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51.
In contrast to other mammals, the large variation in dog sizes is not accompanied by any significant genetic re-organization. In order to study the relationship between body mass, limb length and the functional anatomical muscle parameters of the canine hind limb, a large dataset comprising of muscle masses, optimal muscle fibre lengths and physiological cross-sectional area's (PCSA) were acquired for twenty-five muscles in ten dogs of sizes varying between 20 kg and 52 kg. The potential of body mass and limb length for reliably scaling individual muscle masses, optimal muscle fibre lengths and PCSA's were examined. For the majority of the muscles of the canine hind limb, neither body mass nor limb length were reliable scaling parameter for either muscle masses, PCSA's and optimal fibre length. These results indicate the need of a breed-specific approach to musculoskeletal modelling in future canine musculoskeletal research.  相似文献   
52.
We examined hunters’ perceptions of fauna to see if expert hunters and other hunters perceive wildlife abundance similarly. We used cultural consensus analysis (CCA) to assess the knowledge of 25 hunters in the Bolivian Amazon about the abundance of 38 animals. CCA indicated highly shared beliefs among hunters concerning wildlife abundance (average agreement = .62). However, expert hunters (as judged by their reported successful hunts of rare species, having hunted recently, and consuming more game in their diet) perceived more animals as abundant than did non-experts, although they all shared the same model. Since the expert hunters did not always agree on which species was more abundant, they had low cultural knowledge scores in CCA results. These experts may be unwilling to curtail hunting efforts on key species that they perceive to be abundant.  相似文献   
53.
This retrospective case series evaluates survival outcome of 94 dogs with high metastatic risk mast cell tumours (MCT). Patients were treated with a cytotoxic chemotherapy protocol or the tyrosine kinase inhibitor masitinib, in the presence of gross disease or as an adjunct to surgical resection of the primary tumour. In patients presenting with metastatic disease, surgical resection of the primary tumour with adjunctive therapy with any chemotherapy incurred a significant survival advantage [median survival time (MST): 278 days] compared to patients receiving chemotherapy without surgical excision of the primary tumour (MST: 91 days, P < 0.0001). Patients with a surgically excised Patnaik grade II tumour and high Ki‐67 in the absence of metastatic disease treated with vinblastine and prednisolone showed a significantly longer survival (MST: 1946 days) than those treated with masitinib (MST: 369 days, P = 0.0037). Further prospective case‐controlled clinical trials of high‐risk MCTs are required to make precise evidence‐based treatment decisions for individual patients.  相似文献   
54.
A nine‐year‐old intact female domestic shorthair cat was evaluated for paraparesis, ataxia and severe spinal hyperaesthesia. Neurological examination indicated a T3‐L3 spinal cord segment lesion. Computed tomography of the thoracolumbar and lumbosacral vertebral column was performed. This showed contiguous smooth new bone formation ventral and lateral to the vertebrae extending from the cranial thoracic area to the lumbosacral junction and appearing similar to canine diffuse idiopathic skeletal hyperostosis. There was also marked dorsolateral stenosis of the vertebral canal at the level of T4‐T5 because of degenerative changes of the facet joints. To the authors’ knowledge, this is the first published report of feline diffuse idiopathic skeletal hyperostosis.  相似文献   
55.
  1. The aim of this study, comprising two experiments, was (1) to determine in Experiment 1 the relationship of incremental dietary P (phosphorus) content on precaecal digestible P in male broilers and (2) to determine in Experiment 2 the precaecal P digestibility of various inorganic P sources at marginal levels of P supply.

  2. In Experiment 1, a total of 260 male Ross 308 broilers were divided into groups of 10 birds per pen resulting in 8 replicates for treatment 1 and 6 replicates for treatments 2–4. Experimental diets were formulated to contain 4 incremental concentrations of digestible P by means of increasing concentrations of monocalcium phosphate (MCP). In the second experiment, 480-d-old male Ross 308 broilers were divided in groups of 12 birds per pen resulting in 16 replicates for the basal diet and 6 replicates for each test diet. A total of 4 inorganic P sources, MCP, monodicalcium phosphate (MDCP), dicalcium phosphate (DCP) and defluorinated phosphate (DFP) were added to the basal diet to determine the precaecal P digestibility. Three of the 4 inorganic P sources (MCP, MDCP and DCP) represented a mix of batches from different producers. At the end of both experiments, the chyme of the posterior part of the small intestine was collected. Digestibility of P and Ca was determined using titanium dioxide as indigestible marker.

