Measurement of nitrate leaching losses from arable plots under different nitrogen input regimes     

A.J.A. Vinten  R.S. Howard  M.H. Redman 《Soil Use and Management》1991,7(1):3-13

Abstract. Leaching losses of nitrate-nitrogen were measured from a set of eight hydrologically isolated plots on a clay loam soil over the period from September 1987 to February 1990. Variable drainflow recovery from the plots hampered accurate estimation of nitrate loading, but results suggest that, when inorganic nitrogen fertilizer is applied up to the recommended amount, there is little influence of the amount applied on the amount leached. We did, however, observe the following effects on nitrate leaching: leguminous green manure incorporated in autumn increased leaching of nitrate-nitrogen by 10–15 kg per hectare during the winter; autumn cultivation caused some increase in leaching compared with no cultivation in one year; some systematic variations in nitrate leaching occurred between years and between plots, but were unrelated to treatments.
From the results we conclude that green manuring does not provide sufficient nitrogen for organically grown crops on this soil but contributes significantly to nitrate leaching, and that growing spring cereals, with the land remaining in stubble as long as possible in autumn, may be the best strategy to minimize nitrate leaching.  相似文献   

Glycerol Tolerance of IHHN Virus of Penaeid Shrimp   总被引：1，自引：0，他引：1  

Donald V.  Lightner  Leone L.  Mohney  Rodney R.  Williams Rita M.  Redman 《Journal of the World Aquaculture Society》1987,18(3):196-197

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A virus in a fungus in a plant: three-way symbiosis required for thermal tolerance   总被引：2，自引：0，他引：2  

Márquez LM  Redman RS  Rodriguez RJ  Roossinck MJ 《Science (New York, N.Y.)》2007,315(5811):513-515

A mutualistic association between a fungal endophyte and a tropical panic grass allows both organisms to grow at high soil temperatures. We characterized a virus from this fungus that is involved in the mutualistic interaction. Fungal isolates cured of the virus are unable to confer heat tolerance, but heat tolerance is restored after the virus is reintroduced. The virus-infected fungus confers heat tolerance not only to its native monocot host but also to a eudicot host, which suggests that the underlying mechanism involves pathways conserved between these two groups of plants.  相似文献   

World protohistory     

Redman CL 《Science (New York, N.Y.)》1977,198(4313):183-184

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Winter dysentery in dairy herds: electron microscopic and serological evidence for an association with coronavirus infection.     

L J Saif  K V Brock  D R Redman  E M Kohler 《The Veterinary record》1991,128(19):447-449

Faeces and, or, paired sera were collected from cows in six dairy herds with classical winter dysentery. Similar samples were collected from cows in three other dairy herds experiencing non-haemorrhagic diarrhoea during the survey period. Coronavirus was the only enteric pathogen identified by immune electron microscopy (IEM) in all six outbreaks, occurring in 26 of 29 (90 per cent) of the affected cows and in one of 11 normal cows from the same herds. Nineteen of 26 affected cows (73 per cent) developed greater than four-fold increases in neutralising antibody titres to the Mebus strain of bovine coronavirus, compared with two of eight normal cows in the same herds. No cows showed greater than four-fold increases in antibody titres to bovine virus diarrhoea virus. None of the cows from the three herds with non-haemorrhagic diarrhoea shed coronavirus in faeces detectable by IEM or developed greater than two-fold rises in coronavirus antibody titres in paired sera. No enteric pathogens were identified in two of the herds. However, two cows in the third herd shed a group B rotavirus detected by IEM. These findings provide additional evidence for a possible role for bovine coronavirus in the aetiology of winter dysentery. Furthermore, this is the first report of a group B rotavirus associated with diarrhoea in adult cattle.  相似文献   

A breeding program for the establishment and maintenance of a stable gene pool in a Beagle dog colony to be utilized for long-term experiments   总被引：3，自引：0，他引：3  

S W Bielfelt  A J Wilson  H C Redman  R O McClellan  L S Rosenblatt 《American journal of veterinary research》1969,30(12):2221-2229

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Water quality,waste production,and off-flavor characterization in a depuration system stocked with market-size Atlantic salmon Salmo salar     

John Davidson  Natalie Redman  Curtis Crouse  Brian Vinci 《Journal of the World Aquaculture Society》2023,54(1):96-112

