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Objective To develop a simple and effective surgical technique for third‐compartment cannulation in alpacas. Design Prospective study using six adult male alpacas. Methods General anaesthesia was induced and a polyurethane gastrostomy tube was surgically implanted into the distal portion of the third compartment. Results Three of the alpacas retained their cannulas for a 100‐day period; however, three cannulas were dislodged during the study. Two of the three dislodged cannulas were replaced during a second surgical procedure. Cannulas were well tolerated by the alpacas and all animals remained clinically healthy during the study period. Third compartment contents did not leak from the cannulation site. The tubes were manually removed following the completion of the study and the small defect in the body wall quickly healed over in all animals. Conclusion Surgical placement of polyurethane tubes designed for percutaneous endoscopic gastrostomy is a useful method of cannulating the third compartment in camelids. This technique can be used for experimental studies and possibly could be used for nutritional support and fluid therapy in sick camelids that might need long‐term care.  相似文献   
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This study compared the sensitivity of acetate tape impression and skin squeezing with that of deep skin scraping for the diagnosis of demodicosis in dogs. Demodex canis was detected in 100% of acetate tape impressions obtained after skin squeezing and in 90% of deep skin scrapings. There was a significant difference (P < 0.001) between the techniques in the total number of mites detected. Acetate tape impression with skin squeezing was found to be more sensitive than deep skin scraping and is an alternative diagnostic method for canine demodicosis.  相似文献   
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Four spider species and the predacious mitePhytoseiulus persimilis (Athias-Henriot) were examined in the laboratory for their capacity to feed on the carmine spider mite,Tetranychus cinnabarinus (Boisduval). The adult females ofChiracanthium mildei L. Koch showed the highest capacity for feeding onT. cinnabarinus (27.5 mites/day) and differed significantly from all other spider species, including the immatureC. mildei which consumed an average of 18.9 mites/day — nearly equal to that of the Oxyopidae species (16.8 mites/day). The salticid (10.1 mites/day) and theridiid (9.5 mites/day) spider species had the lowest capacity, which was nearly equal to that of the predacious miteP. persimilis (11.3 mites/day). Results indicate that spiders play an important role as mite predators.  相似文献   
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A 19-yr-old spayed female coyote (Canis latrans) was evaluated for an elliptical swelling of the skin beneath its right eye and an elevated mass that involved the soft and hard palate and gingivae around the upper right carnassial tooth and molars. Histopathologic analysis revealed a squamous cell carcinoma, and a postmortem examination revealed no evidence of vascular invasion or dissemination to the regional lymph nodes or viscera. This report describes the biology and progresion of an oral squamous cell carcinoma in an aged captive coyote.  相似文献   
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Data from recent oceanographic cruises show that phytoplankton community structure in the Ross Sea is related to mixed layer depth. Diatoms dominate in highly stratified waters, whereas Phaeocystis antarctica assemblages dominate where waters are more deeply mixed. The drawdown of both carbon dioxide (CO2) and nitrate per mole of phosphate and the rate of new production by diatoms are much lower than that measured for P. antarctica. Consequently, the capacity of the biological community to draw down atmospheric CO2 and transport it to the deep ocean could diminish dramatically if predicted increases in upper ocean stratification due to climate warming should occur.  相似文献   
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In this study we have examined luteal function in non-lactating and late lactation dairy cows on day 5 of the cycle, during the period of the post-ovulatory progesterone rise. Comparison of luteal progesterone content and in vitro synthetic capacity with circulating plasma progesterone demonstrated that circulating progesterone concentration is a function of total luteal activity rather than the activity of individual units of tissue. Incubation of luteal tissue in vitro demonstrated stimulatory activity of LH and IGF-I, and to a greater degree IGF-II, on luteal progesterone synthesis. Finally the study showed no effect of double ovulation on luteal function. Occurrence of double ovulation in 35% of animals was not associated with any difference in luteal function or plasma progesterone concentrations.  相似文献   
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