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71.
A field grazing trial was undertaken to monitor the health and production of crossbred sheep grazing pasture where Echium plantagineum constituted a considerable proportion of the available forage. The trial, conducted for 19 months over successive grazing seasons, demonstrated a significant difference in production, with sheep on the E. plantagineum pasture being lighter and growing less wool compared with sheep on Echium-free pasture. No mortalities involving pyrrolizidine alkaloid poisoning were recorded in sheep grazing E. plantagineum, although there was histological evidence of moderately severe liver damage associated with high liver copper concentrations in at least one sheep following the grazing of large quantities of the plant.  相似文献   
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Two dogs with tumors in the left nasal vestibule were treated by surgical excision of the affected part of the nose. Radiation and chemopotentiation were used in one dog, which remained tumor-free after 12 months. When recovering from anesthesia, the second dog developed respiratory distress associated with upper airway obstruction and failure to mouth breathe. The dog was successfully treated by temporary tracheostomy and remained tumor-free after 3 months. Surgery preserved the function of the right nostril and gave an acceptable cosmetic result in both cases.  相似文献   
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In six normal adult horses, pulsed-wave Doppler sonographic inspections were made of the left and right lateral palmar proper digital artery (LPPDA) of each thoracic limb. Using a two-period, crossover design with repeated measures, each LPPDA was inspected on four occasions throughout the day over a 7 hour period and, on each occasion, with the limb weight bearing and non-weight bearing. In comparison with the observations made during weight bearing, there were significant increases (P<0.001) in blood-flow velocities when the limb was non-weight bearing. There was no relationship between blood velocities and the time of day, the order in which the inspections were made, resting heart rate, age of the horse, or hoof angle. In both weight bearing and nonweight bearing, the Doppler waveform demonstrated a systolic peak followed by at least two diastolic peaks and an end diastolic plateau. Horses that moved least during sonographic inspections had the lowest co-efficients variation.  相似文献   
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Premature farrowings caused by feeding cottonseed meal   总被引:1,自引:0,他引:1  
Increasing the level of cottonseed meal (CSM) in sow diets from less than 5% to 10% increased the incidence of premature farrowings (gestation length less than 111 days) from 1.1% to 2.7% (p less than 0.001) and reduced the mean gestation length from 114.07 +/- 1.53 to 113.70 +/- 1.59 days (p less than 0.0001). Survival of piglets born prematurely was poor. After removal of CSM from the diet there was a residual effect lasting several weeks before the gestation length returned to normal. Experimental feeding of diets containing 20% and 40% CSM to small groups of sows caused significant shortening of gestation length and 3 of 26 sows fed 40% CSM farrowed prematurely. The mechanism by which CSM causes this effect has yet to be determined.  相似文献   
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Two outbreaks of photosensitivity and jaundice in sheep grazing the grass, Brachiaria decumbens. In West Java in 1983 and 1983 and 1990 are described. Aggregates of acicular clefts and crystals were present in bile canaliculi, bile ducts, Kupffer cells, hepatocytes and in kidney tubules. The number of crystals increased with the length of exposure to the plant and sheep that died had the largest accumulations. These crystalline structures have been reported before in this syndrome, but are similar to those seen in Tribulus terrestris and Panicum spp toxicities.  相似文献   
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Due to its high vapor pressure and low boiling point, desflurane requires a specially designed, electronically controlled, temperature and pressure compensated vaporizer to regulate agent delivery to the anesthetic circuit. However, if the vapor pressure and boiling point were decreased, desflurane could be used in any conventional variable bypass vaporizer. Raoult's Law states that the vapor pressure of a liquid is proportional to its molar fraction in a solution. Accordingly, propylene glycol was used as a solvent for desflurane, and the physical characteristics of this mixture were evaluated at various molar concentrations and temperatures. Desflurane boiling point increased and vapor pressure decreased as a nonlinear function of dilution, but these changes were less than predicted by Raoult's Law. Using a circle system with a breathing bag attached at the patient end and a mechanical ventilator to simulate respiration, an in‐circuit, nonprecision vaporizer containing 40% desflurane and 60% propylene glycol achieved a 11.5 ± 1.0% (mean ± SD) circuit desflurane concentration with a 5.2 ± 0.4 (0 = off, 10 = maximum) vaporizer setting. This experiment was repeated with a dog attached to the breathing circuit under spontaneous ventilation with a fresh gas flow of 0.5 L min–1. Anesthesia was maintained for over two hours at a mean vaporizer setting of 6.2 ± 0.4, yielding mean inspired and end‐tidal desflurane concentrations of 8.7 ± 0.5% and 7.9 ± 0.7%, respectively. Within 5 minutes after cessation of anesthesia, the dog was awake, extubated and standing. In clinical practice, propylene glycol may not prove an ideal solvent for desflurane due to its instability in solution and substantial positive deviation from Raoult's Law. However, rather than alter the vaporizer to suit physical properties of anesthetic agents, this study demonstrates that it may also be possible to alter anesthetic agents to suit physical properties of the vaporizer.  相似文献   
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