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41.
REASONS FOR PERFORMING STUDY: Feeding practices have been associated with colic in horses. If meal size and composition have an effect on gastric emptying, this could be one of the mechanisms by which feeding practices are related to the occurrence of colic. OBJECTIVES: To evaluate the effect of meal size and starch content on solid phase gastric emptying. METHODS: Solid phase gastric emptying of 3 different radiolabelled meals, small low-starch (SmLS), small high-starch (SmHS) and large high-starch (LgHS) meals, was measured in 5 horses by scintigraphy using 99mTc-disofenin. Data were compared among meals using nonlinear mixed-effects models and paired t tests. RESULTS: On a percentage basis, SmHS emptied significantly faster than LgHS and SmLS emptied significantly faster than SmHS meals. However, when meals of unequal size were compared by emptying rate in g/min and Kcal/min, LgHS emptied significantly faster than SmHS. CONCLUSIONS: Meal size and composition affect gastric emptying. POTENTIAL RELEVANCE: Further work needs to be performed in order to substantiate the possibility of a relationship between digestive functions and occurrence of colic and gastric ulcers.  相似文献   
42.
OBJECTIVE:To characterize eosinophil granule-derived proteins in cats. SAMPLE POPULATION: Eosinophils collected via peritoneal lavage from 2 cats. PROCEDURE: The cats were infested orally with Toxocara canis eggs and subsequently challenge-exposed with T. canis antigen injected IP to induce peritoneal eosinophilia; eosinophils were collected via peritoneal lavage. Eosinophil granule proteins were acid-extracted, separated by gel-filtration chromatography, and examined for their peroxidase, ribonuclease, and bactericidal activities; the N-terminal sequence of some of these proteins was determined and compared with homologue proteins from other species. RESULTS: 3 protein peaks were separated in the chromatogram. The first peak had both peroxidase and bactericidal activities. The second peak had ribonuclease and bactericidal activities, and the N-terminal sequence of the major protein was homologous with that of proteins of the ribonuclease A superfamily, including eosinophil ribonucleases from humans and other animal species. The third protein peak had bactericidal activity, and the N-terminal sequence of the major protein was homologous with that of human and murine major basic proteins. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that feline eosinophil granules contain major basic protein and eosinophil-associated ribonuclease and the granule proteins have peroxidase, ribonuclease, and bactericidal activities. In cats, characterization of eosinophil granule proteins may be useful in elucidation of the mechanism of tissue damage in eosinophil-associated diseases and development of new treatment options for those diseases. In addition, the identification of conserved structure and function of eosinophil granule proteins in cats is relevant from an evolutionary viewpoint.  相似文献   
43.
44.
Bovine herpesvirus 1 glycoprotein D (gD) gene expression by recombinant replication defective human adenovirus type 5 (HAdV-5) was investigated in calves using indirect immunofluorescence microscopy (IIFM), confocal laser scanning microscopy (CLSM) and RT-PCR. One fold intranasal instillation of HAdV-5-expressing gD in the cattle upper respiratory tract showed a short term expression of at least 5 days, but not 10 days, limited only to epithelial cells localised in the epithelium of the nasal mucosa in one out of six calves. Observed limited gene transfer into well differentiated cattle airway epithelial cells must be taken into consideration in order to enhance transfection efficiency, and consequently the vaccine potential of this vector.  相似文献   
45.
Escherichia coli is a common avian pathogen mainly associated with extraintestinal infections such as yolk sac infection (YSI). The aim of this study was to determine the serotypes and the presence of some virulence genes of E. coli strains isolated from different samples in a vertically integrated poultry operation in Mexico. Two hundred sixty-seven E. coli isolates from different samples were serotyped using rabbit serum against the 175 somatic (O) and 56 flagellar (H) antigens of the typing schema. Virulence genes were determined by colony blot hybridization, using DNA probes for st, eae, agg1, agg2, bfp, lt, cdt, slt, and ipaH diarrhea-associated virulence factors. The serogroup of 85% of the strains was determined; O19 (12%), 084 (9%), 08 (6%), and 078 (5%) were the most common. Using the complete antigenic formula (O and H), O19:NM (n = 31) was the serotype most frequently isolated from dead-in-shell embryos and in broilers that had died on the fourth, fifth, sixth, and seventh days after hatch. One hundred ten strains (41.2%) hybridized with one or more of the used probes. Of these, ipaH (72%), eae (30%), and cdt (27%) were the most common. Considering the origin of the respective isolates, 40% of the broiler farm strains were positive for at least one probe. Results show that some avian E. coli strains isolated in Mexico are included in avian pathogenic E. coli serotypes not previously reported, suggesting that they could be specific for this geographic area. The wide distribution of the ipaH gene among nonmotile strains suggests that this invasiveness trait could be important in YSI pathogenesis. On the other hand, some other genes could contribute to E. coli virulence during YSI.  相似文献   
46.
A two-month-old female Tibetan terrier was re-presented with an incomplete closure of the patent ductus arteriosus. Following a second attempt to close the shunt by coil embolisation, arterial embolisation occurred. The successful removal of the embolised coil is described.  相似文献   
47.
