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51.
52.
Objective To review the breed, age, gender, clinical and laboratory findings, treatment and outcome of horses with caecal disease presented to a referral centre. Design Retrospective study of 96 cases. Procedure The breed, age, and gender of the study population were compared with the corresponding hospital population for the same period. The means (± SD) for clinical and laboratory findings were recorded for each caecal disorder. Treatment was categorised as medical or surgical, and outcome was recorded. Results Caecal diseases included impaction (40% of total cases), rupture associated with concurrent unrelated disease (13%), rupture with parturition (9%), rupture with no associated disease (5%), infarction (11%), torsion (9%), abscess or adhesion (7%), tumour (3%), and miscellaneous conditions (3%). The breed or gender of affected horses did not differ from the hospital population, although horses > 15 years were more frequently represented (P < 0.05). This age group was specifically more predisposed to caecal impaction (P < 0.05), as were Arabian, Morgan, and Appaloosa breeds (P < 0.05). In horses with caecal impaction transrectal examination was the most useful diagnostic procedure; 90% of affected horses treated medically were discharged while horses treated by typhlotomy alone, or typhlotomy and blind end ileocolostomy, had survival rates to discharge of 71% and 86%, respectively. Horses with caecal rupture associated with concurrent un-related disease showed no signs of impending rupture; all were receiving phenylbutazone, all were euthanased, and 50% had caecal ulceration at necropsy. Of horses with caecal rupture with parturition 56% had prior dystocia; in two-thirds the site of rupture was the ileocaecal junction and all were euthanased. Horses with caecal rupture with no associated disease died or were euthanased; rupture was idiopathic. Horses with caecal infarction usually had signs of abdominal pain and abdominal fluid changes consistent with peritonitis; transrectal examination was nonspecific, and typhlectomy was successful in seven of eight horses. Horses with caecal torsion had signs of severe, acute abdominal pain and typhlectomy was successful in three of five horses. Diagnosis of caecal adhesion or abscess was assisted by transrectal palpation in two of seven horses and surgical treatment was successful in two of five horses. A caecal tumour was diagnosed in three horses aged 20 years or older that presented with chronic weight loss. Other caecal diseases were uncommon. Conclusion Caecal disease is uncommon in equids but some specific features of the history and physical findings can alert the veterinarian to the possibility of caecal involvement in horses with gastrointestinal dysfunction. Medical or surgical therapy can be effective in horses where caecal rupture has not occurred.  相似文献   
53.

Objectives

To describe colostrum management practices carried out in northern Victorian dairy herds and to identify weaknesses in these areas that may affect calf health and welfare by comparing the results with the current industry recommendations

Methods

A questionnaire to obtain information about colostrum management and calf‐rearing practices was sent to commercial dairy farming clients of Rochester Veterinary Practice between June and September 2013. The questionnaire consisted of a general herd overview and colostrum harvesting practices.

Results

The response rate was 39% (58/150). Many dairy producers were not meeting the current industry recommendations in the following areas: (1) time of removal calf from the dam, (2) relying on calf suckling colostrum from the dam to achieve adequate passive transfer, (3) failing to supplement calves with colostrum, (4) feeding inadequate volumes of colostrum, (5) delayed colostrum harvesting, (6) pooling of colostrum, (7) failing to objectively assess colostrum quality or relying on visual assessment and (8) storing colostrum for a prolonged periods of time at ambient temperatures.

