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431.
432.
In order to evaluate the effects of short transportation on β‐endorphin, adrenocorticotropic hormone (ACTH) and cortisol changes, 12 healthy stallions of Equidae (Equus asinus and Equus caballus) were studied before and after transportation of 50 km. Blood samples were collected 1 week before transportation in basal conditions, immediately before loading and after transportation and unloading, on their arrival at the breeding station. Compared to basal and before values, donkeys showed an increase in circulating ACTH (P < 0.001) and cortisol (P < 0.0005) levels after transportation and higher ACTH (P < 0.01) levels than horses after transportation. A positive and significant correlation (r = 0.885; P < 0.01) between ACTH and cortisol levels after transportation was found. No significant differences were observed for β‐endorphin levels. Compared to basal and before values, horses showed higher cortisol (P < 0.005) levels after transportation and no significant differences were observed for ACTH and β‐endorphin levels in donkeys. Horses facing forward (direction of travel) showed higher (P < 0.01) β‐endorphin levels after transportation than donkeys; horses facing backward (the opposite direction of travel) showed lower (P < 0.05) ACTH levels after transportation. The results indicate that short transportation induces a preferential activation of the hypothalamus‐pituitary‐axis (HPA), with significant release of ACTH and cortisol in donkeys and only of cortisol in horses, suggesting that transportation for donkeys may be more stressful than horses.  相似文献   
433.
In this study changes in hematochemical parameters, milk composition and yield were investigated in buffaloes during the transition period. A total of 93 buffaloes 113.9 ± 8.03 months old and 535 ± 50 kg average body weight were used. Parity was recorded, blood samples were collected from 80 days pre‐partum until 70 days post‐partum; milk samples were collected from 5 days to 70 days post‐partum. On serum samples, the values of non‐esterified fatty acids, β‐hydroxybutyrate, glucose, cholesterol, triglycerides, aspartate aminotransferase, alanine aminotransferase, gamma‐glutamyltransferase, urea, total proteins were evaluated. On milk, percentage of fat, protein and lactose, along with the somatic cell count (SCC), milk yield and daily milk production (DMP) were assessed. The peripartum period significantly (P ≤ 0.01) influenced all studied parameters with the exception of glucose. Milk fat percentage showed decreasing trend from 10 until 40 days post‐partum; DMP significantly (P ≤ 0.01) increased from 1 day post‐partum until 40 days post‐partum. Milk yield significantly (P ≤ 0.01) decreased in animals over the sixth lactation. Our results confirmed the importance of transit period in buffaloes. Blood parameters and milk composition alterations are crucial to predict the energy balance status of buffaloes in order to improve their management and feed intake during the transition period.  相似文献   
434.
BackgroundBasal serum cortisol (BSC) ≥2 μg/dL (>55 nmol/L) has high sensitivity but low specificity for hypoadrenocorticism (HA).ObjectiveTo determine whether the urinary corticoid:creatinine ratio (UCCR) can be used to differentiate dogs with HA from healthy dogs and those with diseases mimicking HA (DMHA).AnimalsNineteen healthy dogs, 18 dogs with DMHA, and 10 dogs with HA.MethodsRetrospective study. The UCCR was determined on urine samples from healthy dogs, dogs with DMHA, and dogs with HA. The diagnostic performance of the UCCR was assessed based on receiver operating characteristics (ROC) curves, calculating the area under the ROC curve.ResultsThe UCCR was significantly lower in dogs with HA (0.65 × 10−6; range, 0.33‐1.22 × 10−6) as compared to healthy dogs (3.38 × 10−6; range, 1.11‐17.32 × 10−6) and those with DMHA (10.28 × 10−6; range, 2.46‐78.65 × 10−6) (P < .0001). There was no overlap between dogs with HA and dogs with DMHA. In contrast, 1 healthy dog had a UCCR value in the range of dogs with HA. The area under the ROC curve was 0.99. A UCCR cut‐off value of <1.4 yielded 100% sensitivity and 97.3% specificity in diagnosing HA.Conclusions and Clinical ImportanceThe UCCR seems to be a valuable and reliable screening test for HA in dogs. The greatest advantage of this test is the need for only a single urine sample.  相似文献   
435.