American Trypanosomiasis (AT) is an infectious parasitic disease produced by the protozoa Trypanosoma cruzi (T. cruzi). Infection is acquired by vectorial via but can also be transmitted congenitally, by ingestion of an infected host, by transfusion with contaminated blood or transplant of organs from an infected donor. Currently, AT is widely distributed from the South of the United States to South America. In Mexico, the presence of the parasite has been reported throughout the country where several reservoirs such as dogs, opossums, rats and cats have been identified. Yucatan is in the south-east of Mexico where AT is endemic and has been reported since 1940s. There is little information about the role of pigs as reservoirs of T. cruzi. The frequency of specific antibodies against T. cruzi was determined in fattening pigs from Yucatan, Mexico. After sampling in the 3 main areas of pig production in the state, IgG ELISA and Western blot were performed to identify seropositive cases. Association of farm size, farm area and production system with infected pigs was evaluated. From 273 sampled pigs, 5.4% (n = 15) positive cases were found. No association with evaluated factors and infected pigs was found. Pigs are also reservoirs of T. cruzi in the studied area. These findings are considered important to improve vectorial control in the area in order to avoid the parasite infection in animal populations destined for human consumption and avoid further transmission to humans.  相似文献   
48.
Feline haematology profiles of patients presented to the University of Bristol Small Animal Hospital from January 2000 to October 2005 were evaluated for thrombocytosis (defined as a platelets count of >700x10(9)/l and confirmed on smear evaluation). Thrombocytosis was found in 79 cats (4.64% of the hospital feline population), with values ranging from 703 to 1895x10(9)/l. Signalment, clinical presentation, concurrence of other haematological abnormalities, diagnoses and outcome were evaluated in 51 cases in which complete medical records were available. Other variables (feline immunodeficiency virus/feline leukaemia virus status, thyroxine level, haemoplasma PCR, toxoplasma antibody titres) were also evaluated. No association was found between the presence of thrombocytosis and breed or gender. Gastrointestinal signs were the most common clinical presentation. Lymphopenia was the most common concurrent haematological abnormality. Based on final diagnosis reached, cats were grouped both according to the DAMNITV classification and according to the body system affected. Amongst the DAMNITV classification, inflammatory/infectious conditions were most commonly associated with thrombocytosis. According to body systems, gastrointestinal involvement was most represented, followed by endocrine cases. No association was found between the severity of thrombocytosis and outcome.  相似文献   
49.
OBJECTIVE: To assess whether site-related changes in biochemical composition are present in the cartilage and subchondral and trabecular bone of the metacarpophalangeal joint of horses with early osteoarthritis. SAMPLE POPULATION: Right metacarpophalangeal joints from 59 mature warmblood horses. PROCEDURE: Biochemical data (cross-link, amino acid, DNA, and ash contents; denatured collagen and glycosaminoglycan [GAG] concentrations; bone mineral density; and mineral composition) were obtained from 2 differently loaded sites of phalanx I cartilage and subchondral and trabecular bone samples; data were compared with previously published values from nonosteoarthritic equine joints. RESULTS: Compared with findings in nonosteoarthritic joints, GAG concentration was lower in cartilage from osteoarthritic joints and there was a loss of site differences in cellularity and lysylpyridinoline (LP) cross-link content. In subchondral bone, LP cross-link content was decreased overall and there was a loss of site differences in osteoarthritic joints; ash content was higher in the osteoarthritic joints. Hydroxyproline content in trabecular bone from osteoarthritic joints was greater than that in nonosteoarthritic trabecular bone. In all 3 layers and at both sites, the linear increase of the pentosidine cross-link content with age had diminished or was not apparent in the horses with osteoarthritic joints. CONCLUSIONS AND CLINICAL RELEVANCE: In equine metacarpophalangeal joints with early osteoarthritis, distinct biochemical changes were detected in the cartilage and subchondral and trabecular bone. The dissimilarity in response of the different tissues and differences between the sites that are affected may be related to differences in biomechanical loading and transmission and dissipation of force.  相似文献   
50.
BACKGROUND: Retired racing Greyhounds are becoming common as pets. Because of their unique physiology, results of routine laboratory tests are frequently outside the reference interval for dogs. Compared with other breeds, Greyhounds have low serum protein concentrations, but the concentrations of different serum protein fractions have not been reported. OBJECTIVES: Our objectives were to evaluate the results of serum protein electrophoresis (SPE) in healthy, retired racing Greyhounds and compare them with a control group of age- and gender-matched non-Greyhound dogs. METHODS: Agarose gel electrophoresis was done using a standard method; the gels were stained with amido black and scanned with a Cliniscan 2 densitometer (Helena Laboratories, Beaumont, TX, USA). Protein fractions were identified by visual inspection of the electrophoretogram. A Student's t-test assuming equal variances was used to compare the concentration of the different fractions between groups. RESULTS: The concentrations of total protein, total globulins, and alpha-1-, alpha-2-, beta-1-, and beta-2-globulins were significantly lower and the albumin to globulin (A:G) ratio was significantly higher in Greyhounds than in non-Greyhound dogs (P < .05). There was no significant difference in albumin or gamma-globulin concentrations. CONCLUSIONS: Low serum protein concentrations in Greyhounds are the result of low concentrations of a- and b-globulins. These results should be kept in mind when evaluating both healthy and sick Greyhounds. Additional studies are needed to identify the individual proteins associated with low alpha- and beta-globulin concentrations in Greyhounds.  相似文献   
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