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81.
Contrast radiography (barium sulphate suspension fed by stomach tube) was used to assess abomasal profile area (a reflection of tone in the abomasal wall) and the rate of abomasal emptying in healthy lambs aged four to 144 hours and in lambs affected by watery mouth. In healthy lambs abomasal profile area increased from 15.1 +/- 0.56 cm2/kg at four hours of age to 23.1 +/- 1.07 cm2/kg at 24 to 48 hours (P less than 0.001). There was no change up to 48 to 72 hours but after this age there was a substantial decrease to 12.8 +/- 0.76 cm2/kg at 120 to 144 hours (P less than 0.001). The rate of abomasal emptying decreased as abomasal profile area increased. Complete emptying of the abomasum was observed within three hours of feeding in the majority of lambs aged four hours (seven out of eight) and 120 to 144 hours (13 out of 16) but only in a minority of lambs aged 24 to 48 hours (one out of 11). In lambs affected by watery mouth (mean age [+/- se] 33 +/- 2.8 hours, n = 34) abomasal profile area was greater and the rate of abomasal emptying was slower than in healthy lambs aged 24 to 48 hours. These findings confirm the previous suspicion that watery mouth is associated with an impairment of gut motility. Abomasal emptying time was prolonged in lambs aged four hours when either ewe or cow colostrum was included with the contrast medium. A similar effect was observed in lambs aged 24 to 48 hours when cow colostrum was included. The castration of lambs aged four hours with rubber rings immediately before the administration of contrast medium had no effect on the rate of abomasal emptying. 相似文献
82.
A field investigation of causes of abortion in dairy cattle 总被引:2,自引:0,他引:2
R D Murray 《The Veterinary record》1990,127(22):543-547
Cases of abortion on dairy farms on the Lancashire/Cumbria border were investigated by means of a systematic diagnostic procedure, using the facilities of a veterinary practice's laboratory, and the Ministry of Agriculture, Fisheries and Food veterinary investigation centre. Among approximately 3600 animals, 149 abortions were investigated on 54 farms in two years, an annual abortion rate of 2 per cent. A diagnosis was made in 34 per cent of the cases, based on a pathological examination of aborted material and bacteriological and serological findings. The most common pathogens associated with abortion were bovine viral diarrhoea virus (39 cases), bacterial or fungal infections (20 cases), infectious bovine rhinotracheitis virus (19 cases), and Leptospira hardjo (18 cases), either as single or multiple infections. 相似文献
83.
84.
Kendall S Frazier Charles A Baldwin Mel Pence Joe West John Bernard Alan Liggett Debra Miller Murray E Hines 《Journal of veterinary diagnostic investigation》2002,14(6):457-462
Sixty-eight cases of suppurative, ulcerative endometritis associated with Bovine Herpesvirus-4 (BHV-4) in postparturient dairy cows (62 Holsteins and 6 Jerseys, mean age 4.2 years) were confirmed by a combination of histopathology, fluorescent antibody assays, electron microscopic evaluation of uterus, and polymerase chain reaction (PCR). All cases occurred in the 3- to 28-day postpartum period, and histologic lesions among various cows were consistent when compared with postpartum interval. The endometrial lining epithelium was necrotic and ulcerated from 3 to 7 days postpartum, with only mild inflammation in the lamina propria and submucosa. From 1 to 4 weeks postpartum, the ulcers were confluent to diffuse. Epithelium was replaced by fibrinonecrotic, suppurative mats, resulting in severe bacterial pyometra by day 24. Seroprevalence to BHV-4 in one dairy with a history of 18 mortality cases was 36% (107 of 296). In a random sample of 8 cows from this herd, none had serologic titers in blood sampled 2 weeks prepartum, but 3 of 8 seroconverted with significant titers of 1:8 to 1:16 at 2 weeks postpartum. By 10 weeks postpartum, all 8 cows returned to negative serologic status. Two of 6 cats from the premises also had positive titers. Random serum samples taken from 480 dairy cattle at sale barns indicated 76 (16%) were positive by serum neutralization. Clinical signs, postparturient timing, and histologic lesions were very similar to those previously reported in Belgium with BHV-4. But sequence analysis of PCR products of the glycoprotein B region of 4 separate field isolates of endometriotropic BHV-4 suggests these field isolates were more closely related to the North American nonvirulent strain DN-599 than to the endometriotropic European strain V. 相似文献
85.
86.
Michael J. Murray DVM MS D. Michael Cavey Bernard F. Feldman Steven S. Trostle Nathaniel A. White 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(4):199-203
Sympathetic denervation in a 20-year-old, gray, Thorough-bred-Percheron gelding was manifested by cutaneous hyperthermia and sweating over the right side of the body, demarcated by a line from the withers to the elbow and extending cranially. There was cutaneous hyperthermia over the right side of the head, but other signs of Horner's syndrome (sweating, ptosis, miosis, enophthalmos) were not present. The pattern of cutaneous hyperthermia and sweating was consistent with sympathetic denervation localized to the cervicothoracic ganglion, and thoracic radiographs revealed increased density in the craniodorsal thorax. Cytologic evaluation of a sample of pleural effusion revealed mesothelial cells containing melanin and cells suggestive of melanocytes or melanoblasts. Treatment with oral cimetidine and intrapleural cisplatin was not successful. A necropsy was not performed, but the clinical findings supported a diagnosis of thoracic melanoma involving the cervicothoracic ganglion. 相似文献
87.
