Harvest of Channel Catfish with an Electrically Enhanced Seine     

C. Douglas  Minchew  Kenneth K.  McDill Rachel V.  Beecham S. D. Filip To   《Journal of the World Aquaculture Society》2004,35(4):543-545

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Leishmaniasis phytotherapy. Nature's leadership against an ancient disease.     

P B de Carvalho  E I Ferreira 《Fitoterapia》2001,72(6):599-618

The use of phytotherapy to treat human diseases has its roots in pre-historical times. Despite the modern advances achieved in the field of synthetic chemistry, the most efficient drugs available have their genesis directly or indirectly related with the vegetal kingdom. Indigenous communities have long used plant extracts to treat illnesses. Many of these extracts have shown effective action, with new bioactive compounds being extracted and screened every year. These extracts have also proven to be good sources of therapeutic agents to the treatment of Leishmaniasis. This work highlights some of these agents, while trying to emphasize the importance of plants as a source of new and powerful drugs against this widespread disease.  相似文献   

Pasteurella haemolytica A1 and Bovine Respiratory Disease: Pathogenesis     

Laurence O. Whiteley DVM  PhD    Samuel K. Maheswaran BVSc  PhD    Douglas J. Weiss DVM  PhD    Trevor R. Ames DVM  MS  Mathur S. Kannan BVSc  PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1992,6(1):11-22

The severe fibrinonecrotic pneumonia associated with pneumonic pasteurellosis usually results from colonization of the lower respiratory tract by Pasteurella haemolytica biotype A, serotype 1(A1). Despite recent research efforts, the authors lack a detailed understanding of the interactions and host response to P. haemolytica in the respiratory tract. The authors hypothesize that management and environmental stress factors or viral infection alters the upper respiratory tract (URT) epithelium allowing P. haemolytica to colonize the epithelium. Once the URT is colonized, large numbers of organisms enter the lung where they interact with alveolar macrophages. Endotoxin, released from the bacteria, crosses the alveolar wall where it activates pulmonary intravascular macrophages, endothelium, neutrophils, lymphocytes, platelets, complement, and Hageman factor leading to complex interactions of cells and mediators. It is the progression of this inflammatory response with neutrophil influx that is ultimately responsible for the pulmonary injury. Leukotoxin is a major virulence factor of P. haemolytica that allows it to survive by destroying phagocytic cells. At subcytolytic concentrations it may also enhance the inflammatory response by activating cells to produce mediators and release reactive oxygen metabolites and proteases.  相似文献   

Biofilm bacteria: formation and comparative susceptibility to antibiotics   总被引：17，自引：0，他引：17       下载免费PDF全文

Merle E. Olson  Howard Ceri  Douglas W. Morck  Andre G. Buret    Ronald R. Read 《Canadian journal of veterinary research》2002,66(2):86-92

The Calgary Biofilm Device (CBD) was used to form bacterial biofilms of selected veterinary gram-negative and gram-positive pathogenic bacteria from cattle, sheep, pigs, chicken, and turkeys. The minimum inhibitory concentration (MIC) and minimum biofilm eradication concentration (MBEC) of ampicillin, ceftiofur, cloxacillin, oxytetracycline, penicillin G, streptomycin, tetracycline, enrofloxacin, erythromycin, gentamicin, tilmicosin, and trimethoprim-sulfadoxine for gram-positive and -negative bacteria were determined. Bacterial biofilms were readily formed on the CBD under selected conditions. The biofilms consisted of microcolonies encased in extracellular polysaccharide material. Biofilms composed of Arcanobacterium (Actinomyces) pyogenes, Staphylococcus aureus, Staphylococcus hyicus, Streptococcus agalactiae, Corynebacterium renale, or Corynebacterium pseudotuberculosis were not killed by the antibiotics tested but as planktonic bacteria they were sensitive at low concentrations. Biofilm and planktonic Streptococcus dysgalactiae and Streptococcus suis were sensitive to penicillin, ceftiofur, cloxacillin, ampicillin, and oxytetracycline. Planktonic Escherichia coli were sensitive to enrofloxacin, gentamicin, oxytetracycline and trimethoprim/ sulfadoxine. Enrofloxacin and gentamicin were the most effective antibiotics against E. coli growing as a biofilm. Salmonella spp. and Pseudomonas aeruginosa isolates growing as planktonic populations were sensitive to enrofloxacin, gentamicin, ampicillin, oxytetracycline, and trimethoprim/sulfadoxine, but as a biofilm, these bacteria were only sensitive to enrofloxacin. Planktonic and biofilm Pasteurella multocida and Mannheimia haemolytica had similar antibiotic sensitivity profiles and were sensitive to most of the antibiotics tested. The CBD provides a valuable new technology that can be used to select antibiotics that are able to kill bacteria growing as biofilms.  相似文献   

