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121.
de la Calle J Burba DJ Ramaswamy CM Hosgood G Williams J LeBlanc C Moore RM 《American journal of veterinary research》2002,63(12):1648-1654
OBJECTIVE: To compare plasma and synovial fluid endothelin-1 (ET-1) and nitric oxide (NO) concentrations in clinically normal horses and horses with joint disease. ANIMALS: 36 horses with joint disease, and 15 horses without joint disease. PROCEDURE: Horses with joint disease were assigned to 1 of the 3 groups (ie, synovitis, degenerative joint disease [DJD], or joint sepsis groups) on the basis of findings on clinical and radiographic examination and synovial fluid analysis. Endothelin-1 and NO concentrations were measured in plasma from blood samples, collected from the jugular vein and ipsilateral cephalic or saphenous vein of the limb with an affected or unaffected joint, as well as in synovial fluid samples obtained via arthrocentesis from the involved joint. RESULTS: Plasma ET-1 concentrations between affected and unaffected groups were not significantly different. Median concentration and concentration range of ET-1 in synovial fluid obtained from the joint sepsis group (35.830 pg/mL, 7926 to 86.614 pg/mL; n = 7) were significantly greater than values from the synovitis (17.531 pg/mL, 0.01 to 46.908 pg/mL; 18), DJD (22.858 pg/mL, 0.01 to 49.990 pg/mL; 10), and unaffected (10.547 pg/mL, 0.01 to 35.927 pg/mL; 10) groups. Plasma and synovial fluid NO concentrations between affected and unaffected groups were not significantly different. CONCLUSIONS AND CLINICAL RELEVANCE: Endothelin-1 is locally synthesized in the joints of horses with various types of joint disease. Synovial fluid concentrations of ET-1 varied among horses with joint disease, with concentrations significantly higher in the synovial fluid of horses with joint sepsis. These results indicate that ET-1 may play a role in the pathophysiologic mechanism of joint disease in horses. 相似文献
122.
Winchell WW Hardy J Levine DM Parker TS Gordon BR Saal SD 《American journal of veterinary research》2002,63(10):1370-1378
OBJECTIVE: To evaluate the effect of a phospholipid emulsion (PLE) on the initial response of horses to administration of endotoxin. ANIMALS: 12 healthy adult horses. PROCEDURES: Horses were assigned to 2 treatment groups (6 horses/group). The control group was administered 1 L of saline (0.9% NaCl) solution, and the treated group was administered PLE (200 mg/kg, IV); treatments were administered during a period of 120 minutes. An infusion of endotoxin was initiated in both groups starting 1 hour after initiation of the saline or PLE solutions. Physical examination and hemodynamic variables were recorded, and blood samples were analyzed for concentrations of tumor necrosis factor (TNF)-alpha, interleukin-6, thromboxane B2 (TxB2), 6 keto-prostaglandin F (PGF)1alpha, total leukocyte count, and PLE concentrations. An ANOVA was used to detect significant differences. RESULTS: Administration of PLE resulted in significantly lower rectal temperature, heart rate, cardiac output, right atrial pressure, and pulmonary artery pressure and higher total leukocyte counts in treated horses, compared with values for control horses. The TNF-alpha concentration was significantly less in treated horses than in control horses. The TxB2 and 6 keto-PGFF1alpha concentrations were significantly different between treated and control horses at 30 minutes (TxB2) and at 30 and 60 minutes (6 keto-PGF1alpha). CONCLUSIONS AND CLINICAL RELEVANCE: Prior infusion of PLE in horses administered a low dose of endotoxin decreased rectal temperature, heart rate, pulmonary artery pressure, and TNF-alpha concentrations. Results of this study support further evaluation of PLE for use in the treatment of horses with endotoxemia. 相似文献
123.
