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71.
72.
P. Jennings † M. E. Coates J. A. Turner E. A. Chandler P. Nicholson 《Plant pathology》2004,53(2):182-190
Functioning Tri13 and Tri7 genes are required for the production of nivalenol and 4-acetyl nivalenol, respectively, in Fusarium species producing type B trichothecenes. Mutations have been identified in isolates which are able to produce deoxynivalenol (DON) but unable to convert this to nivalenol (NIV). In such isolates of Fusarium culmorum , the Tri7 gene is deleted entirely. PCR assays specific for functional and nonfunctional/deleted versions of Tri7 and Tri13 were used to determine the ability of 153 single spore isolates of F. culmorum to produce the 8-ketotrichothecenes deoxynivalenol and nivalenol. The isolates were collected from 76 different locations across England and Wales between 1994 and 2002. Four isolates were also obtained from one field in Scotland. Both DON and NIV chemotypes of F. culmorum were identified, with DON chemotypes predominating overall. In addition, all DON chemotypes were shown to produce 3-acetyl DON using primer sets developed to Tri3 . From fields where more than one F. culmorum isolate was obtained, isolates were not exclusively of a single chemotype. Differences in the distribution of DON and NIV chemotypes were identified, with a greater proportion of NIV chemotypes present in the south and west of England and Wales, whereas a greater proportion of DON chemotypes were found in the north and east of England. Seasonal differences in the ratio of DON:NIV chemotypes were indicated. However, these were related to seasonal variation in the distribution of F. culmorum . 相似文献
73.
Juvenal Kanani Dirk Philipp Kenneth P Coffey Elizabeth B Kegley Charles P West Shane Gadberry John Jennings Ashley N Young Robert T Rhein 《畜牧与生物技术杂志(英文版)》2014,5(1):1-8
Camelina sativa is an oil seed crop which can be grown on marginal lands. Camelina seed oil is rich in omega-3 fatty acids (>35%) and γ-tocopherol but is also high in erucic acid and glucosinolates. Camelina meal, is the by-product after the oil has been extracted. Camelina meal was fed to 28 d old weaned pigs at 3.7% and 7.4% until age 56 d. The camelina meal supplements in the soy based diets, improved feed efficiency but also significantly increased the liver weights. Gene expression analyses of the livers, using intra-species microarrays, identified increased expression of phase 1 and phase 2 drug metabolism enzymes. The porcine versions of the enzymes were confirmed by real time PCR. Cytochrome 8b1 (CYP8B1), aldehyde dehydrogenase 2 (Aldh2), and thiosulfate transferase (TST) were all significantly stimulated. Collectively, these genes implicate the camelina glucosinolate metabolite, methyl-sulfinyldecyl isothiocyanate, as the main xeniobiotic, causing increased hepatic metabolism and increased liver weight. 相似文献
74.
In vitro Development of Buffalo Oocytes in Media-containing Fluids from Different Size Class Follicles 总被引:1,自引:0,他引:1
S Nandi HM Raghu BM Ravindranatha PSP Gupta PV Sarma 《Reproduction in domestic animals》2004,39(1):33-38
Studies were conducted to investigate the effect of supplementation of fluid from different sized class [small (SFF, < 3 mm), medium (MFF, 3-8 mm) and large (LFF, > 8 mm)] of normal and cystic (CFF) ovarian follicles in oocyte culture media on oocyte maturation rate and embryo development in vitro and to test the efficacy of follicular fluid (FF) from different size classes as a whole oocyte maturation medium. Results suggested that FF were capable of developing buffalo oocytes to embryonic stage in vitro although its efficacy was lower than that of serum. Regardless of high maturation rates after in vitro maturation (IVM) in media containing FF or IVM in whole FF, low blastocyst rates were obtained after in vitro fertilization (IVF) and culture of embryos. Follicular fluid from small follicles had significantly (p < 0.05) higher potential of developing buffalo oocytes to embryonic stage in vitro than that from medium and large follicles. Cystic FF was not capable of supporting development of buffalo oocytes in vitro. 相似文献
75.
P A Jennings 《Research in veterinary science》1979,26(1):111-113
Calves, sensitised by cutaneous application of dinitrochlorobenzene, developed lesions of delayed hypersensitivity at the sites of application nine to 14 days later. Leucocytes from sensitised calves, collected 10 to 16 days after sensitisation, reacted in an in vitro leucocyte adherence inhibition test with the same hapten in water soluble form, dinitrobenzenesulphonate. The leucocyte adherence inhibition microtest which was simple, rapid, reproducible and amenable to rigorous statistical analysis, should find use in many areas of bovine immunology. 相似文献
76.
