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101.
Details were recorded of 47 cases of coxo-femoral dislocation observed in cattle over 1 year. Treatment was successful in 20/47 (42.6%) cases using a method of closed reduction. Factors that most strongly influenced the prognosis were identified. The most useful single prognostic factor was whether the cow was able to stand before reduction. Other factors that also had a strong positive influence on the prognosis were: age less than 3y, bodyweight less than 400kg and duration of dislocation less than 12h. Nineteen unsuccessful cases were examined at the knackery. Four were found to have a fracture of the proximal femur. The coxo-femoral joint was carefully dissected in the other 15 cases and there was no evidence of hip dysplasia. A seasonal incidence of dislocations, which coincides with the calving and mating periods, was demonstrated during the survey and from practice records for the previous 3 years.  相似文献   
102.
The success of embryo production in vitro depends upon the use of an efficient oocyte retrieval technique, and the best results have been obtained by laparoscopic aspiration. The aim of this study was to evaluate the effect of consecutive sessions of follicular aspiration on the quantity, quality and in vitro maturation competence of oocytes obtained from ewes subjected to hormonal stimulation. Six Santa Ines ewes underwent nine sessions of follicular aspiration by laparoscopy with a 7‐day interval between sessions, totalling 56 aspirations. After 24 h of culture, oocytes were stained and classified according to the stage of nuclear and cytoplasmic maturation. Oocyte retrieval rate was 61.4 ± 2%, resulting in a total of 249 oocytes. No significant variation was observed between sessions (p > 0.05). The average number of oocytes retrieved from each ewe was 6.4 ± 2 per session and 42 ± 4 in total. No significant difference was observed between the frequencies of the different stages of nuclear maturation: 32.72% mature, 40.74% immature and 26.54% degenerated/indeterminate oocytes; however, a significant difference was observed between the frequencies of the different stages of cytoplasmic maturation: 10.7% mature, 73.25% immature and 16.05% degenerated/indeterminate oocytes. No significant difference was observed in nuclear or cytoplasmic maturation between the weeks of procedure. We conclude that after nine consecutive sessions of follicular aspiration, the quantity and quality of retrieved oocytes remained unchanged as well as the levels of nuclear and cytoplasmic maturation obtained, demonstrating the viability of this technique for repetitive follicular aspirations on the same donor.  相似文献   
103.
An 8-year-old neutered Beagle dog was presented with polyuria and polydipsia. Routine clinicopathologic testing showed a significant lymphocytosis and proteinuria. Lymphocytes were of small to intermediate in size with a mature morphology. Infectious disease screening was negative. PCR for antigen receptor gene rearrangements showed a clonal T-cell receptor (TCR) rearrangement consistent with T-cell chronic lymphocytic leukemia (CLL). Bone marrow cytology showed <30% lymphocytes, while the proportion in splenic fine-needle aspirate cytology was considered increased. The dog was initially monitored but started on prednisolone and chlorambucil therapy 2 months later due to worsening clinical signs and progressive lymphocytosis. After an additional 2 weeks, the dog developed multifocal spinal pain and single-node lymphadenomegaly. Cytology of the lymph node showed a monomorphic population of large lymphoblasts consistent with lymphoma. Cytology of a cerebrospinal fluid sample also showed large lymphoblasts. PCR for antigen receptor gene rearrangement at both sites showed a clonal TCR rearrangement of the same molecular size as in the initial leukemic cells. The dog was diagnosed with a transformation of the CLL to Richter syndrome (RS) with involvement of the central nervous system (CNS). Therapy was started with L-asparaginase and an increased dose of prednisolone; however, the dog was euthanized due to progressive clinical signs. To our knowledge, this is the first report of canine RS with direct involvement of the CNS.  相似文献   
104.
105.
ABSTRACT One hundred sixty-four isolates of Xanthomonas campestris pv. campestris and other X. campestris pathovars known to infect cruciferous hosts (X. campestris pvs. aberrans, raphani, armoraciae, and incanae) were inoculated onto a differential series of Brassica spp. to determine both pathogenicity to brassicas and race. Of these, 144 isolates were identified as X. campestris pv. campestris and grouped into six races, with races 1 (62%) and 4 (32%) being predominant. Other races were rare. The remaining 20 isolates from brassicas and other cruciferous hosts were either nonpathogenic or very weakly pathogenic on the differential series and could not be race-typed. Five of these isolates, from the ornamental crucifers wallflower (Cheiranthus cheiri), stock (Matthiola incana) and candytuft (Iberis sp.), showed clear evidence of pathovar-like specificity to the hosts of origin. A gene-for-gene model based on the interaction of four avirulence genes in X. campestris pv. campestris races and four matching resistance genes in the differential hosts is proposed. Knowledge of the race structure and worldwide distribution of races is fundamental to the search for sources of resistance and for the establishment of successful resistance breeding programs.  相似文献   
106.
High-resolution nuclear magnetic resonance spectroscopy has been used to demonstrate the feasibility of determining iodine value and average molecular weight of oil in individual corn kernels. The procedure is rapid and nondestructive. Depending on heritability of individual fatty acids, this technique may greatly increase selection efficiency in breeding programs to alter the fatty acid composition of corn oil.  相似文献   
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108.
An 8‐year‐old Gypsy Vanner gelding presented to the University of Florida Ophthalmology service for the evaluation of chronic, recurrent corneal ulcers behind the third eyelid of the right eye. On ophthalmic examination, a cluster of aberrant hairs was identified growing along the margin of the third eyelid. This portion of third eyelid was surgically excised, and histopathology identified the haired tissue as a dermoid. Chronic keratitis secondary to a third eyelid dermoid was diagnosed, and excision appeared curative at 6 months post‐operative follow‐up.  相似文献   
109.
OBJECTIVE: To compare a recently developed recombinant MSP-5 competitive inhibition ELISA with a card agglutination test for detection of antibodies to Anaplasma marginale and Anaplasma centrale in Australian cattle. MATERIALS AND METHODS: The ELISA was compared with the card agglutination test using 208 sera from cattle in Anaplasma-free herds, 86 sera from cattle experimentally infected with A marginale or A centrale and 757 sera from cattle in areas endemic for A marginale. RESULTS: The specificity of the ELISA, based on testing 208 sera from cattle in Anaplasma-free areas, was 99.5%, and the sensitivities for detection of antibodies to A marginale and A centrale in sera from the experimentally infected cattle were 98.0% and 100%, respectively. For the same sets of sera, the specificity of the card agglutination test was 98.6% and the sensitivities for detection of antibodies to A marginale and A centrale were 98.0% and 100%, respectively. For the 757 sera collected from cattle in areas endemic for A marginale, the agreement between the ELISA and the card agglutination test depended on the positive threshold selected for the ELISA. The maximum achievable agreement was 91.5% (kappa = 0.73; 95% confidence interval 0.66, 0.79). CONCLUSION: We conclude that the competitive inhibition ELISA is a useful alternative to the card agglutination test for detection of A marginale or A centrale infection in cattle. The assay should be particularly useful for epidemiological applications such as prevalence studies and control programs.  相似文献   
110.
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