Effect of lameness on milk yield in dairy cows 总被引:1,自引:0,他引:1
Hernandez J Shearer JK Webb DW 《Journal of the American Veterinary Medical Association》2002,220(5):640-644
OBJECTIVE: To examine the relationship between lameness and milk yield in dairy cows. DESIGN: Cohort study. ANIMALS: 531 dairy cows. PROCEDURE: Cows affected with lameness were classified into 1 of 3 groups on the basis of type of diseases or lesions observed, including interdigital phlegmon (foot rot), papillomatous digital dermatitis (foot warts), or claw lesions. Cows not affected with lameness were classified as healthy. From Dairy Herd Improvement Association records, 305-day mature equivalent milk yield data were collected at the end of lactation or when the cow left the herd. Milk yield was compared between cows affected with lameness and healthy cows. RESULTS: 167 (31%) cows were affected with lameness during lactation. Lame cows had claw lesions (60%), papillomatous digital dermatitis (31%), or interdigital phlegmon (9%). Milk yield in lame cows with interdigital phlegmon (mean, 17,122 lb) was significantly less, compared with healthy cows (19,007 lb). CONCLUSIONS AND CLINICAL RELEVANCE: In this herd, interdigital phlegmon was associated with a 10% decrease in milk production. Lame cows with claw lesions or papillomatous digital dermatitis produced less milk than healthy cows, but the difference was not significant. 相似文献
124.
Buff PR Dodds AC Morrison CD Whitley NC McFadin EL Daniel JA Djiane J Keisler DH 《Journal of animal science》2002,80(11):2942-2948
Obesity has been a major concern in the horse industry for many years, and the recent discovery of leptin and leptin receptors in numerous nonequine species has provided a basis for new approaches to study this problem in equine. The objectives were to: 1) clone a partial sequence ofthe equine leptin and leptin receptor genes so as to enable the design of primers for RT-PCR determination of leptin and leptin receptor gene presence and distribution in tissues, 2) develop a radioimmunoassay to quantify peripheral concentrations of leptin in equine, 3) determine if peripheral concentrations of leptin correlate with body condition scores in equine, and 4) determine if changing body condition scores would influence peripheral concentrations of leptin in equine. In Experiment 1, equine leptin (GenBank accession number AF179275) and the long-form of the equine leptin receptor (GenBank accession number AF139663) genes were partially sequenced. Equine leptin receptor mRNA was detected in liver, lung, testis, ovary, choroid plexus, hypothalamus, and subcutaneous adipose tissues using RT-PCR. In Experiment 2, 71 horses were categorized by gender, age, and body condition score and blood samples were collected. Sera were assayed for leptin using a heterologous leptin radioimmunoassay developed for equine sera. Serum concentrations of leptin increased in horses with body condition score (1 = thin to 9 = fat; r = 0.64; P = 0.0001). Furthermore, serum concentrations of leptin were greater in geldings and stallions than in mares (P = 0.0002), and tended to increase with age of the animal (P = 0.08). In Experiment 3, blood samples, body weights, and body condition scores were collected every 14 d from 18 pony mares assigned to gain or lose weight over a 14-wk interval based on initial body condition score. Although statistical changes (P = 0.001) in body condition scores were achieved, congruent statistical changes in peripheral concentrations of leptin were not observed, likely due to the small range of change that occurred. Nonetheless, serum concentrations of leptin tended to be greater in fat-restricted mares than in thin-supplemented mares (P = 0.09). We conclude that leptin and leptin receptors are present in equine tissues and that peripheral concentrations of leptin reflect a significant influence of fat mass in equine. 相似文献
125.
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127.
Orobanche amethystea Thuill.,O. loricata Reichenb. andO. pubescens D’Urv. were found to parasitize the roots of cultivated plants in Israel.Orobanche pubescens is known from the local flora, and was now found to cause damage in parsley fields and toTropaeolum majus L. (nasturtium) in ornamental gardens.Orobanche amethystea andO. loricata are known as occasional weeds in Europe and were recently found for the first time in Israel.Orobanche amethystea densely populated vetch fields in Israel, andO. loricata was found in ornamental gardens. A key for the identification ofOrobanche species in cultivated areas in Israel is given, based on morphological features.
http://www.phytoparasitica.org posting Jan. 13, 2002. 相似文献
128.
