Evaluation of mono- and polyclonal antibody-based antigen detection immunoassays for diagnosis of Trypanosoma evansi infection in the dromedary camel.     

O Diall  V M Nantulya  A G Luckins  B Diarra  B Kouyate 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1992,45(2):149-153

Two enzyme-linked immunosorbent assays (ELISA), one based on a mouse anti-Trypanosoma brucei group-specific monoclonal antibody and the other on rabbit anti-Trypanosoma evansi polyclonal antibodies, have been evaluated for their ability to detect circulating trypanosome antigens in camel sera as a means for the diagnosis of T. evansi infections. All 91 sera from a negative control camel herd from Kenya gave negative antigen-ELISA results in the monoclonal antibody-based ELISA and only 2 of them (2.2%) gave false positive results in the polyclonal antibody-based ELISA. In subsequent analyses of sera from infected camels (as determined by mouse inoculation), the monoclonal antibody-based ELISA detected antigens in 90 (83.3%) out of the 108 sera tested. This percentage was lower for the polyclonal antibody-based ELISA which was able to detect antigens in 67 (60.9%) out of the 110 sera tested. The two tests detected probably different antigens and when the results were combined, 99 out of 107 (92.5%) sera were shown to be ELISA positive. In a survey involving 316 camels from the Gao and Nara areas, in Mali, a high proportion of animals tested were antigen positive (43.5 and 42.9%, respectively for the mono- and polyclonal antibody-based ELISA) compared to only 22 (7.0%) diagnosed by the parasite detection techniques. Thus, these immunoassays were at least six times more sensitive than the haematocrit centrifugation technique. As a large proportion of cases may be antigen positive but parasite negative, these two of "surra" immunoassays should be used in routine diagnosis in addition to the parasite detection techniques in the dromedary camel.  相似文献   

Market‐led options to scale up legume seeds in developing countries: Experiences from the Tropical Legumes Project     

Jean‐Claude Rubyogo  Essegbemon Akpo  Lucky Omoigui  Gaur Pooran  Sushil Kumar Chaturvedi  Asnake Fikre  Desmae Haile  Ajeigbe Hakeem  Emmanuel Monyo  Stanley Nkalubo  Berhanu Fenta  Papias Binagwa  Michael Kilango  Magdalena Williams  Omari Mponda  David Okello  Mekasha Chichaybelu  Amos Miningou  Joseph Bationo  Dramane Sako  Zoumana Kouyate  Sory Diallo  Richard Oteng‐Frimpong  Julius Yirzagla  Teryima Iorlamen  Umar Garba  Haruna Mohammed  Chris Ojiewo  Alpha Kamara  Rajeev Varshney  Shyam Narayan Nigam  Pasupuleti Janila  Hajisaheb Lalasab Nadaf  Sylvia Kalemera 《Plant Breeding》2019,138(4):474-486

There are several hurdles to ensure sustainable seed production and consistent flow of improved legume varieties in sub‐Saharan Africa (SSA) and South Asia (SA). The unreliable demand, autogamous nature of most of the grain legumes, and slow variety replacement rate by smallholder farmers do not provide strong incentive for private seed companies to invest in legume seed business. Unless a well thought‐out and comprehensive approach to legume seed delivery is developed, current seed shortages will continue, eroding emerging market opportunities. The experiences reported here are collated through a 10‐year partnership project, the Tropical Legumes in SSA and SA. It fostered innovative public–private partnerships in joint testing of innovative market‐led seed systems, skills and knowledge enhancement, de‐risking private sector initiatives that introduced in new approaches and previously overlooked entities in technology delivery. As new public and private seed companies, individual seed entrepreneurs and farmer organizations emerged, the existing ones enhanced their capacities. This resulted in significant rise in production, availability and accessibility of various seed grades of newly improved and farmer demanded legume varieties in the target countries.  相似文献