Conclusion

The results from this survey highlight the need for greater awareness of industry standards for colostrum management and feeding hygiene.
  相似文献   
54.
Objective Correlation of immunophenotype with history, anatomical and morphological features of lymphoid neoplasia in the koala.
Methods Routine necropsies were performed on 51 koalas with suspected lymphoid neoplasia between 1986 and 1997 in New South Wales and Queensland. Immuno-phenotyping was by an immunoperoxidase method utilising species cross-reactive antibodies raised against human lymphocytes and an antibody raised against koala IgG. Cases were classified according to organs and tissues affected and the morphological features of neoplastic cells.
Results Twenty-six (51%) of the cases were of the T cell immunophenotype, 12 (24%) were of B cell immunopheno-type and 13 (25%) did not stain. The age and sex of koalas did not correlate with immunophenotype (P = 0.686 and P = 1.000, respectively). Thirty-two cases were leukaemic and 36 had multiple organ involvement, probably reflecting presenta tion of koalas at advanced stages of disease. Abdominal tissue involvement was most common (44 cases), followed by nodal (32), atypical (21) and cervicomediastinal (14). The T cell immunophenotype was over-represented among the leukaemic cases (P = 0.013). Generally, the T cell immunophenotype predominated except for many affected atypical tissues. Neoplastic cells were mostly of medium nuclear size with round to oval nuclei. No correlations were found for cell morphology, mitotic index and immunopheno-type.
Conclusion The prognostic value of an immunopheno-typic, anatomical and morphological basis for the classifica tion of lymphoid neoplasia in the koala currently is limited by the need to detect these neoplasms at an early age, the requirement for freshly fixed tissues and the restricted range of available cross-reacting antibodies.  相似文献   
55.
A mare was referred for further evaluation of a mass found in the left caudal abdomen during a routine postpartum reproductive palpation. The mare was clinically normal with no history of health problems. Ultrasonographic examination of the mass confirmed its presence, but the origin of the mass could not be accurately determined. Routine haematology and serum biochemistry results were within normal limits. The mare was initially treated conservatively with antibiotics, but the mass continued to increase in size, so it was surgically excised. The mass involved the left ovary. The mare showed transient abdominal pain after surgery, but developed no other complications and was in foal 7 months later. On histology, the mass was diagnosed as a dysgerminoma, a rare ovarian tumour of germ cell origin.  相似文献   
56.
杨凌区降雨对作物生长适应性的模糊分析   总被引:1,自引:0,他引:1  
依据模糊数学理论 ,采用模糊综合评判方法 ,从降雨“适量”、“适时”和“有效程度”3个指标出发 ,就杨凌区降水资源对农作物生长发育适应性做了评价分析 ,并提出降雨对作物生长的适宜度模型。通过实地调查与计算分析 ,该模型较好地反映了杨凌区主要作物对该区降雨特征的适宜能力 ,同时也较好地反映了本区降雨资源的地域特征 ,为该地区农作物合理布局决策提供了科学依据  相似文献   
57.
Alpha-amylase inhibitor (alpha-AI) activity of Garcinia mangostana, commonly known as mangosteen, pericarp extracts was studied by assay guided fractionations from lipophilic to hydrophilic using combined solvent extraction and Amberlite XAD2 adsorption chromatography. Neither the lipophilic, xanthone containing fraction, nor the highly polar fraction, which has no affinity on Amberlite XAD2, showed any alpha-AI. The fraction that shows very high inhibitory activity contains primarily polyphenols and can be adsorbed on Amberlite XAD2. The IC50 of 5.4 microg/mL of this fraction is comparable to that of acarbose, a prescribed alpha-AI used in the control of type II diabetes, at 5.2 microg/mL. Total phenolic content (TPC) of each fraction was measured and the TPC has no correlation with the alpha-AI activity. The lipophilic fraction contains mainly xanthones as revealed by HPLC-MS analysis. Colorimetric analysis coupled with UV-vis and IR spectroscopic analysis demonstrated that the fractions with high alpha-AI activity are primarily oligomeric proanthocyanidins (OPCs) with little gallate moiety. There is also evidence to show that the alpha-AI by these OPCs is not purely by nonspecific protein complexation. Both tannic acid and G. mangostana OPCs precipitate BSA equally well but G. mangostana OPCs are 56 times more effective in inhibiting alpha-amylase.  相似文献   
58.
CASE HISTORY: A 14-year-old neutered male Bearded Collie was presented with a history of recurrent, intermittent urinary incontinence of 7 years duration.