In order to investigate the pathogenesis of neosporosis following a primary infection in late pregnancy, cattle were subcutaneously challenged with 5 × 108Neospora caninum (NC1 isolate) tachyzoites at day 210 of gestation and serial necropsies were then carried out at 14, 28, 42 and 56 days post-infection (dpi). No abortions occurred and all the foetuses were viable at the time of euthanasia. There was a high rate of vertical transmission, as parasites were detected by immunohistochemical labelling and PCR in all the foetuses from 28 dpi. Focal necrotic lesions were observed in the placentomes of the placenta from 28 dpi and showed resolution during later time points, denoted by infiltration of inflammatory cells at 42 dpi and fibrosis at 56 dpi. Foetuses at 28 and 42 dpi showed scarce and isolated lesions which are unlikely to represent a threat to foetal viability. No lesions were observed in the foetuses at 14 or 56 dpi suggesting control of the infection and resolution of the lesions by maternal and foetal immune responses. Once infection was established, it could not be cleared from the host and vertical transmission of the parasite occurred in all infected hosts. Parasite was detected in the placenta at 28 dpi, while in previous experimental infections of cattle at day 70 and 140 of gestation using the same challenge model, it was already present at day 14 post infection. This suggests that a change in the maternal immune response plays a crucial role in limiting the initial infection during the last term of pregnancy.  相似文献   
436.
The application of gibberellic acid (GA3) to the whole loquat tree from mid-May to early June and from early August to the onset of flowering, significantly reduced the number of premature flowering shoots per current shoot and per m3 of canopy, and so reduced the total number of panicles per m3 of canopy. The number of vegetative shoots per m3 of canopy was also significantly reduced by applying GA3. The response depended on the concentration applied and produced optimal results at 50 mg l−1. Differences in the number of flowers per panicle and leaves per shoot were not significantly modified by the treatment. Nevertheless, GA3 applied directly to the developing apex near to flower differentiation reduced the number of flowers per panicle by 25–35% and without modifying the morphological characteristics of the panicle. Results suggest that less sprouting of lateral buds was largely responsible for the reduction in flowering intensity caused by GA3. Best treatments reduced thinning costs (60%, approximately) of premature flowering shoots, slightly increased fruit diameter and significantly improved fruit colour and juice quality, thus advancing harvest date.  相似文献   
437.
Reintroduction projects represent viable options for animal conservation. They allow the establishment of new local populations and may contribute to recreating functional networks within a metapopulation. In the latter case, landscape connectivity may be a major determinant of the phase of spread of the reintroduced populations. Here, we deal with an example of a red deer (Cervus elaphus) translocation planned to enable the connection among existing isolated populations of the species in the Italian Alps. Our aim was to assess whether the analysis of landscape suitability and the simulation of dispersal of released individuals could shed light on the actual process of population spread. For these purposes, we adopted a modelling approach using radiotracking data to develop a habitat suitability map. On the basis of this map, we simulated the dispersal of the animals after release and we then compared the simulation results with the outcome of null models and with the observed population redistribution. The results suggest that the spread of the subpopulation was easier north-westward than southward. Taking into account landscape suitability, our simulations produced a reliable estimate of the ease of colonization of the valleys neighbouring the release-site and they allowed the identification and validation of a potential pathway for animal dispersal. The suitability model based on the monitoring of individuals in the earliest phase of establishment shed light on the spread of the population and on its potential connections with other deer subpopulations.  相似文献   
438.
