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71.
72.
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
73.
云南东方蜜蜂形态特征与环境因子相关性的研究 总被引:4,自引:0,他引:4
云南东方蜜蜂种群内遗传变异丰富 ,每个形态性状特征均具有丰富的多态性 ,种群间具多型性 ,且种群中许多形态性状特征表现出较明显的地理变异性[1~ 3 ] 。从滇南 -滇中 -滇西北 ,随纬度或海拔的增加 ,形态特征变异的总趋势是 :蜜蜂个体增大、体色变深。具体是 :1.前翅长、宽 ,背板 3、 4宽 ;2 .后腿长 ,蜡镜长、宽 ,蜡镜间距 ,腹片 3、 6的长和宽逐渐增加 ;3.背板 3、 4的色素度 ,小盾片的色素度逐渐加深。云南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 :与云南东方蜜蜂分布区的气候特点相适应 ,而且还与海拔高度和纬度的变化有着密切的适应关系 相似文献
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Effects of different levels of sanguinarine on antioxidant indices,immunological responses,ileal microbial counts and jejunal morphology of laying hens fed diets with different levels of crude protein 下载免费PDF全文
M. Bavarsadi A. H. Mahdavi S. Ansari‐Mahyari E. Jahanian 《Journal of animal physiology and animal nutrition》2017,101(5):936-948
This study was carried out to assess the effects of different levels of sanguinarine on antioxidant indices, immunological responses, serum biochemical parameters, ileal microbial counts and jejunal morphology of laying hens fed on diets with different levels of crude protein (CP). A total of 180 laying hens were subjected into nine dietary treatments with four cages of five birds each. Experimental treatments consisted of three levels of CP (85.0, 92.5 and 100% of Hy‐Line W36 manual recommendation) and three levels of sanguinarine (0.00, 3.75 and 7.50 mg/kg) as a 3 × 3 factorial arrangement of laying hens which fed during a 70‐day feeding trial. The in vitro study showed that sanguinarine exhibited sevenfold and threefold decreased antioxidant activities to inhibit 2‐2‐diphenyl‐1‐picric hydrazyl free radical as well as ferric ion reducing rather than butylated hydroxyl toluene. Although using the decremental levels of CP caused the increase in heterophil‐to‐lymphocyte ratio (p < 0.01), dietary administration of sanguinarine could suppress the serum cholesterol and malondialdehyde concentrations as well as heterophil‐to‐lymphocyte ratio (p < 0.05). Additionally, decreasing CP content resulted in the decreased percentage of albumin (p < 0.05); however, it had no negative effects on humoral immunity. Nonetheless, feeding of at least 3.75 mg/kg sanguinarine led to the remarkable increases in serum gamma globulin concentration (p < 0.01) and secondary (p < 0.05) antibody titres against sheep red blood cells. Moreover, a decline in dietary CP content led to higher villi height and crypt depth (p < 0.05; p < 0.001) and consequently decreased villi height‐to‐crypt depth ratio (p < 0.001) than the optimum level (100% CP). In spite of the effects of sanguinarine on the suppression of Escherichia coli and Salmonella counts (p < 0.05), it markedly enhanced villi height‐to‐crypt depth ratio as well as lamina propria lymphatic follicles extent, simultaneously (p < 0.001). Therefore, in spite of the detrimental effects of feeding low‐CP diets on lymphocytes and serum albumin percentages, and villi height‐to‐crypt depth ratio, the administration of incremental levels of sanguinarine could improve cellular and humoral immunity, decrease ileal microbial counts and in turn improve the intestinal health indices in laying hens. 相似文献
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Autochthonous Chagas disease in the southern United States: A case report of suspected residential and military exposures 下载免费PDF全文
N. Harris L. Woc‐Colburn S. M. Gunter R. Gorchakov K. O. Murray S. Rossmann M. N. Garcia 《Zoonoses and public health》2017,64(6):491-493
Chagas disease is a parasitic infection that can result in a progressive dilated cardiomyopathy. Here, we present the epidemiologic details of a suspected locally acquired transmission case originating from the southern United States. This is the first published report of Chagas disease in a young, healthy United States veteran with repeat triatomine exposures in Arizona. Military personnel and Arizona residents should be aware of their Chagas disease transmission risks. 相似文献
78.
Martine Mialot Daniela Prata Anne Girard‐Luc Farasoa Rakotovao Jean‐François Cuveillier Florence Bernex 《Veterinary dermatology》2011,22(1):100-103
A 2.5‐year‐old ovariectomized female ferret developed multiple progressive linear and raised nodules on the skin. The first lesions occurred on the tail, which was then amputated. Over the following 3 years, additional lesions appeared in the vicinity of the scar and then further rostrally on the flanks and thorax. Histological and immunohistochemical investigation led to a diagnosis of multiple piloleiomyomas. The unique characteristics of this ferret disease are described and compared with those of multiple piloleiomyomas in humans and with those of other cutaneous smooth muscle cell tumours reported in the veterinary literature. 相似文献
79.
Ken Katsuda Mariko Kohmoto Kenji Kawashima Hiroshi Tsunemitsu 《Journal of veterinary diagnostic investigation》2006,18(4):350-354
Fecal samples from suckling (n=153) and weaned (n=116) piglets with diarrhea in Japan were examined for shedding of viral, bacterial, and parasitic pathogens using culture, microscopic, and polymerase chain reaction methods. In suckling piglets, diarrhea was attributed to infection with a single etiologic agent in 60.8% of cases and with combinations of agents in 22.2%. In weaned piglets, diarrhea was attributed to a single etiologic agent in 43.1% and to combinations of agents in 47.4% of cases. Rotavirus was the most prevalent agent in suckling (67.3%) and weaned (65.5%) piglets. The detection of other pathogens was associated with age of the animals examined. Coccidia were predominantly isolated from suckling piglets, whereas Escherichia coli was found predominantly in weaned piglets. Although a relationship was not observed between detection rate of rotavirus and age of piglets, a single group of rotavirus was detected in 87.5% of suckling piglets whereas multiple groups were detected in 51.6% of weaned piglets. The results of this study confirm that diarrhea in piglets can, to a variable degree, be causally associated with multiple agents. Additionally, these results suggest reasons why this syndrome can be difficult to control. 相似文献
80.
Distribution of Galanin and Galanin Receptor 2 in the Pre‐optic Area of the Female Guinea Pig 下载免费PDF全文
B. Hermanowicz K. Bogus‐Nowakowska M. Równiak W. Żakowski B. Wasilewska J. Najdzion A. Robak 《Anatomia, histologia, embryologia》2015,44(4):308-316
This study describes the distribution of galanin (Gal) and galanin receptor 2 (GalR2) in the pre‐optic area (POA) of the female guinea pig. Frozen sections were undergone for a routine immunofluorescence labelling. Gal and GalR2 display immunoreactivity in all parts of the pre‐optic area. Gal shows reactivity both in perikarya and fibres, whereas GalR2 was observed only in perikarya. Gal‐ and GalR2‐immunoreactive (‐ir) perikarya were the most numerous in the medial pre‐optic area (MPA) with the highest reactivity in its dorsal part. In the median pre‐optic nucleus (MPN) and periventricular pre‐optic nucleus (PPN), only single Gal‐ and GalR2‐ir neurons were observed. The highest density of Gal‐ir fibres was revealed in the PPN and the lowest in the lateral pre‐optic area (LPA). The results of this study indicate that the distribution pattern of Gal containing neurons overlaps well with the distribution pattern of GalR2‐positive neurons, especially in the MPA. This may suggest GalR2‐dependent activity in this brain region. 相似文献