Johne's disease in Canada Part I: clinical symptoms, pathophysiology, diagnosis, and prevalence in dairy herds     

Tiwari A  VanLeeuwen JA  McKenna SL  Keefe GP  Barkema HW 《The Canadian veterinary journal. La revue veterinaire canadienne》2006,47(9):874-882

Recent international developments in the area of infectious disease control and nontariff trade barriers, along with possible zoonotic concerns, have provoked a revival of interest in Johne's disease in Canada and elsewhere. The bacterium causing Johne's disease, Mycobacterium avium subspecies paratuberculosis, is distributed worldwide and causes chronic granulomatous enteritis, also known as paratuberculosis, in domestic and exotic ruminants, including cattle. The subclinical form of this disease results in progressive weight loss, reduced milk production, lower slaughter value, and premature culling, with possible impacts on fertility and udder health. Eventually, infection can lead to the clinical form that manifests as chronic diarrhea, emaciation, debilitation, and eventual death. Currently, available tests to detect infected animals produce many false-negative results and some false-positives, particularly in subclinically infected animals, thus making their interpretation and utilization challenging in control programs. The objective of this 2-part review is to critically review the literature about Johne's disease in dairy cattle for bovine practitioners in Canada. Part I covers the clinical stages, pathophysiology, diagnosis, and prevalence of infection in Canada, while Part II discusses impacts, risk factors, and control programs relevant to Canadian dairy farms. By reviewing the scientific literature about Johne's disease, control of the disease could be pursued through informed implementation of rational biosecurity efforts and the strategic use of testing and culling.  相似文献   

Alkaloids as potential anti-tubercular agents     

Navneet Kishore  Bhuwan B. MishraVyasji Tripathi  Vinod K. Tiwari 《Fitoterapia》2009

An increasing incidence of deaths due to tuberculosis and the known drawbacks of the current existing drugs including the emergence of multi drug-resistant strains have led to a renewed interest in the discovery of new anti-tubercular agents with novel modes of actions. The recent researches focused on natural products have shown a useful way to obtain a potentially rich source of drug candidates, where alkaloids have been found more effective. The present review focuses on current epidemiology of tuberculosis, synergy of the disease with HIV, current therapy, available molecular targets and, highlights why natural products especially alkaloids are so important. The review summarizes alkaloids found active against mycobacteria from the mid-1980s to late 2008 with special attention on the study of structure–activity relationship (SAR).  相似文献   

Identification and characterization of two phytoplasma subgroups (16SrXI-D and 16SrXIV-A) associated with lychee (Litchi chinensis Sonn) in India     

Rao  Govind P.  Tiwari  Ajay K.  Madhupriya  Dubey  Durgesh 《植物病害和植物保护杂志》2017,124(3):235-239

Journal of Plant Diseases and Protection - Leaf rolling, necrosis and apical bud proliferation symptoms were recorded on lychee plants at Bhatpar Rani (Deoria district) and Gorakhpur (Gorakhpur...  相似文献   

利用卫星遥感和GIS技术测定印度切蒂斯格尔地区干旱热带森林的土地利用、生物量和碳贮量   总被引：1，自引：0，他引：1  

Arvind Bijalwan  S.L.Swamy  Chandra Mohan Sharma  Neeraj Kumar Sharma  A.K.Tiwari 《林业研究》2010,21(2):161-170

2001-2002年间,利用卫星遥感和GIS技术研究印度切蒂斯格尔邦的赖布尔地区干旱热带森林的土地利用、生物量和碳贮量情况。主要森林类型为:柚木森林、混合林、衰退森林和婆罗双树混交林。在这些不同森林类型中,立地的坡度和坡面影响森林植被类型、生物量和碳贮量。不同森林类型中,木材积蓄积量、生物量和碳贮量的变化范围分别为:35.59～64.31 m3·hm-2、45.94～78.31Mg·hm-2和22.97～33.27Mg·hm-2。混合林中每公顷的木材蓄积量、生物量和碳贮量最大,衰退森林中的最低。混合林、柚木森林、衰退森林和婆罗双树混交林的总碳量分别为8170.72 Mg、81656.91 Mg、7833.23 Mg和7470.45 Mg。蒂斯格尔邦地区干旱热带森林处于不成熟的生长阶段,且具有很强的碳回收潜力。图6表7参49。  相似文献   

A novel antifungal anthraquinone from seeds of Aegle marmelos Correa (family Rutaceae)     

Bhuwan B. Mishra  Navneet Kishore  Vinod K. Tiwari  Desh D. Singh  Vyasji Tripathi 《Fitoterapia》2010

A new anthraquinone, 1-methyl-2-(3′-methyl-but-2′-enyloxy)-anthraquinone (1) has been isolated from seeds of Aegle marmelos Correa and was characterized on the basis of spectral analysis (UV, IR, ¹H NMR, ¹³C NMR, 2D NMR and mass spectroscopy). The compound exhibited significant antifungal activity against pathogenic strains of Aspergillus species and Candida albicans in disc diffusion assay (MIC value of 6.25 μg/disc), microbroth dilution and percent spore germination inhibition assays (MIC value of 31.25–62.5 μg/ml).  相似文献   

