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201.
Manasse HR 《Science (New York, N.Y.)》2005,308(5728):1558-1559
202.
Evelyn Madoroba Edilbert Van Driessche Henri De Greve Jan Mast Ignatious Ncube John Read Sonia Beeckmans 《Tropical animal health and production》2009,41(7):1539-1547
World-wide, enterotoxigenic Escherichia coli (ETEC) and verotoxigenic E. coli (VTEC)-induced diarrhea are economically important for porcine producers. Our aim was to investigate the prevalence of toxin
and fimbrial genes among E. coli isolated from diarrheic piglets from randomly selected piggeries in Zimbabwe.We used multiplex PCR for screening STa, STb,
LT, and Stx-2e toxins. Subsequently F4, F5, F6, F18 and F41 fimbriae genes were screened in toxin positive isolates. Toxin
positive strains lacking tested fimbriae genes were characterized using transmission electron microscopy, agglutination and
agglutination inhibition tests. Approximately 32% of the 1,984 isolates tested positive for STa, STb, LT or Stx-2e genes.
Of these, approximately 81% had F4, F5, F6, F18 or F41 fimbriae genes. The remaining toxin positive strains lacked tested
fimbriae genes and appeared to either express F1-like fimbriae, or lacked fimbriae. The data constitute an important framework
for implementation of prevention measures, such as using relevant fimbriae-based vaccines against ETEC induced diarrhea or
VTEC-induced edema. 相似文献
203.
Sbastien Assi Nathalie Bareille Franois Beaudeau Henri Seegers 《Preventive veterinary medicine》2009,91(2-4):218-225
Our aim was to determine at calf-batch level the management- and housing-related risk factors of respiratory disorders in non-weaned Charolais calves. Farmers recorded cases according to the definition provided i.e. the association of at least one respiratory sign and, in the same calf or another calf of the same batch, at least one general sign on the same day or the day before. During farm visits, quality of farmers’ records was checked and questionnaires were applied to gather farm and herd characteristics and to describe farming practices and housing facilities. Data were suitable for analysis for 172 batches where no metaphylactic treatment was implemented. Batches had great disparity in incidence of respiratory disorders. In the 120 batches with at least one case, the quartiles of incidence rate were, respectively, 0.95, 2.15 and 3.59 cases per 1000 calf-days at-risk. For risk-factor analysis, the statistical unit was the calf-batch located in a given batch. We used a ZINB model because (i) there was significant overdispersion of incidence rates of respiratory disorders (overdispersion test statistic of O = 1049 (P < 0.001)), (ii) probability was high that a two-group modelling process existed (Vuong statistic of V = 2.44 (P = 0.0073)) and (iii) the ZINB model fit significantly better than the ZIP model (likelihood-ratio statistic of 340.14 (P < 0.001)). The risk was higher in open-fronted barns or in open barns compared to closed ones (incidence-rate ratios (IRRs): 1.9 and 1.8), in barns where no annual disinfection was implemented (IRR: 1.5) and in part slope with straw/part scraped and in part straw-bedded/part scraped barns compared to completely straw-bedded barns (IRRs: 1.9 and 1.6). Larger calf-batches were more at-risk than smaller batches (OR for the effect of an increase of 10 calves on the probability of a 0 count: 0.5). 相似文献
204.
Riss J Décordé K Sutra T Delage M Baccou JC Jouy N Brune JP Oréal H Cristol JP Rouanet JM 《Journal of agricultural and food chemistry》2007,55(19):7962-7967
The effects of spirulina and its chromophore phycocyanin, both without bound Se or selenium-enriched, were studied on plasma cholesterol, early atherosclerosis, cardiac production of superoxide anions, and NAD(P)H oxidase expression in hamsters. Forty hamsters were divided into 5 groups of 8 and fed an atherogenic diet for 12 weeks. They received by gavage either 7.14 mL/(kg day) phycocyanin (PC), Se-rich phycocyanin (SePC), spirulina (SP) or Se-rich spirulina (SeSP) in water, or water as control. SeSP and SePC supplied 0.4 microg of Se per 100 g body weight. Plasma cholesterol and non-HDL cholesterol concentrations were lower in group consuming SePC. HDL-cholesterol was never affected. SePC significantly increased plasma antioxidant capacity by 42% compared with controls. A sparing effect in liver glutathione peroxidase (87% on average) and superoxide dismutase (56% on average) activity was observed for all the groups compared to controls. Aortic fatty streak area was significantly reduced in the experimental groups, especially by PC (82%) and SePC (85%). Cardiac production of superoxide anion significantly decreased by approximately 46-76% in the four experimental groups and especially in SePC group (76%). The expression of p22phox subunit of NAD(P)H oxidase decreased by 34% after consumption of SePC. The results indicate that chronic consumption of Se-rich spirulina phycocyanin powerfully prevents the development of atherosclerosis. The underlying mechanism is related mainly to inhibiting pro-oxidant factors and at a lesser extent improving the serum lipid profile. 相似文献
205.