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71.
Reasons for performing study: Assessment of arytenoid movement has traditionally been performed using upper airway (UA) endoscopy. However, recent work suggests that laryngeal ultrasonography may provide additional complementary information. Objective: To determine the value of laryngeal ultrasonography for the diagnosis of recurrent laryngeal neuropathy in the horse. Hypotheses: Horses with abnormal arytenoid movement (AM) during treadmill UA endoscopy would have increased echogenicity of the left cricoarytenoideus lateralis muscle (CALM) and smaller left CALM and vocalis size while horses with normal AM during treadmill UA endoscopy would have normal echogenicity of the left CALM and similar left and right CALM and vocalis muscle size. Laryngeal ultrasonography would be more accurate than resting endoscopy at predicting abnormal AM. Methods: Medical records were examined to identify Thoroughbred racehorses aged ≥2 years that had undergone resting and treadmill UA endoscopy and laryngeal ultrasonography. Resting and treadmill AM was graded using accepted scales. The treadmill examination was used as the criterion standard for AM. Laryngeal ultrasonography was performed and the relative echogenicity of the left and right CALM and the cross‐sectional area (CSA) of the CALM and vocalis muscle determined. Data analysis included Chi‐squared tests, paired t tests and one‐way ANOVA. Results: The presence of abnormal AM was associated with relative hyperechogenicity of the CALM while normal AM was not. Laryngeal ultrasonography had a sensitivity of 90% and specificity of 98% and resting UA endoscopy had a sensitivity of 80% and specificity of 81% for diagnosis of abnormal AM. CSA of the left CALM and vocalis muscle was not different between groups. Conclusions: Laryngeal ultrasonography has high accuracy for diagnosing abnormal AM. Potential relevance: Ultrasonography is a valuable addition to the diagnostic evaluation of the equine UA. 相似文献
72.
73.
Black walnut (Juglans nigra L.) produces both valuable lumber and a nut crop. Because of this, it is an important tree for agroforestry plantings in
the Midwest USA. However, during processing of the nut crop, the outer tissue of the nut (husks) accumulates in great quantities.
Applying this material to pastures is a possible method of disposal. However, black walnut has been implicated in allelopathic
interactions with numerous plant species and may inhibit the growth of pasture species. Greenhouse and field studies and a
chemical analysis of the husks were conducted to determine the effects of applying walnut husks to orchardgrass (Dactylis glomerata L.) or red clover (Trifolium pratense L.) pastures. Applying husks at rates up to 68 Mg ha−1 to pot-grown orchardgrass resulted in root and shoot yields that were greater than in pots receiving no husks. Field studies
indicated that orchardgrass and red clover benefited from the application of husks. For orchardgrass, significant increases
in growth occurred when husks were applied at a rate of 34 Mg ha−1 while red clover responded to rates up to 68 Mg ha−1. A chemical analysis of husks indicated that significant quantities of N and K were present in walnut husks. A whole effluent
toxicity test (WETT) indicates that runoff from walnut husk-treated pastures, at the rates used in this study, would not adversely
affect aquatic organisms. 相似文献
74.
JL McKIMM-BRESCHKIN JT FARAGHER J WITHELL WM FORSYTH † 《Australian veterinary journal》1990,67(6):205-209
Very virulent Marek's disease viruses (vvMDV), defined as isolates against which the herpesvirus of turkey (HVT) vaccine provide poor protection, have been isolated from poultry flocks in both the United States and Europe. Twenty-one samples from vaccinated Australian flocks, experiencing problems with excessive Marek's disease (MD), were tested for the presence of transmissible MD viruses (MDV). Of the 16 samples which contained a transmissible agent, 14 were pathogenic in chickens, based on the development of MD lesions or depression of the bursa/body weight ratio. Of the pathogenic isolates which have been successfully typed 10 were serotype 1, and one was serotype 2 MDV. Pathogenicity of isolates varied. Several isolates caused tumours in 20-30% of both vaccinated and unvaccinated chickens. Two isolates, MPF6 and MPF23, caused tumours in more than 50% of chickens. When MPF6 and MPF23 were tested in vaccine trials bivalent vaccine gave no better protection against development of MD lesions than a monovalent vaccine. Isolate MPF23 was so pathogenic that lesions were produced in all chickens, regardless of the vaccine protocol used. Therefore vvMDV have been isolated in Australia, and unlike the vaccines tested overseas, bivalent Australian vaccines do not appear to provide greater protection against these vvMDV. 相似文献
75.