Surveillance of equine respiratory viruses in Ontario     

Diaz-Mendez A  Viel L  Hewson J  Doig P  Carman S  Chambers T  Tiwari A  Dewey C 《Canadian journal of veterinary research》2010,74(4):271-278

The objective of this project was to develop and implement an active surveillance program for the early and rapid detection of equine influenza viruses in Ontario. For this purpose, from October 2003 to October 2005, nasopharyngeal swabs and acute and convalescent serum samples were collected from 115 client-owned horses in 23 outbreaks of respiratory disease in Ontario. Sera were paired and tested for antibody to equine influenza 1 (AE1-H7N7), equine influenza 2 (AE2-H3N8), equine herpesvirus 1 and 4 (EHV1 and EHV4), and equine rhinitis A and B (ERAV and ERBV). Overall, the cause-specific morbidity rate of equine influenza virus in the respiratory outbreaks was 56.5% as determined by the single radial hemolysis (SRH) test. The AE2-H3N8 was isolated from 15 horses in 5 outbreaks. A 4-fold increase in antibody levels or the presence of a high titer against ERAV or ERBV was observed in 10 out of 13 outbreaks in which AE2-H3N8 was diagnosed as the primary cause of disease. In conclusion, AE2-H3N8 was found to be an important contributor to equine respiratory viral disease. Equine rhinitis A and B (ERAV and ERBV) represented an important component in the equine respiratory disease of performing horses.  相似文献   

Detection of <Emphasis Type="Italic">Ageratum enation virus</Emphasis> from cat’s whiskers (<Emphasis Type="Italic">Cleome gynandra</Emphasis> L.) with leaf curl symptoms in India     

S. K. Raj  S. K. Snehi  M. S. Khan  A. K. Tiwari  G. P. Rao 《Journal of General Plant Pathology》2010,76(4):292-294

An association of a begomovirus with leaf curl symptoms on Cleome gynandra was detected using a polymerase chain reaction (PCR) with begomovirus-specific primers. Further, the complete DNA-A of the begomovirus was cloned and sequenced. BLAST analysis of the sequence data revealed 92–99% identities and close relationships with several isolates of Ageratum enation virus (AgEV); therefore, we identified the virus associated with leaf curl symptoms of C. gynandra as an isolate of AgEV. This report is the first on the detection of AgEV in plants of C. gynandra with leaf curl in India.  相似文献   

Sonicator dyeing of modified cotton, wool and silk with Mahonia napaulensis DC. and identification of the colorant in Mahonia     

Padma S. Vankar  Rakhi Shanker  Shalini Dixit  Debajit Mahanta  S.C. Tiwari 《Industrial Crops and Products》2008,27(3):371-379

Mahonia napaulensis DC. (local name—Taming) family Berberidaceae, produces natural dye from its stem which has been used for dyeing textiles by the Apatanis (a tribe of Arunachal Pradesh) since ancient times. Sonicator dyeing with Mahonia napaulensis showed marked improvement in dye uptake. It showed that pretreatment with metal mordant (2%, w/w with respect to the fabric) improved substantially the fastness properties for dyed cotton, silk fabrics and wool yarn. Five fractions were isolated from column chromatography of the stem extract of Mahonia. Attempts have been made to identify these fractions by matching the spectral data which indicated that they were from a well-known isoquinoline alkaloid family.  相似文献   

Sonicator dyeing of natural polymers with <Emphasis Type="Italic">Symplocos spicata</Emphasis> by metal chelation     

Padma S. Vankar  Rakhi Shanker  Shalini Dixit  Debajit Mahanta  S. C. Tiwari 《Fibers and Polymers》2008,9(2):121-127

Symplocos spicata (local name: Dom sheng) belonging to Family Symplococeae produces yellowish brown natural dye which has been used for dyeing textiles since ancient times by the Monpas tribe of Arunachal Pradesh. Symplocos spicata (Dom Sheng) was found in the Lumla area of Tawang district. Leaves of the plant are used by the Monpas and Tibetans for extraction of dye. Innovative sonicator dyeing with S. spicata showed that pretreatment with 2–4% metal mordant of the weight of the fabric is optimum showing very good fastness properties for dyed natural polymers such as cotton, wool, and silk. CIELab and K/S of the dyed fabrics were also evaluated. The superiority of sonicator dyeing over conventional dyeing has been established through this study.  相似文献   

Effects on Lipid Oxidation and Bioactive Properties of Rainbow Trout Fillets Fed with Barley     

Julia Pinedo-Gil  Ana Tomás-Vidal  Daniel Rico  Brijesh Tiwari  Carlos Álvarez García  Miguel Jover-Cerdá 《Journal Of Aquatic Food Product Technology》2019,28(5):495-504

Barley concentrations ranging from 0% to 32% were incorporated into rainbow trout (Oncorhynchus mykiss) diets. The effect of barley concentration on lipid peroxidation and antioxidant activity of fish fillets were analyzed. Results showed that the inclusion of barley in rainbow trout diets had an inhibitory effect on lipid oxidation, probably associated with certain bioactive compounds in barley that could interact with scavenging and reducing metabolites involved in lipid oxidation. Concentrations up to 8% of barley produced fish fillets with high antioxidant activity and higher levels of alpha-tocopherol.  相似文献