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Objective  To compare the brightness of South American camelid venous blood to that of Equidae.
Study design  Prospective clinical evaluation.
Animals  Twelve South American camelids (eight llamas, four alpacas), eight horses and ponies (control group).
Methods  Appropriately sized catheters were placed in the jugular vein of each animal under local anaesthesia. The blood spilt before the catheter was capped was caught on a white tile. A sample of blood was drawn for blood-gas analysis. The brightness of the blood (both on the tile and in the syringe) was matched to a colour chart (1 = darkest red, 8 = brightest red) by a single observer under bright light conditions. Packed cell volume (PCV) and partial pressure of oxygen (PvO2) in the blood were also measured on the syringe blood. Normally distributed data were compared using a two tailed t -test, and non-normally distributed data were compared using a Mann–Whitney U -test. Significance was set at p  < 0.05.
Results  Camelid venous blood was significantly brighter red than that of horses and ponies both on the white tile ( p  = 0.0003) and in the syringe ( p  = 0.0001). PCV was significantly lower in camelids (32 ± 4%) compared with horses (37 ± 5%). Partial pressure of oxygen values were similar between groups.
Conclusions and clinical relevance  Jugular venous blood in alpacas and llamas is significantly brighter red than that of horses. Colour should not be used as a sole determinant of venous or arterial catheterization in this species.  相似文献   
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Research conducted by the Anthrozoology Institute and the Defence Science and Technology Laboratory has shown that many working dogs exhibit high levels of physiologic stress in response to kenneling (Hiby et al., 2006, Rooney et al., 2007a). Furthermore, these dogs tend to perform poorly during training, establishing links between welfare and working ability (Rooney et al., 2005, Rooney et al., 2007b). Subsequently, we have been studying how kenneling affects welfare and working ability. Specifically, we have investigated which elements within housing and husbandry influence welfare, which of these seem to be the most important, and how environmental enrichment (e.g. feeding devices) can affect welfare and working ability. This paper draws together results from all of these studies, identifying signs that may be indicative of compromised welfare, and providing guidelines, based on scientific evidence, for how to improve kenneled working dog welfare. It reproduces an unpublished guide designed to primarily inform and advise practitioners who are responsible for caring for, and/or handling working dogs. This paper aims to ensure that practitioners are updated of the most recent advances in working dog welfare, and hence many of the studies summarized here are yet to be published in full, in peer-reviewed journals.  相似文献   
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