Land-based Atlantic salmon, Salmo salar, grow-out facilities utilize depuration to remediate off-flavor. Water used in this process is either discharged or repurposed as supply water in recirculating aquaculture systems (RAS). Both approaches require an understanding of water quality and waste production for water treatment decisions and compliance with pollution discharge standards; however, these data were lacking. Therefore, a study was carried out to characterize these parameters. To begin, 311 salmon (5–6 kg) originally cultured in freshwater RAS were stocked at 100 kg/m³ in an 18 m³ depuration tank. Feed was withheld 1 day before transfer and throughout the 7-day study period. Hours after stocking, total suspended solids (TSS), total phosphorus (TP), and total ammonia nitrogen (TAN) levels spiked, and concentrations declined thereafter. Delta TSS and TP were negligible by the end of the trial; however, TAN plateaued, indicating that salmon began to catabolize somatic tissue in the absence of feeding. Geosmin and 2-methylisoboreol levels in water and fish were low throughout the study. This research indicates that residual waste production occurs while depurating Atlantic salmon. Procedural refinements and recommendations were gleaned including locality for introducing depuration system water within RAS and extension of the feed withholding period before depuration.  相似文献   

Winter dysentery in adult dairy cattle: detection of coronavirus in the faeces   总被引：10，自引：0，他引：10  

L J Saif  D R Redman  K V Brock  E M Kohler  R A Heckert 《The Veterinary record》1988,123(11):300-301

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Identification by transfer blot of antigens reactive in the enzyme-linked immunosorbent assay (ELISA) in rabbits immunized and a calf infected with Cryptosporidium sp   总被引：5，自引：0，他引：5  

A Lazo  O O Barriga  D R Redman  S Bech-Nielsen 《Veterinary parasitology》1986,21(3):151-163

Soluble and particulate fractions of Cryptosporidium sp. oocysts from cattle were obtained by homogenization and sonication. Electrophoresis of the soluble fraction in polyacrylamide gels with sodium dodecyl sulfate and silver staining revealed the presence of 41 bands. Enzyme-linked immunosorbent assay (ELISA) of sera from rabbits immunized with either fraction and from a calf 40 days after infection showed that the animals produced specific antibodies. Enzyme-linked immunoelectrotransfer blot tests revealed the presence of five antigens with the rabbit sera and nine with the calf serum. ELISA proved to be an appropriate test for diagnosis of cryptosporidiosis. Selection of reactive antigens may improve the quality of diagnosis and/or reveal the presence of protective materials in the parasite.  相似文献   

Concurrent experimentally induced infection with Eimeria bovis and coronavirus in unweaned dairy calves.     

K H Hoblet  W P Shulaw  L J Saif  S E Weisbrode  S E Lance  R R Howard  E J Angrick  D R Redman 《American journal of veterinary research》1992,53(8):1400-1408

Over a period of 3 summers, 21 colostrum-fed Holstein bull calves, 1 to 3 days old, were assigned to 7 replicates, each consisting of 3 calves. Within each replicate of 3 calves, 2 were selected at random, to be given 100,000 to 146,000 sporulated coccidia oocysts (principally Eimeria bovis) orally 60 hours after arrival at the college research farm. On the thirteenth day after coccidia inoculation, 1 of the 2 calves that had been given coccidia and the third calf that had not been inoculated, were given coronavirus by intranasal and oral routes. Calves were observed daily, and consistency of feces was scored visually. Nasal swab specimens for indirect immunofluorescent antibody testing for coronavirus and fecal samples for oocyst determination were obtained approximately every third day. Of 7 calves that were given only coronavirus, 3 developed diarrhea of short duration. Of 7 calves that were given only coccidia oocysts, 6 developed diarrhea. All 7 calves inoculated initially with coccidia and subsequently with coronavirus developed diarrhea. For 5 of 7 replicates, calves that were given coccidia and coronavirus developed diarrhea first. When overall severity, measured by fecal score and by blood in the feces, was compared, calves inoculated with coccidia followed by coronavirus were more severely affected (P less than 0.05) than were calves that were given only coronavirus. Calves that were given only coccidia oocysts appeared more severely affected than calves that were given only coronavirus, but differences were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献