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171.
While it is widely understood that local abundance of benthic invertebrates can greatly influence the distribution and abundance of wetland birds, no studies have examined if wetland landscape context can mediate this relationship. We studied the influence of wetland food abundance and landscape context on use of agricultural wetlands by wintering dunlin (Calidris alpina) and killdeer (Charadrius vociferus) in the Willamette Valley of Oregon, USA, over two winters (1999-2000, 2000-2001) of differing rainfall and subsequent habitat distribution. We monitored bird use (frequency of occurrence and abundance) at a sample of wetlands differing in local food abundance (density and biomass) and landscape context [adjacent shorebird habitat (defined as ha of wet habitat with less than 50% vegetative cover and within a 2-km radius) and nearest neighbor distance]. We evaluated predictive models for bird use using linear regression and the Cp criterion to select the most parsimonious model. During the dry winter (2000-2001), dunlin exhibited greater use of sites with higher invertebrate density and biomass but also with more adjacent shorebird habitat and closest to a wetland neighbor. However, neither landscape context nor food abundance were important predictors of dunlin use during the wet winter (1999-2000). Use of sites by killdeer was unrelated to either local food abundance or landscape context measures during both winters. Our findings contribute to a growing recognition of the importance of landscape structure to wetland birds and highlight a number of implications for the spatial planning and enhancement of wetlands using a landscape approach. 相似文献
172.
Cuadrado C Grant G Rubio LA Muzquiz M Bardocz S Pusztai A 《Journal of agricultural and food chemistry》2002,50(15):4371-4376
The nutritional effects in the rat of raw lentil meal or its fractions have been evaluated in three feeding trials. Growth, gain/feed ratio, apparent N digestibility, and N retention were significantly (p < 0.05) reduced by the inclusion of whole lentil meal, dehulled lentil meal, or ethanol-extracted lentil meal as the sole source of protein in the diet. Pure lentil lectin and lectin-depleted albumin proteins had no significant negative effect on nutritional performance. In contrast, growth, gain/feed ratio, protein conversion efficiency, N digestibility, and N retention were significantly (p < 0.05) reduced by diets containing lentil globulins or lentil hulls. The poor nutritional quality of raw lentil meal for rats is therefore likely to be primarily due to the combined effects of these two components. 相似文献
173.
Susan E Orosz 《Veterinary Clinics of North America: Exotic Animal Practice》2002,5(1):31-48, v-vi
The avian skeleton is significantly different from the mammalian skeleton, and these differences are important when providing fracture repair and postoperative care for the avian patient. Successful repair depends on an understanding of fracture management and healing and of the anatomical, physiologic, and behavioral concerns of avian patients. Having knowledge of fracture repair without an understanding of the unique needs of avian patients' results in a disappointing treatment response. 相似文献
174.
Judith A. Hudson DVM PhD Susan T. Finn-Bodner DVM MS Joan R. Coates DVM Donald C. Sorjonen DVM MS Stephen T. Simpson DVM MS James C. Wright DVM PhD Jan E. Steiss DVM PhD Nancy R. Cox DVM PhD Dana M. Vaughn DVM PhD Starr C. Miller BS Scott A. Brown DVM PhD Phillip D. Garrett DVM MS 《Veterinary radiology & ultrasound》1995,36(6):542-547
Doppler ultrasonography of the spinal cord was performed in 34 normal, anesthetized dogs following hemilaminectomy. This study was part of an investigation to evaluate the efficacy of a 21-aminosteroid compound and high dose methylprednisolone for the treatment of spinal cord trauma. Grey-scale images of the canine spinal cord were similar to those described for the spinal cord of people. Doppler waveforms of intraparenchymal spinal arteries exhibited high end diastolic blood flow velocities, indicating low resistance to flow. Doppler values (mean ± SD) for arteries immediately ventrolateral to the central canal were: Peak Systolic Velocity = 5.78 ± 2.5 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Systolic/Diastolic ratio = 169 ± 0.19, Pulsatility Index = 0.53 ± 0.09, and Resistance Index = 0.4 ± 0.06. 相似文献
175.
