gene locus; however, the expression pattern in this breed appears more complex than that of a simple recessive trait. 相似文献