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61.
62.
Bilateral hypoplasia of the soft palate and aspiration pneumonia occurred in a Standardbred foal. The filly was presented with a history of illthrift, dyspnoea, coughing and bilateral nasal discharge. Abnormal sounds (crackels and wheezes) were auscultated over all lung fields and the cervical trachea. Endoscopy revealed a shortened soft palate with a uvula-like mass protruding from the free border into the nasopharynx. Mucopurulent material was present in the trachea. Samples obtained by tracheal wash were submitted for cytology, culture and sensitivity testing. Results indicated a septic inflammatory process. On lateral radiographs of the thorax there were patchy areas of consolidation and air bronchograms. The foal was euthanased. Necropsy confirmed the presence of a palatal defect and aspiration pneumonia of moderate severity. No other congenital abnormalities were present. 相似文献
63.
G K Haibel P D Constable J L Rojko 《Journal of the American Veterinary Medical Association》1990,196(4):627-629
A mature nulliparous Saanen-type goat examined for episodes of vulvar hemorrhage had coalescing nodular vaginal masses. The histopathologic diagnosis from a biopsy specimen was leiomyofibromatosis. Because of the relationship of these tumors in bitches to cystic ovaries and the nonrecurrence in bitches after excision and ovariectomy, abdominal exploration was performed. Bilaterally cystic ovaries were removed, and the vaginal tumors slowly regressed over the subsequent year, although transvaginal adhesions formed because of the extensive superficial necrosis originally present. 相似文献
64.
Histological examination was performed on the cervical spinal cord from 13 horses with chronic cervical compressive myelopathy of 4 to 29 months duration. Structural alterations were correlated with clinical features. At the level of compression, the spinal cord was grossly deformed. Histological alterations included nerve fibre swelling and degeneration, occasional spheroids, astrocytic gliosis, increased macrophage activity and increased perivascular collagen. Myelin degeneration or loss at the level of the compressive lesion was greatest in the ventral and lateral funiculi and less consistently present in the dorsal funiculi. Asymmetry of lesions in the dorsal funiculi was associated with asymmetry of clinical signs in 5 horses. Histological alterations in areas of Wallerian degeneration were similar to that at the level of spinal cord compression, except that perivascular collagen was not increased. Wallerian degeneration was present cranial to the compressed site in the superficial portions of the lateral funiculi and in the middle of the dorsal funiculi. Caudal to the compressed site it was present in the ventral funiculi adjacent to the ventral median fissure and in the middle of the lateral funiculi. Deformation of the spinal cord did not correlate with the severity or duration of clinical signs but was positively correlated with the amount of perivascular collagen increase. The amount of nerve fibre swelling was not correlated with the severity of clinical signs but was negatively correlated with their duration. A rapid loss of nerve fibres apparently occurred early in the course of compression, since there was a marked decrease in the amount of nerve fibre swelling and Marchi stained degenerating myelin with increasing clinical duration.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
65.
The changes in abdominal dimensions and contour during late gestation and early lactation were investigated in 44 Holstein-Friesian cattle, 20 normal heifers and 17 normal cows, and seven cows that had a left displaced abomasum (LDA) surgically corrected by a right flank omentopexy in a previous lactation. Abdominal measurements were made eight times during the six months spanning the last trimester of pregnancy and the first three months of lactation, they included the circumference of the thorax and abdomen, the depth and width of the abdomen, the vertical distance between the ventral abdomen and the descending duodenum, the height at the withers, and the length of the trunk. There were significant changes in these dimensions during the last trimester of pregnancy, immediately after parturition and during the first three months of lactation. The depth of the abdomen and the vertical distance between the ventral abdomen and the descending duodenum were greater in the cows with a previous history of LDA than in those without. 相似文献
66.
Quantitative Physicochemical Analysis of Acid‐Base Balance and Clinical Utility of Anion Gap and Strong Ion Gap in 806 Neonatal Calves with Diarrhea 下载免费PDF全文
F.M. Trefz P.D. Constable I. Lorenz 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(2):678-687
Background
Acid‐base abnormalities in neonatal diarrheic calves can be assessed by using the Henderson‐Hasselbalch equation or the simplified strong ion approach which use the anion gap (AG) or the strong ion gap (SIG) to quantify the concentration of unmeasured strong anions such as d‐lactate.Hypothesis/Objectives
To determine and compare the clinical utility of AG and SIG in quantifying the unmeasured strong anion charge in neonatal diarrheic calves, and to examine the associations between biochemical findings and acid‐base variables by using the simplified strong ion approach. We hypothesized that the SIG provides a more accurate prediction of unmeasured strong anions than the AG.Animals
Eight hundred and six neonatal diarrheic calves admitted to a veterinary teaching hospital.Methods
Retrospective study utilizing clinicopathologic findings extracted from medical records.Results
Hyperphosphatemia was an important predictor of venous blood pH. Serum inorganic phosphorus and plasma d‐lactate concentrations accounted for 58% of the variation in venous blood pH and 77% of the variation in AG and SIG. Plasma d‐ and total lactate concentrations were slightly better correlated with SIG (r s = −0.69; −0.78) than to AG (r s = 0.63; 0.74).Conclusions and Clinical Importance
Strong ion gap is slightly better at quantifying the unmeasured strong anion concentration in neonatal diarrheic calves than AG. Phosphorus concentrations should be included as part of the calculation of A tot when applying the simplified strong ion approach to acid‐base balance to critically ill animals with hyperphosphatemia. 相似文献67.
