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21.
Chantelle Franklin Michael Herrtage Karen Harris Marie-Aude Genain 《Veterinary radiology & ultrasound》2023,64(2):194-200
Humeral intracondylar fissures (HIF) have been predominantly reported in spaniel breeds and proposed to be possible risk factors for humeral condyle fractures (HCF). We hypothesized that the prevalence of incidental HIF in French Bulldogs may be greater than that of other brachycephalic breeds. A retrospective, observational, prevalence study was performed using CT examinations of French bulldogs and other brachycephalic breed dogs presenting for an unrelated condition. Two European College of Veterinary Diagnostic and Imaging-certified radiologists reviewed the images of the humeral condyles of these dogs. A classification system was devised to grade the findings. We considered a Score 1 to be normal, Score 2 to have centralised sclerosis, Score 3 to have a partial fissure and Score 4 to have a complete fissure. A total of 228 elbows were reviewed from 122 dogs. Of this population, 145 elbows were from French Bulldogs, 54 were from Pugs, and the remainder were from a mix of other brachycephalic breeds. The prevalence of HIF (score 3 or 4) in elbows of the French bulldog, pug and other breed groups was 6.9% (CI 2.8–11%), 5.6% (CI 0–11.7%), and 3.4% (CI 0–10.15%), respectively. At a dog level, the prevalence of HIF (score 3 or 4 present in at least one elbow) was found to be 11.8% (CI 4.6–19%) in French Bulldogs, 11.1% (CI 0–22.9%) in Pugs, and 5.26% (CI 0–15%) in the other breed group. There was no significant difference between the breed groups. The inter-reviewer reliability for CT scoring of HIF based on Cohen's weighted kappa was low at 0.19. 相似文献
22.
23.
Pablo M. Vergara Luis O. Meneses Audrey A. Grez Madelaine S. Quiroz Gerardo E. Soto Christian G. Pérez-Hernández Paola A. Diaz Ingo J. Hahn Andrés Fierro 《Landscape Ecology》2017,32(2):279-293
Context
Interactions between landscape-scale processes and fine-grained habitat heterogeneity are usually invoked to explain species occupancy in fragmented landscapes. In variegated landscapes, however, organisms face continuous variation in micro-habitat features, which makes necessary to consider ecologically meaningful estimates of habitat quality at different spatial scales.Objectives
We evaluated the spatial scales at which forest cover and tree quality make the greatest contribution to the occupancy of the long-horned beetle Microplophorus magellanicus (Coleoptera: Cerambycidae) in a variegated forest landscape.Methods
We used averaged data of tree quality (as derived from remote sensing estimates of the decay stage of single trees) and spatially independent pheromone-baited traps to model the occurrence probability as a function of multiple cross-scale combinations between forest cover and tree quality (with scales ranging between 50 and 400 m).Results
Model support and performance increased monotonically with the increasing scale at which tree quality was measured. Forest cover was not significant, and did not exhibit scale-specific effects on the occurrence probability of M. magellanicus. The interactive effect between tree quality and forest cover was stronger than the independent (additive) effects of tree quality and particularly forest cover. Significant interactions included tree quality measured at spatial scales ≥200 m, but cross-scale interactions occurred only in four of the seven best-supported models.Conclusions
M. magellanicus respond to the high-quality trees available in the landscape rather than to the amount of forest per se. Conservation of viable metapopulations of M. magellanicus should consider the quality of trees at spatial scales >200 m.24.
25.
Steven C Zicker Karen J Wedekind Dennis E Jewell 《Veterinary Clinics of North America: Small Animal Practice》2006,36(6):1183-98, v
Nutritional antioxidants have experienced a surge in research and interest in the past 20 years. this surge may be attributed to the improved methodology for investigation as well as the focus on diseases and aging processes related to oxidative stress that lend themselves to opportunistic outcomes. As such, the field of veterinary nutritional antioxidant research is also beginning to yield some interesting results, albeit, small in number compared with laboratory animals and human beings. Nonetheless, this article updates the practitioner on recent advances in research involving nutritional antioxidant applications in companion animals. 相似文献
26.
Rose L. Cherry Kryssa L. Johnson Adrien‐Maxence Hespel Karen M. Tobias Daniel A. Ward 《Veterinary ophthalmology》2019,22(3):353-359
A 2‐year‐old, male castrated German shepherd dog was presented to the University of Tennessee Veterinary Medical Center (UTVMC) with periorbital swelling and conjunctival mucopurulent discharge 2 days following removal of a twig from the medial canthus by the owner. Diagnostic imaging was pursued due to the suspicion of a retrobulbar foreign body (FB). A cylindrical FB approximately 3.0 cm in length and 1.0 cm in diameter with concentric rings, suspected to be wooden material, was identified on computed tomography (CT) imaging. An attempt to remove the FB via a stab incision using ultrasound guidance was unsuccessful, and postmanipulation ultrasound confirmed the FB position was unchanged. An exploratory orbitotomy was performed, using the acquired CT images for guidance in locating the FB; however, the FB was not present at the predicted site. The CT imaging was repeated and showed that the FB had migrated rostrally approximately 3.0 cm, compared to the originally acquired study and its same location during attempted ultrasound‐guided removal. A combination of CT‐guided needle placement and contrast injection was then used with repeat imaging in an attempt to better localize the FB and its soft tissue tract. The dog was taken back into the operating room, and the wooden FB was successfully removed. 相似文献
27.
