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1.
Abdulridha Jaafar Ampatzidis Yiannis Kakarla Sri Charan Roberts Pamela 《Precision Agriculture》2020,21(5):955-978
Early and accurate diagnosis is a critical first step in mitigating losses caused by plant diseases. An incorrect diagnosis can lead to improper management decisions, such as selection of the wrong chemical application that could potentially result in further reduced crop health and yield. In tomato, initial disease symptoms may be similar even if caused by different pathogens, for example early lesions of target spot (TS) caused by the fungus Corynespora cassicola and bacterial spot (BS) caused by Xanthomonas perforans. In this study, hyperspectral imaging (380–1020 nm) was utilized in laboratory and field (collected by an unmanned aerial vehicle; UAV) settings to detect both diseases. Tomato leaves were classified into four categories: healthy, asymptomatic, early and late disease development stages. Thirty-five spectral vegetation indices (VIs) were calculated to select an optimum set of indices for disease detection and identification. Two classification methods were utilized: (i) multilayer perceptron neural network (MLP), and (ii) stepwise discriminant analysis (STDA). Best wavebands selection was considered in blue (408–420 nm), red (630–650 nm) and red edge (730–750 nm). The most significant VIs that could distinguish between healthy leaves and diseased leaves were the photochemical reflectance index (PRI) for both diseases, the normalized difference vegetation index (NDVI850) for BS in all stages, and the triangular vegetation index (TVI), NDVI850 and chlorophyll index green (Chl green) for TS asymptomatic, TS early and TS late disease stage respectively. The MLP classification method had an accuracy of 99%, for both BS and TS, under field (UAV-based) and laboratory conditions.
相似文献2.
Pathogenic bacteria belonging to the family Anaplasmataceae include species of the genera Ehrlichia and Anaplasma. Ehrlichia chaffeensis, first known as the causative agent of human monocytic ehrlichiosis, also infects several vertebrate hosts including white-tailed deer, dogs, coyotes and goats. E. chaffeensis is transmitted from the bite of an infected hard tick, such as Amblyomma americanum. E. chaffeensis and other tick-transmitted pathogens have adapted to both the tick and vertebrate host cell environments. Although E. chaffeensis persists in both vertebrate and tick hosts for long periods of time, little is known about that process. Immunological studies will be valuable in assessing how the pathogen persists in nature in both vertebrate and invertebrate hosts. Understanding the host immune response to the pathogen originating from dual host backgrounds is also important to develop effective methods of diagnosis, control and treatment. In this paper, we provide our perspective of the current understanding of the immune response against E. chaffeensis in relation to other related Anaplasmataceae pathogens. 相似文献
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A. K. Dang Suman Kapila Maneesh Purohit Charan Singh 《Tropical animal health and production》2009,41(7):1213-1217
Colostrum samples were collected from 8 Murrah buffaloes on days 1, 2, 3, 4 and 5 after calving. Levels of IgG averaged 54.0 mg/ml
at calving, then decreased significantly (P < 0.01). IgA and IgM on day 1 were 3.22 mg/ml and 5.22 mg/ml, respectively; both
decreased during the first five days after calving. Values of IgA and IgM were higher than those reported in cows. SCC values,
which were high at calving (500 000 per ml), reduced significantly (P < 0.01) on day 2, then decreased slightly until day
5 (180 000 per ml). At calving, macrophages were the most prominent cells in buffalo colostrum, followed by lymphocytes and
neutrophils. Phagocytic activity was 23% at calving and reduced significantly (P < 0.01) to 14% on day 5. Phagocytic index
was highest in the first colostrum, and then decreased non-significantly. 相似文献
4.
Ravi Charan Padinhate Purayil Suresh Babu Gundaboena Venugopal Narinder Kumar Chadha Kommula Bhaskara Sreeramamurty 《Aquaculture International》2014,22(2):689-697
In India, many of the fish farmers stock 1-year-old stunted fishes (stunted yearlings) of Indian major carps (IMC) for enhancing fish production through compensatory growth, but many of them observed problems of early maturation in these fishes. Application of aromatase inhibitors for deceleration of ovarian maturation is one of the probable solutions to mitigate this issue. In the present study, a synthetic aromatase inhibitor letrozole [25 (L25) and 50 (L50) mg kg?1 feed] and a plant-derived aromatase inhibitor, grape seed extract [100 (G100) and 200 (G200) mg kg?1 feed], were fed to stunted yearlings of rohu (Labeo rohita) for 45 days well before the onset of breeding season. Maturation indices such as gonadosomatic index (GSI) and serum oestradiol (E) levels indicated a dose-dependent inhibition of ovarian development in the aromatase-inhibitor-treated fish. Higher dose of letrozole (GSI, 15.12 ± 0.18; E, 3.19 ± 0.42) and grape seed extract (GSI, 16.90 ± 0.40; E, 3.60 ± 0.75) were found to be more effective since control fish showed further advancement in maturation (GSI, 21.20 ± 1.10; E, 7.33 ± 0.74) during the peak breeding season (15th June). Histological observations also confirmed the results revealing a delayed initiation of ovarian development in the case of higher doses of letrozole and grape seed extracts. These results indicate the possible use of aromatase inhibitors in arresting the early maturation process in IMC. 相似文献
5.