Platelet derived growth factor receptor (PDGFR)α and PDGFRβ are tyrosine kinase receptors that are overexpressed in 70–80% of human osteosarcomas (OSAs) and may be suitable therapeutic targets for specific kinase inhibitors (TKIs). Canine OSA shows histopathological and clinical features similar to human OSA, and is considered an excellent model in comparative oncology. This study investigated PDGF-A, PDGF-B, PDGFRα and PDGFRβ expression in 33 canine OSA samples by immunohistochemistry and in seven primary canine OSA cell lines by Western blot and quantitative PCR analysis.Immunohistochemical data showed that PDGF-A and PDGF-B are expressed in 42% and 60% of the OSAs analysed, respectively, while PDGFRα and PDGFRβ were expressed in 78% and 81% of cases, respectively. Quantitative PCR data showed that all canine OSA cell lines overexpressed PDGFRα, while 6/7 overexpressed PDGFRβ and PDGF-A relative to a normal osteoblastic cell line. Moreover, in vitro treatment with a specific PDGFR inhibitor, AG1296, caused a dose- and time-dependent decrease in AKT phosphorylation. Collectively, these data show that PDGFRs/PDGFs are co-expressed in canine osteosarcomas, which suggests that an autocrine and/or paracrine loop is involved and that they play an important role in the aetiology of OSA. PDGFRs may be suitable targets for the treatment of canine OSA with a specific TKI.  相似文献   
439.
Blood flow changes in cranial abdominal vessels are important contributing factors for canine hepatic disease. This prospective, experimental, pilot study aimed to evaluate cardiac‐gated, phase contrast magnetic resonance angiography (PCMRA) as a method for characterizing blood flow in canine major cranial abdominal vessels. Eleven, healthy, adult beagle dogs were sampled. Cardiac‐gated, phase contrast magnetic resonance angiography of the cranial abdomen was performed in each dog and blood flow was independently measured in each of the major cranial abdominal vessels by three observers, with two observers recording blood flow values once and one observer recording blood flow values three times. Each dog then underwent ultrasonographic examination of the liver with fine needle aspirations and biopsies submitted to cytologic and histologic examination. The mean absolute stroke volume and velocity were respectively 9.6 ± 1.9 ml and –11.1 ± 1.1 cm/s for the cranial abdominal aorta, 2.1 ± 0.6 ml and –6.6 ± 1.9 cm/s for the celiac artery, and 2.3 ± 1.0 ml and –7.9 ± 3.1 cm/s for the cranial mesenteric artery. The mean absolute stroke volume and velocity were respectively 6.7 ± 1.3 ml and 3.9 ± 0.9 cm/s for the caudal vena cava and 2.6 ± 0.9 ml and 3.2 ± 1.2 cm/s for the portal vein. Intraobserver reliability was excellent (intraclass correlation coefficient > 0.9). Interobserver reproducibility was also excellent (intraclass correlation coefficient 0.89–0.99). Results of liver ultrasonography, cytology, and histopathology were unremarkable. Findings indicated that cardiac‐gated, phase contrast magnetic resonance angiography is a feasible technique for quantifying blood blow in canine major cranial abdominal vessels. Blood flow values from this sample of healthy beagles can be used as background for future studies on canine hepatic disease.  相似文献   
440.
The aim of the present study was to fill the void in data related to hematological and biochemical parameters of donkey foals. Whole-blood and plasma samples were obtained from 16 Amiata donkey foals at birth, at 24 and 48 hours, and at 1, 2, 3, 4, 6, and 8 weeks of age. RBC, WBC, hemoglobin concentration (Hgb), mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, platelet count, glucose, creatinine, blood urea, triglycerides, total cholesterol, total bilirubin, aspartate aminotransferase, γ-glutamyl transferase, creatine-phosphokinase, alkaline phosphatase, total calcium, potassium, sodium, phosphorus, and albumin were measured. Similar to equine foals, values of RBC, Hgb, and Hct decreased significantly after the first 48 hours of life in Amiata donkey foals, reaching values similar to adult donkeys. No changes were found for mean corpuscular volume and mean corpuscular hemoglobin concentration during the study period. The WBC was low at birth when compared with subsequent measurements, but significantly increased in the subsequent surveys. Platelet count was lower in the first week, with a secondary peak 2 weeks later, and then a decline again up to the eighth week. In agreement with equine foals, electrolyte concentrations, triglycerides, and total cholesterol did not show significant differences. Creatinine, total bilirubin, and blood urea showed a trend similar to RBC, Hgb, and Hct. For the first time, data of hematological and biochemical parameters in Amiata donkey foals are provided.  相似文献   
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