  3. In Experiment 1, a reduction in precaecal digestibility of P was observed above an estimated precaecal digestible dietary P concentration of 4.8 g/kg.

  4. The precaecal P digestibility of the tested inorganic P sources in Experiment 2 was 78.3% for MCP, 59.0% for DCP, 70.7% for MDCP and 31.5% for DFP.

  相似文献   
56.
Tendons regenerate poorly due to a dense extracellular matrix and low cellularity. Cellular therapies aim to improve tendon repair using mesenchymal stem cells and tenocytes; however, a current limitation is the low proliferative potential of tenocytes in cases of severe trauma. The purpose of this study was to develop a method useful in veterinary medicine to improve the differentiation of Peripheral Blood equine mesenchymal stem cells (PB-MSCs) into tenocytes. PB-MSCs were used to study the effects of the addition of some growth factors (GFs) as TGFβ3 (transforming growth factor), EGF2 (Epidermal growth factor), bFGF2 (Fibroblast growth factor) and IGF-1 (insulin-like growth factor) in presence or without Low Level Laser Technology (LLLT) on the mRNA expression levels of genes important in the tenogenic induction as Early Growth Response Protein-1 (EGR1), Tenascin (TNC) and Decorin (DCN). The singular addition of GFs did not show any influence on the mRNA expression of tenogenic genes whereas the specific combinations that arrested cell proliferation in favour of differentiation were the following: bFGF2 + TGFβ3 and bFGF2 + TGFβ3 + LLLT. Indeed, the supplement of bFGF2 and TGFβ3 significantly upregulated the expression of Early Growth Response Protein-1 and Decorin, while the use of LLLT induced a significant increase of Tenascin C levels. In conclusion, the present study might furnish significant suggestions for developing an efficient approach for tenocyte induction since the external administration of bFGF2 and TGFβ3, along with LLLT, influences the differentiation of PB-MSCs towards the tenogenic fate.  相似文献   
57.
The present study describes the pathogenesis of infection of chicks with a new avian reovirus strain, belonging to the so-called enteric reovirus strains (ERS) that is capable of causing central nervous system signs in SPF white leghorns. After intramuscular (IM) or oral inoculation birds were either observed for clinical signs or sacrificed for macroscopic, histological and virological examination for 21 days. Virus isolation was performed on the brain, leg muscle, hock joint, liver and spleen. For the detection of viral antigen the immunohistochemistry (IHC) technique was performed on the caudal part of the cerebrum, spinal cord including spinal ganglia and right N. Ischiadicus. High mortality (79% in 7 days) was seen in birds that were inoculated IM. Survivors were depressed and stayed small until the end of the experiment. One bird had tremor and showed torticollis at 9 days after IM inoculation. Birds that were inoculated orally were depressed from day 4 and stayed small until the end of the experiment. One bird showed a torticollis at 10 days after inoculation. After both IM and oral inoculation ERS was isolated from the brain between 3 and 10 days after inoculation. Other examined organs were positive for virus isolation from day 1 or 5 until day 21. IHC revealed viral antigen positive cells in the Plexus chorioideus (plexus epithelial cells or cells within the underlying connective tissue) and in a spinal ganglion. The results indicate that the pathogenesis of ERS infection in chickens bears some resemblance with that of the mammalian reoviruses serotype 1 in mice.  相似文献   
58.
The aim of this study was to investigate the effects of treatment with medroxyprogesterone acetate (MPA) on canine adenohypophyseal function. Five Beagle bitches were treated with MPA (10mg/kg, every 4 weeks) and their adenohypophyseal function was assessed in a combined adenohypophyseal function test. Four hypophysiotropic hormones (CRH, GHRH, GnRH, and TRH) were administered before and 2, 5, 8, and 11 months after the start of MPA treatment, and blood samples for determination of the plasma concentrations of ACTH, cortisol, GH, IGF-1, LH, FSH, prolactin, alpha-MSH, and TSH were collected at -15, 0, 5, 10, 20, 30, and 45 min after suprapituitary stimulation. MPA successfully prevented the occurrence of estrus, ovulation, and a subsequent luteal phase. MPA treatment did not affect basal and GnRH-induced plasma LH concentrations. The basal plasma FSH concentration was significantly higher at 2 months after the start of MPA treatment than before or at 5, 8, and 11 months after the start of treatment. The maximal FSH increment and the AUC for FSH after suprapituitary stimulation were significantly higher before treatment than at 5, 8, and 11 months of MPA treatment. Differences in mean basal plasma GH concentrations before and during treatment were not significant, but MPA treatment resulted in significantly elevated basal plasma IGF-1 concentrations at 8 and 11 months. MPA treatment did not affect basal and stimulated plasma ACTH concentrations, with the exception of a decreased AUC for ACTH at 11 months. In contrast, the maximal cortisol increment and the AUC for cortisol after suprapituitary stimulation were significantly lower during MPA treatment than prior to treatment. MPA treatment did not affect basal plasma concentrations of prolactin, TSH, and alpha-MSH, with the exception of slightly increased basal plasma TSH concentrations at 8 months of treatment. MPA treatment did not affect TRH-induced plasma concentrations of prolactin and TSH. In conclusion, the effects of chronic MPA treatment on adenohypophyseal function included increased FSH secretion, unaffected LH secretion, activation of the mammary GH-induced IGF-I secretion, slightly activated TSH secretion, suppression of the hypothalamic-pituitary-adrenocortical axis, and unaffected secretion of prolactin and alpha-MSH.  相似文献   
59.
