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Serum hormones and metabolites of lean and obese gilts were determined. Fifteen Iberian and fifteen Landrace gilts, of approximately 20 kg body weight, were fed isoenergetic (13.6 kJ ME/g DM, semisynthetic diets either with equilibrated amino acid profile at two crude protein (CP) levels (12% (0.81% lysine (Lys)) and 16% CP (1.08% Lys) as-fed basis) or lysine deficient (12% (0.30% Lys) or 16% CP (0.36% Lys) as-fed basis for Iberian and Landrace, respectively). Lysine deficient diets were offered only at the optimal protein level for maximum protein accretion for each breed. Each dietary treatment was assayed in 5 animals. Gilts were allocated in metabolic cages at 21 ± 1.5 °C with free access to water and fed four times daily at 90% ad libitum during 10 days. On day 11th blood samples were taken 5–5.5 h postprandial and serum obtained and frozen at − 20 °C. Growth hormone (GH), insulin like growth factor I (IGF-1), insulin, leptin, glucose, urea, creatinine, cholesterol and triglycerides were determined. Landrace gilts had higher serum glucose (P < 0.05) and creatinine (P < 0.001) than Iberian while no differences (P = 0.122–0.494) were found for the rest of the biochemical variables. Higher serum levels of insulin, IGF-1 and leptin (60, P < 0.05; 79, P < 0.05 and 189%, P < 0.001, respectively) and no differences in GH (P = 0.512) were encountered in Iberian gilts compared to Landrace. Dietary crude protein did not alter the serum hormonal profile (P = 0.110–0.454). Serum cholesterol (total, P < 0.01; HDL, P < 0.05; LDL, P < 0.05) decreased and triglycerides and urea increased (P < 0.05 and P < 0.001, respectively) as dietary crude protein increased. When lysine deficient diets were used, serum glucose decreased (P < 0.05) and urea increased (P < 0.001) compared to equilibrated diets. Serum insulin (P = 0.052), IGF-1 (P < 0.05) and leptin (P = 0.051) concentration decreased when lysine deficient diets were fed to the animals while GH remained unaffected (P = 0.214).These data suggest that Iberian and Landrace growing gilts have distinct hormone and metabolite serum profiles which are altered by a severe dietary lysine deficiency.  相似文献   
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Norfloxacin (NF) ruminal distribution after intravenous (i.v.), intramuscular (i.m.) and oral (p.o.) administration was determined in order to assess the influence of the rumen on the pharmacokinetic behaviour of NF in sheep. Norfloxacin concentrations in rumen were detected after i.v. and i.m. administrations between 4 and 48 h in all animals studied. The experimental distribution ratios after i.v. and i.m. administration expressed as area under the concentration-time curve ratios AUC(rumen)/AUC(plasma) were 0.24 and 0.39, respectively, and thus lower than corresponding predicted value of 5.06. Apparently, drug persisted in the rumen content longer than in plasma. The experimental mean residence time ratios MRT(rumen)/MRT(plasma) after i.v. and i.m. administrations were 2.33 and 1.66, respectively. After p.o. administration, NF concentrations in the rumen content were extremely high compared with the respective plasma concentrations, resulting in mean peak concentrations ratio C(max-rumen)/C(max-plasma) of 383.66 and AUC(rumen)/AUC(plasma) experimental ratio of 402.32. This value was considerably higher (approximately 79 fold) than the predicted distribution ratio of 5.06. Our results suggest that the limited p.o. bioavailability of NF in ruminants could not be attributed to ruminal degradation.  相似文献   
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OBJECTIVE: To describe a novel stapling technique for creation of a complete cecal bypass, without ileal transection in horses. STUDY DESIGN: Experimental study. ANIMALS: Four adult horses. METHODS: Through a ventral median celiotomy, jejunocolostomy was made with an intraluminal anastomosis device (ILA-100) and oversewn with a Cushing pattern to reinforce the staple line. Immediately distal to the anastomosis, 4 rows of staples were applied using a thoracoabdominal stapling device (TA-90) to occlude the lumen of the distal jejunum and proximal ileum. Necropsy exams were performed at least 60 days after surgery. RESULTS: No intraoperative complications occurred. Cecal bypass was functional in all horses at necropsy. The most oral staple line across the ileum partially failed in 1 horse; however cecal bypass was functional. CONCLUSIONS: Complete cecal bypass without ileal transection is a viable alternative to traditional methods of complete cecal bypass. Two sets of staple lines across the ileum are recommended. Longer term follow-up is warranted before clinical use of this technique. CLINICAL RELEVANCE: Cecal bypass without ileal transection is technically simple and effectively bypasses the cecum. It also should intuitively require less time and have a reduced risk of contamination compared with complete cecal bypass with ileal transection.  相似文献   
