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排序方式: 共有489条查询结果,搜索用时 15 毫秒
1.
Brownlie J Nuttall PA Stott EJ Taylor G Thomas LH 《Veterinary immunology and immunopathology》1980,1(4):371-378
Certain immunological responses of 4-6 month old calves experimentally inoculated with either cytopathic or non-cytopathic bovine virus diarrhoea virus (BVDV) were compared with those of uninfected control calves. The tests used to demonstrate the immunological responses were the transformation of lymphocytes by PHA mitogen, the percentage of lymphocytes with surface immunoglobulin, and the antibody titres induced by an intravenous inoculation of killed Brucella abortus. There were no significant differences between the two groups of calves and therefore, the mild experimental disease produced by BVDV did not appear to affect adversely the immunological response. 相似文献
2.
Eugenia Fezza Joe M. Roberts Toby J. A. Bruce Lael E. Walsh Michael T. Gaffney Tom W. Pope 《Pest management science》2023,79(11):4635-4643
BACKGROUND
Monitoring is an integral component of integrated pest management (IPM) programmes used to inform crop management decisions. Vine weevil, Otiorhynchus sulcatus F. (Coleoptera: Curculionidae), continues to cause economically significant losses in horticultural crops due to an inability to reliably detect the presence of this species before crop damage occurs. To improve vine weevil monitoring we investigated the behavioural responses of adult vine weevils to visual (monitoring tool shade/colour, height and diameter as well as the effect of monitoring tool and plant density) and olfactory (host plant and conspecifics) cues under glasshouse conditions.RESULTS
Monitoring tool shade, height and diameter all influenced monitoring tool efficacy, with individuals exhibiting a preference for black, tall and wide monitoring tools. The total number of individuals recorded in monitoring tools increased with monitoring tool density. By contrast, plant density did not influence the number of individuals recorded in monitoring tools. Yew-baited monitoring tools retained a larger number of individuals compared to unbaited ones. Similarly, more vine weevils were recorded in monitoring tools baited with yew and conspecifics than in unbaited monitoring tools or those baited with only yew. Baiting monitoring tools with conspecifics alone did not enhance the number of vine weevils recorded in monitoring tools.CONCLUSIONS
Our study confirms that visual and olfactory cues influence vine weevil behaviour. This provides information on key factors that influence vine weevil monitoring tool efficacy and can be used to inform the development of a new monitoring tool for this pest. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献3.
4.
The genetic and antigenic diversity observed in field isolates of bovine viral diarrhoea virus (BVDV) is thought to occur during acute infection because of the genetic stability observed in BVDV throughout the lifetime of persistently infected (PI) cattle. In this study, 15 cows in early pregnancy were inoculated with identical challenge doses obtained from a single infectious inoculum of the virologically cloned isolate Pe515nc. In order to examine the diversity that may develop in utero in the PI foetus, the variable E2 sequence of the virus isolated directly from the serum of each PI calf was compared. A high degree of sequence similarity was demonstrated, with 0-4 nucleotide differences out of 608 bases compared. Thus, the virus showed relatively few genomic changes in any of the PI calves, although we observed that the in utero environment did provide some opportunity for genetic variation to become established. 相似文献
5.
McKenzie EC Valberg SJ Godden SM Pagan JD Carlson GP MacLeay JM DeLaCorte FD 《American journal of veterinary research》2002,63(7):1053-1060
OBJECTIVE: To determine whether plasma, urine, and fecal electrolyte and mineral concentrations differ between clinically normal horses and Thoroughbreds with recurrent exertional rhabdomyolysis (RER) after consumption of diets varying in cation-anion balance. ANIMALS: 5 Thoroughbred mares with RER and 6 clinically normal mixed-breed mares. PROCEDURE: Each of 3 isocaloric diets designated as low, medium, and high on the basis of dietary cation-anion balance (DCAB) values of 85, 190, and 380, respectively, were fed to horses for 14 days. During the last 72 hours, 3 horses with RER and 3 control horses had daily urine and fecal samples obtained by total 24-hour collection. Remaining horses had urine samples collected daily by single catheterization. RESULTS: For each diet, no differences existed between horses with RER and control horses in plasma pH, electrolyte concentrations, and creatine kinase activity or in urine pH and renal fractional excretion (FE) values. Plasma pH, strong ion difference, bicarbonate and total carbon dioxide concentrations, and base excess decreased and plasma chloride and ionized calcium concentrations increased with decreasing DCAB. Urine pH decreased with decreasing DCAB. The FE of chloride and phosphorus were greatest for horses fed the low diet. The FE values for all electrolytes exept magnesium did not differ between urine samples obtained by single catheterization and total 24-hour collection. Daily balance of calcium, phosphorus, sodium, chloride, and potassium did not differ significantly among horses fed the various diets. CONCLUSIONS: In clinically normal horses and in horses with RER, the DCAB strongly affects plasma and urine pH and the FE of sodium, potassium, chloride, and phosphorus. 相似文献
6.
