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71.
陇县“天然林资源保护工程”一期实施使森林资源从恢复性增长进一步向质量提高转变,生态状况明显改善,水土流失明显减少,生物多样性明显增加;林区经济社会进一步向和谐发展转变,提供职工就业岗位,基本解决转岗就业问题,为林区群众提供大量劳务取酬机会,社会保障全面提升,林区民生明显改善,社会和谐稳定.文章分析了陕西省陇县“天然林资源保护工程”一期的林业自然概况,总结了天保一期工程实施的主要成效,讨论了天保一期工程实施的主要问题,总结了天保一期工程实施的主要经验. 相似文献
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本试验从健康的鸡盲肠内容物中筛选出具有较高抑菌活性的病源拮抗菌JM-11菌株,经形态、生理生化及16S rDNA序列鉴定此菌为枯草芽孢杆菌(Bacillus subtilis subsp. subtilis)。经耐受胃肠道环境及胆盐试验,结果表明,JM-11菌株能耐受0.3%的胆盐环境,在pH为3.0的人工胃液中能够很好的存活。利用抗生素打乱雏鸡肠道菌群后,饲喂致病性大肠杆菌来制作腹泻模型。经益生菌JM-11对腹泻雏鸡的治疗试验结果显示,JM-11能显著降低腹泻雏鸡粪便中的大肠杆菌的数量(P<0.01),增加乳酸菌的数量(P<0.01),提高雏鸡免疫器官指数(P<0.05),对雏鸡具有安全无毒的作用。 相似文献
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Y. H. A. Elewa O. Ichii S. Otsuka Y. Hashimoto Y. Kon 《Anatomia, histologia, embryologia》2014,43(4):265-272
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
76.
全球范围内鸡蛋消费量持续增长,其中大部分需求量增长来自亚洲的6个国家. 据世界蛋品协会统计分析师Windhorst教授称,截至2015年,世界鸡蛋需求量将比2005年增长1 200万t,从而达到7 090万t(表1). 相似文献
77.
Johnson LK Liebana E Nunez A Spencer Y Clifton-Hadley R Jahans K Ward A Barlow A Delahay R 《Veterinary journal (London, England : 1997)》2008,175(3):409-412
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
78.
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
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
79.
Shimmura T Suzuki T Hirahara S Eguchi Y Uetake K Tanaka T 《British poultry science》2008,49(4):396-401
1. The objective of the present study was to examine the behaviour of laying hens in single-tiered aviaries with and without outdoor areas with particular reference to the proportion of each behaviour and the ways it changed. 2. In all, 144 interbred cross layers (WL/RIR cross-breed) were used. At the age of 16 weeks, the hens were divided at random into two groups and moved to single-tiered aviary (SA) and free-range systems (FR, SA with in addition an outdoor range area covered with clover) with 18 hens per pen. Behavioural observations were conducted before, during and after access to the range. 3. All behaviours using the beak (eating, grazing, drinking, preening, aggressive pecking, feather pecking, litter pecking, object pecking and mate pecking) were recorded as pecking behaviour. 4. While most of the FR hens spent their time outside foraging, the proportion of hens eating, preening, litter pecking, object pecking, aggressive pecking and feather pecking was higher in SA than in FR hens. 5. The proportion of hens performing pecking behaviour of all types was very similar in SA (61.7 +/- 2.0%) and in FR (64.0 +/- 0.8%). The proportion of hens performing overall pecking behaviour increased as pre-laying sitting decreased. 6. The proportion of hens feather pecking decreased in FR during access to range and a similar tendency was found for aggressive pecking. 7. In conclusion, the total proportion of hens pecking was almost the same regardless of whether an outdoor area was provided or not, but the incidence of different types of pecking behaviour differed between SA and FR. The risk of feather pecking in FR may be lower when an outdoor grazing area is provided, although further testing on a larger scale would be essential. 相似文献
80.