Eastern equine encephalitis in a flock of emus (Dromaius novaehollandiae).     

T N Tully  S M Shane  R P Poston  J J England  C C Vice  D Y Cho  B Panigrahy 《Avian diseases》1992,36(3):808-812

Eastern equine encephalitis (EEE) was diagnosed in a flock of emus in southeastern Louisiana. The outbreak involved juvenile and adult breeders ranging in age from 20 to 36 months, with an attack rate of 76% and a case fatality rate of 87%. The diagnosis was confirmed by isolation and characterization of the viral agent, and by detection of EEE antibody in two recovered emus. High mortality was preceded by marked depression, hemorrhagic diarrhea, and emesis of blood-stained ingesta. On postmortem examination, hemorrhagic enteritis and multiple petechia of viscera were observed. Microscopic changes included severe necrosis of hepatocytes, intestinal mucosa, and necrotizing vasculitis of the spleen and lamina propria of the intestine. No nervous system lesions were observed. This outbreak occurred concurrently with EEE in horses and was attributed to unseasonably heavy rainfall with an abundance of arthropod vectors and proximity to free-living reservoir host species.  相似文献   

Chronic diarrhea associated with intestinal anomalies in a six-year-old dog.     

E Zenger  W N Evering  M D Willard 《Journal of the American Veterinary Medical Association》1992,201(11):1737-1740

A 6-year-old mixed-breed dog was referred because of chronic diarrhea, which had begun after antibiotic treatment for pulmonary disease. Intestinal bacterial overgrowth was presumptively diagnosed on the basis of intestinal mucosal cytologic examination and low serum cobalamin concentration. When the diarrhea did not respond to treatment, contrast radiography was performed and a short small intestine was found. The diarrhea could not be managed by medical treatment, and the dog was euthanatized. Necropsy revealed 2 blind intestinal pouches attached to a 46-cm length of small intestine connecting the stomach and colon. The dog's deteriorating condition was attributable to necrosis and rupture of 1 of the pouches.  相似文献   

Cardiopathological observation on a case of persistent ventricular tachycardia in a pony mare.     

N Machida  T Nakamura  K Kiryu  S Haramaki  K Too 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(6):1213-1216

A 20-year-old pony mare with persistent ventricular tachycardia (VT) was examined cardiopathologically. At necropsy, the heart was enlarged and rounded with both ventricular dilatation. In a longitudinal section of the ventricular septum, a large grayish white patchy lesion (5 x 25 mm) was detected in the relatively higher portion. Microscopically, the lesion was extensive myocardial fibrosis located in the vicinity of the proximal part of the left bundle branch. Partially the fibrotic lesion was in contact with the branch. Such a lesion might play an important role in creating a suitable background for the development of VT via automaticity or reentry mechanism.  相似文献   

Effects of predator-induced visual and olfactory cues on 0+ perch (Perca fluviatilis L.) foraging behaviour     

V. N. Mikheev  J. Wanzenböck  A. F. Pasternak 《Ecology of Freshwater Fish》2006,15(2):111-117

Abstract –  Foraging juvenile fish with relatively high food demands are usually vulnerable to various aquatic and avian predators. To compromise between foraging and antipredator activity, they need exact and reliable information about current predation risk. Among direct predator-induced cues, visual and olfactory signals are considered to be most important. Food intake rates and prey-size selectivity of laboratory-reared, naive young-of-the-year (YOY) perch, Perca fluviatilis , were studied in experiments with Daphnia magna of two size classes: 2.8 and 1.3 mm as prey and northern pike, Esox lucius , as predator. Neither total intake rate nor prey-size selectivity was modified by predator kairomones alone (water from an aquarium with a pike was pumped into the test aquaria) under daylight conditions. Visual presentation of pike reduced total food intake by perch. This effect was significantly more pronounced (synergistic) when visual and olfactory cues were presented simultaneously to foraging perch. Moreover, the combination of cues caused a significant shift in prey-size selection, expressed as a reduced proportion of large prey in the diet. Our observations demonstrate that predator-induced olfactory cues alone are less important modifiers of the feeding behaviour of naive YOY perch than visual cues under daylight conditions. However, pike odour acts as a modulatory stimulus enhancing the effects of visual cues, which trigger an innate response in perch.  相似文献   

Spermatophore cryopreservation and artificial insemination of black tiger shrimp, Penaeus monodon (Fabricius)     

Amrit N Bart  Sudarhma Choosuk  & Dhirendra P Thakur 《Aquaculture Research》2006,37(5):523-528

