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81.
Canine granulocytic anaplasmosis is a disease diagnosed in many areas of the United States, with the highest prevalence reported in dogs in the upper midwestern, northeastern, and western states. It is also found in several European countries. Anaplasmosis can manifest with a wide range of clinicopathologic findings. A 20 wk old puppy was presented with physical examination and laboratory findings atypical of the disease. In addition to other signs, abdominal effusion was detected. Diagnostic evaluation confirmed that the puppy was positive for anaplasmosis. No morulae were found in peripheral white blood cells, but morulae were apparent in the white cells of the abdominal effusion. Leukopenia was observed, characterized by neutropenia, as opposed to the lymphopenia and eosinopenia typically seen with the disease. Blast cells were also seen in the peripheral blood, and reactive lymphocytes were noted in the bone marrow. The patient responded well to doxycycline therapy. All hematologic and physical abnormalities resolved. 相似文献
82.
A possible infection with encephalomyocarditis virus was investigated on two Minnesota pig farms which experienced an increase in stillborn and mummified fetuses, high pre-weaning mortality and reduced farrowing rates. The monthly averages for the numbers of piglets born dead per litter on farms A and B reached 4-6 and 3-6, the pre-weaning mortalities 50 per cent and 31 per cent, and the farrowing rates 52 per cent and 63 per cent, respectively. Serological and histopathological examinations supported a diagnosis of infection with encephalomyocarditis virus, but attempts to isolate the virus failed. Specific antibody to the virus was detected in both fetal and neonatal sera collected from abnormal litters. The predominant histopathological finding was myocarditis consisting of focal or diffuse mononuclear cell infiltration. The detection of specific antibody, and the myocardial lesions in stillborn fetuses, suggested that the problems were associated with infection by encephalomyocarditis virus. 相似文献
83.
Abstract: The literature on environmental conflict has expanded greatly over the past 10 years, yet most of the cases and theory have been from a Western, Northern, and developed world context. This volume concentrates on cases of current conflict and its management from Asian and Pacific nations. This paper presents a brief literature review of the nature of environmental conflict and highlights some of the key authors who have featured. Their conclusions are summarised into four key suppositions; a) Environmental conflict is a result of scarcity and represents social struggles against uneven usage and allocation of resources; b) Environmental conflict reflects poor performance by governments in developing complex public policy; c) Environmental conflict involves the issues of power and rights; d) Environmental conflict is an inevitable consequence of development and can be constructive. 相似文献
84.
Presence of an emerging pathogen of amphibians in introduced bullfrogs Rana catesbeiana in Venezuela
Rhea Hanselmann Margarita Lampo Laurie Fajardo-Ramos A Marm Kilpatrick Peter Daszak 《Biological conservation》2004,120(1):115-119
Chytridiomycosis is an emerging fungal disease of amphibians responsible for mass mortalities and population declines globally. One hypothesis for its recent emergence is anthropogenic introduction of the causative agent Batrachochytrium dendrobatidis through trade in amphibians for pets, food and biocontrol. In this study, we examined histological samples from apparently healthy American bullfrogs Rana catesbeiana that have been introduced into the Venezuelan Andes. B. dendrobatidis was present in 96% (46/48) of the individuals examined. In contrast to cases of chytridiomycosis outbreaks, the majority (44/46) of frogs had few, small lesions consistent with little or no clinical disease and no unusual mortality was observed. These findings have implications for amphibian declines in Venezuela and elsewhere. First, the high prevalence of Batrachochytrium but lack of clinical signs or chytridiomycosis-related mortality suggests that R. catesbeiana may be a good reservoir for this parasite in Venezuela. Second, the presence of this emerging pathogen in an introduced amphibian species suggests that trade and introduction of amphibians should be monitored and controlled to halt the spread of this pathogen nationally and internationally. 相似文献
85.
The use of cryopreserved semen for artificial insemination in equine breeding programs is increasing because of such benefits as reduction of injuries inherent in natural breeding. In the present study, semen straws from 1 ejaculate from each of 3 stallions predetermined to be poor freezers were thawed after long-term storage in liquid nitrogen (−196°C) at 3 different thaw rates (37°C for 30 seconds, 60°C for 8 seconds, 75°C for 7 seconds). Sperm samples were tested in triplicate for each stallion for motility in caffeine to detect all potentially motile sperm and sperm viability and capacitation status. The fast thaw rate significantly increased the percent of progressively motile sperm compared with the slow (P = .0113) and moderate (P = .0157) thaw rates. The fast thaw rate also improved sperm viability, as measured by the dual stain SYBR-14 and PI (P < .05). Similar improvements were achieved with semen from 3 stallions with average postthaw semen quality. Finally, the chlortetracycline (CTC) stain found that the fast thaw rate reduced the number of sperm undergoing premature acrosome reactions (P = .0329). In summary, thawing frozen equine sperm at 75°C for 7 seconds apparently caused less membrane damage on thawing resulting in enhanced postthaw motility and viability and reduced premature capacitation. 相似文献
86.
