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961.
Previously, the structure of the adult goat parotid salivary glands (PGs) was studied. However, little information was elucidated of the juvenile ones. This study aimed to clarify the correlations between the structure of goats' PGs and the nature of food intake among milk‐suckling kids (MSKs) and diet‐fed goats (DFGs). The secretory endpieces of the goats' PGs are of the pure serous type. The serous cells in MSKs showed apical accumulation of numerous secretory granules (SGs) of smaller size and of more intense positive periodic acid‐Schiff reaction. Ultrastructurally, most of the SGs in the DFGs contained peripherally located inclusions that showed dense reaction products for acid phosphatase. In MSKs, the PGs showed less‐developed basal infoldings, sparseness of the inter‐cellular inter‐digitations, fewer inter‐cellular canaliculi and microvilli and also less‐developed myoepithelial cells with fewer and shorter cytoplasmic processes. In conclusion, the less‐developed membrane specializations and myoepithelial cells, as well as the accumulated SGs in the PGs of MSKs, suggest that it secretes less saliva with a little secretory activity than that of DFGs, which may be correlated with the reduced masticatory activity.  相似文献   
962.
963.
Bovine coronavirus (BCoV) is one of the main causes of neonatal calf diarrhoea. Several diagnostic assays have been employed to detect the presence of the virus in stool samples from calves. Despite this, the frequency of BCoV infection among Brazilian and even South American cattle herds has yet to be well characterised. This study describes the occurrence of BCoV infection among calves from dairy and beef herds in four Brazilian states. A total of 282 stool samples from 1 to 60-day-old calves were evaluated for the presence of BCoV by a semi-nested (SN) PCR assay. The animals were from herds (n = 23) located in three geographical regions in Brazil (south, southeast, and center-west). The specific BCoV amplicon was detected in 15.6% (44/282) of the faecal specimens examined, of which 95.4% (42/44) were from diarrhoeic and 4.6% (2/44) from asymptomatic calves. The specificity of the SN-PCR amplicons was evaluated by restriction fragment length polymorphism (RFLP) analysis. The results show that the BCoV is widespread, mainly among calves from 16 to 30-days-old (p = 0.0023), and verify the association between BCoV infection and clinical signs of diarrhoea (p = 0.005). These findings emphasise the importance of this virus in enteric infections of Brazilian cattle herds.  相似文献   
964.
Background: Canine pulmonary fibrosis (CPF) occurs most commonly in West Highland White Terriers. The differing incidences of CPF among dog breeds suggest that genetic factors contribute to its pathophysiology. Pulmonary fibrosis in humans is associated with mutations in the gene coding for lung surfactant protein C (SP-C) ( SFTPC ).
Hypothesis/Objectives: To investigate the histopathologic changes and SP-C composition and genetic structure in dogs with CPF.
Animals: Five dogs with PF, 2 dogs with other lung diseases, and 3 healthy dogs.
Methods: Lung tissue from dogs with clinically suspected CPF and 5 control cases was analyzed histopathologically. Bronchoalveolar lavage fluid (BALF) collected postmortem from 3 terriers with histopathologically confirmed pulmonary fibrosis and the 5 controls were analyzed by Western blots, and the exons of SFTPC were sequenced for 2 dogs with PF and 1 dog with other lung disease.
Results: SP-C could not be detected in BALF of 1 dog with PF, although SP-B was present. A mutation was detected in SFTPC exon 5 of this dog. From 2 dogs with PF and in all 5 control dogs SP-B and SP-C were detected in BALF.
Conclusions: Taken together, the results indicate that canine and human lung fibrosis share histopathologic features and that analysis of SP-C and its gene in a larger set of dogs with PF is warranted.  相似文献   
965.
966.
A seven-year-old miniature dachshund was presented with a large contaminated bite wound centred on the left costal arch. Survey radiographs revealed a pneumomediastinum, a mid-body fracture of the left 11th rib and luxation of the xiphisternum. The compromised skin, ribs, xiphisternum, diaphragm and abdominal wall were surgically debrided. This resulted in a large combined thoracic and abdominal wall defect. The thoracic cavity was closed by diaphragmatic advancement. The abdominal wall defect was partially closed by advancing local abdominal musculature. A cranial abdominal mid-line defect remained and was repaired using two sheets of lyophilised porcine small-intestinal submucosa. Dehiscence of the skin exposing the SIS graft was seen but the abdominal repair remained intact. Eighteen months after the initial injury, the dog remained clinically well and no associated complications were reported.  相似文献   
967.
We explored observed risk factors and drivers of infection possibly associated with African swine fever (ASF) epidemiology in Uganda. Representative sub-populations of pig farms and statistics were used in a case-control model. Indiscriminate disposal of pig viscera and waste materials after slaughter, including on open refuse dumps, farm-gate buyers collecting pigs and pig products from within a farm, and retention of survivor pigs were plausible risk factors. Wire mesh-protected windows in pig houses were found to be protective against ASF infection. Sighting engorged ticks on pigs, the presence of a lock for each pig pen and/or a gate at the farm entrance were significantly associated with infection/non-infection; possible explanations were offered. Strict adherence to planned within-farm and community-based biosecurity, and avoidance of identified risk factors is recommended to reduce infection. Training for small-scale and emerging farmers should involve multidimensional and multidisciplinary approaches to reduce human-related risky behaviours driving infection.  相似文献   
968.
969.
This study presents a multi-disciplinary decision-support tool, which integrates geo-statistics, social network analysis (SNA), spatial-stochastic spread model, economic analysis and mapping/visualization capabilities for the evaluation of the sanitary and socio-economic impact of livestock diseases under diverse epidemiologic scenarios. We illustrate the applicability of this tool using foot-and-mouth disease (FMD) in Peru as an example. The approach consisted on a flexible, multistep process that may be easily adapted based on data availability. The first module (mI) uses a geo-statistical approach for the estimation (if needed) of the distribution and abundance of susceptible population (in the example here, cattle, swine, sheep, goats, and camelids) at farm-level in the region or country of interest (Peru). The second module (mII) applies SNA for evaluating the farm-to-farm contact patterns and for exploring the structure and frequency of between-farm animal movements as a proxy for potential disease introduction or spread. The third module (mIII) integrates mI–II outputs into a spatial-stochastic model that simulates within- and between-farm FMD-transmission. The economic module (mIV) connects outputs from mI–III to provide an estimate of associated direct and indirect costs. A visualization module (mV) is also implemented to graph and map the outputs of module I–IV. After 1000 simulated epidemics, the mean (95% probability interval) number of outbreaks, infected animals, epidemic duration, and direct costs were 37 (1, 1164), 2152 (1, 13, 250), 63 days (0, 442), and US$ 1.2 million (1072, 9.5 million), respectively. Spread of disease was primarily local (<4.5 km), but geolocation and type of index farm strongly influenced the extent and spatial patterns of an epidemic. The approach is intended to support decisions in the last phase of the FMD eradication program in Peru, in particular to inform and support the implementation of risk-based surveillance and livestock insurance systems that may help to prevent and control potential FMD virus incursions into Peru.  相似文献   
970.
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