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81.
Fifty-four horses with hoof cracks were referred to the Equine Hospital of the University of Zurich, for treatment. The horses were admitted because of lameness or other symptoms caused by the cracks. Deep or complicated quarter cracks were the most common type of cracks diagnosed. Poor conformation and abnormal hoof shape were the most important causes of hoof crack development, whereas injury to the coronary band was a less frequently encountered cause. Effective treatment of this problem includes corrective shoeing, removing horn from the weight-bearing surface as well as from the crack with a Dremel tool and immobilization of the borders of the crack. However, even with such a therapy, the recurrence rate of hoof cracks was with 20% very high.  相似文献   
82.
To correctly shoe a horse requires the farriers to have a good working knowledge of postural anomalies and movement patterns, as well as of the different concepts of horseshoeing and to be able to apply the appropriate technique to every individual horse they shoe. The correct technique for specific problem cases is frequently a subject of debate amongst specialists and many theories would benefit from objective gait analyses. The case study presented examines the influence of different shoeing conditions on selected gait analysis parameters. The measurements were conducted on a Warmblood mare: (A) shod with long toes, (B) properly trimmed without shoes, (C) conventionally shod with rolled toes and finally (D) shod using the 4-point technique. Data on force-, time- and distance parameters were recorded using an instrumented treadmill. First contact and breakover of the hooves were documented using high-speed videography. A long toe resulted in a prolongation of the breakover time and, therefore, in a prolongation of the second half of the stance phase. Additionally, the prolonged stance duration associated with an unaltered force impulse, led to decreased force peaks. It was possible to objectively record differences between the trimmed, unshod foot, the shod long-toe and the shod rolled toe configurations. The differences between the rolled toe and the 4 point shoe however, were minimal. Gait analysis is a technique well suited for objective evaluation of different shoeing techniques under standardised conditions.  相似文献   
83.
84.
The nonvolatile fractions of cold-pressed peel oils of Key and Persian lime as well as grapefruit were separated by high-speed countercurrent chromatography (HS-CCC). In addition to the isolation of the main coumarins, psoralens and polymethoxyflavones, a number of minor constituents were enriched and successfully characterized by GC-MS and HPLC-UV. 5,7,8-Trimethoxycoumarin and the cyclical acetals of oxypeucedanin hydrate with citral were determined as new nonvolatile trace constituents of lime oils and confirmed by NMR spectroscopy. The citral oxypeucedaninyl acetals were found particularly in Key lime oil type A, which as a result of the juice-oil contact, is exposed to acidic conditions during industrial processing. Some of the confirmed minor constituents, such as pabulenol, isooxypeucedanin, and oxypeucedanin methanolate in lime as well as auraptenol in grapefruit, may have been generated by hydrolysis-sensitive precursors during CCC separation or their respective industrial processing techniques.  相似文献   
85.
The understanding of the normal position of the third phalanx (P3) and the distal sesamoid bone in relation to the size and shape of the hoof capsule in sound horses is helpful in the diagnosis of equine foot lameness. Some measurements on radiographs used to define the position of the pedal bone within the hoof capsule are significantly influenced by hoof trimming and the height of the withers. In this study, the front hooves of 40 Warmblood horses were radiographed twice, eight weeks apart, both before and after their hooves were trimmed by an experienced farrier. Using the software programme Metron PX, 22 parameters on the lateromedial view and 16 parameters on the dorsopalmar view were measured and the effect of hoof trimming and height of the withers were calculated, respectively. Some of the hoof parameters showed mild positive correlation with the height of the withers. In 70% of the horses the left hoof capsule and P3 were significantly larger than the right. Hoof trimming had a remarkable influence on hoof conformation, especially for parameters in the toe region. Of all the measurements that describe the position of the third phalanx (P3) in relation to the hoof capsule, the distances between the distal tip of P3 to the solar surface of the foot, P3 to the tip of the toe and P3 to the point of break-over showed the greatest differences before and after trimming. The database of the present study can be used by farriers and veterinarians as a guideline for routine and corrective shoeing of Warmblood horses.  相似文献   
86.
OBJECTIVE: To compare the doses of propofol required for insertion of the laryngeal mask airway (LMA) with those for endotracheal intubation in sedated dogs. STUDY DESIGN: Randomized prospective clinical study. Animals Sixty healthy dogs aged 0.33-8.5 (3.0 +/- 2.3, mean +/- SD) years, weighing 2.2-59.0 (23.4 +/- 13.6, mean +/- SD) kg, presented for elective surgery requiring inhalation anaesthesia. METHODS: Animals were randomly assigned to receive either a LMA or an endotracheal tube. Pre-anaesthetic medication was intravenous (IV) glycopyrrolate (0.01 mg kg(-1)) medetomidine (10 microg kg(-1)) and butorphanol (0.2 mg kg(-1)). Repeated IV propofol injections (1 mg kg(-1) in 30 seconds) were given until LMA insertion or endotracheal intubation was achieved, when the presence or absence of laryngospasm, the respiratory rate (fr) and the total dose of propofol used were recorded. RESULTS: The total propofol dose (mean +/- SD) required for LMA insertion (0.53 +/- 0.51 mg kg(-1)) was significantly lower than for endotracheal intubation (1.43 +/- 0.57 mg kg(-1)). The LMA could be inserted without propofol in 47% of dogs; the remainder needed a single 1 mg kg(-1) bolus (n = 30). Endotracheal intubation was possible without propofol in 3.3% of the dogs, 47% needed one bolus and 50% required two injections (n = 30). The f(r) (mean +/- SD) was 18 +/- 6 and 15 +/- 7 minute(-1) after LMA insertion and intubation, respectively. CONCLUSION AND CLINICAL RELEVANCE: Laryngeal mask airway insertion requires less propofol than endotracheal intubation in sedated dogs therefore propofol-induced cardiorespiratory depression is likely to be less severe. The LMA is well tolerated and offers a less invasive means of securing the upper airway.  相似文献   
87.
