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71.
Queiros J Alvarez J Carta T Mateos A Ortiz JA Fernández-de-Mera IG Martín-Hernando MP Gortázar C 《Preventive veterinary medicine》2012,104(3-4):327-334
Tuberculosis (TB) in deer is a serious zoonotic disease of worldwide distribution. Detection of infected animals is usually performed using single or comparative skin-testing (SST/CST), although false responses due to sensitization to other mycobacteria may occur, hampering diagnostic specificity. We describe the evolution of the responses to the SST, CST and to an in-house serological assay in a red deer farm subjected to regular TB testing in southern Spain in an attempt to understand the dynamics of possible non-specific reactions occurring under field conditions. We performed 2288 skin-tests and ELISAs in nine sampling periods between May 2009 and January 2011. In May 2010, a strong increase in skin fold thickness in response to avian purified protein derivative (PPD) (mean=4.0mm, 95% CI=3.5-4.5) and bovine PPD (mean=1.8mm, 95% CI=1.6-2.0) was observed in yearling deer hinds (n=150), compared to values recorded for the same individuals in November 2009 (avian PPD: mean=0.7 mm, 95% CI=0.6-0.8 and bovine PPD: mean=0.7 mm, 95% CI=0.6-0.7) and in January 2011 (avian PPD: mean=2.2mm, 95% CI=1.9-2.4 and bovine PPD: mean=1.1mm, 95% CI=1.0-1.2). Using SST, 54 animals (36%) of the yearlings tested in May 2010 would have been classified as positive reactors, while none of them was positive in the CST. The five animals with highest skin fold increases to mycobacterial antigens were culled and subjected to post-mortem analysis, which confirmed the absence of Mycobacterium tuberculosis complex (MTBC) infection but demonstrated the presence of environmental mycobacteria and closely related bacteria in four out of the five analyzed animals. Our results demonstrated how non-specific responses to mycobacterial antigens can adversely affect the specificity of TB diagnosis based on the SST. Thus, once TB infection has been ruled out using confirmatory techniques, application of comparative diagnostic tests is highly advisable to maximize test specificity and avoid the slaughter of false positive reactors. 相似文献
72.
Shakeel Ahmad Ashfaq Ahmad Cecilia Manuela Tojo Soler Hakoomat Ali Muhammad Zia-Ul-Haq Jakarat Anothai Abid Hussain Gerrit Hoogenboom Mirza Hasanuzzaman 《Precision Agriculture》2012,13(2):200-218
The objectives of this study were to evaluate the performance of the cropping system model (CSM)-CERES-Rice to simulate growth
and development of an aromatic rice variety under irrigated conditions in a semiarid environment of Pakistan and to determine
the impact of various plant densities and nitrogen (N) application rates on grain yield and economic return. The crop simulation
model was evaluated with experimental data collected in experiments that were conducted in 2000 and 2001 in Faisalabad, Punjab,
Pakistan. The experimental design was a randomized complete block design with three replications and included three plant
densities (one seedling hill−1, PD1; two seedlings hill−1, PD2; and three seedlings hill−1, PD3) and five N fertilizer regimes (control, N0; 50 kg ha−1, N50; 100 kg ha−1, N100; 150 kg ha−1, N150; and 200 kg ha−1, N200). To determine the most appropriate combination of plant density and N levels, four plant densities from one seedling hill−1 to four seedlings hill−1 and 13 N levels ranging from 0 to 300 kg N ha−1 (52 scenarios) were simulated for 35 years of historical daily weather data under irrigated conditions. The evaluation of
CSM-CERES-Rice showed that the model was able to simulate growth and yield of irrigated rice in the semiarid conditions, with
an average error of 11% between simulated and observed grain yield. The results of the stimulation analysis result showed
that two seedlings hill−1 along with 200 kg N ha−1 (PD2N200) produced the highest yield as compared to all other scenarios. Furthermore, the economic analysis through the mean gini
dominance also showed the dominance of this treatment (PD2N200) compared to the other treatment combinations. Thus, the management scenario that consisted of two seedlings hill−1 and 200 kg N ha−1 was the best for high yield and monitory return of irrigated rice in the semiarid environment. The mean monetary returns
ranged from 291 US $ ha−1 to 1 460 US $ ha−1 to 1 460 US ha−1 among the 52 production options that were simulated. This approaching was demonstrated as effective way to optimize the density
and N management for high yield and monetary return. It will help the rice production. 相似文献
73.