D H Francis 《Veterinary microbiology》1986,11(1-2):117-123
Various common L-amino acids differed in their ability to suppress K99 production in E. coli. Strains of E. coli also varied in their sensitivity to amino acid-mediated suppression of K99. Alanine, methionine, leucine, and valine were the most suppressive amino acids. However, when compared to single amino acids, mixtures of these amino acids were frequently either less suppressive, non-suppressive, or even stimulatory for K99 expression. 相似文献
88.
White G McClure SR Sifferman R Holste JE Fleishman C Murray MJ Cramer LG 《Journal of the American Veterinary Medical Association》2007,230(11):1680-1682
OBJECTIVE: To determine the effects of 8 days of light to heavy exercise on gastric ulcer development in horses and determine the efficacy of omeprazole paste in preventing gastric ulceration. DESIGN: Randomized, controlled, multicenter clinical trial. ANIMALS: 102 horses with normal-appearing gastric mucosa on endoscopic examination that were in light to heavy training. PROCEDURES: Horses at 4 trial locations were allocated into replicates and sham dosed orally (empty syringe) or treated with a paste formulation of omeprazole (1 mg/kg [0.45 mg/ lb], PO) once daily for 8 days. Training regimens varied among locations and included early training for western performance events; walking, trotting, and cantering in a mechanical exerciser; and race training (2 locations). Prevalences of gastric ulceration at the completion of the 8-day treatment period were compared between groups. RESULTS: At the end of the 8-day treatment period, the proportion of omeprazole-treated horses free from gastric ulceration (88%) was significantly higher than the proportion of sham-dosed horses free from gastric ulceration (27%). CONCLUSIONS AND CLINICAL RELEVANCE: Results showed that horses in light to heavy training for as short as 8 days were at risk of developing gastric ulcers and that administration of omeprazole paste decreased the incidence of gastric ulcers. 相似文献
89.
Aleman M Magdesian KG Peterson TS Galey FD 《Journal of the American Veterinary Medical Association》2007,230(12):1822-1826
CASE DESCRIPTION: A 4-month-old American Paint filly was evaluated because of sudden onset of ataxia that progressed to recumbency. Five additional horses from the same and neighboring premises developed signs of poor performance, generalized weakness, ataxia, and recumbency; 2 of those horses were also evaluated. A new batch of a commercial feed supplement had been introduced to the horses' diet on each farm within the preceding 3 days. CLINICAL FINDINGS: Other than recumbency, findings of physical and neurologic examinations of the foal were unremarkable. The other 2 horses had generalized weakness and mild ataxia, and 1 horse also had persistent tachycardia. The foal had mild leukocytosis with neutrophilia, hyperglycemia, and mildly high serum creatine kinase activity. Results of cervical radiography, CSF analysis, and assessments of heavy metals and selenium concentrations in blood and vitamin E concentration in serum were within reference limits. Feed analysis revealed high concentrations of the ionophore antimicrobial salinomycin. TREATMENT AND OUTCOME: The 5 affected horses survived, but the foal was euthanized. At necropsy, a major histopathologic finding was severe vacuolation within neurons of the dorsal root ganglia, which was compatible with ionophore toxicosis. The surviving horses developed muscle atrophy, persistent weakness, and ataxia. CLINICAL RELEVANCE: In horses, ionophore toxicosis should be considered as a differential diagnosis for acute weakness, ataxia, recumbency, or sudden death. Furthermore, ionophore toxicosis should be considered as a cause of poor performance, weakness, muscle wasting, and cardiac arrhythmias in horses. Surviving horses may have impaired athletic performance. 相似文献
90.
Francis Leo Collins 《Asia Pacific viewpoint》2006,47(2):217-234
Abstract: In recent years, international education has become a source of considerable political, academic and media debate in New Zealand. This is nowhere more the case than with regards to Auckland, the New Zealand city that has hosted the greatest number of international students. This paper focuses on the media debates around international students in Auckland with particular emphasis on the representations of the largest group of international students, those who originate from countries within the North‐East Asian region. The media representations of these students have fixed a diverse group of individuals within a singular racial identity that is known by stereotypical economic, cultural and social characteristics. As a result, these representations have further problematised the interaction between international students and the host population in Auckland while simultaneously implicating a cohort of young New Zealand citizens and permanent residents who are of similar descent within the same discourses. This process of othering the Asian student, regardless of citizenship, has consequences not simply for the practice of exporting education in this city but also for the future of a multicultural Auckland and New Zealand. 相似文献