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41.
Sixty-eight cases of uterine prolapase in pastured dairy cows were treated in 2 consecutive spring calving seasons in East Gippsland, Victoria. Fifty cows survived (73.5%). Of 43 cows available for followup, 36 (84%) conceived in the mating period following the prolapse, taking 10 d longer to conceive than herd mates that calved on the same day. Three of the 36 cows (8%) that conceived, aborted, this occurring in the middle trimester of pregnancy. No prolapses occurred at the following calving but one case had suffered uterine prolapse 2 years previously. The conclusions drawn from these observations are that cows with uterine prolapse have a good chance of surviving if treated, that treatment is cost-effective, that uterine prolapse is unlikely to reoccur and treated cows have a good chance of conceiving. The veterinarians involved in this investigation were reasonably accurate in their ability to predict long term survival but not as good in predicting ability to conceive again.  相似文献   
42.
The refinement of anaesthetic regimes is central to improving the welfare of captured wildlife. The Eurasian badger (Meles meles) has been the subject of an intensive long-term ecological and epidemiological study at Woodchester Park, Gloucestershire, England. During routine trapping operations (June 21st, 2000-January 23rd, 2001) an experimental trial was conducted on 89 badgers to compare the physiological effects of anaesthesia using ketamine hydrochloride alone, and in conjunction with medetomidine hydrochloride and butorphanol tartrate. The mixture induced a significantly longer period of anaesthesia, and either substantially reduced or eliminated the adverse effects associated with ketamine anaesthesia (e.g., excessive salivation, bouts of sneezing, rough recoveries, and muscle rigidity). In a sub-sample of badgers given the mixture, anaesthesia was reversed using atipamezole hydrochloride. Under ketamine anaesthesia, heart rates were initially significantly higher and respiration rates were consistently higher, than in badgers given the mixture. In all badgers heart rates declined and respiration rates increased during anaesthesia, but the rate of change was greatest in animals given only ketamine. Overall, the mixture provided a more balanced anaesthesia characterised by muscle relaxation and complete unconsciousness.  相似文献   
43.
Severe digoxin toxicosis in a 13-year-old mixed-breed dog with dilated cardiomyopathy was successfully treated with i.v. administration of ovine digoxin-specific IgG Fab fragments. Management of this dog following treatment with Fab fragments was complicated by hypomagnesemia and loss of the positive inotropic effect of digoxin.  相似文献   
44.
Hematuria indicates the presence of urogenital disease in dogs and cats. Persistent hematuria (macroscopic or microscopic) should be evaluated to determine the source of bleeding and the underlying cause so that appropriate treatment can be recommended. Results of the history and physical examination often help to localize disease to the urinary tract (either upper or lower) or genital tract.Additional diagnostic evaluation, including laboratory testing(eg, urinalysis, urine culture), diagnostic imaging (eg, abdominal radiographs, ultrasound), and collection of tissues for cytologic or histopathologic evaluation, may be needed to identify the underlying cause. If a thorough evaluation fails to reveal the source or cause of hematuria, exploratory celiotomy should be considered,especially if idiopathic renal hematuria is possible.  相似文献   
45.
Hypercalcemia secondary to cholecalciferol rodenticide toxicosis was identified in two dogs. The first dog died shortly after admission. The second dog responded to treatment with sodium chloride solution, prednisolone, furosemide, and calcitonin. Treatment was needed for a longer period than anticipated and the serum calcium concentration did not stabilize for approximately one month. Although not conclusively demonstrated, calcitonin was considered the cause of severe anorexia. This new class of rodenticides has great toxic potential for dogs, and it is recommended that serum calcium concentration be carefully monitored as treatment for hypercalcemia is gradually withdrawn.  相似文献   
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47.
In contrast to other kinds of phospholipases, phospholipases D that are toxic for humans and animals are not commonly encountered as constituents of venoms or as products of pathogenic microorganisms. Toxic phospholipases D are present, however, in the venom of the brown recluse spider (Loxosceles reclusa) and in supernatants or filtrates of cultures of Corynebacterium pseudotuberculosis. Although the two enzyme toxins are derived from phylogenetically disparate entities, they are similar in molecular weight, charge, substrate specificity, and in several biological activities. They are immunologically distinguishable.  相似文献   
48.
The transition metal chalcogenide Ni(S,Se)2 is one of the few highly correlated, Mott-Hubbard systems without a strong first-order structural distortion that normally cuts off the critical behavior at the metal-insulator transition. The zero-temperature (T) transition was tuned with pressure, and significant deviations were found near the quantum critical point from the usual T1/2 behavior of the conductivity characteristic of electron-electron interactions in the presence of disorder. The transport data for pressure and temperature below 1 kelvin could be collapsed onto a universal scaling curve.  相似文献   
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50.
Establishing the competitive relationships at the local neighbourhood level is essential for improving our understanding of tree growth dynamics in structurally heterogeneous and species-rich forests. We studied the competitive interactions influencing individual-tree five-year radial growth of the two species Castanopsis fargesii (Franch.) and Quercus fabri (Hance) in a diverse young secondary evergreen broad-leaved forest (EBLF) in eastern China. Different spatially explicit individual-based competition indices were examined for their effectiveness at predicting radial growth. These indices were based on one of the three tree size variables - diameter at breast height (dbh), total height, and crown projection area - and were combined with different approaches to identify potential competitors. Furthermore, we tested for competitive equivalence of conspecific and heterospecific neighbours and analysed the effects of local diversity, initial dbh (measured at the beginning of the five-year growth period) and abiotic environmental variables on individual-tree radial growth. Competition accounted for up to 78% and 75% of radial growth variation in C. fargesii and Q. fabri, respectively. The best results were provided by competition indices using crown projection area as the variable describing tree size and the angular height method as the approach to identify potential competitors (i.e. neighbours greater than the minimum angular height, measured from the base of the target trees, are selected as competitors). Competitive equivalence of conspecific and heterospecific neighbours was found in C. fargesii, whereas heterospecifics were stronger competitors than conspecifics in Q. fabri. We could not detect diversity effects on radial growth. The addition of initial dbh or abiotic environmental variables as further explanatory variables failed to improve the predictive ability of growth models. Our results indicate that diameter growth in this EBLF is largely a function of local neighbourhood competition and suggest that the mode of competition is primarily size-asymmetric. It appears that there may be high competitive equivalence among different species, but this remains to be experimentally tested.  相似文献   
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