CLINICAL FINDINGS: A large, firm, non-painful mass was found in the mid-abdominal region on palpation. Ultrasonography of the mass revealed a compartmentalised structure with mixed echogenicity, and which did not appear to be associated with any of the abdominal organs. Ultrasound-guided fine needle aspirates contained several clusters of epithelial cells with cytological features of hepatocytes. At exploratory laparotomy, the mass was found in the gastrosplenic ligament within the greater omentum.

PATHOLOGICAL FINDINGS AND DIAGNOSIS: Histopathologically, the mass consisted of sheets of hepatocytes, but without the characteristic hepatic architecture. The cells showed moderate variation in nuclear size and were sometimes binucle- ate. A diagnosis of hepatocellular carcinoma (HCC) in the mesentery was made.

CLINICAL RELEVANCE: The presence of ectopic hepatic tissue has been reported rarely in man and cats, but not in the dog. Neoplastic transformation of ectopic hepatic tissue is seen in man. This is the first report of the presentation, clinical findings and treatment of a dog with ectopic HCC.  相似文献   
59.
Objective To determine prevalences of feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV) infections in ‘healthy’ cats that, through acute misadventure or other circumstance, were presented to veterinary practitioners. Prevalences of FeLV and FIV in this population were compared to those in a population of predominantly sick cats. Design and procedures Serum specimens were obtained over a 2-year period from 200 cats oldeer than 1 year of age presented to veterinary clinics for routine procedures, including cat fight injuries or abscesses, vehicular trauma, neutering, dental scaling, vaccination, grooming or boarding. An additional 894 sera were obtained over approximately the same period from specimens submitted by veterinarians to a private clinical pathology laboratory, mainly from sick cats suspected of having immune dysfunction, but including some sera from healthy cats being screened prior to FeLV vaccination. FIV antibody and FeLV antigen were detected in samples using commercial enzyme immunoassays. Results Amongst 200 ‘healthy’ cats, the prevalence of FeLV infection was 0 to 2%, and the prevalence of FIV was 6.5 to 7.5%, depending on the stringency of the criteria used to define positivity. FIV infection was significantly more prevalent in cats which resided in an inner city environment (P = 0.013). Of the 894 serum specimens submitted to the laboratory by practitioners, 11/761 (1.4%) were FeLV positive, while 148/711 (20.8%) were FIV positive. The prevalence of FIV was significantly higher in these predominantly ‘sick’ cats than in cats seen for routine veterinary procedures (P < 0.00001), while there was no difference in the prevalence of FeLV (P = 0.75) Conclusions The prevalence of FeLV and FIV in healthy cats may have been substantially overestimated in some previous Australian surveys. FeLV infection would appear to be a rare cause of disease in Australian cats. The higher prevalence of FIV positivity in sick as opposed to healthy cats infers that FIV infection contributes to the development of disease.  相似文献   
60.
Objective
To assess students' perceptions of subject-based problem-based learning in the fourth year of the veterinary science course at the University of Queensland.
Design
A questionnaire-based study.
Procedure
Subject-based problem-based learning was introduced into parts of two fourth year subjects in a 5-year veterinary science course. The problem-based learning exercise used modified clinical cases and was computer-assisted. Students worked in groups of two to four, and small group discussion sessions were tutorless. Lectures were replaced by large group discussion and feedback sessions, led by the teacher, with approximately 85 students.
Results
There was a significant increase in the percentage of students who strongly agreed that they had better understanding of the subject, and had learned to apply principles from this class in new situations. The only consistent criticism by students was directed at the extra time required compared to traditional lecture-based subjects.
Conclusion
Students' perceptions of the learning outcome were very favourable for problem-based learning when compared to the lecture-based subject.  相似文献   
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