Jeryl C. Jones DVM PHD Judith A. Hudson DVM PhD Donald C. Sorjonen DVM MS Charles E. Hoffman CVT BS LATG Kyle G. Braund BVS MVS PhD James C. Wright DVM MS PhD Phillip D. Garrett DVM MS Jan E. Bartels DVM MS 《Veterinary radiology & ultrasound》1996,37(2):133-140
Intraoperative Doppler ultrasonography was used to measure the effects of four experimental nerve root compression treatments (central compression, central-plus-lateral compression, lateral compression, and compression release) on arterial blood flow velocities in the seventh lumbar spinal ganglion of three dogs. Graphed blood flow velocity changes (change = treatment value − pretreatment value) were below baseline during the first three compression treatments and above baseline following compression release. Mean blood flow velocity changes for both central-plus-lateral compression and lateral compression differed (p ≤ 0.05) from changes for central compression. Changes for central-plus-lateral compression did not differ (p > 0.05) from changes for lateral compression. Changes among the first three compression treatments differed (p ≤ 0.05) from changes for compression release. No histologic abnormalities were identified in compressed nerve tissues, compared to contralateral controls. These findings indicate that stenosis within the L7-S1 intervertebral foramen may cause ischemia of the L7 spinal ganglion in dogs. 相似文献
76.
Enzyme-linked immunosorbent assay for detection of antibody to avian encephalomyelitis virus in chickens 总被引:1,自引:0,他引:1
An enzyme-linked immunosorbent assay (ELISA) for the detection of antibody to avian encephalomyelitis virus (AEV) has been developed for determining whether existing AEV control programs adequately protect breeder hens. A partially purified AEV antigen was bound to microcuvettes for reaction with specific primary antibody. A second antibody, rabbit anti-chicken immunoglobulin G (IgG) conjugated with horseradish peroxidase, was employed to react with bound primary IgG. The relative amount of bound primary IgG was detected using ortho-phenylenediamine as a substrate for enzymatic production of a chromogen by horseradish peroxidase. Intensity of absorbance of the chromogen at 490 nm was related to the bound primary antibody by the titration method. Negative antisera were surveyed to establish an appropriate positive/negative cutoff level at twice the mean absorbance of negative sera at a 1:100 dilution. The test reagents for the ELISA were optimized by reagent titrations utilizing known positive and negative antisera for discrimination. The optimized ELISA had a coefficient of variation of from 1.2 to 3.3 for within-assay titer and of 2.4 for between-assay mean titer. Even though the ELISA detected only specific IgG, it was as accurate as the virus-neutralization test for evaluating the immune status of hens to AEV. Moreover, the ELISA was more economical in the use of reagents, time, and personnel and was free from dependence on susceptible embryos. Since ELISAs can be standardized and measured with manual or automated instruments, the derived ELISA can be easily and economically used to evaluate the immune status of breeder hens in commercial poultry operations. 相似文献
77.
Equine neonatal septicaemia was confirmed in 24 foals hospitalised at the Rural Veterinary Centre between 1989 and 1992 with suspected septicaemia. Septicaemia was confirmed by culture of bacteria from blood of live foals and tissues obtained at necropsy of foals that died or were euthanased. Pathogenic bacteria isolated were predominantly Enterobacteriaceae (including Escherichia coli and Salmonella serovars) and Actinobacillus equuli. Clinical manifestations of septicaemia included signs of depression, dehydration, abnormalities in body temperature and manifestations of localised infection including diarrhoea, pneumonia, and septic arthritis. Most common haemato-logical abnormalities were neutropenia and increase of circulating band neutrophils. Survival rate of foals with confirmed septicaemia was 70.8%. Survival was found to be less likely in the presence of pneumonia, severe signs of depression, marked haematological changes or septic arthritis at the time of admission. Seven foals were confirmed to have septic arthritis without concurrent septicaemia. Of these, 4 had multiple joint involvement. Bacteria isolated from infected joints were predominantly Salmonella serovars. Four foals with septic arthritis failed to survive, due to multiple joint infection, which was unresponsive to treatment. The clinical and haematological abnormalities present in foals with confirmed septicaemia and septic arthritis were consistent with those observed in other studies. The bacterial isolates from foals with confirmed septicaemia were similar to those isolated in other studies. In contrast, the bacteria isolated from foals with septic arthritis without concurrent septicaemia were different from other studies. 相似文献
78.