Ana Paola Balderrama-Carmona Pablo Gortáres-Moroyoqui Luis H. Álvarez Ruth Gabriela Ulloa-Mercado Luis Alonso Leyva-Soto Lourdes Mariana Díaz-Tenorio 《Water, air, and soil pollution》2017,228(5):185
A quantitative microbial risk assessment method can be used to evaluate infections probabilities for microorganisms in a specific place. The methodology provides suitable information to generate strategies focusing on health problems. Giardia cysts (GC) and Cryptosporidium oocysts (CO) are considered emerging pathogens that can infect human and animals by ingesting contaminated food or water, where food and water are transport vehicles for these parasites. Studies for GC and CO have reported occurrences for these parasites in water up to 100%, and some of these studies documented a number of cases, about 403,000 people, infected worldwide. This review is focused on compiling the most relevant works assessing the risk for GC and CO and their presence in different water samples that are susceptible for direct and indirect human consumption. The annual risk infection probability for these parasites has been reported from different water sources, with a range between 1 × 10?6 and 1, while the world standard regulation is 1 × 10?4. The infection probability depends not only on water quality but also on water treatment implementations. 相似文献
74.
Vladimir López María Angeles Risalde Marinela Contreras Lourdes Mateos‐Hernández Joaquin Vicente Christian Gortázar José de la Fuente 《Journal of fish diseases》2018,41(10):1515-1528
Control of mycobacterial infection constitutes a priority for human and animal health worldwide. However, effective vaccines are needed for the control of human and animal tuberculosis (TB). Adult zebrafish have become a useful model for studying the pathophysiology of mycobacterial infection and for the development of novel interventions for TB control and prevention. Recently, parenteral and oral immunization with the heat‐inactivated Mycobacterium bovis vaccine (M. bovis IV) protected wild boar against TB. The objectives of this study were to provide additional support for the role of M. bovis IV in TB control using the zebrafish model and to conduct the first trial with this vaccine for the control of fish mycobacteriosis. The results showed that M. bovis IV protected zebrafish against mycobacteriosis caused by low and high infection doses of Mycobacterium marinum and provided evidence suggesting that the protective mechanism elicited by M. bovis IV in zebrafish as in other species is based on the activation of the innate immune response through the C3 pathway, with a role for the regulatory protein Akr2 in this process. These results encourage the use of M. bovis IV for TB control in different species. 相似文献
75.
Gerrit Gort Wim J. M. Koopman Alfred Stein Fred A. van Eeuwijk 《Journal of Agricultural, Biological & Environmental Statistics》2008,13(2):177-198
AFLP is a frequently used DNA fingerprinting technique that is popular in the plant sciences. A problem encountered in the
interpretation and comparison of individual plant profiles, consisting of band presence-absence patterns, is that multiple
DNA fragments of the same length can be generated that eventually show up as single bands on a gel. The phenomenon of two
or more fragments coinciding in a band within an individual profile is a type of homoplasy, that we call collision. Homoplasy
biases estimates of genetic similarity. In this study, we show how to calculate collision probabilities for bands as a function
of band length, given the fragment count, the band count, or band lengths. We also determine probabilities of higher order
collisions, and estimate the total number of collisions for a profile. Since short fragments occur more often, short bands
are more likely to contain collisions. For a typical plant genome and AFLP procedure, the collision probability for the shortest
band is 25 times larger than for the longest. In a profile with 100 bands a quarter of the bands may contain collisions, concentrated
at the shorter band lengths. All calculations require a careful estimate of the monotonically decreasing fragment length distribution.
