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91.
1. A polymerase-chain-reaction (PCR)-based test was adapted to sex the lesser rhea. Feathers instead of blood were used as the source of DNA. 2. The primers used allowed the assignment of sex by amplification of Z and W chromosome linked sequences. 3. This method proved to be safe, accurate and non-invasive. 4. The W chromosome linked fragment was sequenced and compared to other ratite sequences. 相似文献
92.
Ferroglio E Pregel P Accossato A Taricco I Bollo E Rossi L Trisciuoglio A 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2006,53(1):30-33
Intradermal tests were carried out on 18 horses with clinical signs of Culicoides hypersensitivity (CHS) and 23 horses without clinical signs of CHS, and sera from these horses were analysed by SDS-PAGE and Western blotting (W-B). Intradermal injections of 0.1 ml of 25 microg/microl sterile Culicoides extract, 0.1 ml of 1:10,000 histamine (positive control) and 0.1 ml of physiological saline (negative control) were made in the dermis of the middle region of the neck. Analysis of reactions indicated that a 1 cm wheal and a skinfold thickness >10% at 24 h represented a valid cut-off between horses with and without CHS. In these conditions the test, even in winter when clinical signs were absent, had 100% sensitivity and specificity. The W-B was performed after running Culicoides extract on a 12% polyacrylamide gel. The test revealed the presence of several bands with molecular weight ranging from 6 to 200 kDa. In particular, a band of 65 kDa was predominantly found in hypersensitive horses by using an anti-IgE antibody while in normal horses the same band was mainly detected by using an anti-IgG antibody. Our results demonstrated that the skin test is a valid diagnostic test, with high sensitivity and specificity and that the band of about 65 kDa probably corresponds to the allergen involved in the pathogenesis of CHS. 相似文献
93.
Mora JR Iwata M Eksteen B Song SY Junt T Senman B Otipoby KL Yokota A Takeuchi H Ricciardi-Castagnoli P Rajewsky K Adams DH von Andrian UH 《Science (New York, N.Y.)》2006,314(5802):1157-1160
Normal intestinal mucosa contains abundant immunoglobulin A (IgA)-secreting cells, which are generated from B cells in gut-associated lymphoid tissues (GALT). We show that dendritic cells (DC) from GALT induce T cell-independent expression of IgA and gut-homing receptors on B cells. GALT-DC-derived retinoic acid (RA) alone conferred gut tropism but could not promote IgA secretion. However, RA potently synergized with GALT-DC-derived interleukin-6 (IL-6) or IL-5 to induce IgA secretion. Consequently, mice deficient in the RA precursor vitamin A lacked IgA-secreting cells in the small intestine. Thus, GALT-DC shape mucosal immunity by modulating B cell migration and effector activity through synergistically acting mediators. 相似文献
94.
Although primary infection of grapevines by Plasmopara viticola requires splash dispersal of inoculum from soil to leaves, little is known about the role of rain in primary inoculum dispersal. Distribution of rain splashes from soil to grapevine canopy was evaluated over 20 rain periods (0.2 to 64.2 mm of rain) with splash samplers placed within the canopy. Samplers at 40, 80, and 140 cm above the soil caught 4.4, 0.03, and 0.003 drops/cm(2) of sampler area, respectively. Drops caught at 40 and 80 cm (1.5 cm in diameter) were larger than drops at 140 cm (1.3 cm). Leaf coverage by splashed drops, total drop number, and drop size increased with an increase in the maximum intensity of rain (mm/h) during any rain period. Any rainfall led to infection in potted grapevines placed outside on leaf litter containing oospores, if the litter contained germinated oospores at the time of rain; infection severity was unrelated to rain amount or intensity. Results from vineyards also indicate that any rain can carry P. viticola inoculum from soil to leaves and should be considered a splash event in disease prediction systems. Sampling for early disease detection should focus on the lower canopy, where the probability of splash impact is greatest. 相似文献
95.
Perla Chávez Christian Yarlequé Hildo Loayza Víctor Mares Paola Hancco Sylvie Priou María del Pilar Márquez Adolfo Posadas Percy Zorogastúa Jaume Flexas Roberto Quiroz 《Precision Agriculture》2012,13(2):236-255
Potato bacterial wilt, caused by the bacterium Ralstonia solanacearum race 3 biovar 2 (R3bv2), affects potato production in several regions in the world. The disease becomes visually detectable when extensive damage to the crop has already occurred. Two greenhouse experiments were conducted to test the capability of a remote sensing diagnostic method supported by multispectral and multifractal analyses of the light reflectance signal, to detect physiological and morphological changes in plants caused by the infection. The analysis was carried out using the Wavelet Transform Modulus Maxima (WTMM) combined with the Multifractal (MF) analysis to assess the variability of high-resolution temporal and spatial signals and the conservative properties of the processes across temporal and spatial scales. The multispectral signal, enhanced by multifractal analysis, detected both symptomatic and latently infected plants, matching the results of ELISA laboratory assessment in 100 and 82%, respectively. Although the multispectral method provided no earlier detection than the visual assessment on symptomatic plants, the former was able to detect asymptomatic latent infection, showing a great potential as a monitoring tool for the control of bacterial wilt in potato crops. Applied to precision agriculture, this capability of the remote sensing diagnostic methodology would provide a more efficient control of the disease through an early and full spatial assessment of the health status of the crop and the prevention of spreading the disease. 相似文献
96.