Uterine secretory alterations coincident with embryonic mortality in the gilt after exogenous estrogen administration 总被引:1,自引:0,他引:1
Sixteen crossbred gilts were assigned randomly to receive either an i.m. injection of sesame oil (control) or estrogen (E), 5 mg of estradiol valerate, on d 9 and 10 of pregnancy. Gilts were unilaterally hysterectomized on either d 12 and 14 or 16 and 18. Uterine horns were flushed with 20 ml of .9% sterile NaCl solution to recover conceptus tissue. Conceptuses and endometrial explants were cultured for 24 h with 100 microCi [3H] leucine in 15 ml of minimum essential media. After dialysis, culture media were submitted to 2D-polyacrylamide gel electrophoresis and incorporated proteins were analyzed by fluorography. Normal, intact conceptus tissue was recovered from control gilts. Estrogen-treated gilts flushed on d 12 and 14 contained intact conceptuses; however, uteri from two gilts on d 16 and three on d 18 contained degenerating conceptus tissue. Comparison of endometrial polypeptides synthesized in vitro indicated an alteration in E-treated gilts on d 12 through 18. Although similar polypeptides were present, a band of polypeptides with a Mr of approximately 30,000 and pI from 7.9 to 8.9 and a larger, acidic polypeptide (Mr = 100,000, pI 3.5 to 5.0) were faint or absent in E-treated gilts. Conceptuses elongated normally in the altered uterine environment, but failed to survive past d 14 in E-treated gilts. Although loss of specific polypeptides in E-treated gilts coincides with conceptus death, their function in conceptus development or attachment is unknown. 相似文献
79.
80.
Effects of Growth Hormone on In Situ Culture of Bovine Preantral Follicles are Dose Dependent
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CR Jimenez JL de Azevedo RG Silveira J Penitente‐Filho EL Carrascal‐Triana AM Zolini VR Araújo CAA Torres 《Reproduction in domestic animals》2016,51(4):575-584
The objective of this study was to evaluate different concentrations of growth hormone (GH) on the development of bovine preantral follicles cultured included in the ovarian tissue (in situ) on the rates of morphologically normal, viable, primordial and developing follicles, as well as the oocyte and follicle diameter and ultrastructural analysis. Ovarian fragments collected from cows with no cross‐breeds defined were cultured in situ for 1 and 7 days in minimal essential medium (α‐MEM+) supplemented with different concentrations of recombinant human GH (0, 10, 25, 50 ng/ml). The ovarian fragments non‐cultured (control) and cultured were processed for classic histology, mechanical isolation and electron transmission microscopy (MET). The parameters underwent anova (Tukey′s and Dunnett′s tests) and chi‐square test (χ2). After 7 days of culture, the treatment with 50 ng/ml GH showed no differences with fresh control (p > 0.05) and had greater effectiveness than in the 0, 10 and 25 ng/ml GH concentrations of the morphologically normal follicles. Regarding the primordial follicles, a reduction was observed in the 50 ng/ml GH concentration concomitant with the significant increase in developing follicles, differing from both the fresh control and the other GH concentrations tested. In addition, 50 ng/ml GH showed a larger follicle and oocyte diameter when compared to the other treatments cultured. Similar structures were ultrastructurally observed in the control group, 50 ng/ml GH. Follicles cultured in 10 ng/ml GH showed nuclear invagination, vacuoles and lesioned basal membrane. Hence, it is concluded that 50 ng/ml GH is the most effective concentration for the development of preantral follicles cultured in situ. 相似文献