Feline calicivirus (FCV) is an important and highly prevalent pathogen of cats. It belongs to the family Caliciviridae which includes other significant pathogens of man and animals. As an RNA virus, high polymerase error rates convey upon FCV a high genome plasticity, and allow the virus to respond rapidly to environmental selection pressures. This makes the virus very adaptable and has important implications for clinical disease and its control. Being genetically diverse, FCV is associated with a range of clinical syndromes from inapparent infections to relatively mild oral and upper respiratory tract disease with or without acute lameness. More recently, highly virulent forms of the virus have emerged associated with a systemic infection that is frequently fatal. A proportion of FCV infected cats that recover from acute disease, remain persistently infected. In such cats, virus evolution is believed to help the virus to evade the host immune response. Such long-term carriers may only represent a minority of the feline population but are likely to be crucial to the epidemiology of the virus. Vaccination against FCV has been available for many years and has effectively reduced the incidence of clinical disease. However, the vaccines do not prevent infection and vaccinated cats can still become persistently infected. In addition, FCV strain variability means that not all strains are protected against equally. Much progress has been made in understanding the biology and pathogenesis of this important feline virus. Challenges for the future will necessarily focus on how to control the variability of this virus particularly in relation to emerging virulent strains and vaccination. 相似文献
28.
Cary A Moody G Todd Pharr Joey Murphey Marian B Hughlett Carroll C Weaver Phillip D Nelson Karen S Coats 《Journal of veterinary diagnostic investigation》2002,14(2):113-119
The purpose of this study was to determine whether bovine immunodeficiency virus (BIV) is vertically transmitted in naturally infected dairy cattle. Twenty-two dam/calf pairs from a Mississippi Agriculture and Forestry Experiment Station dairy were the study group. Blood samples were collected following delivery of calves, the peripheral blood leukocytes were purified from these samples, and the leukocyte DNA was used in polymerase chain reactions targeting the pol gene region of the BIV provirus. Southern blotting and hybridization were used to confirm the BIV specificity of the amplified fragments. BIV provirus was detected in 14 of 22 calves (64%), demonstrating vertical transmission. Eight of the calves were disqualified from the final interpretation of transplacental transfer because they may have nursed their mothers prior to blood collection, allowing the possibility of lactogenic transfer of the virus. Transplacental transmission of BIV was identified in 6 of 22 calves (27%). 相似文献
29.
Hansen RA Savage CJ Reidlinger K Traub-Dargatz JL Ogilvie GK Mitchell D Fettman MJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(4):457-463
An 18-week feeding trial was performed to investigate the effects of an omega-3 (n-3) fatty acid-enriched ration on plasma fatty acid concentrations and platelet aggregation in healthy horses. Flaxseed oil served as the source of the n-3 fatty acid alpha-linolenic acid (ALA). Twelve horses were fed dietary maintenance requirements using a complete pelleted ration (80%) and timothy grass hay (20%) for a 2-week acclimation period before being randomly assigned either to a treatment (group 1) or control (group 2) group. Group 2 horses (n = 6) were fed the diet described in the acclimation period, whereas group I horses (n = 6) were fed a 10% flaxseed oil-enriched complete pellet (80%) and grass hay (20%). Biological samples and physical measurements were collected at one point during the acclimation period (week 0) and every 4 weeks thereafter (weeks 4, 8, 12, and 16). Body weight, CBC (including platelet count), plasma fibrinogen. electrolyte (Na, K, and Cl) concentrations, and biochemical profile enzyme activities (aspartate aminotransferase, alkaline phosphatase, gamma-glutamyltransferase, and creatine kinase) did not change markedly with diet. Platelet aggregation was not altered by the supplementation of flaxseed oil in these healthy horses, although increases in plasma cis-polyunsaturated 18-carbon fatty acids C18:3; n-3 (ALA) and C18:2; n-6 (linoleic acid), biologically active C20:5; n-3 (eicosapentaenoic acid [EPA]), and malondialdehyde (MDA) were evident. There were no marked decreases in C20:4; n-6 (arachidonic acid [AA]) or increases in C22:6; n-3 (docosahexaenoic acid [DHA]), signifying that flaxseed oil may have had a high percentage of omega-6 (n-6) fatty acids as well as n-3 fatty acids, and this relatively high n-6: n-3 fatty acid ratio may have affected the biochemical effect of n-3 fatty acids. In healthy horses supplemented with flaxseed oil, platelet aggregation was not altered, which may have been due to the limited biologic effect in healthy subjects or the inability of flaxseed oil to induce the necessary biochemical effect of replacing n-6 fatty acids with n-3 types. 相似文献
30.
Mary E. Gordon PhD Michael L. Jerina BS Randel H. Raub PhD Karen E. Davison PhD J. Kathleen Young PhD 《Journal of Equine Veterinary Science》2008,28(5):289-294
This study tested the hypothesis that feeding an identically formulated, low sugar and starch concentrate in three forms (5-mm extruded [E], 4-mm pellet [P], and 19-mm oval [O]) would affect consumption rate and glucose or insulin responses, or both. Horses received 1.8 kg treatment feed in a randomized, crossover design, with samples taken every 30 minutes for 6 hours for blood glucose and insulin response. Pearson's correlation compared consumption time, insulin and glucose peak, and time to peak insulin and glucose. The pellet (P) elicited a lower (P = .01) glucose concentration at 2.5 hours than O. The pellet also elicited a lower (P = .03) insulin concentration at 5.5 hours than E and O. There were no differences (P > .05) in area under the curve (AUC) insulin, peak insulin, and time to peak insulin for the three treatments. Average insulin concentration was lower (P = .01) for P versus O. There were no differences (P > .05) in average insulin between P and E, nor between O and E. There were no differences (P > .05) in AUC and peak glucose concentration. Time to peak glucose was longer (P = .04) for P versus E. Average glucose concentration was lower (P = .02) for P versus O. Consumption time was longer (P = .03) for O versus P. There was a positive correlation between consumption time and time to peak insulin (r = 0.46, P = .029). Further research on feeding practices, feed forms, and consumption times that affect glycemic response is necessary. 相似文献