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91.
Uses of game resources are under constant debate. One such debate focuses on hunting tourism and its contributions to rural economics. To prioritize future investment and inform policy decisions, it is necessary to identify the full economic consequences of the operation of hunting tourism companies in rural areas. However, the true economic significance of these typically small-scale companies is not apparent when examined on an industrial scale. These companies may nevertheless serve as a sustainable solution to local-scale rural challenges. In this article, the regional economic significance of hunting tourism is estimated for the East Lapland sub-region of northern Finland through the use of Computable General Equilibrium simulation models. Although these models are known to effectively evaluate short- and long-term regional economic effects of industries such as tourism, they have not previously been applied to evaluate hunting tourism. 相似文献
92.
Surgical treatment of mammary carcinomas in dogs with or without postoperative chemotherapy 下载免费PDF全文
This retrospective study identified prognostic factors associated with survival; and compared survival data in 94 canine mammary carcinoma (MCA) dogs treated with surgery (n = 58), or surgery and adjunct chemotherapy (n = 36), and a subset of dogs with poor prognostic factors. On multivariate analysis independent predictors of median survival time (MST) were clinical stage, lymphatic invasion (LI; present 179 days; none 1098 days), ulceration (present 118 days; none 443 days) and surgical margins (incomplete 70 days; complete 872 days). Complete surgical margins were associated with MST in dogs with stages 1–3 MCA (incomplete 68 days; complete 1098 days) and dogs with LI (incomplete 70 days; complete 347 days). There was no statistically significant improvement in MST in dogs with advanced disease (stage 4 or LI) treated with adjunctive chemotherapy (chemotherapy 228 days; none 194 days); although five dogs with complete surgical margins that received mitoxantrone and carboplatin had a mean survival of 1139 days. 相似文献
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Oral infection of goats with Mycobacterium avium subsp. hominissuis (MAH) resulted in a large variety of granulomas in organized gut-associated lymphatic tissues and intestinal lymph nodes. To characterize the cellular composition of granulomas, CD4+, CD8+, γδ, B lymphocytes and plasma, CD25+, CD68+, MHC-II+, Ki67+ and endothelial cells were labeled in consecutive frozen sections by immunohistochemistry and acid fast bacilli (AFB) by Kinyoun stain. Granulomas with extensive necrosis, little mineralization and variable numbers of AFB surrounded by many CD4+ T cells, but only few epitheloid macrophages were observed in severely sick goats at 2–3 mpi. They were interpreted as exuberant immune reaction. Organized granulomas with very few AFB were seen in clinically healthy goats at 13 mpi. The necrotic cores were surrounded by a zone of granulomatous infiltrate with many epitheloid macrophages and few lymphocytes. This zone was initially wide and highly vascularized and became progressively smaller. It was enclosed by an increasing layer of connective tissue. All organized granulomas were surrounded by compartimentalized tertiary lymphoid tissue. The granulomas in experimental infection of goats with MAH reflect the heterogeneity of lesions seen in mycobacterial infections of humans and ruminants and are therefore valuable for comparative research. 相似文献
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Effect of urea supplementation on performance and safety in diets of Dorper crossbred sheep 下载免费PDF全文
B. Wang T. Ma K.‐D. Deng C.‐G. Jiang Q.‐Y. Diao 《Journal of animal physiology and animal nutrition》2016,100(5):902-910
