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1.
甘肃东方蜜蜂的形态特征研究   总被引:7,自引:0,他引:7  
通过测定甘肃2个不同样点的4群东方蜜蜂发现,甘肃蜜蜂种群内遗传变异丰富,种群中许多形态性状特征表现出较明显的地理变异性;蜜蜂个体增大、体色变深,具体是:前翅长、前翅宽、背板3,4宽;后腿长、蜡镜长、蜡镜宽、蜡镜间距、腹片3,6的长和宽逐渐增加;背板3,4、小盾片的色素度逐渐加深。这些均具有生态适应意义。  相似文献   
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The objective of this study was to evaluate the effect of collagenase and two final dimethylformamide (DMF) concentrations (4% and 7%) on alpaca frozen-thawed sperm quality. A total of 25 ejaculates from 5 alpaca were obtained using electroejaculation. Each individual ejaculate was evaluated and then diluted 4:1 in a solution of 1 mg/ml collagenase in HEPES-TALP medium and incubated for 4 min at 37°C. Subsequently, samples were diluted in TRIS-fructose-citric acid-egg yolk and cooled to 5°C. Then, each sample was divided in two aliquots and DMF at final concentration of 4% or 7% was added, equilibrated for 1 hr at 5°C and frozen over liquid nitrogen vapours. A Kruskal–Wallis test was used to evaluate the sperm morphometry, and Completely Random Block designs were used to analyse sperm motility, viability, membrane function and acrosome status. After collagenase incubation, none of the samples showed thread formation, and sperm parameters were preserved. Non-progressive motile sperm were higher (p < .05) in equilibrated samples (4% DMF: 31.8 ± 8.3% and 7% DMF: 36.3 ± 11.8%) compared to raw (10.1 ± 4.3%) and frozen-thawed semen (4% DMF: 9.7 ± 1.8% and 7% DMF: 7.5 ± 3.2%). Sperm membrane function, membrane integrity and intact acrosomes were higher (p < .05) in raw semen (40.1 ± 12.2%, 94.6 ± 3.2% and 91.3 ± 8.1%) compared to frozen-thawed samples (4% DMF: 19.8 ± 4.7%, 53.2 ± 2.7%, 65.7 ± 8.7% and 7% DMF: 20.4 ± 4.5%, 54.1 ± 1.4%, 64.6 ± 9.1%). Length of the sperm head was lower in frozen-thawed samples, being statistically different with 4% DMF compared to pre-freezing samples. The ratio between acrosome and head areas was greater (p < .05) in frozen-thawed samples. Incubation of raw alpaca semen with collagenase decreased the thread formation without affecting sperm quality. Frozen of collagenase treated alpaca semen with 4% or 7% DMF did not preserve the sperm parameters in thawed samples.  相似文献   
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Insects are currently being considered as a novel protein source for animal feeds, because they contain a large amount of protein. The larvae of Tenebrio molitor (TM) have been shown to be an acceptable protein source for broiler chickens in terms of growth performance, but till now, no data on histological or intestinal morphometric features have been reported. This study has had the aim of evaluating the effects of dietary TM inclusion on the performance, welfare, intestinal morphology and histological features of free‐range chickens. A total of 140 medium‐growing hybrid female chickens were free‐range reared and randomly allotted to two dietary treatments: (i) a control group and (ii) a TM group, in which TM meal was included at 75 g/kg. Each group consisted of five pens as replicates, with 14 chicks per pen. Growth performance, haematological and serum parameters and welfare indicators were evaluated, and the animals were slaughtered at the age of 97 days. Two birds per pen (10 birds/treatment) were submitted to histological (liver, spleen, thymus, bursa of Fabricius, kidney, heart, glandular stomach and gut) and morphometric (duodenum, jejunum and ileum) investigations. The inclusion of TM did not affect the growth