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71.
Patrick E. Lendrum Joseph M. Northrup Charles R. Anderson Glen E. Liston Cameron L. Aldridge Kevin R. Crooks George Wittemyer 《Landscape Ecology》2018,33(1):157-170
Purpose
Human-mediated landscape changes alter habitat configuration, which strongly structures animal distributions and interspecific interactions. The effects of anthropogenic disturbance on predator–prey relationships are fundamental to ecology, yet less well understood. We determined where predation events occurred for fawn and adult female mule deer from 2008 to 2014 in critical winter range with extensive energy development. We investigated the relationship between predation sites, energy infrastructure, and natural landscape features across contiguous areas experiencing different degrees of energy extraction during periods of high and low intensity development.Methods
We contrast spatial correlates of 286 mortality locations with random landscape locations and mule deer distribution estimated from 350,000 GPS locations. We estimated predation risk with resource selection functions and latent selection difference functions.Results
Relative to the distribution of mule deer, predation risk was lower closer to pipelines and well pads, but higher closer to roads. Predation sites occurred more than expected relative to availability and deer distribution in deeper snow and non-forested habitats. Anthropogenic features had a greater influence on predation sites during the period of low activity than high activity, and natural landscape characteristics had weaker effects relative to anthropogenic features throughout the study. Though canids accounted for the majority of predation events, felids exhibited stronger landscape associations, driving the observed spatial patterns in predation risk to mule deer.Conclusions
The emergence of varied interactions between predation and landscape features across contexts and years highlights the complexity of interspecific interactions in highly modified landscapes.72.
Chretin JD Rassnick KM Shaw NA Hahn KA Ogilvie GK Kristal O Northrup NC Moore AS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(1):141-148
BACKGROUND: The administration of chemotherapy is associated with risk for morbidity. Management of chemotherapy-related morbidity in veterinary oncology has been primarily supportive. HYPOTHESIS: The purpose of this study was to evaluate the effect of prophylactic antimicrobial use on chemotherapy-associated morbidity in dogs with lymphoma or osteosarcoma. ANIMALS: Dogs presenting with histologically confirmed osteosarcoma or lymphoma were eligible. METHODS: Patients were randomized to receive placebo or trimethoprim-sulfadiazine for 14 days after their first doxorubicin chemotherapy. Both owner and clinician were blinded with respect to treatment. Patient assessment included CBC, physical examination and performance, and toxicosis grading on days 7 and 14. Investigated outcomes were hospitalization, suspicion of infection, gastrointestinal toxicity, neutropenia, nonhematologic toxicity, and quality of life. RESULTS: Seventy-three dogs were enrolled; 34 had osteosarcoma, and 39 had lymphoma. Dogs receiving trimethoprim-sulfadiazine (n = 36) had a significantly reduced hospitalization rate (P = .03), nonhematologic toxicity (P = 0.039), grade 2-4 nonhematologic toxicity (P < .0001), grade 2-4 gastrointestinal toxicity (P = .007). and altered performance (P = .015). By group, dogs with osteosarcoma (n = 34) that received the antimicrobial experienced fewer occurrences of nonhematologic toxicity (P = .02) and less severe nonhematologic toxicity (P = .038). Dogs with lymphoma (n = 39) had significant reductions in the occurrence of hospitalization (P = .035), severity of nonhematologic toxicity (P = .036), and alterations of performance (P = .015). CONCLUSIONS: The use of prophylactic trimethoprim-sulfadiazine has benefit in reducing morbidity in dogs with osteosarcoma or lymphoma during the first 14 days after treatment with doxorubicin. 相似文献
73.
L Cattaneo ML Signorini J Bertoli JA Bartolomé NC Gareis PU Díaz GA Bó HH Ortega 《Reproduction in domestic animals》2014,49(6):1028-1033
To describe the epidemiology of cystic ovarian disease (COD), to find possible risk factors associated with the incidence of cysts and to analyse the impact of COD on the reproductive performance of dairy cows, databases from 22 dairy herds from the main dairy region in Argentina were retrospectively evaluated throughout a 3‐year period (2009–2011). A total of 248 COD cases over 9156 parturitions were recorded, resulting in a cumulative incidence rate of 2.7%. Cystic ovarian disease incidence density was lower during the first 100 days post‐partum (DPP) than during later stages of lactation. Seasonality had a significant influence on the disease presentation with higher incidence rates during winter and spring. Cows with a previous diagnosis of clinical mastitis showed 2.72 times more chances of developing ovarian cysts. Cystic cows had longer calving to first service and calving to conception intervals and lower conception rate than controls. 相似文献
74.