The intrinsic torque of freshly spun wool yarns is affected by ageing of wool roving prior to spinning as well as the storage
time of the yarn after spinning. The effect of physical ageing of roving on yarn torque properties has not been observed before
and this study shows that the yarn intrinsic torque increases with ageing of the roving and decreases or relaxes with the
yarn storage time. The dependency of the intrinsic torque on the roving ageing time and the yarn storage time after spinning
show a simple double-logarithmic shift factor of 0.42 compared with the value of 1 found generally for amorphous polymeric
materials. The self-plying twist of the yarns used in this study shows a close link to the intrinsic torque and both are affected
by the history of the roving prior to spinning. Significant reductions in the self-plying twist were obtained when deaged
rovings were used in spinning. When self-plying twist is used as a predictor of fabric spirality the roving and yarn history
needs to be considered. This study shows that low intrinsic torque yarns can be produced by deageing of the roving prior to
spinning. 相似文献
87.
88.
Serologic evidence incriminating a recently isolated virus (ATCC VR-2332) as the cause of swine infertility and respiratory syndrome (SIRS). 总被引:8,自引:0,他引:8
89.
Laurie A. Mitten Kenneth W. Hinchcliff Richard Sams 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1995,9(5):353-356
Evaluation of a portable blood gas analyzer, (StatPal II, Unifet, Inc, La Jolla, CA) was performed using tonometered solutions and equine blood. Samples were analyzed by the StatPal II and either an Instrument Laboratory IL1306 (Lexington, MA) or a Radiometer ABL50 blood gas analyzer (Radiometer America Inc., Westlake, OH). Comparison of the StatPal II and the IL1306 was done by analysis of 3 tonometered solutions (acidic, normal, and alkalotic) and 27 equine venous blood samples. Blood pH, Pco2 , Po2 , and [HCO3 - ] values were altered by IV infusion of 5% sodium bicarbonate or exercising the horses on a treadmill. Comparison of the StatPal II and the Radiometer was performed by analysis of 78 blood samples collected from Standard-bred horses before a race. Data were analyzed for the venous blood samples using a paired two-tailed Student's t test and Bland-Altman plots, with significance set at P < .05. The coefficients of variation for pH, Pco2 , Po2 , and [HCO3 - ] values of the tonometered solutions analyzed by the StatPal II ranged from 0.067% to 0.087%, 2% to 3.21 %, 1.21 % to 2.67%, and 0.267% to 0.828%, respectively. Comparison of the equine blood samples analyzed by the StatPal II and the IL1306 demonstrated statistically significant, but clinically irrelevant differences in pH, Pco2 , and Po2 , but not [HCO3 - ]. There were statistically significant, but clinically irrelevant differences between the StatPal II and the Radiometer for pH, Pco2 , and [HCO3 - ], but not for Po2 -It is concluded that the StatPal II provides reproducible and acceptable analysis of equine venous blood gas samples. 相似文献
90.
Serum Fructosamine Concentration as an Index of Glycemia in Cats With Diabetes Mellitus and Stress Hyperglycemia 总被引:2,自引:0,他引:2
Kathy L. Crenshaw Mark E. Peterson DVM Laurie A. Heeb Scott D. Moroff Rhett Nichols 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1996,10(6):360-364
The purpose of this study was to evaluate fructosamine concentrations in clinically healthy cats, sick cats with stress hyperglycemia, and untreated diabetic cats to determine the usefulness of this test in diagnosing diabetes mellitus in cats, and in differentiating the disease from stress-induced hyperglycemia. In addition, we evaluated if the degree of glycemic control in cats treated for diabetes influenced their serum fructosamine concentrations. In the 14 sick cats with stress hyperglycemia, the median serum fructosamine concentration (269 μmol/L) was not significantly different from the median value in the 26 clinically normal cats (252 μmol/L). Two of the 14 cats with stress hyperglycemia (14.3%) had serum fructosamine concentrations above the upper limit of the reference range (175 to 400 μmol/U; on the basis of these results, the test specificity was calculated as 0.86. In 30 cats with untreated diabetes mellitus, the median serum fructosamine concentration was 624 μmol/L, markedly higher than the value in either the normal cats or the cats with stress hyperglycemia. All but 2 of the 30 untreated diabetic cats (6.7%) had serum fructosamine concentration above the upper limit of the reference range; on the basis of these results, the sensitivity of serum fructosamine concentration as a diagnostic test for diabetes mellitus was 0.93. When 30 diabetic cats receiving treatment were divided into 3 groups according to their response to treatment (ie, poor, fair, and good), the 16 cats that had a good response to treatment had significantly lower serum concentrations of both glucose and fructosamine compared with cats that had either a fair or poor response to treatment. A significant correlation (rs= .70, n = 100, P < .001) was found between serum concentrations of glucose and fructosamine. Results of this study indicate that quantification of serum fructosamine concentration is a meaningful test for the diagnosis of diabetes, for differentiating diabetes from stress hyperglycemia; and for monitoring the metabolic control in treated diabetic cats. 相似文献