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51.
Medical records from 111 threatened bald eagles (86%, Haliaeetus leucocephalus) and peregrine falcons (14%, Falco peregrinus) admitted to the Wildlife Center of Virginia from 1993 to 2003 were reviewed to identify submitters, causes of morbidity and mortality, and final disposition. Half of all patients admitted were submitted by the Virginia Department of Game and Inland Fisheries personnel. Trauma was the most common reason for presentation in bald eagles (70%) and peregrine falcons (81%). Additional causes of morbidity and mortality in bald eagles included toxicoses (10%), infectious diseases (8%), and orphaned young (1%). Neoplasia was confirmed in two trauma cases, suggesting underlying disease might have increased susceptibility to acute traumatic injuries. Peregrine falcons were also admitted for infectious disease (19%). The most frequent infectious disease for both species was West Nile virus. Thirty-nine percent of patients were released back into the wild, 28% were euthanized, 20% died, and 13% were placed in captivity. Postrelease monitoring that would determine whether rehabilitated animals survived to contribute to threatened populations was not performed in this study.  相似文献   
52.
Although bats of the genus Pteropus are important ecologically as pollinators and natural hosts for zoonotic pathogens, little is known about their basic physiology. Hematology and plasma biochemistries were determined from wild-caught flying foxes (Pteropus giganteus) in northern India (n=41). Mean lymphocyte differential count was higher for juveniles than adults. Mean platelet count was lower than previously reported. No hemoparasites were observed. No differences were observed between plasma biochemistry values of male and female bats, juveniles and adults, or lactating and nonlactating females. Variation in aspartate aminotransferase (AST) was seen based on body condition score. Blood urea nitrogen and cholesterol concentrations were lower in P. giganteus than other mammalian groups, but were consistent with those reported from other Pteropus species. Alanine aminotransferase and AST concentrations were higher than those reported for Pteropus vampyrus, a closely related species. This study provides basic physiologic information that can be used in future health and disease studies of Indian flying foxes.  相似文献   
53.
The riverscape perspective recognizes the heterogeneous habitat types within the stream corridor as a single, integrated ecological unit operating across spatial scales. Although there is ample evidence that the riverscape notion is appropriate in understanding the physical phenomena of stream corridors, significantly less attention has focused on its ecological ramifications. To this end, we surveyed riverscape habitat variables and bird community characteristics in the Champlain Valley of Vermont, USA. From the data collected, we used information theoretic methodology (AICc) to model relationships between bird community attributes and key habitat variables across the riverscape. Our models with the greatest support suggest that riverine bird communities respond to a suite of characteristics; representing a variety of riverscape habitats at the in-stream, floodplain, and riparian levels. Channel slope, drainage area, percent conifers, and in-stream habitat condition were among the most influential variables. We found that piscivores are potentially important indicators of riverscape condition, responding to a host of variables across the riverscape. Our results endorse a holistic approach to assessing and managing the mosaic of patches in the riverscape and suggest that a riverscape approach has significant conservation potential.  相似文献   
54.
The spores (conidia) of the bean anthracnose fungal pathogen, Colletotrichum lindemuthianum, adhere to the aerial parts of plants to initiate the infection process. In previous studies we have shown that the Colletotrichum spores are surrounded by a fibrillar spore coat, comprising several major glycoproteins. Previous evidence showed that a monoclonal antibody (UB20) that recognised these glycoproteins was able to inhibit adhesion of spores to a hydrophobic surface. In this paper we have further studied the role of the spore coat in adhesion, germination and fungal development by studying the effects of UB20 and protease treatment of spores. The latter treatment has previously been shown to remove the spore coat. Spores germinate on glass, polystyrene and water agar, however, appressoria only develop on glass or polystyrene, showing a requirement for a hard surface. Removal of the spore coat with protease inhibits adhesion at 30 min, before the secretion of ECM glycoproteins. Protease treatment also inhibits the development of appressoria and reduces pathogenicity on leaves. Incubation of spores with the MAb UB20 inhibits adhesion at 30 min, but does not affect appressorium formation or pathogenicity. The results suggest that an intact spore coat has two functions; it is required for adhesion to a hydrophobic surface and for the detection of a hard surface necessary for appressorium formation. We suggest that contact with a hard surface, rather than adhesion, is the key event leading to appressorium formation.  相似文献   
55.
Horses are known to acquire small airway disease (SAD), an allergen-induced naturally occurring syndrome of reversible obstructive lung disease accompanied by airway hyperresponsiveness and increased inflammatory cell numbers on bronchoalveolar lavage (BAL). This disorder has received scant attention in young racehorses. The purpose of the present report was to examine the effect of BAL eosinophilia in young racehorses on clinical examination, BAL, hematology, airway responsiveness, and on pulmonary function at rest and after a standardized exercise challenge. Five (3 males, 2 females; age 2.6 ± 0.9 years) with a history of respiratory compromise and BAL eosinophil differential count <5% and 6 controls (4 males, 2 females; age 3.5 ± 1.0 years) training and performing to expectation with normal BAL cell differential (eosinophils < 1%) were studied. Respiratory system clinical examination was performed and expressed as a clinical score. Arterial blood gas measurements, CBC, and pulmonary function testing were performed at rest. Pulmonary mechanics measurements were repeated 1 hour and 20 hours after a standardized treadmill exercise challenge. Incremental histamine inhalation challenge was performed and the concentration of histamine effecting a 35% decrease in dynamic compliance (PC35CDyn) was determined. Significant differences were noted between and controls with regard to clinical score ( P = .01), blood eosinophils ( P = .04), BAL cell count ( P = .04), BAL macrophage differential ( P = .04), PC35CDyn ( P = .008), and tidal volume and respiratory rate at 20 hours following exercise challenge ( P = .05). We conclude that pulmonary eosinophilia and airway hyperresponsiveness are manifest in some young horses without overt airway obstruction at rest. We speculate that these may be early events in the natural progression of heaves.  相似文献   
56.
57.
Using a kinetic turbidimetric assay based on the binding of serum glycoprotein to concanavalin A the acute phase reaction has been detected in dogs. Raised levels of glycoprotein were found in dogs which had undergone surgery, had been treated with bacterial endotoxin and had various inflammatory conditions.  相似文献   
58.
A 36 year (1951–1986) record of water temperatures in Mississippi catfish ponds is synthesized from relationships with existing air temperature records. Multiple regression analysis is used to produce the following predictor equations for morning and afternoon pond temperatures: morning pond temperatures = 2.218 + 0.062(max air temp, day before) + 0.285(min air temp, same day) + 0.561 (afternoon pond temp, day before) (1) afternoon pond temperatures
= 2.071 - 0.068(min air temp, same day) + 0.651 (morning pond temp, same day) + 0.373(max air temp, same day) (2)
The derived pond temperature record is analyzed to produce annual average regimes; daily average, maximum, and minimum temperatures with standard deviations; and probabilities at 10 levels of Occurrence through the year and for each individual month. Applications for the aquaculture industry are presented and evaluated.  相似文献   
59.
60.
Veterinary Research Communications - Obesity is considered the most common nutritional disease of dogs. Even though overt obesity is more likely to impair health, even moderately overweight dogs...  相似文献   
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