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41.
现已证明,在酵母中产生的一种新型的6-植酸酶比其他在市场上供应的植酸酶的效率至少高20%。因为6-植酸酶与其他商品化的植酸酶相比,可进一步减少无机磷源的使用,从而降低生产成本以及磷的污染。 相似文献
42.
T. Honda T. Nomura Y. Yamaguchi F. Mukai 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2004,121(4):242-252
The gene pool of the Japanese Black cattle has been completely closed to foreign breeds during the last 100 years. Genetic diversity of the Japanese Black cattle from 1960 to 2000 was monitored with three estimates of effective number of ancestors. Founder genome equivalent (Nge) accounts for all the causes of reduction of diversity. Effective number of founders (Nef) and non‐founders (Nenf) explain reduced diversity because of unequal genetic contributions of founders and random genetic drift in non‐founders, respectively. Further examination using gene dropping simulation was conducted to obtain information on survival of founder alleles. Unique founder alleles were dropped down along the actual pedigree with Monte Carlo procedure following Mendelian segregation rules, and generated genotypes of all the current live animals (612 959 heads). Pedigree records consisted of 2 075 188 animals was used for these analysis. The estimates of three effective numbers (Nef, Nge, and Nenf) decreased from 418.6 to 50.3, 86.6 to 7.3, and 109.2 to 8.5, respectively, during the period 1960–2000. The increasing differences between two kinds of genetic diversity indices derived from Nge and Nef showed that large part of the reduced diversity from 1980 was attributed to genetic drift caused by the intensive use of particular limited number of sires. In gene dropping analysis, probabilities of extinction of founder alleles were derived from their distributions of frequency in the current animals. Several founders showed low probabilities of allele extinction, irrespective of their relatively low genetic contributions. This suggests that these founders have lineages through which their alleles are surely transmitted to the current breed. The use of these founders as a strategy for recovering the genetic diversity was discussed. 相似文献
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The usefulness of the intradermal test (IDT) and the serological allergy test (SAT) for detecting antigen‐specific IgE in allergic cats has not yet been established. In this study, we compared the results of IDT with those of SAT and evaluated the clinical usefulness of the two tests for detecting possible allergens in allergic cats. IDT and SAT using eight antigens were performed on 22 cats with intense pruritus after excluding ectoparasites and performing diet elimination tests. Approximately 50% of the cats reacted to at least one allergen by either IDT or SAT, and 36.4% of the cats reacted on both IDT and SAT. In contrast, seven healthy cats did not show any reactions on IDT or SAT. The most commonly detected allergen in both tests was house dust mites (IDT, 36.4%; SAT, 40.9%). Five cats reacted to one allergen and the others reacted to more than one allergen with IDT. Three cats reacted to one allergen with SAT. The following percentage agreement between the results of the two tests was calculated: house dust mites (86.4%), cat fleas (63.6%), grass mix (86.4%), common mugwort (81.8%), cat epithelia (90.9%), ragweed (86.4%), Japanese cedar (90.9%), and plantain (81.8%). The overall mean percentage agreement was 83.5%. In summary, the present study showed good agreement between IDT and SAT for cats, and SAT may be more sensitive than IDT, but less specific for detecting sensitized allergens. Funding: Self‐funded. 相似文献
45.
通过对4个安装了简易T型瘘管的断奶仔猪研究表明,添加植酸酶并没有提高玉米-豆粕型日粮(试验组1)、小麦-豆粕型日粮(试验组2)和大麦-豌豆-菜籽粕型日粮(试验组4)粗蛋白和氨基酸的回肠表观消化率(AID),而使小麦-豆粕-菜粕型日粮的粗蛋白和氨基酸回肠表观消化率或粗蛋白和消化能的总消化道表观消化率(ATTD)得到了显著的提高(P<0.05)或呈提高的势态(P<0.10)。这些结果表明,氨基酸对细菌性植酸酶的反应因子取决于日粮的组成。 相似文献
46.
粪肥施用为土壤输入大量有机质与养分,能影响土壤团聚体的形成和稳定性,大部分研究主要认为粪肥施用促进土壤大粒径团聚体的形成(marcoaggregate,≥0.25 mm),但进一步细分是对大团聚体(large marcoaggregate,>2 mm)还是小团聚体(small marcoaggregate,2 ~ 0.25 mm)的影响更大,研究存在较大差异。本文使用Meta分析收集了36篇相关文献,共267个团聚体数据,发现施用粪肥能显著增加土壤大团聚体和小团聚体含量,分别增加了95% 和17%,同时减少了土壤微团聚体(microaggregates,0.25 ~ 0.053 mm)和土壤粉黏颗粒(silt-plus and clay-size particles,<0.053 mm)含量,分别减少了14% 和20%。本文还从土壤因素、粪肥因素、气候因素3个角度的解释变量来分析粪肥施用对土壤团聚体影响不同的原因,结果发现土壤类型、土壤pH、粪肥种类和年均气温、年均降水量是造成不同研究结果差异的主要原因。 相似文献
47.
H. KATAE K. KOUNO Y. TAKASE H. MIYAZAKI M. HASHIMOTO M. SHIMIZU 《Journal of fish diseases》1979,2(4):321-335
Abstract. The activity of piromidic acid (PA, 8-ethyl-5, 8-dihydro-5-oxo-2-prior lidinopyrido [2,3–d] pyrimidine-6-carboxylic acid) against bacteria in fish was evaluated in vitro and in vivo .
In vitro , PA was effective against a wide range of pathogenic bacteria stocked in this laboratory and freshly isolated from fish. PA was active against organisms showing multiple drug-resistance and showed no cross-resistance to chloramphenicol, tetracycline and sulfamonomethoxine.
In vivo , orally administered PA was effective against experimental infections with Aeromonas hydrophila and Vibrio spp. in goldfish and eels. The efficacy of PA against these infections was equal to or higher than that of chloramphenicol, and higher than that of tetracycline. Distribution of PA in the Ash was investigated by bioassay and autoradiography. In the bioassay, orally administered PA was easily absorbed and distributed in the blood and tissues of major organs within 1 h after the administration. Peak levels were attained 2 to 4 h post dosing, and no residue was detected in the blood and tissues 48 h post dosing. The results obtained from the autoradiographic investigation in goldfish were similar to those from the bioassay. Therapeutic levels of PA were well tolerated by fish when administered with feed. 相似文献
In vitro , PA was effective against a wide range of pathogenic bacteria stocked in this laboratory and freshly isolated from fish. PA was active against organisms showing multiple drug-resistance and showed no cross-resistance to chloramphenicol, tetracycline and sulfamonomethoxine.
In vivo , orally administered PA was effective against experimental infections with Aeromonas hydrophila and Vibrio spp. in goldfish and eels. The efficacy of PA against these infections was equal to or higher than that of chloramphenicol, and higher than that of tetracycline. Distribution of PA in the Ash was investigated by bioassay and autoradiography. In the bioassay, orally administered PA was easily absorbed and distributed in the blood and tissues of major organs within 1 h after the administration. Peak levels were attained 2 to 4 h post dosing, and no residue was detected in the blood and tissues 48 h post dosing. The results obtained from the autoradiographic investigation in goldfish were similar to those from the bioassay. Therapeutic levels of PA were well tolerated by fish when administered with feed. 相似文献
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