Genetics of Body Color in Tilapia mossambica     

Douglas  Tave  Mahmoud  Rezk  R. Oneal  Smitherman 《Journal of the World Aquaculture Society》1989,20(4):214-222

Gold, bronze, and black (normal pigmentation) body colors in Tilapia mossambica are controlled by a single autosomal gene with incomplete dominant gene action: GG fish are black gg fish are gold; Gg fish are bronze. Because gold body color is produced by the recessive genotype, it is easy to produce and to maintain a truebreeding population of gold T. mossambica for commercial purposes. If all other colors are culled, the population will breed true, because gold × gold will always produce 100% gold offspring. The G gene will be a valuable genetic marker for many genetic studies, such as the production of gynogenetic T. mossambica .  相似文献   

SAHA and hemangiosarcoma: another view     

Douglas H. Thamm 《Veterinary and comparative oncology》2005,3(2):101-101

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Book review, Landscape Erosion and Evolution Modeling     

Douglas M. Johnston 《Landscape Ecology》2003,18(2):210-211

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Purification and some properties of Papaya meleira virus, a novel virus infecting papayas in Brazil     

E. Maciel-Zambolim †  S. Kunieda-Alonso  K. Matsuoka  M. G. de Carvalho  F. M. Zerbini 《Plant pathology》2003,52(3):389-394

'Meleira', or 'sticky disease', is currently the most damaging papaya disease in the mid-eastern Brazilian growing regions. Consistent disease transmission via latex injection, presence of similar isometric particles in the laticiferous vessels of diseased plants, and detection of double-stranded DNA in naturally and experimentally infected papaya trees suggest that a virus is the causal agent. Conclusive evidence for viral aetiology was previously lacking, mostly because every attempt to purify the putative virus from infected papayas had failed. Following the successful purification and partial characterization of the meleira virus, healthy papaya seedlings injected with purified virus particles later developed typical symptoms of the disease. Negatively stained, isometric, full and 'empty' purified virus particles measured 42 and 38 nm, respectively. The viral genome was a single dsRNA molecule of about 12 kbp. Several capsid proteins, ranging in size from 14·4 to 45 kDa, were consistently revealed by PAGE. Papaya meleira virus (PMeV) appears to represent a novel group of viruses, with no known similar counterpart among known plant-, vertebrate-, invertebrate- or prokaryote-infecting viruses.  相似文献   

应用绵羊粪便的近红外光谱方程评定其日粮的可消化有机物   总被引：1，自引：0，他引：1  

李宏  莫放  Jerry Stuth 《中国畜牧杂志》2004,40(6):22-24

利用近红外光谱法 (NIRS)对绵羊粪便的扫描值和日粮的体内测定值来建立定标方程式。以绵羊为试验动物 ,日粮主要由各种牧草、作物秸秆和棉花籽壳组成 ,试验动物日粮设计了 78个蛋白水平。在 2 0 0 2年和 2 0 0 3年分别用 15只和 2 0只成熟母羊 (体重为 5 5± 2 .4kg)进行了为期 7周的实验。体内收粪法测定出的日粮可消化有机物(DOM)水平为 5 2 .4 %至 75 .8% ,日粮的可消化有机物的定标方程式决定系数r2 =0 .80 ,定标标准误差SEC =1.5 1。随机选取 2 0 0 3年试验第 3周第 7d的 10个粪便样品利用可消化有机物定标方程预测其日粮的可消化有机物 ,其结果是决定系数r2 =0 .94 5 ,预测标准误差SEP =0 .5 5 2 ,斜率Slope =1.0 83,表明利用近红外光谱法 (NIRS)对粪便的扫描值可以有效预测绵羊日粮的可消化有机物  相似文献   

Use of two doses of cloprostenol in different intervals for estrus synchronization in hair sheep under tropical conditions     

de Carvalho Menezes de Almeida  Sheylla Foligno  Souza-Fabjan  Joanna Maria Gonçalves  Balaro  Mario Felipe Alvarez  Bragança  Gláucia Mota  Pinto  Pedro Henrique Nicolau  de Almeida  José Gabriel  Moura  Ana Beatriz Bossois  da Fonseca  Jeferson Ferreira  Brandão  Felipe Zandonadi 《Tropical animal health and production》2018,50(2):427-432

Tropical Animal Health and Production - This study evaluated the effect of two doses of prostaglandin at different intervals on reproductive parameters of crossbred ewes. In Experiment 1, 30 ewes...  相似文献