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991.
B. W. BEAVERS Z. LIU M. S. COX W. L. KINGERY G. E. BRINK P. D. GERARD K. C. MCGREGOR 《土壤圈》2010,20(2):217-288
An experiment arranged in a randomized complete block design with three replications was conducted on a Lexington soil (fine-silty, mixed, active, thermic, Ultic Hapludalfs) and a Loring soil (fine-silty, mixed, active, thermic, Oxyaquic Fragiudalfs) in Mississippi from September 1997 to September 2000 on 18 runoff plots under natural rainfall condition to study the phosphorus (P) dynamics in poultry litter amended soils under three management systems combining tillage and planting date treatments to identify effective management practices in southern U. S. A. The management systems in the study were:1) tillage in the fall prior to litter application followed by a delayed planting of fall forages (CT-DP); 2) tillage followed by immediate planting of the fall forage with subsequent litter application (CT-IP); and 3) no-till with planting prior to litter application (NT-IP). The results indicated that there was significant increase in soil P after 3 years of poultry litter application for both Lexington and Loring soils (P <0.05). Based on P budget analysis, the majority of P from poultry litter application (> 90%), was accumulated in both soils. In Loring soil, soluble P mass in the runoff was significantly higher from NT-IP than from CT-DP and CT-IP over the entire study period (P <0.01). For both soils, there were no significant differences in sediment P mass between management systems. For Loring soil, CT-DP and CT-IP were effective management practices to mitigate negative effects due to poultry litter application. 相似文献
992.
Polizopoulou ZS Kazakos G Georgiadis G Soubasis N Koutinas Ch Koutinas AF 《Journal of Feline Medicine and Surgery》2002,4(4):209-212
In this report two cases of localised tetanus in two young (<1 year) intact male and outdoor DSH cats, which had been missing, are described. Clinical examination revealed severe muscular spasms on the right (case 1) or both thoracic limbs (case 2). In the latter cat, wrinkling of the forehead and mild trismus were also seen. The routine diagnostic workup (CBC, survey radiographs of the spine, CSF analysis) did not reveal any abnormalities in both cats. EMG testing on the affected muscles in the second animal showed persistent spontaneous motor unit potentials, strongly indicating tetanus. The treatment, that was symptomatic (diazepam, metronidazole) and supportive (physical therapy, assist feeding and intravenous fluid therapy) resulted in the progressive improvement of limb rigidity and the restoration of motor dysfunction in a period of 5- (case 1) and 2- (case 2) month duration. 相似文献
993.
Dalimi A Motamedi G Hosseini M Mohammadian B Malaki H Ghamari Z Ghaffari Far F 《Veterinary parasitology》2002,105(2):161-171
In the present study, 115 stray dogs (56 males and 59 females, mixed breed), 86 golden jackal (Canis aureus, 42 males and 44 females), 60 red foxes (Vulpes vulpes, 33 males and 27 females), and three female wolves (Canis lupus) were examined for Echinococcus granulosus infection, as well as, 32,898 sheep, 10,691 goats, 15,779 cattle and 659 buffaloes for hydatid infection from five provinces in western Iran during 3 years (1997-2000). Meanwhile fertility rates of different types and forms of cysts isolated from infected animals and the viability of protoscolices were also determined. Results indicated that 19.1% of the dogs, 2.3% of the golden jackals and 5% of the red foxes were infected with Echinococcus granulosus. 11.1% of the sheep, 6.3% of the goats, 16.4% of the cattle and 12.4% of the buffaloes were also found to be infected with hydatid cyst. The cysts isolated from liver and lungs of the sheep show higher fertility rate than the cysts of liver and lungs of goats, cattle and buffaloes. 相似文献
994.