Jennings GB 《Journal of veterinary medical education》2006,33(3):419-421
The US Agency for International Development (USAID) works within the overall purpose of US foreign assistance to improve the lives of the citizens of the developing world. Through partnerships with other agencies, organizations, and governments, and using its field offices around the world, USAID strives to develop local capacity and thus build sustainable development. Two specific USAID programs pertinent to veterinary medicine are global health and agriculture. In the area of global health, veterinarians can aid USAID's work to improve the quality, availability, and use of essential health services that specifically target maternal and child health, HIV/AIDS, family planning and reproductive health, infectious diseases, environmental health, nutrition, and other life-saving areas. The challenge of making the agricultural sector in a developing country more productive is a critical one for USAID and a clear area for input from the veterinary profession. Animal agriculture is the largest single sector of agricultural economies in most developing countries, and livestock remains a critical component of poverty alleviation. There are educational requirements that benefit anyone working at USAID and can be met prior to admittance to a DVM program, as part of a DVM curriculum, or in post-graduate training/employment, such as proficiency in a foreign language; environmental sciences background; familiarity with accounting and management techniques; expertise in foreign animal diseases, zoonotic diseases, epidemiology, food safety, and nutrition, as well as the application to human health of those areas; an advanced degree such as an MPH; and management experience. Appropriately trained veterinarians can make enormous contributions to USAID's global efforts to improve the health and agriculture sectors of developing nations. 相似文献
77.
Reuter DC Simon-Miller AA Lunsford A Baines KH Cheng AF Jennings DE Olkin CB Spencer JR Stern SA Weaver HA Young LA 《Science (New York, N.Y.)》2007,318(5848):223-225
Several observations of Jupiter's atmosphere made by instruments on the New Horizons spacecraft have implications for the stability and dynamics of Jupiter's weather layer. Mesoscale waves, first seen by Voyager, have been observed at a spatial resolution of 11 to 45 kilometers. These waves have a 300-kilometer wavelength and phase velocities greater than the local zonal flow by 100 meters per second, much higher than predicted by models. Additionally, infrared spectral measurements over five successive Jupiter rotations at spatial resolutions of 200 to 140 kilometers have shown the development of transient ammonia ice clouds (lifetimes of 40 hours or less) in regions of strong atmospheric upwelling. Both of these phenomena serve as probes of atmospheric dynamics below the visible cloud tops. 相似文献
78.
79.
80.
Juliana K. Buckelew Wayne E. Mitchem David W. Monks Katie M. Jennings Lucky K. Mehra 《International Journal of Fruit Science》2019,19(1):75-90
Field experiments were conducted at two locations (Clayton and Jackson Springs, NC) to determine the influence of vegetation-free strip width (VFSW) and irrigation on newly planted peach growth and yield in a low-density orchard with a volunteer weedy ground cover. The experiments included VFSW of 0, 0.6, 1.2, 2.4, 3, or 3.6 m under irrigated or nonirrigated conditions. Seasonal variation in the orchard floor vegetation was observed as different weed species reported in summer and winter. However, this difference was not apparent with respect to VFSF and irrigation. At Jackson Springs, NC, the predicted irrigated VFSW which would produce the same trunk cross-sectional area (TCSA) as the grower standard (3-m nonirrigated) was 1.5, 1.3, and 0.8 m for one-, two-, and three-year-old trees, respectively. The predicted irrigated VFSW which would produce the same yield as the grower standard was 1.16 m. At Clayton, TCSA and fruit yield were not different by irrigation, but did increase linearly with VFSW. At both locations, leaf nitrogen (N) concentration was lower in irrigated trees than nonirrigated trees. Leaf N, leaf area, and SPAD were positively related to VFSW at Jackson Springs. In contrast, leaf N concentration was not different by VFSW at Clayton. However, leaf area and SPAD were positively related to VFSW at Clayton. These results suggest that a 1.5 m VFSW combined with proper irrigation and fertilization will produce tree growth and yield in newly planted orchard with volunteer weedy vegetation similar to the current grower standard in the southeastern USA. 相似文献