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ABSTRACT A novel whitefly-transmitted member of the family Potyviridae was isolated from a squash plant (Cucurbita pepo) with vein yellowing symptoms in Florida. The virus, for which the name Squash vein yellowing virus (SqVYV) is proposed, has flexuous rod-shaped particles of approximately 840 nm in length. The experimental host range was limited to species in the family Cucurbitaceae, with the most dramatic symptoms observed in squash and watermelon, but excluded all tested species in the families Amaranthaceae, Apocynaceae, Asteraceae, Chenopodiaceae, Fabaceae, Malvaceae, and Solanaceae. The virus was transmitted by whiteflies (Bemisia tabaci) but was not transmitted by aphids (Myzus persicae). Infection by SqVYV induced inclusion bodies visible by electron and light microscopy that were characteristic of members of the family Potyviridae. Comparison of the SqVYV coat protein gene and protein sequences with those of recognized members of the family Potyviridae indicate that it is a novel member of the genus Ipomovirus. A limited survey revealed that SqVYV also was present in watermelon plants suffering from a vine decline and fruit rot recently observed in Florida and was sufficient to induce these symptoms in greenhouse-grown watermelon, suggesting that SqVYV is the likely cause of this disease. 相似文献
23.
Jinelle A. Webb Monica Rosati Dinaz Z. Naigamwalla Alice Defarges 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(1):1213-1218
Voiding urohydropropulsion and cystoscopy are routine procedures performed in the dog for diagnostic and therapeutic purposes. These procedures are typically performed under general anesthesia. The purpose of this study was to describe the use of medetomidine-based sedation protocols to perform voiding urohydropropulsion and cystoscopy in cardiovascularly healthy, non-diabetic dogs without evidence of urinary obstruction, renal disease, or hepatic disease. Results of this study revealed significantly shorter procedure times and decreased cost in sedated dogs, with diagnostic and therapeutic outcomes equivalent to those of patients that underwent general anesthesia. Based on the results of this retrospective study, the authors recommend medetomidine-based sedation protocols for voiding urohydropropulsion and cystoscopy in appropriately selected patients. 相似文献
24.
KC Silva‐Santos CR Ferreira GMG Santos MN Eberlin LS Siloto CO Rosa TN Marcantonio MM Seneda 《Reproduction in domestic animals》2014,49(5):711-718
The aim of the present study was to compare the lipid profile in oocytes of indicus and 1/2 indicus × taurus cows with high and low antral follicle count (AFC)/oocyte yields. After an OPU procedure (D0), antral follicles ≥3 mm were counted by ultrasonography (D4, 19, 34, 49, 64), and cows were assigned to groups with either high AFC (≥30 follicles; indicus, NH group; 1/2 indicus × taurus, AH group) or low AFC (≤15 antral follicles; indicus, NL group; 1/2 indicus × taurus, AL group). The lipid profiles of the oocytes were determined by MALDI‐MS. For GI, GII and GIII oocytes, the indicus samples tend to cluster separately from the 1/2 indicus × taurus samples. The lipid species [PC (P‐38:5) + H]+ and/or [PC (P‐36:2) + Na]+, [PC (38:2) + H]+, [PC (38:5) + Na]+ and [TAG (60:8) + NH4]+ were more abundant in indicus (NH and NL groups) than 1/2 indicus × taurus. The higher lipid content in the indicus oocytes likely reflects differences in the rate of lipid metabolism and may contribute to oocyte competence and embryo development. 相似文献
25.
The in vitro effects of several steroids on the maturation of intact white sturgeon (Acipenser transmontanus) ovarian follicles were investigated. At the highest concentration (1024 ng ml–1 for the C21 steroids and 1139 ng ml–1 for the C19 steroids), all of the C21 steroids tested, progesterone (P4), 17-hydroxyprogesterone (17OHP), 17,20-dihydroxy-4-pregnen-3-one (17,20-P), 17,(20,21-trihydroxy-4-pregnen-3-one 20-S), 11-deoxycortisol (S) and cortisol (F), as well as testosterone (T) induced germinal vesicle breakdown (GVBD) at 14 and 22 h. At 6 h, only P4 and 17,20-P induced maturation at the highest concentration (1024 ng ml–1). At 14 and 22 h, 11-deoxycortisol was the most potent steroid inducer of GVBD followed by P4, 17OHP, 17,20-P, and 20-S. The steroid 11-hydroxytestosterone (11OHT) was completely ineffective at all concentrations and exposure times. The C21 steroids induced oocyte maturation at concentrations ranging from 4 to 1024 ng ml–1, whereas T induced GVBD at 225 to 1139 ng ml–1. Calculation of the mean effective concentration that induced 50% GVBD (EC50) from the 22 h incubations revealed the following order of potencies: S > P4 > 17OHP > 17,20-P > 20-S >> F > T. These bioassay results, together with previous findings on the endogenous production of steroids by ovarian follicles from gonadotropin-primed females, indicate that more than one steroid has a biological role in the resumption of meiosis in sturgeon oocytes and provides empirical evidence for P4, 17OHP, S, 20-S, and 17,20-P as maturation-inducing steroids in white sturgeon. 相似文献
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27.
