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The anesthetic and cardiorespiratory effects of a low dose (LD, 0.4 mg kg?1 xylazine and 4 mg kg?1 ketamine) and a high dose (HD, 0.8 mg kg?1 xylazine and 8 mg kg?1 ketamine) of IM xylazine–ketamine combination were compared in a randomized cross‐over study using six castrated male llamas. Three llamas in each dosage group (LDT, HDT) were assigned to receive IM tolazoline (2 mg kg?1) after 30 minutes of recumbency. All IM injections were given in the semitendinosus or semimembranosus muscles. Pulse, respiratory rate, and indirect arterial blood pressure were recorded every 10 minutes, and hemoglobin oxygen saturation was recorded every 5 minutes during lateral recumbency. Samples for arterial blood gas analysis were collected 5 minutes following recumbency and every 30 minutes thereafter. Base‐to‐apex ECG was monitored continuously. Analgesia was evaluated every 5 minutes by both a 30 minutes skin pinch and a needle prick of the toe. Most llamas breathed room air throughout anesthesia. Two llamas that developed severe hypoxemia (SpO2 < 75%) received 5 minutes of nasal oxygen insufflation, but were maintained on room air for the rest of the anesthetic period. anova for repeated measures and Tukey's test were used to analyze cardiorespiratory data. Fischer's exact test was used to compare the ability of each to provide >30 minutes of lateral recumbency and analgesia. A p‐value < 0.05 was considered significant. Both dosages provided reasonably rapid induction following injection (LD: 10.8 ± 6.3 minutes; HD: 5.0 ± 1.1 minutes; p = 0.07). Duration of lateral recumbency and analgesia were 34.7 ± 6.7 and 27.3 ± 4.6 minutes, respectively, in the LDT llamas. None of the three remaining LD llamas remained in lateral recumbency for longer than 12 minutes. Duration of lateral recumbency and analgesia were 87.3 ± 18.5 and 67.7 ± 16.0 minutes, respectively, for the HD llamas that did not receive tolazoline. The HDT llamas were recumbent for a significantly shorter time (43.3 ± 0.6 minutes; p = 0.05). The ability to provide >30 minutes of recumbency and analgesia was better in the HD group (6/6) than in the LD group (2/6) (p = 0.03). No differences between dosages were seen in pulse rate, respiratory rate, or arterial pressures. No ECG abnormalities were seen. Transient hypoxemia was seen in the first 10 minutes of lateral recumbency in the HD group by both hemoglobin oxygen saturation (84 ± 9.5%) and by blood gas PaO2 (44.5 ± 5.8 mm Hg). It was concluded that the HD provided more consistent results than the LD, but induced transient hypoxemia. Tolazoline shortened the recovery time in llamas receiving the HD.  相似文献   
23.
The aim of this study was to investigate if farmer awareness of longevity can explain why the longevity of dairy cows does not increase in Sweden, despite the fact that the genetic trend for longevity in Swedish dairy cattle is positive. In this study, farmers’ decisions were put in the forefront through a qualitative study with semi-structured interviews. The results showed that farmers seemed well aware of biological factors related to cow longevity, that they think the demands on dairy cows have increased over time and that they correlate the higher demands to shorter longevity. However, the farmers had not worked explicitly with longevity of their own herd. There are subjective management decisions behind a culling of a dairy cow, and the reporting of culling reasons does not mirror the farmer’s reasoning behind the decisions, which is a key factor determining longevity.  相似文献   
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An 8-year-old, castrated male, miniature wire-haired dachshund was presented with a 4-month history of intermittent facial twitching (myoclonus). The myoclonic episodes progressed over a 16-month period. Generalized seizure activity was infrequent. Clinical examination revealed visually stimulated myoclonus. Response to therapy with antiepileptic drugs was equivocal. Genetic testing identified the dog as being affected by Lafora disease.  相似文献   
26.
