颗粒料和破碎料饲喂小虾的效果     

邱榕生  李可 《中国畜牧兽医》2002,29(3):21-22

虾料的外在物理特性变化范围很大 ,但在是否为小虾生长所必需这一问题上 ,还存在着疑问。相关的试验结果表明使用颗粒状开食料的斑节对虾 ( Penaeus monodon)幼苗的生长性能要显著好于饲喂破碎料的。饲喂 2种粒度碎粒状开食料的罗氏沼虾 ( Macrobrachium rosenbergii)间的生长性能无差异 ,因此得出结论 :幼虾阶段使用 2种粒度的破碎料是没有必要的。试验结果还表明颗粒料的长度 (长或短 )对斑节对虾的生长没有影响。目前 ,小虾的商业化养殖仍是一个新兴行业 ,相关的知识还很缺乏。因此 ,生产实践中往往按主观判断行事 ,特别是决定饲料的物…  相似文献   

Laparoskopische Untersuchungen zum Tertiärfollikelwachstum im Brunstzyklus beim Merinofleischschaf     

Karl-Heinz Kaulfuß  reas Richter  Joachim Schulz 《Reproduction in domestic animals》1994,29(1):22-37

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Book reviews     

Joachim Keller  L. J. G. van der Maesen 《Genetic Resources and Crop Evolution》1995,42(3):291-292

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Differential clustering of Mycoplasma mycoides subsp. mycoides SC strains by PCR-REA of the bgl locus     

Vilei EM  Frey J 《Veterinary microbiology》2004,100(3-4):283-288

In order to develop a specific tool differentiating the African field strains of Mycoplasma mycoides subsp. mycoides SC from other potentially less virulent strains, including the vaccine strains, we have developed a PCR followed by a restriction enzyme analysis (PCR–REA). This approach also differentiates the African field strains from the Australian strains and the type strain PG1. The genomic marker detected by the PCR–REA is based on a single nucleotide change in the bgl gene that codes for 6-phospho-β-glucosidase (Bgl), an enzyme that is involved in sugar metabolism.  相似文献   

Colonisation of Escherichia coli O157:H7 on squamous epithelial cells at the rectal-anal junction     

Pohlenz JF  Dean-Nystrom EA 《The Veterinary record》2004,155(8):248

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Detection of Isospora suis (Biester and Murray 1934) in piglet faeces--comparison of microscopy and PCR     

Joachim A  Ruttkowski B  Zimmermann M  Daugschies A  Mundt HC 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2004,51(3):140-142

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Conservation of the uvrC gene sequence in Mycoplasma bovis and its use in routine PCR diagnosis   总被引：1，自引：0，他引：1  

Thomas A  Dizier I  Linden A  Mainil J  Frey J  Vilei EM 《Veterinary journal (London, England : 1997)》2004,168(1):100-102

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X-linked Chronic Granulomatous Disease     

Roesler J 《The Journal of small animal practice》2006,47(9):557

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Simultaneous determination of ethidimuron, methabenzthiazuron, and their two major degradation products in soil     

Lagarde F  Puetz T  Dressel J  Fuehr F 《Journal of agricultural and food chemistry》2006,54(20):7450-7459

An analytical method has been developed for the quantification of two herbicides (ethidimuron and methabenzthiazuron) and their two main soil derivatives. This method involves fluidized-bed extraction (FBE) prior to cleanup and analysis by reverse-phase liquid chromatography with UV detection at 282 nm. FBE conditions were established to provide efficient extraction without degradation of the four analytes. (14)C-labeled compounds were used for the optimization of extraction and purification steps and for the determination of related efficiencies. Extraction was optimal using a fexIKA extractor operating at 110 degrees C for three cycles (total time = 95 min) with 75 g of soil and 150 mL of a 60:40 v/v acetone/water mixture. Extracts were further purified on a 500 mg silica SPE cartridge. Separation was performed on a C18 Purosphere column (250 mm x 4 mm i.d.), at 0.8 mL min(-1) and 30 degrees C with an elution gradient made up of phosphoric acid aqueous solution (pH 2.2) and acetonitrile. Calibration curves were found to be linear in the 0.5-50 mg L(-1) concentration range. Besides freshly spiked soil samples, method validation included the analysis of samples with aged residues. Recovery values, determined from spiked samples, were close to 100%. Limits of detection ranged between 2 and 3 microg kg(-1) of dry soil and limits of quantification between 8 and 10 microg kg(-1) of dry soil. An attempt to improve these performances by using fluorescence detection following postcolumn derivatization by orthophthalaldehyde-mercaptoethanol reagent was unsuccessful.  相似文献   

Distribution of RTX toxin genes in strains of [Actinobacillus] rossii and [Pasteurella] mairii     

Mayor D  Korczak BM  Christensen H  Bisgaard M  Frey J  Kuhnert P 《Veterinary microbiology》2006,116(1-3):194-201

Strains of [Actinobacillus] rossii, [Pasteurella] mairii and [Pasteurella] aerogenes can be isolated from abortion in swine. The RTX toxin Pax has previously been found only in those [P.] aerogenes strains isolated from abortion. Nothing is known about RTX toxins in field isolates of the other two species. To gain insight into the distribution of selected RTX toxin genes and their association with abortion, PCR screening for the pax, apxII and apxIII operons on 21 [A.] rossii and seven [P.] mairii isolates was done. Since species can be phenotypically misidentified, the study was backed up by a phylogenetic analysis of all strains based on 16S rRNA, rpoB and infB genes. The pax gene was detected in all [P.] mairii but not in [A.] rossii strains. No apx genes were found in [P.] mairii but different gene combinations for apx were detected in [A.] rossii strains. Most of these strains were positive for apxIII, either alone or in combination with apxII. Whereas pax was found to be associated to strains from abortion no such indication could be found with apx in [A.] rossii strains. Phylogenetically [A.] rossii strains formed a heterogeneous cluster separated from Actinobacillus sensu stricto. [P.] mairii strains clustered with [P.] aerogenes but forming a separate branch. The fact that [P.] aerogenes, [P.] mairii and [A.] rossii can phylogenetically clearly be identified and might contain distinct RTX toxin genes allows their proper diagnosis and will further help to investigate their role as pathogens.  相似文献