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T L?ken 《Nordisk veterinaermedicin》1984,36(7-8):259-265
A sample of ergot from meadow grass collected in the south-western part of Norway was examined for alkaloids and dosed orally to four lambs about 10 months old. Sclerotia were dosed at a rate of 0.12-0.75 g per kg body weight per day for 4-27 days. The concentration of total alkaloids in the sclerotia was estimated to be about 0.4%. Ergosine, ergocristine, ergotamine and the three corresponding isomers were identified by thin-layer chromatography. Of the total alkaloids, ergosine and ergocristine constituted 35% each, ergotamine 15% and the isomers 5% each. Three lambs dosed outdoors in cold and wet weather all became ill, with anorexia and increased pulse rate. No symptoms nor post mortem lesions were seen in the single lamb kept indoors. On post mortem examination of the three lambs showing symptoms, hyperemic mucosae, haemorrhages, erosions and necroses in the digestive tract, most pronounced in abomasum and cecum, were demonstrated. In two lambs, slight oedema was found distally in some of the limbs and tail, but no sign of gangrene was observed. 相似文献
23.
Although porcine adenoviruses (PAdV) are present in the swine populations worldwide, they usually do not cause any disease, or the infection is only manifested in a mild diarrhoea or respiratory signs. The importance of adenoviruses, however, is constantly growing as there is a possibility of developing them into viral vector vaccines against more significant swine pathogens. A short summary of the well-established facts of porcine adenoviruses is given and recent developments of the genetic analysis of these viruses are discussed in detail. The possibilities of vector development and examples of vector vaccines already reported in the literature are mentioned. 相似文献
24.
T Miyabayashi D S Biller P A Manley K J Matushek 《Journal of the American Veterinary Medical Association》1991,199(5):598-600
A flexed dorsoplantar radiographic view of the talocrural joint was a useful additional view to diagnose abnormalities of the lateral trochlear ridge of the talus of 2 dogs. This view outlined the subchondral bone of both trochlear ridges of the talus and the apposing cochlea tibiae of the distal portion of the tibia. The tarsus was flexed at the level of the talocrural joint, and an x-ray beam was centered on the joint. With this additional view, fractures of the lateral trochlear ridge were readily diagnosed. This view would help to demonstrate osteochondral lesions of the lateral trochlear ridge. 相似文献
25.
The purpose of this review is to outline and interpret the effects of nutrition, physiological state, sex, genetics, and age on composition of the fat-free dry matter of birds, mammals, and fishes in order to test the hypothesis that the protein:ash ratio in the body is constant. Calculations from a broad array of published data revealed that nutritional factors, including mineral, protein and amino acid nutriture, frequency and level of feeding, and energy intake and nonnutritional factors, including physiological state, sex, genetic background, and age of animal, may each alter the ratio of protein:ash in the body. All or part of the response may be associated with changes in accretion of body protein and(or) skeletal development and mineralization imposed by these nutritional and nonnutritional factors. In most cases of amino acid or protein deficiency, the protein:ash ratio was decreased relative to the control because the deposition of protein in muscle and viscera was reduced more than the growth and mineralization of the skeleton. In other cases, the protein:ash ratio was increased relative to a control because the dietary Ca or P intake or absorption limited skeletal mineralization. More knowledge is needed of how skeletal development and protein:ash ratio in the body is regulated, especially under the influence of nutritional, ontogenetic, and physiological variables among different genotypes of mammals, birds, and fishes. Documentation that the protein:ash ratio in the whole body of representative mammals, birds, and fishes is not constant, but is subject to manipulation, has important physiological and economic implications for developing food animals for the efficient production of lean meat. 相似文献
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Effect of sodium hydroxide treatment on rate of passage and rate of ruminal fiber digestion 总被引:1,自引:0,他引:1
Ruminally fistulated lambs were used to measure the effect of sodium hydroxide treatment on rate of passage and rate of ruminal fiber digestion. Corncobs were raised to 60% moisture and treated to a final concentration of 0, 2.5, 5.0, 7.5 and 10.0% NaOH on a dry matter basis. The diets fed contained 80% cobs and 20% supplement, giving a complete mixed diet containing 0, 2.0, 4.0, 6.0 and 8.0% NaOH (dry basis). Chromic oxide was used as an external marker, and rumen samples were collected at 3, 6, 12, 24, 48 and 96 hr post-dosing. As level of NaOH treatment increased, rate of passage increased linearly (P less than .05). Mean ruminal retention time decreased from 32.4 hr for the control diet to 20.7 hr for the 8% NaOH diet. When rate of passage was regressed against NaOH level, the slope of the line was .142%/hr per unit NaOH, with r2 = .733. In another trial, sodium concentrations equal to the 4% NaOH diet were obtained by the addition of 7.3% NaCl to the basal diet. Rates of passage for lambs fed the diet containing NaCl were faster (P less than .05) than for lambs fed the control diet but slower (P less than .05) than for lambs on the 4% NaOH diet. These data suggest that both sodium intake and NaOH treatment affect rate of passage and are additive. Nylon bags containing .15 g cotton were used to measure the rate of ruminal fiber digestion in lambs fed the five NaOH-treated diets. Bags were removed from the rumen after 12, 24, 36 and 48 hr, and the loss in weight were used to estimate ruminal digestion. As level of NaOH increased, the rate of ruminal cotton digestion decreased linearly (P less than .05). When rate of cotton digestion was regressed against NaOH level, the slope of the line was -.488%/hr per unit NaOH, with r2 = .934. 相似文献
28.
29.
Arthroscopic verification of ultrasonographic diagnosis of meniscal pathology in dogs 总被引:1,自引:0,他引:1
OBJECTIVE: To determine the clinical usefulness of ultrasonography for diagnosis of meniscal pathology in dogs. STUDY DESIGN: Double-blind prospective study. ANIMALS: Dogs (n=10) with lameness localized to the stifle. MATERIALS AND METHODS: Sonographic examination of each affected stifle was performed by 1 ultrasonographer unaware of specific historical and clinical data for the dog. Sonographic findings were recorded, but not reviewed until study completion. Arthroscopic examination of the affected stifle was performed within 48 hours of ultrasonography by 1 surgeon unaware of ultrasonographic findings. Arthroscopic findings were recorded, but not reviewed until study completion. Two investigators compared the ultrasonographic and arthroscopic findings at study completion to determine the sensitivity, specificity, positive predictive value, and negative predictive value. RESULTS: Two of the 10 dogs had bilateral stifle evaluation. Twenty-four lateral and medial menisci, with normal and abnormal findings, were examined. The sensitivity and specificity for ultrasonographic diagnosis were 90.0% and 92.9%, respectively; positive and negative predictive values were 90.0% and 92.9%, respectively. CONCLUSIONS: Ultrasonography is highly specific and sensitive for diagnosing bucket handle tears of the medial meniscus in dogs. CLINICAL RELEVANCE: Ultrasonographic evaluation of menisci in dogs is a noninvasive method for accurately and efficiently diagnosing pathology, determining the need for surgical intervention, and providing comprehensive information to clients. 相似文献
30.