Radiative absorption enhancements due to the mixing state of atmospheric black carbon 总被引:3,自引:0,他引:3
CD Cappa TB Onasch P Massoli DR Worsnop TS Bates ES Cross P Davidovits J Hakala KL Hayden BT Jobson KR Kolesar DA Lack BM Lerner SM Li D Mellon I Nuaaman JS Olfert T Petäjä PK Quinn C Song R Subramanian EJ Williams RA Zaveri 《Science (New York, N.Y.)》2012,337(6098):1078-1081
Atmospheric black carbon (BC) warms Earth's climate, and its reduction has been targeted for near-term climate change mitigation. Models that include forcing by BC assume internal mixing with non-BC aerosol components that enhance BC absorption, often by a factor of ~2; such model estimates have yet to be clearly validated through atmospheric observations. Here, direct in situ measurements of BC absorption enhancements (E(abs)) and mixing state are reported for two California regions. The observed E(abs) is small-6% on average at 532 nm-and increases weakly with photochemical aging. The E(abs) is less than predicted from observationally constrained theoretical calculations, suggesting that many climate models may overestimate warming by BC. These ambient observations stand in contrast to laboratory measurements that show substantial E(abs) for BC are possible. 相似文献
97.
P Scocco E Lepri F Mercati G Vitellozzi L Mechelli P Ceccarelli 《American journal of veterinary research》2012,73(8):1128-1136
Objective-To determine glycohistochemical characteristics of enzootic nasal tumors (ENTs) of sheep, compare results for ENT with those of histologically normal nasal mucosa of sheep, and identify the histologic origin of ENT. Sample-ENT and nasal mucosa samples obtained from cadavers of 5 adult Lacaune sheep with ENT and 5 Lacaune sheep unaffected by ENT, respectively. Procedures-Samples of ENT and nasal mucosa were collected from cadavers of sheep and sectioned. Conventional and lectin histochemical analyses were used to identify glycoconjugates in tissue sections on the basis of their principal chemical groups and principal terminal or internal oligosaccharidic glucidic residues, respectively. Results-ENTs had papillary and tubular portions. Cells in the papillary portion of ENTs had secretion and surface glycoconjugates, which included sulfated glycosaminoglycans and neutral and sialilated glycoproteins. Cells in the tubular portion of ENTs had surface glycoconjugates, which included neutral and sialilated glycoproteins. Both portions of ENTs had C(4)-acetylated sialoderivatives that were not detected in sections of histologically normal nasal mucosa. Conclusions and Clinical Relevance-The papillary portion of ENTs in sheep may originate from respiratory glands and goblet cells. The tubular portion of ENTs in sheep may originate from olfactory glands. Presence of C(4)-acetylated sialoderivatives in cells of ENTs could confer resistance against pathogens to those cells. 相似文献
98.
99.
Collodel G Castellini C del Vecchio MT Cardinali R Geminiani M Rossi B Spreafico A Moretti E 《Reproduction in domestic animals》2012,47(3):372-378
In a previous study, we reported the short- and long-term effects of bacterial lipopolysaccharide (LPS)-induced inflammation on rabbit sperm quality. This study was aimed at exploring the spermatogenesis of the rabbit model focussing on the possible damages occurring to the testis and ejaculated sperm. Twenty New Zealand White rabbit bucks were divided into two groups. One group was inoculated intra-peritoneally with LPS, the other group, considered as control, was treated under the same conditions with saline only. Semen samples were collected before LPS injection, the 7th, 14th, 21st, 30th, 45th, 60th and 90th day after LPS treatment. Semen parameters were evaluated following international guidelines. The kinetic characteristics of ejaculated sperm were analysed using a computer-assisted sperm analyzer and the ultrastructural characteristics were explored by transmission electron microscopy (TEM). On the 7th, 14th and 30th day, testis from treated rabbits and controls were obtained. Testis samples were analysed by light microscopy and TEM. The induced LPS lesions in the testis became evident the 7th day after treatment, with a decrease in germinal cells and with an increase in structurally altered Sertoli cells; normal spermatogenesis was restored on the 30th day. The testicular damages observed on day 7 were probably responsible for the reduction in sperm concentration and motility and the ultrastructural alterations that were detected in the ejaculated sperm on the 14th through the 30th days after treatment. In conclusion, rabbit buck treated with LPS could be a useful model for studying the effect of an induced systemic inflammation on spermatogenesis. 相似文献
100.
Domenico Robbe Augusto Carluccio Alessia Gloria Alberto Contri Mario Ventura Claudia Rita Catacchio Paola Straticò Lucio Petrizzi 《Journal of Equine Veterinary Science》2012
A 4-day-old male Martina Franca donkey foal was evaluated for a forelimb alteration. Clinical examination and radiographs revealed the agenesia of the distal digit. Biochemical parameters were normal, and ultrasonographic evaluation did not identify any relievable organ alteration. Karyotype study revealed an abnormality on chromosome 1. The foal was discharged with a distal limb bandage in which a palmar splint was applied. A poor prognosis for the functionality of the limb was given. In endangered species, such as the Martina Franca donkey, the excessive inbreeding could result in an increase in genetic disorders. These findings shed new light on the possible pathogenesis of the digital dysgenesia. The study of the karyotype could be a useful approach to detect genetic alterations that could or could not be expressed in the animal, especially in endangered species in which a risk of an excessive inbreeding is considerable. These defects should be considered in the choice and selection of the breeders. 相似文献