Modifications of Dice and Jaccard coefficients are proposed. The principles are illustrated on data from a phylogenetic study
in lettuce. 相似文献
76.
van Dillen SM Hiddink GJ Koelen MA de Graaf C van Woerkum CM 《Public health nutrition》2008,11(5):478-485
OBJECTIVES: To unravel the concept of nutrition awareness, as it relates to risky personal nutrition-related behaviours, and to assess the sociodemographic and psychosocial correlates of nutrition awareness. DESIGN: Data were collected in a cross-sectional study with the aid of a face-to-face interview-assisted questionnaire that was based on the Precaution Adoption Process Model and Stages of Change Model. SETTING: Dutch consumer homes. SUBJECTS: Six hundred and three Dutch adults aged 18 to 80 years, selected from a panel. RESULTS: Our model explains nutrition awareness well (explained variance 53.7%). Psychosocial correlates were involvement with nutrition, health awareness, association with healthy food, perceived relevance of eating less fat, association with necessity, perceived relevance of vitamins, and perceived attributes of independent organisations. Sociodemographic correlates were gender and age. The relationship between nutrition awareness and nutrition-related behaviours proved to be very complicated. CONCLUSIONS: The value of our study is that it unravels the concept of nutrition awareness. Understanding the correlates of nutrition awareness can contribute to a more effective application of behavioural change models. Our results support increasing involvement with nutrition through personalising and tailoring to the motivational stage. 相似文献
77.
78.
79.
GerritKarssen 《云南农业大学学报(自然科学版)》1999,14(Z1):126-126
Roo-t knot nematodes represent a relatively small but economically important group of obligate plant pathogens.They are distributed world-wide and parasitise on almost every higher plant species.More than eighty species have been described during the last fifty years. 相似文献
80.
Water use and water use efficiency of sweet corn under different weather conditions and soil moisture regimes 总被引:1,自引:0,他引:1
Axel Garcia y Garcia Larry C. Guerra Gerrit Hoogenboom 《Agricultural Water Management》2009,96(10):1369-1376
Plant growth and development are influenced by weather conditions that also affect water use (WU) and water use efficiency (WUE) and ultimately, yield. The overall goal of this study was to determine the impact of weather and soil moisture conditions on WU and WUE of sweet corn (Zea mays L. var rugosa). An experiment consisting on three planting dates was conducted in 2006 at The University of Georgia, USA. A sweet corn genotype sh2 was planted on March 27 under irrigated and rainfed conditions and on April 10 and 25 under irrigated conditions only. Soil moisture was monitored using PR2 probes. Rainfall and irrigation were recorded with rain gauges installed in the experimental area while other weather variables were recorded with an automatic weather station located nearby. A water balance was used to obtain the crop's daily evapotranspiration (ETc). WUE was calculated as the ratio of fresh and dry matter ear yield and cumulative ETc. The potential soil moisture deficit (Dp) approach was used to determine the crop's moisture stress. Results were analyzed using a single degree freedom contrast, linear regression, and the least significant difference. WU and WUE of sweet corn were both markedly affected by the intra-seasonal weather variability and Dp. For both variables, significant (p < 0.05) differences were found between planting dates under irrigated conditions and between the irrigated and rainfed treatments. WU was as high as 268 mm for the April 10 planting date under irrigated conditions and as low as 122 mm for the March 27 planting date under rainfed conditions. The maximum soil moisture deficit was reached at the milky kernel stage and was as high as 343 mm for the March 27 planting date under rainfed conditions and as low as 260 mm for the April 10 planting date under irrigated conditions. Further work should focus on the impact of the intra-seasonal weather variability and soil moisture conditions during different crop stages to determine critical periods that affect yield. 相似文献