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171.
172.
Iron oxides in two Oxisols from the Brazilian coastal plain 总被引:1,自引:0,他引:1
J. D. FABRIS M. RESENDE E. GALVAO DA SILVA J. M. D. COEY 《European Journal of Soil Science》1985,36(4):543-550
Two Oxisols from the B2 horizon at similar locations 2 km apart on the Brazilian coastal plain with a udic, isohyperthermic regime were practically identical in chemical composition but differed markedly in colour; one was a dark reddish brown, the other a pale ochre. Mossbauer spectra at 295 K, 80 K and 4.2 K indicated a clear difference in iron oxide mineralogy. Iron was present as aluminous hematite and goethite, with Al substitutions of approximately 20% in the two phases. However, the relative proportion of iron present in hematite and goethite was 45:55 in the first sample and 12:88 in the second. Possible reasons for these differences are discussed. 相似文献
173.
W O James W O Williams J C Prucha R Johnston W Christensen 《Journal of the American Veterinary Medical Association》1992,200(1):57-59
The USDA Food Safety and Inspection Service determined populations of bacteria on poultry during processing at a slaughter plant in Puerto Rico in November and December 1987. The plant was selected because of its management's willingness to support important changes in equipment and processing procedures. The plant was representative of modern slaughter facilities. Eight-hundred samples were collected over 20 consecutive 8-hour days of operation from 5 sites in the processing plant. Results indicated that slaughter, dressing, and chilling practices significantly decreased the bacterial contamination on poultry carcasses, as determined by counts of aerobic bacteria, Enterobacteriaceae, and Escherichia coli. Salmonella was not enumerated; rather, it was determined to be present or absent by culturing almost the entire rinse. The prevalence of Salmonella in the study decreased during evisceration, then increased during immersion chilling. 相似文献
174.
Christensen NH 《New Zealand veterinary journal》1988,36(2):82-85
In a flock of 17000 broilers, characteristic Marek's disease (MD) paralysis, accompanied by increased mortality occurred during the fourth week of the flock's life. Cytolytic lesions and atrophy in the bursae of Fabricius, and the severity of lymphocytic infiltration of nerves, livers, proventriculus and brain are suggestive of the involvement of MD virus of greater pathogenicity than has been encountered previously in New Zealand. 相似文献
175.
Ahmadpour Amir Christensen Rachael G. Zarrin Mousa Farjood Farhad Ahmadpour Ahmadali 《Tropical animal health and production》2019,51(6):1651-1660
Tropical Animal Health and Production - Based on current knowledge, C16 and C18 fatty acids (FA) are considered the most functional FA in hepatic metabolism. Although these FAs have been... 相似文献
176.
177.
Maria Anete LALLO Lidiana Flora VIDOTO DA COSTA Anuska Marcelino ALVARES-SARAIVA Paulo Ricardo Dell’Armelina ROCHA Diva Denelle SPADACCI-MORENA Fabiana Toshie de Camargo KONNO Ivana Barbosa SUFFREDINI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):171-176
178.
农业产业集群是推动农村经济发展的重要产业组织形式。现以新疆为研究对象,从新疆农业产业集群的发展优势和现状出发,结合区位商进行分析,发现当前新疆农业产业集群主要面临产业链条短、市场需求反应慢、支持服务体系不健全等问题,最后从产业链、科技投入、市场需求和网络体系等角度提出新疆农业产业集群发展的对策。 相似文献
179.
A reovirus was isolated from a flock of 12,000 broiler chickens which experienced a total mortality of 6.3% up to 35 days. The reovirus produced large syncytia in primary chicken kidney cell cultures with eosinophilic intracytoplasmic inclusion body formation. Infected cells reacted with fluorescein conjugated specific anti-reovirus serum. Negatively strained virions had a double shelled appearance with overall diameter of 65 to 70 nm. The nucleic acid had ten discrete segments with electrophoretic mobilities as would be expected for a reovirus. 相似文献
180.
Gooneratne SR Olkowski AA Klemmer RG Kessler GA Christensen DA 《The Canadian veterinary journal. La revue veterinaire canadienne》1989,30(2):139-146
Following development of polioencephalomalacia in one of 105 cattle in a farm in southeastern Saskatchewan, a study was initiated to monitor thiamine (B1) and copper (Cu) status, and to evaluate interactive nutritional factors which may have been responsible for this occurrence. It was evident that a combination of high sulfur (S) and low Cu intake was responsible for the depletion of blood B1 and plasma Cu. Supplementation with trace minerals alone resulted in a significant (p<0.05) improvement in both B1 and Cu status of the herd. We recommend that herds exposed to high intakes of S be supplemented with Cu up to 50 mg/kg feed dry matter to alleviate potential deficiencies of B1 and Cu. 相似文献