ObjectiveTo compare tidal volume estimations obtained from Respiratory Ultrasonic Plethysmography (RUP) with simultaneous spirometric measurements in anaesthetized, mechanically ventilated horses.Study designProspective randomized experimental study.AnimalsFive experimental horses.MethodsFive horses were anaesthetized twice (1 week apart) in random order in lateral and in dorsal recumbency. Nine ventilation modes (treatments) were scheduled in random order (each lasting 4 minutes) applying combinations of different tidal volumes (8, 10, 12 mL kg?1) and positive end-expiratory pressures (PEEP) (0, 10, 20 cm H2O). Baseline ventilation mode (tidal volume = 15 mL kg?1, PEEP = 0 cm H2O) was applied for 4 minutes between all treatments. Spirometry and RUP data were downloaded to personal computers. Linear regression analyses (RUP versus spirometric tidal volume) were performed using different subsets of data. Additonally RUP was calibrated against spirometry using a regression equation for all RUP signal values (thoracic, abdominal and combined) with all data collectively and also by an individually determined best regression equation (highest R2) for each experiment (horse versus recumbency) separately. Agreement between methods was assessed with Bland-Altman analyses.ResultsThe highest correlation of RUP and spirometric tidal volume (R2 = 0.81) was found with the combined RUP signal in horses in lateral recumbency and ventilated without PEEP. The bias ± 2 SD was 0 ± 2.66 L when RUP was calibrated for collective data, but decreased to 0 ± 0.87 L when RUP was calibrated with individual data.Conclusions and clinical relevanceA possible use of RUP for tidal volume measurement during IPPV needs individual calibration to obtain limits of agreement within ± 20%.  相似文献   
88.
Coarctation of the aorta has been described previously as either a post-mortem or angiographic finding in three dogs with clinical signs related to the aortic coarctation. A 10-year-old dog was presented for evaluation of suspected laryngeal paralysis. On physical examination, femoral pulses were absent bilaterally, with an indirect systolic blood pressure difference of 60 mmHg between the ipsilateral thoracic and pelvic limbs. Coarctation of the aorta was detected on a thoracic computed tomographic angiography study. The coarctation was pre-ductal in position, with extensive dilation of the descending thoracic aorta. Characteristic rib changes that are seen in humans with coarctation were not apparent in this dog. 3D reconstructions of the thorax provided high vascular definition with exact localization of the aortic narrowing.  相似文献   
89.
A female boa (Boa constrictor) from a zoological collection was submitted for necropsy after sudden death. Prominent pathological findings included a diphtheroid colitis, endoparasitism, focal pneumonia and inclusion bodies typical for inclusion body disease (IBD). In the colon entamoebae were identified, which differed in size and distribution from Entamoeba invadens. Gene sequence analysis of the 18S ribosomal RNA revealed 100% similarity with an Entamoeba species from the African bullfrog (Pyxicephalus adspersus), probably Entamoeba ranarum. The snake was possibly immunosuppressed, and the source of infection remains unclear. This is the first report of an infection with an amphibian Entamoeba species associated with colitis in a snake.  相似文献   
90.
Objective— To (1) evaluate and compare computer-assisted surgery (CAS) with conventional screw insertion (conventional osteosynthesis [COS]) for treatment of equine abaxial distal phalanx fractures; (2) compare planned screw position with actual postoperative position; and (3) determine preferred screw insertion direction.
Study design— Experimental study.
Sample population— Cadaveric equine limbs (n=32).
Methods— In 8 specimens each, a 4.5 mm cortex bone screw was inserted in lag fashion in dorsopalmar (plantar) direction using CAS or COS. In 2 other groups of 8, the screws were inserted in opposite direction. Precision of CAS was determined by comparison of planned and actual screw position. Preferred screw direction was also assessed for CAS and COS.
Results— In 4 of 6 direct comparisons, screw positioning was significantly better with CAS. Results of precision analysis for screw position were similar to studies published in human medicine. None of evaluated criteria identified a preferred direction for screw insertion.
Conclusion— For abaxial fractures of the distal phalanx, superior precision in screw position is achieved with CAS technique compared with COS technique.
Clinical Relevance— Abaxial fractures of the distal phalanx lend themselves to computer-assisted implantation of 1 screw in a dorsopalmar (plantar) direction. Because of the complex anatomic relationships, and our results, we discourage use of COS technique for repair of this fracture type.  相似文献   
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