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51.
Sixty male and 60 female crossbred pigs were allocated to an experiment to investigate the effects of porcine somatotropin (pST) administration (0 or 6 mg/d) and dietary lysine content on growth performance, tissue deposition, and carcass characteristics over the live weight range of 80 to 120 kg. Pigs receiving pST were given diets containing 6.9, 7.8, 8.8, 9.7, 10.6, or 11.5 g lysine/kg, whereas control pigs received diets containing 4.8, 5.8, 6.9, 7.8, 8.8 or 9.7 g lysine/kg. These dietary levels ranged from 0.40 to 0.70 g available lysine/MJ of DE for pST-treated pigs and from 0.28 to 0.58 g available lysine/MJ of DE for control pigs. Pigs were individually housed in pens, and there were five replicates of each treatment. All diets contained 14.5 MJ of DE/kg and were offered for ad libitum consumption to pigs between 80 and 120 kg live weight. Growth rate increased exponentially and food conversion ratio (FCR) decreased exponentially with increasing levels of lysine. In addition, there was a significant sex x pST interaction such that pST reduced the sex difference in FCR. Growth rate was faster in boars than in gilts and was increased by pST at the higher levels of dietary lysine. Similarly, FCR was lower for boars than for gilts and was decreased by pST at the higher dietary lysine levels. The optimum growth rate and FCR were defined as the lysine level at which growth rate and FCR were 95% and 105%, respectively, of the lysine plateau. The optimum growth rate and FCR were achieved at similar dietary lysine contents and were approximately 0.35 and 0.52 g available lysine/MJ of DE for control and pST-treated pigs, respectively. Protein deposition in the carcass increased exponentially with increasing dietary lysine level, was higher in boars than in gilts, and was increased by pST at the higher dietary lysine contents. Sex had no effect on dietary lysine required to maximize protein deposition. The dietary lysine contents required to ensure 95% of plateau protein deposition of 104 and 153 g/d were 0.39 and 0.55 g available lysine/MJ of DE for control and pST-treated pigs, respectively. The increase in lysine requirement with pST seems to be commensurate with the increase in protein deposition.  相似文献   
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Gross and histopathologic examinations were performed on 70 North American bison (Bison bison) from a Mycobacterium avium paratuberculosis culture-positive herd. The bison examined were part of a breeding herd totaling 2,800 animals. Eight of 70 (11%) animals had gross findings of intestinal mucosal thickening, and 16 of 70 (23%) of the animals had enlarged mesenteric lymph nodes. Histologic lesions compatible with Johne's disease were diagnosed in 30 of 70 (43%) bison on the basis of the demonstration of noncaseating granulomatous inflammatory infiltrates and of one or more acid-fast bacilli characteristic of Mycobacterium avium paratuberculosis. A suspicious diagnosis of Johne's disease was obtained in 11 of 70 (16%) bison on the basis of the observation of noncaseating granulomatous inflammatory infiltrates without demonstrable acid-fast bacteria. Twenty-nine of 70 (41%) animals were assessed as histologically paratuberculosis free. Histologic results were compared to Johne's disease tests such as culture, serology, and polymerase chain reaction, which were performed on some of the cohort animals.  相似文献   
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This study reports data obtained from per-rectal 99mTc-pertechnetate portal scintigraphy in normal cats. It examines the effects of chemical restraint and the methods employed in defining regions of interest (ROIs) on the shunt index derived from this data. Six normal cats were used for the study; all six were chemically restrained for imaging using propofol and later four of them were manually restrained for comparison. Portal blood flow was studied and the mean shunt index was found to be 5.9%± 3.9 when ROIs were operator defined and 9.2%± 4.4 when ROIs were defined using an isocontour program. In cats that were restrained using propofol and operator defined ROIs, the mean value for the time between detection of radioactivity in the liver and in the heart was 14 ± 1 seconds.  相似文献   
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THE DURAL TAIL SIGN IN THE DIAGNOSIS OF MENINGIOMAS   总被引:3,自引:0,他引:3  
John P.  Graham  MVB  MSc  Susan M.  Newell  DVM  MS  Andra K.  Voges  DVM  Gregory D.  Roberts  DVM  MS  Jay M.  Harrison  MS 《Veterinary radiology & ultrasound》1998,39(4):297-302
In humans the dural tail is a sign seen on contrast enhanced T1 weighted magnetic resonance images. This finding is considered specific for meningioma. The purpose of this study was to determine how often the dural tail occurs in cats and dogs and whether it is a specific sign for meningiomas in these species. MR examinations for eighteen dogs and four cats with proven diagnoses were reviewed. Diagnoses included ten meningiomas (seven dogs and three cats), three gliomas, two pituitary tumors, single examples of two other tumor types and five patients with mass lesions due to inflammatory disease. Contrast enhanced T1 weighted images were evaluated independently by three of the authors for the presence of a dural tail, without knowledge of the diagnoses. The results were compared to the diagnosis for each patient and the performance of individual reviewers compared. When their results were averaged, the reviewers reported the presence of a dural tail in 6 of 10 (60%) meningiomas, although detection varied between observers from 40% to 80%. Each reviewer had one false positive result, two reported a dural tail with a chromophobe adenocarcinoma and one with a toxoplasma meningoencephalitis. When a dural tail is seen an associated mass is most likely a meningioma. It is uncertain whether the dural tail represents neoplastic infiltration beyond the margins of the meningioma. This should be considered when planning treatment.  相似文献   
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Excessive administration of phenylbutazone was associated with development of right dorsal ulcerative colitis. The clinical signs of right dorsal colitis include chronic colic and weight loss. The laboratory abnormalities include panhypoproteinemia and a high WBC count in the abdominal fluid. Medical management of the chronic colic and protein-losing enteropathy associated with the ulcerative lesions in the right dorsal colon and surgical bypass of the right dorsal colon did not result in long-term resolution of clinical signs. Resection of the ulcerated right dorsal colon through a right lateral approach at the 16th rib resulted in resolution of intestinal protein loss and colic. The results of this case suggest that surgical resection of the ulcerated right dorsal colon may be the recommended treatment for right dorsal ulcerative colitis.  相似文献   
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Moderate to severe ulcerative colitis of the right dorsal colon was diagnosed by necropsy or by exploratory celiotomy and biopsy in 13 horses with a primary clinical complaint of either colic, diarrhea, or weight loss. Clinical signs varied from acute fulminating diarrhea (possibly with fever), colic, dehydration, endotoxic shock and death, to a chronic condition manifested by mild intermittent colic up to several months in duration, and weight loss with or without mild diarrhea. In a large percentage of the horses, those affected had been hypovolemic and received nonsteroidal anti-inflammatory drugs (NSAID) or had received inappropriately high doses of phenylbutazone before the onset of illness. Experimental treatment of two horses with high doses of a phenylbutazone oral paste preparation (6 gm once daily for 5 days) and limitation of their water intake to approximately one half of maintenance requirement (for 5 days) resulted in reproduction of ulcerative colitis involving only the right dorsal colon, which was apparent at necropsy examination 11 and 15 days after initiation of drug use. It was concluded that localized ulcerative lesions in the right dorsal colon may be a previously unreported manifestation of toxicity due to the administration of NSAID.  相似文献   
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