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71.
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   
72.
Deer are recognized as hosts of Mycobacterium bovis and assessing the role of wild cervids in perpetuating tuberculosis among cattle has motivated extensive research on several continents. In this paper, the histopathology of lymph node and lung tuberculous granulomas in M. bovis positive British deer is presented. The overall aim was to seek further insights into the potential for onward transmission from infected deer to other species, including cattle. Samples were obtained from an extensive survey of wild mammals in South-West England and from statutory tuberculosis surveillance. M. bovis culture-positive samples were characterised microscopically as to their stage of lesion advancement, number of acid-fast bacilli and granuloma encapsulation. Seventy percent of the deer developed granulomas containing far greater numbers of M. bovis bacilli than typically reported in cattle. Red and fallow deer had the largest number of poorly encapsulated granulomas often containing many hundreds of bacilli. The results are consistent with infected wild British deer being a potential source of environmental contamination and onward transmission to other species. However, further work on levels of bacillary shedding is required before this can be confirmed.  相似文献   
73.
一发病情况 本镇李某购进太湖雏鹅1000只,在一面积60余平方米的塑料薄膜棚内育雏。该棚没有门窗,四面塑料薄膜下垂到地面,用砖头和木板压紧,内装有6只250W红外线灯作取暖用。雏鹅在11日龄前一切正常,12日龄时有4只死亡,以后每天都有死亡,至3月5日现场检查发现,棚内共死亡56只。  相似文献   
74.
Objective  To determine ocular distribution and toxicity of a single injection of intravitreal triamcinolone acetonide (TA) in normal horses.
Animals studied  Six adult horses, donated to North Carolina State University.
Procedures  Six horses were injected intravitreally with either 10, 20, or 40 mg ( n  = 2 each) of TA. The opposite eye of each horse was injected with balanced salt solution (BSS). Ocular toxicity was assessed by biomicroscopy, tonometry, indirect ophthalmoscopy, and electroretinogram. Aqueous humor (AH), vitreous humor (VH), and plasma samples were collected. Horses were euthanized 7 or 21 days after injection and eyes enucleated for histopathology. TA concentrations in AH, VH, and plasma were measured by HPLC.
Results  Three control eyes and one TA eye developed inflammation after injection or collection of AH. Positive bacterial cultures ( Corynebacterium spp., Staphylococcus spp., and Streptococcus spp.) were obtained from three of these eyes. Other than transient corneal edema in TA injected eyes, which resolved by 7 days after injection, no other changes were observed. TA crystals were visible within the vitreous body. No evidence of TA toxic effect was noted on histopathology. TA was detected in all AH and VH samples from treated eyes following injection. Drug was not detected in the plasma.
Conclusions  There was no evidence of overt toxicity from intravitreal TA in normal horses and a single intravitreal injection resulted in TA ocular levels for 21 days. However, the risk for bacterial infections with intravitreal injection or anterior chamber aspirations in horses is high. Use of topical and systemic antibiotics after injection is recommended.  相似文献   
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77.
[目的 ]构建重大动物疫病暴发流行预警指标体系。[方法 ]以禽流感和口蹄疫为例,采用文献调研法和德菲尔专家咨询法中的专家会议法初拟重大动物疫病预警体系的框架和指标;应用德菲尔专家咨询法评价预警指标的重要性、可操作性;应用组合权重法比较各指标综合影响的大小,并将指标分类。[结果 ]筛选出禽流感和口蹄疫预警预报一级指标6项(易感动物、饲养管理和免疫情况等)以及二级指标14项(免疫效果、环境消毒、温度等),并将指标分为三类(关键指标、重要指标和一般指标)。[结论 ]初步构建了重大动物疫病暴发流行预警指标体系。  相似文献   
78.
An 8-year-old female African wild dog (Lycaon pictus) from a zoo in Gyeonggi province, Republic of Korea presented with a 3.0 x 2.0 x 2.5 cm in size, smooth-surfaced, solitary pedunculated mass protruding into the uterine lumen. Microscopically, the mass was covered with epithelium, contained endometrial gland tissue, and was dilated in the vascularised stroma. Within the mass, there was extensive diffuse haemorrhage with several blood vessels apparently plugged with fibrin. At the base of the mass, the spaces lined with epithelium near the attachment of the stalk were interpreted to be glandular structures. There were segments of cuboidal epithelium found on the surface of the mass, which was similar to the lining the uterus. A diagnosis of an endometrial polyp was made based on the gross and histology findings. This is the first case report of a spontaneous endometrial polyp in an African wild dog.  相似文献   
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80.
A new hemolytic assay for bovine complement is presented. Using this assay we found a significant reduction in bovine serum complement activity during the acute phase of anaplasmosis, and an increase in the sensitivity of the red blood cells (RBC) to bovine complement lysis in vitro. The new hemolytic test is performed with bovine RBC, rabbit anti-bovine RBC serum and bovine serum complement. An isotonic sucrose Tris-buffered saline solution of ionic strength 0.094 and pH 7.2 was found to be adequate for this test. The titres obtained with this new assay, which uses autologous RBC, are comparable with those obtained using the guinea pig RBC assay. The finding of a reduction in bovine serum complement during anaplasmosis may be suggestive of a mechanism responsible for the pathology of this disease.  相似文献   
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