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Paul D. McGreevy Alex Brueckner Peter C. Thomson Nicholas J. Branson 《Journal of Veterinary Behavior: Clinical Applications and Research》2010,5(6):318-323
The aim of the current study was designed to explore possible breed differences in a basic behavioral phenotype in dogs. It measured paw use during food-retrieval from a cylindrical, hollow, rubber toy to assess motor laterality (pawedness) in 4 breeds of dogs selected for their morphological differences: 45 greyhounds (males n = 23/females n = 22), 47 whippets (15/32), 46 pugs (15/31), and 45 boxers (17/28). A laterality index was calculated from the use of individual paws to restrain the toy during feeding. An association was found between sex and the laterality index (P = 0.035), reflecting a significant bias for left-paw use by entire male dogs and right-paw use by entire female dogs but no sex difference was found in the mean strength of laterality. No significant association was found between age and the laterality index. No breed difference was found in the laterality index (P = 0.423) or the absolute strength of laterality (i.e., the laterality index without direction, P = 0.259). However, important breed differences in the use of the test device emerged. The frequency of simultaneous use of both paws was lowest in pugs (P < 0.0001). In addition, both brachycephalic breeds (pugs and boxers) took less time than the dolichocephalic breeds (the whippets and greyhounds) to complete the criteria of 100 paw-use scores that was set for the laterality test. The absence of breed differences in the laterality index for paw use suggests that the task is a reliable measure of motor laterality in dogs during a food-retrieval task. 相似文献
135.
Mucinous cholangiocarcinoma was diagnosed in a 14-year-old, castrated male, domestic shorthaired cat with marked peritoneal effusion. Cytological confirmation of malignancy by fluid analysis and fine-needle, ultrasound-guided aspiration of the liver was followed by histological examination of tissue samples obtained at surgery and necropsy. No observed response followed chemotherapy with doxorubicin and carboplatin. Electron microscopy and immunohistochemistry helped to further characterize this unusual tumor. 相似文献
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Veterinary Research Communications - 相似文献
137.
Kavitha Kongara BVSc MVSc PhD Paul Chambers BVSc DVA PhD MRCVS & Craig B Johnson BVSc PhD DVA Dipl ECVA MRCA MRCVS 《Veterinary anaesthesia and analgesia》2009,36(1):86-94
ObjectiveTo compare the effects of morphine, parecoxib, tramadol and a combination of parecoxib, tramadol and pindolol on nociceptive thresholds in awake animals and their effect on glomerular filtration rate (GFR) in dogs subjected to 30 minutes of anesthesia.AnimalsEight adult mixed breed experimental dogs.Study designRandomized, controlled trial.MethodsDogs received 0.05 mg kg?1 acepromazine subcutaneously (SC) as anaesthetic pre-medication. Thirty to sixty minutes later, they received either tramadol 3 mg kg?1 intravenously, (IV), parecoxib (1 mg kg?1 IV), a combination of tramadol 3 mg kg?1 (IV), parecoxib 1 mg kg?1 (IV) and pindolol 5 μg kg?1 (SC), morphine (0.1 mg kg?1 (IV) or 0.9% saline (2 mL). Anaesthesia was then induced with IV propofol to effect (2.9 ± 0.8 mg kg?1) and maintained with halothane in oxygen for 30 minutes. Systolic arterial blood pressure was maintained above 90 mmHg with IV fluids and by adjusting the inspired halothane concentration. Post-treatment nociceptive thresholds to mechanical stimuli, expressed as percent of pre-treatment values, were compared between the treatments to assess the analgesic efficacy of the drugs. Plasma iohexol clearance (ICL), a measure of GFR, was estimated both before and 24 hours after induction of anaesthesia to study the drugs’ effects on renal perfusion. Nociceptive threshold and GFR data were compared using mixed model analysis in sas®9.1.ResultsBoth tramadol and parecoxib produced similar analgesia, which was less than that of morphine. Their combination with pindolol produced analgesia comparable with morphine. None of the test drugs, either alone or in combination, reduced GFR.ConclusionTramadol and parecoxib (either alone or in combination) can increase nociceptive thresholds in awake dogs and have minimal effects on renal perfusion in normotensive dogs subjected to anaesthesia. 相似文献
138.
Carolyn J. Broccardo Gisela Soboll Hussey Lutz Goehring Paul Lunn Jessica E. Prenni 《Journal of Equine Veterinary Science》2014
Cerebrospinal fluid (CSF) is a biofluid that is reflective of overall health. Although proteomic profiling of human CSF has been performed in the context of a variety of disease states, this report represents the first comprehensive proteomic analysis of equine CSF. A total of 320 proteins were confidently identified across six healthy horses, and these proteins were further characterized by gene ontology terms mapped in UniProt, and normalized spectral abundance factors were calculated as a measure of relative abundance. Theses results provide an optimized protocol for analysis of equine CSF and lay the groundwork for future studies involving the study of equine CSF in the context of pathogenic disease states. 相似文献
139.
The acute and chronic toxicities of three benzoylphenyl ureas, diflubenzuron, hexaflumuron and teflubenzuron were assessed under laboratory conditions against two-day-old second (II) instar Desert Locust, Schistocerca gregaria (ForskÅl) nymphs. Following exposure by ingestion of a single precise dose applied to short pieces of spring barley, nymphs were monitored for two moults until the fourth (IV) instar. Analysis of acute response data gave three significantly different LD50 statistics (P < 0·05), 68·0, 26·6 and 0·71 μg per nymph respectively for diflubenzuron, hexaflumuron and teflubenzuron. The probit regression slopes also differed significantly, indicating distinct tolerance distributions for the three compounds, the narrowest response being to diflubenzuron and the widest range of response being to teflubenzuron. The timing of death was found to vary between the compounds; most nymphs died during the first moult following treatment with either hexaflumuron or teflubenzuron. However, the majority of nymphs that died after exposure to diflubenzuron did so after completing the first moult after treatment, but before the second. The mean development times of nymphs during the II and especially third (III) instars were significantly longer (P < 0·05) than those of the controls following exposure to diflubenzuron and hexaflumuron. Teflubenzuron had no significant effect (P < 0·05) on the duration of the II instar. The potential of the three compounds to control S. gregaria populations in the field is discussed with particular reference to the timing and nature of acute and chronic responses. 相似文献
140.
Lucy M.I. Webster Paul C.D. Johnson Aileen Adam Barbara K. MableLukas F. Keller 《Veterinary parasitology》2008
Benzimidazole (BZ) resistance is widespread in nematode parasites of livestock, but very little is known about the levels of BZ resistance in parasites with avian hosts. We investigated BZ resistance in Trichostrongylus tenuis, a nematode parasite of red grouse, Lagopus lagopus scotica. BZ anthelmintics had been in use in this system for up to 15 years, yet existing phenotypic evidence for resistance was inconclusive. We screened 1530 individuals from 14 populations at the principal β-tubulin locus for BZ resistance (isotype 1, residue 200) and 940 of these at two further resistance sites (isotype 1, residue 167; isotype 2, residue 200). No BZ resistant genotypes were found. Alternative mechanisms may be responsible for BZ resistance in this system, or the method and timing of treatments may reduce selection pressure for BZ resistance by creating substantial refugia for susceptible genotypes. 相似文献