This study was conducted to evaluate the efficacy and safety of dietary urea in sheep rations having a 50:50 concentrate:roughage ratio. Sixty‐four Dorper × thin‐tailed Han crossbred ram lambs with an average body weight of 30.8 (±0.02) kg were randomly divided into four groups of 16 sheep each, and each group was fed one of the following diets: a basal diet (CON), or CON supplemented with 0.5% (0.5UTM), 1.5% (1.5UTM) or 2.5% (2.5UTM) urea. Growth performance, carcass characteristics, non‐carcass offals, meat quality and peptic tissue lesions were assayed. The average daily weight gains for CON, 0.5UTM, 1.5UTM and 2.5UTM were 216, 218, 200 and 170 g, respectively, with the CON and 0.5UTM groups higher than 2.5UTM group (p < 0.05). Sheep from the 2.5UTM treatment had a significantly lower dry matter intake (1.29 kg/day) than those from the CON and 0.5UTM treatments (1.42 and 1.43 kg/day, p < 0.05), and the feed conversion ratio in the 2.5UTM group was the highest (p < 0.05). Carcass characteristics, including shrunk body weight, empty body weight, hot carcass weight, dress percentage, and the absolute or relative weight (% body weight) of heart, liver, spleen, lung and kidney, were not altered by the treatments (p > 0.05). The muscular pH of 2.5UTM was higher than that of CON (5.68 vs. 5.52, p < 0.05), and shear force in 0.5UTM was lower compared with CON and 2.5UTM (p < 0.05). The anatomical structure lesions in kidneys became more serious with the increasing dietary urea concentrations, with the 2.5UTM animals showing the most severe lesions compared with CON animals. Therefore, supplementary urea as a non‐protein nitrogen source for sheep should not exceed 1.5% of ration having a 50:50 concentrate:roughage ratio to ensure efficacy and safety. 相似文献
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E. S. Pereira A. B. R. Carmo M. R. G. F. Costa A. N. Medeiros R. L. Oliveira A. P. Pinto M. S. S. Carneiro F. W. R. Lima A. C. N. Campos S. P. Gomes 《Journal of animal physiology and animal nutrition》2016,100(6):1090-1096
In this study, we evaluated the requirements of calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na) and potassium (K) for sheep hair growth. Experimental diets contained different levels of metabolizable energy [ME; 0.96, 1.28, 1.72, 2.18 and 2.62 Mcal/kg of dry matter, (DM), corresponding to 4.23, 5.64, 7.58, 9.61 and 11.55 MJ/kg DM]. The lambs' hair (n = 48) at 2 months of age presented an average body weight (BW) of 12.05 ± 1.81 kg. At the beginning of the experiment, eight animals were slaughtered as a reference group to estimate the initial empty body weight and body composition. Net mineral requirements (g/day) ranged from 0.73 to 0.71 g of Ca, 0.51 to 0.49 g of P, 0.026 to 0.026 g of Mg, 0.16 to 0.19 g of Na and 0.15 to 0.13 g of K for animals with a BW ranging from 15 to 30 kg and a daily gain of 100 g. The results of this study indicate that the net macromineral requirements for weight gain in Morada Nova lambs are different from the values commonly recommended by the Agricultural and Food Research Council. 相似文献
99.
以西番莲品种‘台农1号’为实验材料,通过电镜扫描技术比较观测TeMV和PWV侵染与健康西番莲的叶片、幼嫩果实外果皮组织形态结构,分析测定其叶片生理生化变化,研究西番莲病毒侵染对西番莲叶片和幼嫩果实外果皮组织结构和生理生化的影响。结果表明:TeMV与PWV侵染后,西番莲植株叶片的海绵组织细胞间隙缩小,发生成团堆积状排列,栅栏组织细胞萎缩,呈不规则长条形;幼嫩果实外表皮组织中石细胞层发生严重断裂,排列松散,海绵层细胞变得松散,且发生较严重的木质化现象;叶片与幼嫩果实外表皮表面纹理粗糙、褶皱,气孔保卫细胞萎缩,气孔周围组织皱缩、粗燥;感病果实外果皮表面上的腺毛凸起无序。病毒侵染后,感病植株第1~3叶的蔗糖含量较第4~6叶的高23.11%;健康叶片则相对平衡,降低了淀粉积累、PG酶、纤维素酶与PPO酶活性,提高了感病植株第1~3叶的α-淀粉酶、GS酶与POD酶活性。西番莲受TeMV与PWV侵染后,植株叶片第1~6叶营养物质分配不平衡,相关物质的合成分解与抗氧化防御酶系统受伤害,叶片与果实组织形态结构受到不同程度的损坏,植株正常吸收功能遭到破坏。 相似文献
100.
为建立‘南核1号’核桃组培快繁体系,以带芽茎段为外植体,开展外植体采集时间、初代诱导、继代增殖和生根培养各阶段试验。结果表明,全年中4-5月为最佳外植体采集时间;最佳诱导培养基为DKW+6-BA 1.0 mg/L+NAA 0.1mg/L,诱导率为66.7%;最佳增殖培养基为DKW+6-BA 1.0 mg/L+IBA 0.01mg/L,增殖率为63.3%,增殖系数为3.83;生根采用二步诱导生根法,先在附加IBA 6.0mg/L的1/2DKW中暗培养,再转移到1/4DKW中光培养,生根率为46.6%。 相似文献