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81.
The diagnosis of subclinical paratuberculosis is still considered a major problem worldwide. As part of investigating diagnostic strategies for the paratuberculosis infection, sequential results of various diagnostic methods in a progressive experimental infection in goats were evaluated. Twenty-three goat kids were divided into three groups: the infected, contact and control, comprising 10, five and eight goats respectively. Animals of the infected group were orally inoculated on seven occasions with 5 ml of inoculum containing 2 x 10(9)Mycobacterium avium ssp. paratuberculosis per ml. Lymphoycte proliferation test using johnin PPD detected paratuberculosis infection from 60 days post-infection (DPI) onwards. The johnin PPD was found to be a better antigen for the proliferative assays as compared with the sonicated antigen. The faecal smear examination with acid-fast staining detected more goats as positive than bacterial culture and polymerase chain reaction (PCR). Lipoarabinomannan enzyme-linked immunosorbent assay (ELISA) started detecting infected goats from 150 DPI onwards followed by indirect ELISA and agar gel immunodiffusion from 180 DPI onwards. Histological examination was confirmatory and detected five infected goats as positive.  相似文献   
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The temporal phenology of leaf bud bursting, leaf initiation, leaf maturation, leaf fall, flower initiation, fruit initiation and fruit fall was recorded for eight tree species (Ficus hispida, F. squamosa, Mallotus nudiflorus, M. philippensis, Shorea robusta, Schleichera oleosa, Pongamia pinnata and Terminalia arjuna) in the tropical moist deciduous forest of Himalayan Terai region from November 2009 to October 2012. The study revealed that a short low temperature dry period, sufficient winter rain and temperature rise are the triggering factors for summer leaf flushing and, the increased soil water availability for second leaf flushing in rains. Initiation of flowering with leaf emergence in the dry period supports higher rate of fruit setting due to maximum availability and activities of pollinators. The dispersal and post dispersal success of fruits increased by their ripening before and/or in the rainy season. In T. arjuna, no correlation has been found between the fruiting and rains. M. nudiflorus and M. philippensis initiate leaves and flowers with the first significant increase in temperature and photoperiod and are thus suggested as the potential tree species for climate change studies in tropics.  相似文献   
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