Z. Hedayatnasab R. Eslami-Farsani S. M. R. Khalili N. Soleimani 《Fibers and Polymers》2013,14(10):1650-1656
This paper focuses on the influence of temperature conditions and the clay contents on enhancement of mechanical characterization of polypropylene (PP) nanocomposites. The nanocomposites were prepared using the melt mixing technique in a co-rotating intermeshing twin screw extruder followed by injection moulding. Nanocomposites properties such as impact strength and ultimate tensile strength, yield strength, failure strain, Young’s modulus and toughness are calculated. The addition of clay to PP matrix was showed remarkable enhancement in mechanical properties at the temperature of 25 oC and 120 °C. Nearly 36 % and 160 % increase in the Young’s modulus and about 45 % and 62 % increase in the impact strength were observed at both room temperature (RT) and high temperature (HT), respectively. But, the tensile strength was not affected much. The basal spacing of clay in the composites was measured by X-ray diffraction (XRD). Scanning electron microscopy (SEM) was used to assess the surface morphology of the fractured surfaces and dispersion of the nanoclay. 相似文献
995.
Establishment of Protected Areas (PAs), in the face of rapid deforestation, forest degradation and climate change has been one of the key efforts in conservation of biodiversity worldwide in recent times. While Bangladesh has gained a degree of prominence in the world for its successful social forestry programs, the concept of collaborative protected area management is rather new in the country, initiated in 2004 by the Bangladesh Forest Department in five PAs with financial assistance from USAID. Based on empirical evidence from three of the pilot PAs, we examined the achievements and associated challenges and prospects for co-management. Our fieldwork revealed a number of challenges faced by co-management institutions: (1) institutions were dominated by the elite group, overshadowing the voice of the community people; (2) mutual trust and collective performance are key to good governance but had not taken root in the PAs; (3) encroachment onto forest land and subsequent conversion to agriculture remained a serious problem that discouraged forest-dependent people from participating actively in co-management initiatives; (4) legal provisions (including acts, rules and policies) were not clearly and adequately disseminated and understood at the community level; (5) there remained a degree of ambiguity regarding the roles and responsibilities of forest department (FD) and co-management committees (CMC) in field operations, and this was not enhancing transparency and accountability of the overall initiative; (6) the long-term sustainability of co-management institutions was another major concern, as the local intuitional structure was still in a nascent stage, and provisioning of resources (either internally or externally) remained somewhat uncertain. We offer recommendations for improvement. 相似文献
996.
Agrobacterium tumefaciens‐mediated transformation (ATMT) is being increasingly recognized as an effective insertional mutagenesis tool in studies of filamentous fungi for gene discovery and functional analysis. We developed and optimized ATMT for 2 Colletotrichum species, Colletotrichum gloeosporioides and Colletotrichum acutatum, the causative agents of Colletotrichum leaf disease in rubber trees in Southern China. A. tumefaciens strain AGL‐1 carrying an ILV1 gene and a green fluorescent protein gene were used to transform the conidia of these 2 Colletotrichum species. The transformation efficiency was correlated with the co‐cultivation duration and bacterial cell concentrations, which reached 300–400 transformants per 1 × 106 conidia after optimization. Southern blot analysis indicated that about 60.0% of the C. gloeosporioides transformants and 46.2% of the C. acutatum transformants had a single copy of T‐DNA in their genomes. Fungal genomic DNA segments flanking the T‐DNA were identified in the transformants through thermal asymmetrical interlaced polymerase chain reaction followed by sequencing. The flanking sequences from 4 C. acutatum and 7 C. gloeosporioides transformants showed moderate or weak homology to the NCBI database entries. Some sequences matching those reported virulence‐related genes. The results suggest that the T‐DNA inserted mutants banks constructed are useful for the discovery of new or important genes and to elucidate their function in the 2 Colletotrichum species. 相似文献
997.