Sunico SK Hamel C Styner M Robertson ID Kornegay JN Bettini C Parks J Wilber K Smallwood JE Thrall DE 《Veterinary radiology & ultrasound》2012,53(3):266-272
Advances in magnetic resonance (MR) imaging and three-dimensional (3D) modeling software provide the tools necessary to create sophisticated, interactive anatomic resources that can assist in the interpretation of MR images of extremities, and learning the structure and function of limb musculature. Modeling provides advantages over dissection or consultation of print atlases because of the associated speed, flexibility, 3D nature, and elimination of superimposed arrows and labels. Our goals were to create a diagnostic atlas of pelvic limb muscles that will facilitate interpretation of MR images of patients with muscle injury and to create a 3D model of the canine pelvic limb musculature to facilitate anatomic learning. To create these resources, we used structural segmentation of MR images, a process that groups image pixels into anatomically meaningful regions. The Diagnostic Atlas is an interactive, multiplanar, web-based MR atlas of the canine pelvic limb musculature that was created by manually segmenting clinically analogous MR sequences. Higher resolution volumetric MR and computed tomography (CT) data were segmented into separately labeled volumes of data and then transformed into a multilayered 3D computer model. The 3D Model serves as a resource for students of gross anatomy, encouraging integrative learning with its highly interactive and selective display capabilities. For clinicians, the 3D Model also serves to bridge the gap between topographic and tomographic anatomy, displaying both formats alongside, or even superimposed over each other. Both projects are hosted on an open-access website, http://3dvetanatomy.ncsu.edu/ 相似文献
7.
Young NJ Thomas CJ Thompson I Collins ME Brownlie J 《Preventive veterinary medicine》2005,72(1-2):115-20; discussion 215-9
Immune responses to non-structural protein 3 (NS3) of bovine viral diarrhoea virus (BVDV) were investigated. cDNA encoding NS3 from type 1a BVDV was used to vaccinate five calves, another five calves remained unvaccinated. Three weeks after final vaccination animals were challenged intranasally with heterologous type 1a BVDV. Anti-NS3 antibodies were detected in only one animal post-vaccination. Partial protection from virus challenge was observed in the vaccinates. Virus was not isolated from nasal mucosa of two vaccinates, and virus clearance from nasal mucosa was faster in the vaccinates compared to the controls. While elevated rectal temperatures were evident in both groups 7 days post-challenge, the mean increase in the controls was twice that observed in the vaccinates. In conclusion, NS3 DNA vaccination induced humoral immunity in one calf, and prevented fever and virus establishment in the nasal mucosa in 2/5 calves, demonstrating the efficacy of NS3 vaccination, which may benefit future development of pestivirus and flavivirus vaccines. 相似文献
8.
Joe M. Fox Addison L. Lawrence Eunice Li‐Chan 《Journal of the World Aquaculture Society》2009,40(2):171-181
Tail muscle tissue free amino acids (FAA) concentration is reported for subadult (4.3 g) Litopenaeus vannamei fed diets containing only protein‐bound amino acids, crystalline lysine as a supplement to protein‐bound lysine, and only crystalline amino acids (CAA). FAA were determined in shrimp at 0.00, 0.25, 0.5, 1, 2, 4, and 8 h postfeeding. Highest total tissue concentrations of essential amino acids and individual amino acids were typically observed 4 h postfeeding for shrimp fed intact and crystalline lysine‐supplemented feeds. Those shrimp offered diets containing only CAA showed no tissue maxima. Similar uptake patterns for lysine shown by shrimp fed the intact and crystalline lysine‐supplemented diet indicate the potential use of small amounts of crystalline lysine in shrimp feeds. 相似文献
9.
微喷灌结合滴灌对温室高温环境和作物生长生理特性的影响 总被引:1,自引:3,他引:1
微喷灌结合滴灌是指在作物根区滴灌的基础上对作物冠层进行微喷灌来改善作物生长环境的一种灌水方式。为了探明微喷灌结合滴灌(micro-sprinkler irrigation combined with drip irrigation,MSDI)和地表滴灌(surface drip irrigation,SDI)2种灌水方式下温室高温环境及作物生长生理特性的差异及响应规律,该研究以黄瓜为试验对象,于2017年2-6月开展了2种灌水方式下温室环境及黄瓜生长生理特性的观测试验。结果表明:在改变温室环境方面,MSDI灌水方式较SDI可增加温室内相对湿度,降低气温,同时降低叶片温度约4℃;在作物生长生理特性方面,采用MSDI可增加黄瓜株高与茎粗,降低作物茎流速率,促进黄瓜生长;2种灌水方式下黄瓜最大光合效率几乎一致,分别为0.74和0.77,但日平均实际光合效率差异明显,分别为0.57和0.47,MSDI灌水方式下黄瓜叶片日平均气孔导度和光合速率比SDI方式分别高182.8%和92.4%。该研究成果对于合理调控温室高温环境、提高温室作物产量具有重要的指导意义。 相似文献
10.
Mak Chanratana Gwang Hyun Han Manoharan Melvin Joe Aritra Roy Choudhury Seshadri Sundaram Md. Abdul Halim 《Archives of Agronomy and Soil Science》2018,64(11):1489-1502
Methylobacterium oryzae CBMB20, a promising plant growth promoting bacteria (PGPB) and a biocontrol agent, was immobilized in different formulations such as wet chitosan, dry chitosan, wet alginate and dry alginate and were tested for tomato plant growth promotion. Chitosan solution (1.5%) with pH 5.5–6.0 and 90 min contact time was found optimal for immobilization. The chitosan formulations showed better entrapment efficiency and good degradability resistance apart from slow release of cells under prolonged incubation. Survivability of bacteria (80%) was observed in wet chitosan formulation even after 90 days of storage at 4°C. The spermosphere survival of bacteria was high in both dry and wet chitosan formulations applied soils even after 21 days under greenhouse conditions. While the alginate formulation degraded fully, partial degradation of chitosan formulation was observed even after 30 days, indicating its ability to support the survival of M. oryzae CBMB20 in soil. Plants inoculated with wet chitosan formulation registered 1.3 fold increase in the shoot and root length and dry weight compared to other treatments. Hence, chitosan formulation supporting better plant growth compared to alginate will be a better carrier for taking bacteria to the plant rhizosphere and thereby promote plant growth. 相似文献