The distribution of seabirds west of Scotland was studied relative to water masses in August 1988. Surface salinity was used to indicate the ship's position relative to the water masses described in the literature. Comparisons were made between seabird densities in Inshore Water, the Northern Coastal Current, the Southern Coastal Current and Atlantic/Hebridean Water. Seabird density varied with water mass; some species distributions suggested strong habitat associations. Water masses represent marine habitats, with different physical regimes supporting different marine life; patterns in bird distribution are likely to reflect prey distribution and availability. Manx shearwaters Puffinus puffinus, razorbills Alca torda, guillemots Uria aalge, and kittiwakes Rissa tridactyla were found mostly in Inshore Water, with lower densities in the Northern and Southern Coastal Current water. Only trace numbers of these species occurred in Atlantic/Hebridean Water. Storm petrels Hydrobates pelagicus, fulmars Fulmarus glacialis and puffins Fratercula arctica were found in very low densities in Inshore Water, and were dispersed in higher densities throughout the more oceanic areas. These data suggest that in late summer the Inshore Water of southwestern Scotland has the highest densities of seabirds potentially vulnerable in the event of an oil incident. 相似文献
28.
Mechanical comparison of materials used for extra-capsular stabilisation of the stifle joint in dogs
Objective The mechanical properties of three materials (No. 2 polypropylene, No. 5 polybutilate-coated multifilament polyester and 18, 27 and 36 kg test monofilament nylon leader material) commonly used for extra-capsular stabilisation of the stifle in dogs with cranial cruciate ligament insufficiency were determined. The ability of No. 5 polybutilate-coated multifilament polyester and 36 kg test monofilament nylon leader material, when placed as extra-capsular sutures, to mitigate cranial drawer was evaluated in hindlimbs of cadavers. Design An in vitro mechanical study. Animals Seven pairs of hindlimbs harvested from adult greyhound dogs recently euthanased for other reasons. Procedure Samples of each material, including samples of 27 kg test leader material that had been sterilised by one of three methods (ethylene oxide, one or five cycles in an autoclave), were loaded to determine tensile and stress relaxation properties. The effect of cyclic loading on a No. 5 polybutilate-coated multifilament polyester and 36 kg test leader material was also determined. Using the harvested hindlimbs, cranial drawer was measured before and after transection of the cranial cruciate ligament and on the first and twelfth cycle following extra-capsular stabilisation with either No. 5 polybu-tilate-coated multifilament suture or 36 kg test leader material. Results Leader material was found to have the most suitable mechanical characteristics for use as extracapsular stabilisation of the cranial cruciate ligament deficient stifle. Of the sterilisation methods, ethylene oxide was found to have the least detrimental effects on the handling and material characteristics of the leader material. Stifles stabilised with 36 kg test leader material had significantly less drawer than those stabilised with No. 5 polybutilate-coated multifilament polyester suture. Clinical implications Monofilament nylon leader material would appear to have suitable mechanical properties for extra-capsular stabilisation of the cranial cruciate ligament deficient stifle. If possible the material should be sterilised using ethylene oxide. 相似文献
29.
Twenty-eight growing wether lambs (33.9 kg), adapted to urea for 40 d, were used in a metabolism study to determine if urea impregnation of corn could improve urea utilization. The following diets were compared: 1) whole shelled corn alone, 2) whole shelled corn impregnated with urea, calcium (Ca) as CaCl2, potassium (K) as KC2H3O2, and sulfur (S) as Na2S2O3 X 5H2O, 3) whole shelled corn fed with a dry supplement containing urea, Ca, K and S and 4) whole shelled corn fed with a dry supplement containing soybean meal, Ca and K. Additions were made to provide diets containing 12% crude protein, .37% Ca and .50% K. A 10:1 N (from urea) to S ratio, dry basis was used in urea-containing diets. Corn (90% dry matter) in diet 2 was impregnated by spraying 1.1 liters of an aqueous solution containing the above salts per 10 kg of corn dry matter. After mixing for 10 min in a horizontal mixer, the corn was dried in a laboratory grain drying bin with ambient laboratory air for 48 h. Lambs were fed 350 g of the respective diets plus 35 g orchardgrass hay twice daily during a 20-d metabolism trial. On the last day of the trial, ruminal fluid samples were collected at 0, 1, 2, 3, 4, 5 and 6 h postfeeding and jugular blood was obtained at 0 and 6 h postfeeding. Nitrogen-supplemented diets resulted in increased (P less than .01) absorption and retention of N. Digestibility of dry matter, organic matter and NFE tended to be greater in lambs fed impregnated corn than in lambs fed the other diets.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
30.
Furazolidone induces a cardiotoxicosis when fed in toxic concentrations to newly hatched ducklings. This preliminary experiment was designed to determine if creatine kinase (CK) isoenzymic activities or other serum analytes would be useful as indicators of these cardiac alterations. Sera from 12 ducklings (six fed a control ration and six fed the control ration with 700 mg furazolidone added per kg of feed [700 ppm] for 28 days) were analyzed for CK isoenzymic activities, electrolytes, nitrogenous metabolites, hepatic enzymic activities, bilirubin, and glucose. Statistically significant differences between control and treated groups were detected for creatine kinase MB (CK-MB, cardiac muscle origin) isoenzymic activity and bilirubin, potassium, calcium, and total carbon dioxide concentrations. Differences other than CK-MB isoenzymic activity were generally explained by factors related to the toxicosis or sample handling. These findings suggest that CK-MB isoenzymic activity may be useful to detect and monitor the progress of cardiac injury in furazolidone toxicosis, thereby increasing the usefulness of this model of dilated cardiomyopathy. Our findings, analyzed on the Kodak Ektachem 700 Dry Chemistry Analyzer, are compared with serum chemistry values reported in the literature. 相似文献