F. YANG N. SUN Y. X. SUN Q. SHAN H. Y. ZHAO D. P. ZENG Z. L. ZENG 《Journal of veterinary pharmacology and therapeutics》2013,36(2):192-200
Yang, F., Sun, N., Sun, Y. X., Shan, Q., Zhao, H. Y., Zeng, D. P., Zeng, Z. L. A physiologically based pharmacokinetics model for florfenicol in crucian carp and oral‐to‐intramuscular extrapolation. J. vet. Pharmacol. Therap. 36 , 192–200. In this study, an oral physiologically based pharmacokinetics (PBPK) model was developed for florfenicol in crucian carp (Carassius auratus). Subsequently, oral‐to‐intramuscular extrapolation was performed and the two models were used to predict florfenicol concentrations in the edible tissues of crucian carp. The oral model gave good predictions in most tissues, except for kidney and liver in which the florfenicol concentrations were underestimated at the later time points. In contrast, using the intramuscular model, the concentrations in the kidney were overestimated at the later time points. Both models had the best predictive ability in the main edible tissue, the muscle. The oral model also accurately predicted the florfenicol concentrations in the muscle after multiple doses. The present study demonstrated the feasibility of predicting florfenicol concentrations in the edible tissues of crucian carp using a route‐to‐route extrapolation method. 相似文献
998.
Loreen Brehaut B.Sc. R.H. Jones B.Med.Sc. M.B. Ch.B. D.C.P. P.J. McEwan M.Sc. J.A.R. Miles M.A. M.D. F.R.A.C.P. P.R.S.N.Z. 《New Zealand veterinary journal》2013,61(5):82-86
Extract In Dunedin, feline respiratory infections with a high morbidity, but a low mortality except in very young animals, commonly occur in epizootics and appear to be enzootic between these outbreaks. The affected animals develop a serous ocular discharge which later becomes mucoid, and a mucoid nasal discharge associated with sneezing especially after handling. While these signs of infection are present, the animals are anorexic and listless. The disease may last for two weeks or more and sometimes affected cats develop a chronic snuffle lasting for months despite treatment. The disease is usually referred to as “snuffles”, although it is probably identical with the syndrome called “rhinotracheitis”. In the summer time, it commonly occurs in boarding establishments where large numbers of pets collected from a wide area are left by summer vacationers. In breeding catteries, infections occur most often in the spring and especially at the time of the first warm weather. Young kittens about 5 to 10 days old are usually affected but kittens which escape infection at this stage not infrequently develop symptoms at about 6 weeks of age. 相似文献
999.
B.W. Manktelow B.V.Sc. Ph.D. M.R.C.V.S. Dip.Microbiol. W.L. Porter B.V.M.S. M.R.C.V.S. N.Z. K.H.C. Lewis M.Agr.Sc. 《New Zealand veterinary journal》2013,61(12):245-248
A serological survey of 213 randomly chosen dairy farm residents in the Manawatu showed that 66 (34%) of the people who milked cows had leptospiral titres ≤ 1:24 by the Microscopic Agglutination Test. Forty-eight (72.7%) of these people had titres to hardjo, while 29 (43.9%) had titres to pomona. Dual hardjo/pomona titres occurred in 12 people. Ballum and Copenhageni accounted for 8% of the titres found. Women milkers and farm residents who did not milk were all serologically negative. A third of the seropositive milkers had a history of clinical leptospirosis. Other factors which significantly correlated with leptospiral titres included the time spent in the dairy shed during milking, the wearing of shorts, the keeping of pigs for sale, and the number of years the individual had been working on a dairy farm. The type of milking shed and the size of the herd were interrelated and both showed strong trends towards a correlation with serological prevalence. 相似文献
1000.
Summary A Leptospira interrogans serogroup australis serovar lora infection in a stud farm is reported. During three successive years (1984–1986) clinical leptospirosis with a severe often rapid, fatal course was seen in 12 foals. Clinical examination revealed severe respiratory distress, depression and pyrexia. Other symptoms were diarrhea (2), jaundice (1), and an unsteady gait (1). Morphological characteristics of the disease were massive pulmonary haemorrhage and haemorrhagicthrombotic or extracapillary glomerulonephritis with tubulonephrosis and interstitial oedema. In most foals high or increasing MAT titres to serovar bratislava were found; from one foal Leptospira interrogans serovar lora was isolated. Serological examination of all 56 mares at the farm (August 1986) revealed antibodies to serovar bratislava in 64 per cent of the animals. These findings support the idea that Leptospira interrogans serovar bratislava and closely related strains (in this study serovar lora) may be adapted to and maintained by the horse population. 相似文献