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Shiga toxin producing-Escherichia coli (STEC) is an important emerging pathogen, and ruminants are recognized as their main natural reservoir. The aim of this work was to establish the frequency of STEC in non-domestic mammals of the Zoo and Botanical Garden of La Plata City, Argentina, and to pheno-genotypically characterize STEC isolates. By polymerase chain reaction (PCR), Shiga toxin (stx) gene sequences were detected in 50.8% of 65 fecal samples. Twenty-five STEC strains were isolated from 38.5% of the Zoo's animals. Ten species of order Cetartiodactyla and one species of order Rodentia were recognized as new STEC carriers. STEC strains belonged to 7 different serotypes including new serotypes O12:H25 and O13:H6. Serotype O146:H28, previously associated with human infections, represented 24% of STEC isolates. The most frequent Shiga toxin identified were type 1c and type 2c. Nineteen strains were positive for iha gene, 8 strains were positive for ehxA gene. Moreover, all strains were positive for lpfAO113 and negative for rfbO157, eae, saa, lpfAO157/OI-141, lpfAO157/OI-154, efa1, and toxB genes. Results obtained by XbaI-pulsed-field gel electrophoresis (XbaI-PFGE) confirmed the transmission of STEC strains among different animal species and suborders. In addition, we observed a potential association between STEC-harboring animal and factors such as belonging to order Cetartiodactyla, living in a pit, and belonging to a non-autochthonous species. This is the first work developed with zoological mammals and STEC in Argentina.  相似文献   
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An 18-month-old cross-breed dog developed multiple skin nodules, which over 8 months had increased in size and number. Biopsy samples were submitted for histopathological examination and revealed multiple benign pilomatrixomas. The dog was treated with 1 mg kg(-1) isotretinoin daily, which led to a stabilization of the size and number of the lesions. Attempts to lower the dosage to an every other day regimen led to an increase in the nodules' size and number. Monthly complete blood count and chemistry tests and Schirmer tear tests were performed to monitor any adverse effects of the retinoid treatment. No adverse effects were noted. To the authors' knowledge, this is the first report of multiple pilomatrixomas arising in a young dog and successfully controlled with oral retinoids.  相似文献   
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Objective— To report long-term outcome after arthroscopic removal of fragmentation of the extensor process of the distal phalanx in horses.
Study Design— Case series.
Animals— Adult horses (n=13).
Methods— Medical records (2003–2004) of horses that had arthroscopic debridement of fragmentation of the extensor process of the distal phalanx were reviewed. Inclusion criteria included: lameness localized to the foot, fragmentation of the extensor process of the distal phalanx debrided arthroscopically, and a follow-up period of ≥4 years.
Results— Of the 13 horses, lameness was resolved in 11 (85%) initially but distal interphalangeal joint pain recurred in 2 (15%) within 1 year of surgery. Three (23%) other horses were retired because of lameness at other sites during the follow-up period resulting in 46% (6/13) being not lame and in full work after 4 years. Substantial changes were identified at surgery in the contralateral joint of 7 horses, even when fragments were only present unilaterally.
Conclusions— Arthroscopic debridement of fragmentation of the extensor process of the forelimb distal phalanx has a good short-term prognosis for resolution of lameness and return to work but a more guarded prognosis for long-term soundness.
Clinical Relevance— These results allow for more accurate prognostication preoperatively and may support early debridement of fragmentation of the extensor process of the distal phalanx.  相似文献   
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The objective of this study was to examine the effect of donor breed on pronuclear‐stage embryo yield to be used for DNA microinjection in a transgenesis goat program. Twelve Canindé and twelve Saanen goats were heat synchronized using a progestagen‐cloprostenol treatment. Forty‐eight hours before the sponge removal, superovulation was induced with a total administration of 4.4 mg/kg bodyweight NIH‐FSH‐P1, given twice daily in decreasing doses over 3 days. In addition, goats received 100 μg of GnRH and they were hand‐mated at 36 and 48 h after progestagen removal. Embryo recovery was performed by oviduct flushing at 72 h after sponge removal. Embryos were microinjected with a DNA construct and noticeable swelling of the nuclei was the criterion for successful microinjection. The total diameter, cytoplasm diameter, zona pellucida thickness and pronuclei diameter were measured for each microinjected embryo. A higher (p < 0.05) percentage of fertilized ova was observed in Canindé (89.9%) than Saanen (36.2%) goats. In addition, Canindé donors produced a higher percentage of pronuclear embryos when compared with Saanen: 72.5% vs 20.6% (p < 0.05), respectively. Successful microinjection was verified in 96.7% and 73.3% of times in Canindé and Saanen embryos, respectively (p < 0.05). Significant differences were observed for all morphometric parameters except for cytoplasm diameter. In conclusion, under our study experimental conditions, Canindé were more efficient than Saanen goats concerning the pronuclear embryo yield and manipulation. The use of Canindé goats in transgenesis programs could be increase the interest in their breeding and could be contribute to saving them from extinction.  相似文献   
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Total amino acid contents of several important U.S. potato cultivars grown in Maine, Idaho and The Red River Valley are listed along with nitrogen content. Differences in amino acid content among cultivars were roughly proportional to differences in total nitrogen. The effect of storage on amino acids in two cultivars was minor. The limiting essential amino acids compared to egg were MET and the sulphur amino acids.  相似文献   
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Resveratrol in the fruits of bilberry (Vaccinium myrtillus L.), the lowbush "wild" blueberry (Vaccinium angustifolium Aiton), the rabbiteye blueberry (Vaccinium ashei Reade), and the highbush blueberry (Vaccinium corymbosum L.) were measured using a new assay based on high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). The LC-MS/MS assay provided lower limits of detection than previous methods for resveratrol measurement, 90 fmol of trans-resveratrol injected on-column, and a linear standard curve spanning >3 orders of magnitude. The recoveries of resveratrol from blueberries spiked with 1.8, 3.6, or 36 ng/g were 91.5 +/- 4.5, 95.6 +/- 6.5, and 88.0 +/- 3.6%, respectively. trans-Resveratrol but not cis-resveratrol was detected in both blueberry and bilberry samples. The highest levels of trans-resvertatrol in these specimens were 140.0 +/- 29.9 pmol/g in highbush blueberries from Michigan and 71.0 +/- 15.0 pmol/g in bilberries from Poland. However, considerable regional variation was observed; highbush blueberries from British Columbia contained no detectable resveratrol. Because blueberries and bilberries are often consumed after cooking, the effect of baking on resveratrol content was investigated. After 18 min of heating at 190 degrees C, between 17 and 46% of the resveratrol had degraded in the various Vaccinium species. Therefore, the resveratrol content of baked or heat-processed blueberries or bilberries should be expected to be lower than in the raw fruit. Although blueberries and bilberries were found to contain resveratrol, the level of this chemoprotective compound in these fruits was <10% that reported for grapes. Furthermore, cooking or heat processing of these berries will contribute to the degradation of resveratrol.  相似文献   
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