The Centre for International Irrigation Training and Research has been established to provide a focus in Australia for training
and research in irrigation engineering management, and to develop management training programmes, in the first instance for
responsible managers of regional irrigation supply and distribution networks. The core programme is a six month course in
irrigation engineering management that has been developed with a careful balance of academic coursework and “on-the-job” training,
strongly oriented towards practical management.
The syllabus material has been drawn largely from the Australian experience, which provides a basis for mutual exchange and
interaction between the course participants. The academic content will follow three general themes which are Institutional
Frameworks (20%), Physical and Environmental Framework (40%) and System Operation, Management and Maintenance (40%). Field
training will be undertaken in regional irrigation centres in four states of Australia. 相似文献
68.
Estimating the mass of asteroid 253 mathilde from tracking data during the NEAR flyby 总被引:1,自引:0,他引:1
DK Yeomans J Barriot DW Dunham RW Farquhar JD Giorgini CE Helfrich AS Konopliv JV McAdams JK Miller WM Owen DJ Scheeres SP Synnott BG Williams 《Science (New York, N.Y.)》1997,278(5346):2106-2109
The terminal navigation of the Near Earth Asteroid Rendezvous (NEAR) spacecraft during its close flyby of asteroid 253 Mathilde involved coordinated efforts to determine the heliocentric orbits of the spacecraft and Mathilde and then to determine the relative trajectory of the spacecraft with respect to Mathilde. The gravitational perturbation of Mathilde on the passing spacecraft was apparent in the spacecraft tracking data. As a result of the accurate targeting achieved, these data could be used to determine Mathilde's mass as 1.033 (+/- 0.044) x 10(20) grams. Coupled with a volume estimate provided by the NEAR imaging team, this mass suggests a low bulk density for Mathilde of 1.3 grams per cubic centimeter. 相似文献
69.
P Hedenqvist DVM HE Orr† BVMS Cert LAS JV Roughan† BSc PhD LM Antunes† MSc DVM & PA Flecknell† M.A Vet MB PhD DLAS Dip ECVA MRCVS 《Veterinary anaesthesia and analgesia》2002,29(1):14-19
Objective To compare the characteristics of anaesthesia induced with ketamine/medetomidine administered by the subcutaneous and intramuscular routes and to assess the effects of the addition of butorphanol to this combination. Study design Prospective randomised study. Animals Six female New Zealand White rabbits. Methods Rabbits were given one of four combinations of ketamine and medetomidine (K/M) either subcutaneously (SC) or intramuscularly (IM) on four successive occasions with a 7‐day interval between treatments. The dose combinations were; 15/0.25 mg kg?1 SC; 15/0.25 mg kg?1 IM; 15/0.5 mg kg?1 SC, and 15/0.25 mg kg?1 together with 0.4 mg kg?1 butorphanol (K/M/B) SC. The effects of anaesthesia on arterial blood gas values and cardiovascular variables were recorded at predetermined time points. Toe and ear pinch reflexes were judged to determine the duration of surgical anaesthesia. Loss of the righting reflex was used to measure the duration of sleep time. Analyses used repeated measures analysis of variance. Results All groups lost the righting reflex and ear pinch response. Three animals in the groups that received K/M alone lost their toe pinch reflex, whereas four lost this reflex when given K/M/B. Time of onset of loss of the righting, toe and ear pinch reflexes did not differ significantly among the groups. The higher dose combination of medetomidine with ketamine and the combination of K/M/B produced a greater duration of loss of the ear pinch response than the lower dose of K/M administered by either route. No significant differences were found among the groups in the duration of loss of the toe pinch reflex. All animals developed a moderate bradycardia (mean heart rate <166 beats minute?1) and moderate hypoxaemia (mean PaO2 < 6.0 kPa). Animals given butorphanol showed the greatest reduction in respiratory rate (31 ± 13 breaths minute?1, p < 0.05) but this was not reflected in any significant differences in arterial PCO2, PO2 or pH among the groups. Conclusions Administration of K/M by the SC route produced equivalent effects in comparison to intramuscular administration. The addition of butorphanol increased the duration of anaesthesia, but produced a slight increase in the degree of respiratory depression. All dose rates resulted in hypoxaemia so oxygen should be administered when these combinations are used in rabbits. Clinical relevance Subcutaneous administration is both technically simpler and may cause less discomfort to the animal than IM injection, and so is preferred. The combination of K/M with butorphanol has relatively minor effects on the depth and duration of anaesthesia, so offers little advantage to the use of K/M alone. 相似文献
70.
Characterization of the analytic performance of an electrochemical point‐of‐care meter for measuring β‐hydroxybutyrate concentration in blood and plasma from periparturient dairy cattle 下载免费PDF全文