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31.
An unusual occipitoatlantoaxial malformation is described in a 2-week-old male part Arabian foal that was unable to stand at birth and showed signs of spastic tetraparesis due to a cervical spinal cord compression. There were 2 atlases present. One was fused to the occipital bones. The other articulated with the first atlas and an axis which had a long dens that projected into the vertebral canal. Examination of the ossification centers of the axis indicated partial duplication of that bone. 相似文献
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W G Luce C V Maxwell D S Buchanan R O Bates M D Woltmann S A Norton G N Dietz 《Journal of animal science》1989,67(2):329-333
A study involving 546 crossbred gilts from six seasons was conducted to evaluate raw mung beans as a partial replacement for soybean meal in diets for gilts during gestation. Gilts were randomly allotted to either a control sorghum grain-soybean meal diet or a diet in which a portion of the soybean meal was replaced with mung beans. In the first three seasons, gilts were fed diets in which the protein supplement was totally soybean meal or 89% mung beans (high level) and 11% soybean meal. In the last three seasons the level of mung beans in the supplemental protein was reduced to 61% mung beans with 39% soybean meal (moderate level). Feeding the high level of mung beans decreased (P less than .05) weight gain during gestation and reduced (P less than .05) weight loss during lactation compared with gilts fed the control diet or the moderate level of mung beans. Little difference was noted in litter size at birth, but litter size at 21 d for gilts fed moderate levels of mung beans was less (P less than .05) than for gilts fed the control diet or the high level of mung beans. Little difference was noted in survival rate to 21 or 42 d or individual and litter weights at birth and 21 d. Pig and litter weights at 42 d, however were reduced in gilts fed the high level of mung beans (P less than .05 and P less than .10, respectively) compared with the control diet.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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The lumbosacral-canal system in birds most likely operates as a sense organ involved in the control of balanced walking and perching, but our knowledge of it is superficial. Penguins constitute interesting objects for the study of this system due to their upright walking, but only the Humboldt penguin, Spheniscus humboldti, and some incomplete fossil penguin synsacra have been studied in this respect. Here, we give an integrative comparative insight into the synsacral canal of extant Emperor penguin, Aptenodytes forsteri, Adelie penguin, Pygoscelis adeliae, and Eocene giant Anthropornis and/or Palaeeudyptes Antarctic penguins, using computed tomography imaging and associated data-extraction methodologies, complemented by analytical approaches ranging from geometric morphometrics to modularity, curvature, and wavelet analyses. We document that the variability in the number of synsacro-lumbar vertebrae is evolutionarily conserved, and all studied synsacra possess osteological correlates of the lumbosacral-canal system. We also found that Eocene and extant Antarctic penguins were separable on the basis of the main direction of the shape-related (size-independent) variability within said system, and A. forsteri was unique in the entire studied set in terms of the relative cranial shift of this compound structure. Moreover, we suggest that the evolutionary processes, shaping both the terrestrial posture and gait, were responsible, in extant penguins, for the increased simplicity and stability of the synsacral canal cross-sectional periodic patterns, as well as pave the way for the lumbosacral-canal system modularity characterized by reduced atomization/complexity. 相似文献
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Rune Dietz Ari D Shapiro Mehdi Bakhtiari Jack Orr Peter L Tyack Pierre Richard Ida Grønborg Eskesen Greg Marshall 《BMC ecology》2007,7(1):1-10
Background
Free-ranging narwhals (Monodon monoceros) were instrumented in Admiralty Inlet, Canada with both satellite tags to study migration and stock separation and short-term, high-resolution digital archival tags to explore diving and feeding behaviour. Three narwhals were equipped with an underwater camera pod (Crittercam), another individual was equipped with a digital archival tag (DTAG), and a fifth with both units during August 2003 and 2004.Results
Crittercam footage indicated that of the combined 286 minutes of recordings, 12% of the time was spent along the bottom. When the bottom was visible in the camera footage, the narwhals were oriented upside-down 80% of the time (range: 61100%). The DTAG data (14.6 hours of recordings) revealed that during time spent below the surface, the two tagged narwhals were supine an average of 13% (range: 9–18%) of the time. Roughly 70% of this time spent in a supine posture occurred during the descent.Conclusion
Possible reasons for this upside-down swimming behaviour are discussed. No preference for a clockwise or counter-clockwise direction of roll was observed, discounting the possibility that rolling movements contribute to the asymmetric left-handed helical turns of the tusk. 相似文献37.
Gödecke T Yao P Napolitano JG Nikolić D Dietz BM Bolton JL van Breemen RB Farnsworth NR Chen SN Lankin DC Pauli GF 《Fitoterapia》2012,83(1):18-32
Despite numerous in vitro/vivo and phytochemical studies, the active constituents of Angelica sinensis (AS) have not been conclusively identified for the standardization to bioactive markers. Phytochemical analyses of AS extracts and fractions that demonstrate activity in a panel of in vitro bioassays, have repeatedly pointed to ligustilide as being (associated with) the active principle(s). Due to the chemical instability of ligustilide and related issues in GC/LC analyses, new methods capable of quantifying ligustilide in mixtures that do not rely on an identical reference standard are in high demand. This study demonstrates how NMR can satisfy the requirement for simultaneous, multi-target quantification and qualitative identification. First, the AS activity was concentrated into a single fraction by RP-solid-phase extraction, as confirmed by an alkaline phosphatase, (anti-)estrogenicity and cytotoxicity assay. Next, a quantitative 1H NMR (qHNMR) method was established and validated using standard compounds and comparing processing methods. Subsequent 1D/2D NMR and qHNMR analysis led to the identification and quantification of ligustilide and other minor components in the active fraction, and to the development of quality criteria for authentic AS preparations. The absolute and relative quantities of ligustilide, six minor alkyl phthalides, and groups of phenylpropanoids, polyynes, and poly-unsaturated fatty acids were measured by a combination of qHNMR and 2D COSY. The qNMR approach enables multi-target quality control of the bioactive fraction, and enables the integrated biological and chemical standardization of AS botanicals. This methodology can potentially be transferred to other botanicals with active principles that act synergistically, or that contain closely related and/or constituents, which have not been conclusively identified as the active principles. 相似文献
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