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Fifty feline sarcomas associated with vaccine-site injection were evaluated to determine the immunohistochemical expression of p53 protein, basic fibroblast growth factor (FGF-b), and transforming growth factor-alpha (TGF-alpha). Forty-one tumors (82%) were fibrosarcomas (FS), eight (16%) were malignant fibrous histiocytomas (MFH), and one (2%) was a chondrosarcoma (CS). Overexpression of p53 protein was observed in the nuclei of tumor cells in 28 (56%) sarcomas; FGF-b expression was found in the cytoplasm of tumor cells in 40 (80%) feline sarcomas, but the staining was more intense in the spindle-shaped cells of FS than in polygonal or round cells of MFH. The single CS faintly expressed FGF-b. The majority of feline vaccine-associated sarcomas (43 of 50, 86%) expressed moderate or intense staining for TGF-alpha in the cytoplasm of tumor cells. Heterogeneous immunolabeling for p53, FGF-b, and TGF-alpha was present in neoplastic, multinucleated giant cells. Intense expression of FGF-b was statistically associated with younger cats (P < 0.01) and with tumors with nodular growth patterns (P = 0.02). In addition, sarcomas negative for p53 protein expressed FGF-b more frequently than did p53-positive tumors (P = 0.04). The frequency of FGF-b immunostaining was significantly higher in sarcomas with intense expression of TGF-alpha (P = 0.05). Immunohistochemical detection of p53 protein, FGF-b, and TGF-alpha suggests that these growth-regulating proteins may play different roles in the development of sarcomas associated with vaccine sites.  相似文献   
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Toxoplasma gondii is one of the most prevalent zoonotic protozoan parasites among warm‐blooded animal populations (humans included) around the world, causing multiple clinic manifestations including death in the most severe cases of infection. Due to the versatile life cycle of T. gondii and its diversity of potential hosts, there is a common perception that natural areas and wildlife are highly prevalent reservoirs for the parasite; however, information and reports of the parasite on wildlife populations in Colombia are scarce. Using PRC‐based detection analyses of the B1 gene, we evaluated the presence of T. gondii in 49 native small mammal species (10% of the mammal species of Colombia) from 4 different undisturbed natural habitats. Additionally, to understand the ecogeographical distribution of the parasite in Colombia, we developed a literature search of infection reports including information on the host species, density of records and occurrence patterns (using landcover and ecoregions) in natural, rural and urban areas. Our literature review showed a total of 8,103 reports of T. gondii for Colombia of which 86% were related to humans, and 14% to non‐human mammals and other categories, with just a single report associated to wildlife; additionally, 82% of all reports were associated to urban areas whereas only 18% to rural sites. Based on the negative results for the presence of T. gondii in our PCR‐based analyses and our literature search, we suggest that T. gondii has a synanthropic distribution in Colombia occurring in ecoregions as variable as the xeric scrubs in the northern lowlands and humid montane Andean forests, also we show a lack of information on the parasite relationship with wildlife, a concerning fact given that zoonoses are the leading mechanism for the emergence of infectious diseases.  相似文献   
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A morphological and morphometric comparison was made of a Babesia ovis strain isolated in Extremadura (Spain) and a B. ovis strain from Turkey. Strains were morphologically similar, with a clear predominance of single sub-spherical or anaplasmoid forms. The use of an image analyser to measure B. ovis merozoites revealed significant differences in the long axis, short axis and volume between the two strains. Both strains however behaved in a similar manner in the indirect fluorescent antibody (IFA) test, which suggests a high degree of common antigenicity, despite morphometric differences. Conversely, no cross-reaction was observed between these strains of B. ovis and the other antigens used: B. motasi (The Netherlands), B. motasi (Turkey), B. crassa (Iran) and Theileria ovis (Turkey). B. ovis is therefore considered to be the aetiological agent of babesiosis in the area under study.  相似文献   
139.
Fibronectin and its integrin receptor α5β1 were studied by immunohistochemical methods in five normal canine mammary glands, four dysplastic glands and 18 mammary tumours. The aim of the study was to evaluate the possible changes in the α5β1 integrin receptor and its ligand fibronectin in relation to the metastatic capacity of canine mammary neoplasms. The immunostaining of α5β1 was very uniform in the hyperplastic glands but uneven in the mammary tumours. The expression of α5 and β1 was diminished in metastatic tumours but there were some α5-positive cells with pronounced features of malignancy and immaturity. Stromal fibronectin was increased in most cases and cytoplasmic staining of fibronectin was observed in epithelial and myoepithelial cells in mammary neoplasms but not in normal or dysplastic mammary tissue. There was no relationship between the content of α5β1 and the expression of fibronectin in canine mammary tumours.  相似文献   
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