performance, haematological or serum parameters. The morphometric and histological features were not significantly affected either, thus suggesting no influence on nutrient metabolization, performance or animal health. Glandular stomach alterations (chronic flogosis with epithelial squamous metaplasia) were considered paraphysiological in relation to free‐range farming. The observed chronic intestinal flogosis, with concomitant activation of the lymphoid tissue, was probably due to previous parasitic infections, which are very frequently detected in free‐range chickens. In conclusion, the findings of this study show that yellow mealworm inclusion does not affect the welfare, productive performances or morphological features of free‐range chickens, thus confirming that TM can be used safely in poultry diets.  相似文献   
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湖北神农架中蜂的数值分类研究   总被引:2,自引:3,他引:2  
 通过测定湖北神农架6 个不同样点的18群东方蜜蜂,每群15只工蜂,每只蜜蜂样共38个形态特征,测定的性状特征的数据进行因素分析,集合分析和区辨分析;形态性状与生态环境因子相关性分析;并与周边省份东方蜜蜂的相关数据进行比较,发现: 神农架蜜蜂种群内遗传变异丰富,种群中许多形态性状特征表现出较明显的地理变异性;蜜蜂个体增大、体色变深, 具体是:前翅长、前翅宽、背板3,4宽; 后腿长、蜡镜长、蜡镜宽、蜡镜间距、腹片3,6的长和宽逐渐增加;而背板3,4的色素度、小盾片的色素度逐渐加深。神农架东方蜜蜂种群形态性状的多态性、多型性及其生态地理变异式样,均具有生态适应意义  相似文献   
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长白山东方蜜蜂形态特征研究*   总被引:1,自引:0,他引:1  
 通过测定长白山6个不同样点17群东方蜜蜂的38个形态特征并采用计算机进行数据分析,得出长白山东方蜜蜂可分为3个类群。同邻近国家(日本、韩国)及中国部分地区的东方蜜蜂形态数据进行分析发现,长白山东方蜜蜂与日本、韩国的东方蜜蜂归于1个类群,由于长白山的气候及自然地理条件而形成多个小的生态区域,长白山东方蜜蜂在小区域内自成繁殖体系,各个生态区域间蜜蜂个体体色差异较大,体型大小差异不大。  相似文献   
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獭兔睾丸组织形态观察   总被引:1,自引:0,他引:1  
獭兔是一种典型的经济动物,它既是毛皮动物又可食用,普遍应用于人类生产生活。目前已有研究报道了多种哺乳动物生精周期研究,但很少有关于獭兔的报道。本实验对2只完全性成熟的健康獭兔进行睾丸结构,生精周期相对频率,支持细胞效率研究。獭兔睾丸经石蜡包埋,HE染色以便进行组织形态学观察。不同的生殖细胞组合分析显示30%的曲精小管显示两个或两个以上的生精上皮周期阶段。獭兔生精周期阶段频率(%)分别为:阶段1:(15.5±2);阶段2:(14.0±1);阶段3:(11.5±1);阶段4:(8.5±1);阶段5:(10.5±1);阶段6:(18.5±2);阶段7:(13.0±1);阶段8:(8.5±1)。支持细胞效率(圆形精子:支持细胞=7:1)。本研究结果表明獭兔的生精效率较其他哺乳动物高。  相似文献   
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Navicular bones from the four limbs of 95 horses, classified in 9 categories, were studied. The effects of age on navicular bone morphometry and histomorphometry were estimated, after adjustment of the data to even out the effects of front and rear limbs, morphometrical type, sex, weight, and size.All the external measurements of the navicular bone decreased significantly with increasing age. From the histomorphometrical data, cortical bone volume decreased with age in most horses, whereas cancellous bone volume and, in particular, the marrow spaces increased. The increase in the cancellous bone volume could have resulted from tunnelling of the internal part of the cortex, which converted it progressively into a porous trabecular-like structure. Trabecular bone volume also decreased with age and the trabecular lattice changed dramatically to become disconnected in aged horses. These observations corresponded closely to those reported for ageing of the skeletal system in humans.However, in sporting horses, the navicular cortical bone volume increased with age and the cancellous bone volume decreased. Exercise appeared to have decreased bone resorption and increased bone formation at the endocortical junction. The cancellous bone architecture was also improved, in that the trabecular lattice and trabecular bone volume remained unchanged in aged sporting horses. Our findings confirmed that exercise may be good practice to prevent age-related bone loss.  相似文献   
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