To develop an appropriate cryopreservation protocol for spermatophores of black tiger shrimp, Penaeus monodon, three cryoprotectants (dimethyl sulphoxide (DMSO), methanol (MeOH) and ethylene glycol (EG)) at two concentrations (5% and 10%) were examined. Artificial implantation of spermatophores was also carried out to assess the fertilizing ability of fresh and post‐thaw spermatophores. Spermatophores were collected during consecutive regenerations (15‐day intervals) and assessed for qualitative and quantitative changes and also for fertilizing ability by implantation. The mean fertilization rate for artificial insemination using post‐thaw spermatophore was 79.9±3.7%, lower than the fertilization rates observed for artificial implantation using fresh spermatophore and natural mating. Mean hatch rates for fresh spermatophore, frozen‐thawed spermatophore and natural mating were 88.8±0.6%, 87.8±0.4% and 88.3±0.5%, respectively; and there was no difference among the three groups. The mean fertilization rate of spermatophores collected during the first stripping was higher (90.6±0.6) than during the second stripping (85.7±2.6), but the mean hatch rate was not different between the two strippings. The highest mean sperm viability (79.7±0.4%) was obtained from DMSO (5%), with no survival observed in the 10% MeOH treatment. Spermatophore weight, total sperm count and percentage of abnormal sperm were not different between spermatophores collected at the first and second stripping. This is the first study to report high fertilization and hatch rates from cryopreserved spermatophore using artificial implantation of spermatophore before spawning.  相似文献   

An evaluation of the pesera soil erosion model and its application to a case study in Zakynthos, Greece     

M. Tsara  C. Kosmas  M.J. Kirkby  D. Kosma  N. Yassoglou 《Soil Use and Management》2005,21(4):377-385

Abstract. The Pan‐European Soil Erosion Risk Assessment (pesera ) model was evaluated using existing soil erosion data collected under various types of climate, vegetation, landscape and soil conditions. The data used represent a variety of typical Mediterranean land uses such as winter wheat, vines, olives and bare, stony land prevailing in hilly areas. Using this data, the model was calibrated for sediment transport by overland flow and results compared to measured soil erosion values from runoff plots and a watershed on a monthly basis. The performance of the model was assessed statistically, showing that it can be satisfactorily used for predicting soil erosion rates under the conditions included in the study. The overall model estimate including all the available experimental data was 0.69 t ha^?1 yr^?1 with a maximum error of 1.49 t ha^?1 yr^?1. After validation, the model was applied to a small watershed (60 ha) of great ecological importance for the sea turtle Caretta caretta. For this purpose, soil and vegetation maps were compiled from all the necessary data for applying the model. The model was run for three years using daily data from an existing nearby meteorological station. The predicted and measured soil erosion rates for a 7‐month period were 0.31 t and 0.18 t, respectively. Application of the model to each mapping unit showed the over‐riding importance of land use for sediment generation under the given climatic conditions. Bare land, occupying 5.5% of the watershed area, generated up to 69% of the total sediments estimated for the watershed. It is concluded that the pesera model can be used as a regional diagnostic tool under a range of soil, topographic and climatic conditions for identifying the best land use type and vegetation cover to protect hilly areas from soil erosion. The calculated overall root mean square error for the model is 0.06 t ha^?1 yr^?1, compared to a soil erosion rate of 0.04 t ha^?1 yr^?1, which can be tolerated for protecting the area for the sea turtle.  相似文献   

AN APPARATUS FOR ROLLER TUBE TISSUE CULTURE     

Coman DR  Stabler NG 《Science (New York, N.Y.)》1941,94(2450):569-570

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THE DATA NOW REQUISITE IN SOLAR INQUIRIES     

Lockyer JN 《Science (New York, N.Y.)》1886,7(169):386-387

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The effects of experimentally induced fever on the estimated blood flow to and oxygen utilization by the liver and the viscera drained by the portal vein in sheep     

D. N. Kisauzi  B. F. Leek 《Veterinary research communications》1991,15(2):95-105

Intrajugular injection of a purified E. coli lipopolysaccharide induced a biphasic fever in sheep after a latent period of 12 to 20 min. The changes in the blood flow from the liver and from the viscera drained by the portal vein were: (a) in the latent period, decreases in total hepatic blood flow (THF) due to decreased portal venous blood flow (PVF); (b) during the first febrile phase, increases in THF due to increased hepatic arterial blood flow and, (c) in the second febrile phase, increases in THF due to decreased PVF. Although there were large variations in the oxygen supply to the viscera drained by the portal vein and to the liver, there were relatively small or no changes in their oxygen consumption.  相似文献   

Cardiogenic shock and cardiac arrest.     

E C?té 《Veterinary Clinics of North America: Small Animal Practice》2001,31(6):1129-45, v

Severe heart disease may cause hypotension and hypoperfusion, and ultimately circulation may cease altogether. These two clinical syndromes are cardiogenic shock and cardiac arrest, respectively. This review summarizes the causes and clinical features of each, and describes the treatment options available to clinicians managing patients in cardiogenic shock.  相似文献