Thirty-eight carbamates and thiocarbamates were evaluated for the production of delayed neurotoxicity in the mature White Leghorn hen. Several thiocarbamates including phenyl-N-ethylthiocarbamate and s-2,3-dichloroallyl diisopropylthiocarbamate (diallate) produced symptoms of severe delayed neurotoxicity following repeated oral administration. The results of these experiments do not preclude the possibility that neurotoxic carbamates and organophosphorous compounds may share a common site of action. 相似文献
176.
177.
CANINE BRAIN ANATOMY ON MAGNETIC RESONANCE IMAGES 总被引:1,自引:1,他引:0
Susan L. Kraft DVM Patrick R. Gavin DVM PHD Lyle R. Wendling MD Venkat K. Reddy BVSC PHD 《Veterinary radiology & ultrasound》1989,30(4):147-158
Magnetic resonance (MR) images of the canine brain were acquired during investigation of dogs with neurologic disease. A paramagnetic contrast medium was used for enhancement. MR provided images with excellent contrast between grey and white matter, as well as brain tissue and cerebrospinal fluid. Good resolution and anatomic detail of the canine brain were obtained. A series of images was compiled and labelled as a reference for MR anatomy of the canine brain. 相似文献
178.
David Ruslander Antony S. Moore BVSc MVSc John M. Gliatto Deborah L'Heureux Susan M. Cotter 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(4):299-301
Cytosine arabinoside (AraC) was administered as a continuous IV infusion to 15 dogs with malignant lymphoma at a dose of 300 mg/m2 /d for 2 consecutive days. Dogs were re-examined 7 d after treatment for response to therapy and for hematologic toxicity. Regardless of response, all dogs were started on combination chemotherapy at this time. Other toxicities were reported by owners. No dog responded objectively to Ara-C treatment, although 1 dog with circulating lymphoblasts had partial regression of lymphadenopathy but persistent blastemia. Thrombocytopenia (platelet count < 200,000/μL) 7 days posttreatment was the most commonly encountered hematologic toxicity, occurring in 10 of 14 dogs. Three of these 10 dogs were also mildly neutropenic (neutrophil counts of 2000 to 3000 cell/μL). Nonhematologic toxicity occurred in 8 of 15 dogs and was principally gastrointestinal in nature and mild in severity. Cytosine arabinoside at a dose of 300 mg/m2 /day was not considered an active drug for the induction of remission in dogs with lymphoma. 相似文献
179.
Charles R. Pugh DVM MS Phillip J. Johnson BVSc MS Gregory Crawley DVM MS Susan T. Finn DVM MS 《Veterinary radiology & ultrasound》1994,35(3):183-188
The equine shoulder region is difficult to investigate by conventional imaging modalities. Diagnostic ultrasound has proven valuable for investigation of soft tissue injuries of the human shoulder. In a horse with shoulder lameness, the authors employed diagnostic ultrasound to augment the use of conventional radiography. A defect in the subchondral bone layer of the medial humeral tuberosity, with adjacent bony fragments were clearly identified with ultrasound. Ultrasound was used for initial evaluation of the bicipital tendon and bursa. The technique was subsequently used to follow and evaluate the post-operative condition of the proximal cranial humerus, bicipital tendon and bursa in this patient. The bicipital regions of 2 immature and 3 adult normal horses were also examined with to illustrate the normal ultrasonographic anatomy of the cranial shoulder region. 相似文献
180.
Susan M. Newell DVM Mary B. Mahaffey DVM MS Royce E. Roberts DVM MS Ana Patricia Garcia DVM Anita R. Stampley DVM 《Veterinary radiology & ultrasound》1994,35(3):217-220
Laryngeal adenocarcinoma was diagnosed in a 5-year-old golden retriever dog with no history of respiratory or pharyngeal difficulties. Radiographically the basihyoid bone was destroyed by the neoplasm, and extensive soft tissue mineralization ventral to the larynx was also present. Complete surgical resection was not possible due to diffuse involvement of the tongue and larynx. Cobalt-60 teletherapy was used for treatment of the tumor. There was no clinical evidence of tumor regrowth at approximately 12 months post treatment. This is an unusual example of primary laryngeal neoplasia due to the absence of clinical respiratory abnormalities and the aggressive destruction of the basihyoid bone. 相似文献