BACKGROUND: Canine splenic hemangiosarcoma (HSA) is a fatal malignancy, and most affected dogs die within a few months of diagnosis. Most dogs present with signs from tumor rupture, resulting in hemoabdomen and intra-abdominal dissemination. The abdomen is also the main site of disease recurrence. HYPOTHESIS: Intraperitoneal (IP) administration of doxorubicin will delay or prevent intra-abdominal tumor recurrence and prolong survival in dogs with HSA. ANIMALS: Fourteen dogs with splenic HSA. METHODS: A prospective, unmasked, uncontrolled clinical trial. After staging of disease status and splenectomy, pegylated liposomal encapsulated doxorubicin was administered intraperitoneally (1 mg/kg body weight) every 3 weeks for 4 cycles. All dogs were monitored for recurrence of HSA. Samples of plasma and abdominal fluid were collected for measurement of doxorubicin concentration and pharmacokinetic analysis. Nonlinear mixed-effect modeling was used to describe the pharmacokinetics of liposomal doxorubicin administered IP. RESULTS: All 14 dogs died, 12 because of HSA and 2 from other causes. Postmortem examination was performed on 12 dogs. All 12 dogs died because of HSA-related causes and had hepatic metastases and hemoabdomen. The IP-treated dogs had fewer serosal, mesenteric, and omental metastases than historical controls treated with systemic doxorubicin. Results of the postmortem examination and pharmacokinetic analysis confirmed that IP delivery of doxorubicin resulted in an effective drug concentration with a clearance comparable with that after i.v. delivery. CONCLUSIONS AND CLINICAL IMPORTANCE: IP pegylated liposomal encapsulated doxorubicin administration did not prevent intraabdominal recurrence of HSA in dogs.  相似文献   
60.
Recurrent airway obstruction (RAO) is a common condition in stabled horses characterized by small airway inflammation, airway neutrophilia and obstruction following exposure of susceptible horses to mouldy hay and straw and is thus regarded as a hypersensitivity reaction to mould spores. However, the role of immunoglobulin E antibodies (IgE) in the pathogenesis of RAO is unclear. We hypothesized that the number of cells with receptor-bound IgE in bronchoalveolar lavage fluid (BALF) and IgE levels in serum would be higher in RAO-affected than in healthy horses living in the same environment. Therefore, IgE-positive (+) cells were identified by immunocytochemistry on cytospins from BALF and counted. IgE levels against the mould extracts Aspergillus fumigatus (Asp. f.) and Alternaria alternata (Alt. a.) and the recombinant mould allergen Aspergillus fumigatus 8 (rAsp f 8) were measured by enzyme-linked immunosorbent assay (ELISA) in the sera of seven RAO-affected and 22 clinically healthy mature horses housed in the same conventional stable environment. After correcting for the number of neutrophils, there were no significant differences in IgE+ cells on cytospins from BALF between both groups of horses (5% versus 7%, P > 0.1). Serum IgE levels against the mould extracts were significantly higher in RAO-affected than in clinically healthy horses [median = 119 versus 66 relative ELISA units (REU), P < 0.05]. Furthermore, significantly more RAO-affected than healthy horses had detectable serum IgE against the recombinant allergen rAsp f 8 (4/7 and 3/22, respectively, P < 0.05). Age had no significant effect on BALF cell ratios or on specific serum IgE levels. These results show that high IgE levels against mould antigens are associated with RAO under controlled environmental conditions but ranges of mould-specific serum IgE levels overlapped too much between diseased and clinically healthy animals to be of any diagnostic value. Further studies are needed to assess whether IgE-mediated reactions contribute to the pathogenesis of RAO.  相似文献   
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