75.
Indirect computed tomography lymphangiography with aqueous contrast for evaluation of sentinel lymph nodes in dogs with tumors of the head 下载免费PDF全文
Janet A. Grimes Scott A. Secrest Nicole C. Northrup Corey F. Saba Chad W. Schmiedt 《Veterinary radiology & ultrasound》2017,58(5):559-564
Sentinel lymph node evaluation is widely used in human medicine to evaluate the first lymph node(s) to which a tumor drains. Sentinel lymph node biopsy allows avoidance of extensive lymphadenectomies in cases where the sentinel lymph node is negative for metastasis, thereby reducing patient morbidity. It has been shown that regional lymph nodes are not always the sentinel lymph node, thus identification and sampling of sentinel lymph nodes allows for more accurate staging, which is critical for treatment and prognostication in dogs with cancer. The objective of this prospective, pilot study was to determine if indirect computed tomography (CT) lymphangiography with aqueous contrast agent would successfully allow identification of sentinel lymph nodes in dogs with masses on the head. Eighteen dogs underwent CT lymphangiography. The sentinel lymph node was successfully identified within 3 min of contrast injection in 16 dogs (89%). Compression of lymphatic vessels from endotracheal tube ties and/or the patient's own body weight delayed or prevented identification of sentinel lymph nodes in two dogs (11%). Computed tomography lymphangiography with aqueous contrast can be used successfully to rapidly identify sentinel lymph nodes in dogs with masses on the head. 相似文献
76.
MA Lagares R Ecco NRS Martins LJC Lara JSR Rocha DAR Vilela VM Barbosa PF Mantovani JFV Braga IS Preis VA Gheller PC Cardeal NC Baião 《Reproduction in domestic animals》2017,52(1):67-75
The objective of this study was to detect the reasons of rooster's fertility decrease at 50 weeks of age. Therefore, the reproductive system of broiler breeder roosters was laparoscopic, macroscopic and histopathology evaluated, and a comparison of the anatomical aspect with the sperm analysis and birds’ age was realized. Cobb roosters (n = 59) were distributed into two groups (30 and 50 weeks). Evaluations were performed with laparoscopy, macroscopy and histopathology, and seminal quality, blood serum testosterone concentration and weight were also determined. The old roosters presented smaller testicle size, higher intensity epididymal lithiasis and lower testicle sperm production, compared to the young roosters. The use of the endoscope could easily distinguish a normal‐sized testicle than an atrophic one. Four old roosters with severe testicular atrophy did not show spermatogenesis, although three still had sperm in the ejaculate. This would falsely indicate a wrong diagnosis of normal fertility before the testicular atrophy took place. In conclusion, in addition to the weight increase with age, the testicular atrophy and impairment of sperm production seemed to be the main reason to the decrease in the rooster's fertility at 50 weeks of age. Therefore, the use of the laparoscopy as a way to detect the roosters with testicular atrophy before 50 weeks of age and their removal from them flock could be useful as a diagnostic tool to prevent the birds’ fertility loss. 相似文献
77.
Tetravalent uranium in calcite 总被引:1,自引:0,他引:1
NC Sturchio MR Antonio L Soderholm SR Sutton JC Brannon 《Science (New York, N.Y.)》1998,281(5379):971-973
X-ray absorption spectroscopy and x-ray fluorescence microprobe studies of 35-million-year-old calcite from a Mississippi Valley-type zinc ore deposit indicate substitution of tetravalent uranium for divalent calcium. Thus, tetravalent uranium has a stable location in calcite deposited under reducing conditions. This result validates uranium-series dating methods (including uranium/lead dating) for ancient calcite and shows that calcite provides a sink for uranium in deep groundwater aquifers and anoxic lacustrine and marine basins. 相似文献