Llewellyn ZN Ou X Chang GJ Schmitt B Salman MD Akkina RK 《American journal of veterinary research》2000,61(11):1358-1363
OBJECTIVE: To compare molecular associations between the vesicular stomatitis virus (VSV)-New Jersey isolates of the 1995 outbreak with those from previous outbreaks between 1982 and 1985 in the western United States. SAMPLE POPULATION: 23 virus isolates considered representative of the 1995 outbreak of vesicular stomatitis. PROCEDURE: Viral gene coding for surface-envelope protein G was evaluated by use of nucleotide sequencing and phylogenetic analysis. RESULTS: Changes in up to 0.77% of the nucleotide bases and 1.35% of the amino acids were detected among the 1995 viral isolates, whereas changes in up to 3.2 and 2.9% of the nucleotides and amino acids, respectively, were found, compared with the 1982 to 1985 viruses. Insertions or deletions were not found in the entire gene, which spanned 1,554 nucleotide bases. CONCLUSIONS AND CLINICAL RELEVANCE: Phylogenetic analysis indicated that the 1995 VSV-New Jersey belongs to a lineage distinct from that of the 1982 to 1985 viruses that caused previous outbreaks in the western United States. Furthermore, it also is distinct from strains from Central America and from the Georgian Hazelhurst strain. 相似文献
129.
In the fall of 1999, West Nile virus (WNV) was isolated for the first time in the Western Hemisphere during an outbreak of neurologic disease in humans, horses, and wild and zoo birds in the northeastern United States. Chickens are a potential reservoir for WNV, and little is known about the pathogenicity of WNV in domestic chickens. Seven-week-old chickens derived from a specific-pathogen-free flock were inoculated subcutaneously with 1.8 x 10(3) 50% tissue culture infectious dose of a crow isolate of WNV in order to observe clinical signs and evaluate the viremic phase, gross and microscopic lesions, contact transmission, and immunologic response. There were no observable clinical signs in the WNV-inoculated chickens during the 21-day observation period. However, histopathologic examination of tissues revealed myocardial necrosis, nephritis, and pneumonitis at 5 and 10 days postinoculation (DPI); moderate to severe nonsuppurative encephalitis also was observed in brain tissue from one of four inoculated birds examined at 21 DPI. WNV was recovered from blood plasma for up to 8 DPI. Virus titers as high as 10(5)/ml in plasma were observed at 4 DPI. Fecal shedding of virus was detected in cloacal swabs on 4 and 5 DPI only. The WNV also was isolated from myocardium, spleen, kidney, lung, and intestine collected from chickens euthanatized at 3, 5, and 10 DPI. No virus was isolated from inoculated chickens after 10 DPI. Antibodies specific to WNV were detected in inoculated chickens as early as 5 DPI by the plaque reduction neutralization test and 7 DPI by the indirect fluorescent antibody test. Chickens placed in contact with inoculated chickens at 1 DPI lacked WNV-specific antibodies, and no WNV was isolated from their blood plasma or cloacal swabs throughout the 21 days of the experiment. 相似文献
130.
Zimmerman KL Bender HS Boon GD Prater MR Thorn CE Prater D Robertson JL Saunders GK Sponenberg DP Inzana KD Lanz OI Wright E 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2000,29(1):29-34
Abstract: The cytologic and histologic features of 2 intracranial and 2 spinal (extramedullary cervical) canine meningiomas were compared. Cerebrospinal fluid analysis in 2 cases revealed mild, mixed cell pleocytosis, primarily composed of small lymphocytes and monocytoid cells, with a moderate increase in total protein concentration. Cytologic features suggestive of meningioma included cells with both epithelial and mes-enchymal characteristics and a tendency towards cell clustering. Tumor location also was useful in making a diagnosis. The 4 meningiomas differed histologically from one another, and included angioblastic, psam-momatous, meningotheliomatous, and microcystic anaplastic types, which conformed to a classification scheme for human meningiomas. The classification scheme could not be applied to cytologic specimens. 相似文献