The objective of this clinical trial was to examine the effect of a single dose of florfenicol on antimicrobial resistance patterns in faecal E. coli of feedlot steers. Steers (n = 370), were purchased from two sources and housed in outdoor concrete floored pens. Two cattle from each pen (n = 42 pens, 84 cattle) were randomly selected for faecal sampling at study day 1, 14, 28, and 42. One sampled animal from each of 21 pens was randomly selected to receive a single 39.6 mg/kg dose of florfenicol subcutaneously at study day 11. Ten lactose positive colonies were isolated from faecal swabs and tested for antimicrobial resistance to 11 antimicrobials using the disk diffusion method. Zones of inhibition were grouped using cluster analysis and clusters were ordered by increasing multiple resistance. A cumulative logistic regression model using generalized estimating equations was used to assess factors associated with increasing levels of multiple resistance. Immediately post-treatment, all isolates obtained from treated cattle belonged to multiple resistant clusters containing chloramphenicol resistance. Though less pronounced in later sampling, resistance to chloramphenicol and other antimicrobials persisted. Antimicrobial treatment, sampling time and animal source, as well as interactions between these variables, were important predictors of the odds of E. coli belonging to a more resistant cluster. A very clear but transitory shift to increasingly multiple resistant faecal E. coli in response to florfenicol treatment was observed. There was no indication of horizontal transfer of resistant E. coli between steers. Level of resistance was influenced by complex interaction of animal source and previous management.  相似文献   
27.
The influence of zinc bacitracin (ZB) and of Bacillus licheniformis on host microbial-related functions in young piglets was investigated by applying the concept of microflora-associated characteristics. Six biochemical parameters were determined before and after weaning in faecal samples from piglets in four litters having access to a diet containing ZB, to a diet containing B. licheniformis, to a diet with both additives, or to a diet with no additives, from 3 weeks of age. Statistically significant differences were found in three of the intestinal functions investigated: formation of short-chain fatty acids (at 7 and 10 weeks of age), degradation of mucin (at 7 and 10 weeks of age) and conversion of bilirubin to urobilins (at 7 weeks of age). We also found age-dependent influences on the formation of short-chain fatty acids, on conversion of cholesterol to coprostanol and on conversion of bilirubin to urobilins. We conclude that a functional approach is appropriate for measuring exogenous influence(s) on the microbial intestinal metabolisms in weaned piglets.  相似文献   
28.
Cerebrospinal angiostrongyliasis in five captive tamarins (Sanguinus spp)   总被引:1,自引:0,他引:1  
Four cotton-top tamarins ( Sanguinus oedipus oedipus ) and one emperor tamarin ( S imperator subgrisescens ) housed in a zoo became depressed, anorexic, paraparetic and eventually paralysed. The animals died within 5 days to 18 months of the appearance of clinical signs. Histological examination showed nonsuppurative and eosinophilic meningoencephalitis, and metastrongyle nematode larvae were found within subarachnoid spaces of all animals and within the spinal cord of one. Intact larvae with features consistent with Angiostrongylus cantonensis were recovered from the brain of one animal. This parasite is the classical cause of eosinophilic meningoencephalitis in many parts of the world and the diagnosis can be strongly suspected on clinical grounds. In endemic areas like south-east Queensland, protection of captive animals against infection with A cantonensisi s a difficult balance between providing a stimulating, natural setting and eliminating potentially infectious definitive, intermediate and paratenic hosts… This is the first report of cerebrospinal angiostrongyliasis in tamarins and nonhuman primates in Australia.  相似文献   
29.
Zusammenfassung Im Gegensatz zu unsichtbaren Immissionen gibt es keine unsichtbaren Immissionssch?den, wenn man berü cksichtigt, da? physikalische, chemische und botanische Untersuchungen neben Aufwuchs- und Ertragsermittlungen, die sich dem blo?en Auge verschlie?enden Sch?den erkennbar machen.
Summary Contrary to invisible immissions there are not invisible injuries caused by immissions. Physical, chemical and botanic tests as well as examinations into growth and produce make injuries perceptible which are invisible for eyes.


5628 Heiligenhaus (Bez. Düsseldorf), Beethovenstra?e 42  相似文献   
30.
The authors evaluated the cell growth inhibition, reduction of tumourigenicity, and differentiation-inducing effects of sodium phenylacetate (NaPA) on a canine mammary tumour cell line. Treatment of the canine mammary tumour cell line (MCM-B2) with NaPA lead to the arrest of cell growth. Sodium phenylacetate induced changes in the cells to non-malignant characteristics, as indicated by a reduction of colony formation in semi-solid agar and a decrease in tumour formation in athymic mice. Moreover, NaPA induced morphological changes from a spindle-shaped to an epithelial-like appearance, and significant accumulation of lipid droplets in the cytoplasm. Immunohistochemically, these treated cells reacted clearly with the antibody for keratin/cytokeratin. Sodium phenylacetate treatment increased the expression of the milk-specific genes alpha-lactalbumin and beta-casein. The results of this study warrant an evaluation of NaPA in a clinical trial to establish its possible value as adjunctive treatment of malignant canine mammary tumours.  相似文献   
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