Two 12-year-old cats were diagnosed with chronic kidney disease (CKD) based on physical examination, clinicopathologic data and, in one case, abdominal ultrasound findings. Approximately 1 year after the initial diagnosis of CKD both cats developed renal transitional cell carcinoma (TCC)--bilateral in one cat. Based on post-mortem examination, one cat had no evidence of metastasis and the other had metastasis to the large intestine, heart and lungs. This is the first report of de novo bilateral renal TCC in a cat, as well as the first report of renal TCC developing in cats with previous history of confirmed CKD. 相似文献
6.
Haileigh K. Avellar John D. Lutter Charan K. Ganta Warren Beard Joseph R. Smith Naveen Jonnalagadda Sarah Peloquin Qing Kang Kanwal Ayub 《Canadian journal of veterinary research》2022,86(1):59
Septic arthritis is considered a medical emergency. Disease following bacterial colonization can lead to significant morbidity and mortality and requires costly treatment. Antimicrobial properties of regenerative therapies, including mesenchymal stromal cells and platelet products, have been researched extensively in human medicine. Although fewer studies have been conducted in veterinary species, they have shown promising results. The purpose of this study was to evaluate bacterial suppression by equine platelet lysate (EPL) and adipose-derived mesenchymal stromal cells (ASCs) in vitro. We hypothesized that both products would significantly inhibit the growth of Staphylococcus aureus and Escherichia coli. Pooled blood from 10 horses was used for production of EPL. Mesenchymal stromal cells were isolated from adipose tissue harvested from the gluteal region of 3 horses. The study evaluated 3 treatment groups: 10 × EPL, 1.6 million ASCs, and a control, using an incomplete unbalanced block design with repeated measurements. Optical density readings and colony-forming units/mL were calculated at 0, 3, 6, 9, 12, 18, and 24 hours. Decreased bacterial growth was seen at multiple time points for the S. aureus-ASC and S. aureus-EPL treatments, supporting our hypothesis. Increased bacterial growth was noticed in the E. coli-EPL group, with no difference in the E. coli-ASC treatment, which opposed our hypothesis. A clear conclusion of antimicrobial effects of EPL and ASCs cannot be made from this in vitro study. Although it appears that ASCs have a significant effect on decreasing the growth of S. aureus, further studies are needed to explore these effects, particularly in Gram-positive bacteria. 相似文献
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A rare case of hermaphroditism accompanied with ectopic sigmoid kidney in cross-bred calf is reported. Findings revealed fused kidneys located near urinary bladder, and presence of uterus, vagina, penis and testicles. Both urinary and genital defects seemed to occur in combination and to be interrelated. 相似文献
9.
To investigate the effect of boosting immunity via mucosal route vis-a-vis parenteral route in the mouse model of haemorrhagic septicaemia, mice preimmunized with OMP of Pasteurella multocida (B:2) were immunized with 102 cfu of P. multocida via intranasal and subcutaneous routes. Mice were challenged through intranasal route (natural route of infection) with 108 cfu 14 days after immunization. Group of mice which were immunized intranasally showed significant protection (P < 0.05) of 88% as compared to 50% protection in group of mice immunized subcutaneously. In the control group of mice, 100%
mortality occurred within 48 h. of challenge. The results of present study indicated that boosting of immunity via mucosal route in mice preimmunized with OMP provided better protection against P. multocida. This study may have implications for developing better vaccination strategies for the natural host. 相似文献
10.
Haemorrhagic septicaemia (HS) is an endemic disease of bovines, occuring in most tropical regions of Asia and Africa. In the present study, the suitability of using mice to study pathogenesis of HS was assessed using mortality, mean death time and bacterial multiplication in vital organs after infection with live P multocida. Mice were infected with 105, 103 and 101?cfu of P. multocida B:2 via intranasal and subcutaneous routes along with control groups. Bacterial multiplication in lung, liver and spleen of mice were determined at 24 h interval after intranasal and subcutaneous challenge. More than 80 % of challenged mice died within 48 h of inoculation, irrespective of the dose and route of inoculation. A heavy bacterial load (up to 108?cfu) was observed in lung, liver and spleen of mice titrated at 24 h and following death of mice. Results of the present study indicate that even ten bacteria are enough to cause mortality in mice and the organism multiplies rapidly in respiratory epithelium and disseminated to other vital organs viz liver and spleen suggesting the important role of mouse model in investigating the pathogenesis and challenge studies during vaccine development. 相似文献