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西蜂在经历了长达 40余年的蜂螨危害之后 ,时至今日 ,它仍然没有离开人们的保护。假如今天人们不再去保护它 ,这个物种是否要从地球上灭绝掉呢 ?从西蜂的引进 ,到中蜂生存空间一直在缩小 ,说明西蜂是适宜在我国生存的。但面对大小蜂螨 ,西蜂似乎束手无策 ,而中蜂则表现得异常适应。中蜂有抗螨性能 ,西蜂有没有抗螨性能呢 ?从查阅的资料看 ,一些学者认为 ,中蜂是蜂螨的原始寄主。从这一观点看 ,西蜂是后来受害者。但这种观点遇到解释上的困难。因为西蜂早从 2 0年代就引进我国 ,而大小蜂螨则是从60年代才开始危害西蜂。那么 ,在 2 0年代— 60… 相似文献
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抗螨蜜蜂研究进展 总被引:1,自引:0,他引:1
《美国蜜蜂杂志》1 998年第 1 1期报道了E .H .埃里克森等在抗螨蜜蜂培育方面所取得的进展。研究表明 ,从各蜂场中找出抗螨蜂群 ,在不采取其它控制蜂螨措施的情况下 ,对这些蜂群进行繁殖 ,并维持其抗螨特性 ,是比较容易实现的。这项研究已得到一些养蜂者的实践证明。该杂志 1 999年第 1 2期又报道了埃里克森等在抗螨蜜蜂培育方面的最新进展。在他们研究的65群抗螨蜂群中 ,既有欧洲蜂 ,也有非洲蜂 ,还有它们的杂交种。结果并未发现非洲化蜜蜂的抗螨性强于欧洲蜜蜂。自 1 994年 1 1月以来 ,他们通过选择育种、隔离交尾和常规的饲养方法 ,不… 相似文献
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蜂胶的抗螨作用研究 总被引:2,自引:0,他引:2
为了避免蜂群受到蜂螨的为害 ,养蜂者通常采用杀螨剂来防治蜂螨 ,但使用杀螨剂有很多缺点。其中最大的问题 :一是造成蜂产品中药物的残留 ;二是蜂螨产生抗药性。所以 ,如何避免杀螨剂对蜂产品的污染以及降低蜂螨的抗药性 ,是蜂螨防治和杀螨剂筛选中必须重点考虑的问题。近年来 ,人们试图从天然产物的提取物中筛选抗螨药物。其中 ,有一种天然产物引起了科研人员的兴趣和重视 ,这种产物就是蜂产品中的重要成员———蜂胶。德国柏林大学动物研究所的GaredewA等科研人员研究了蜂胶对一种大蜂螨 (Varroadestructor)的作用 ,结果发现蜂胶对大蜂… 相似文献
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健蜂抗螨香粉防治蜂螨的联合试验 总被引:1,自引:0,他引:1
“健蜂抗螨香粉”是以中兽医、中医理论为指导 ,结合植物药学、民间“土农药”验方研制而成的。现将试验结果汇总报告如下 :1 试验材料供试蜂群 :甘肃省养蜂研究所定点试验蜂场及甘肃宁县、陕西绥德县、宁夏固原县、青海西宁市等地养蜂重点户的蜂群 ,蜂种为意大利蜜蜂。试验蜂药 :健蜂抗螨香粉 ,由甘肃省养蜂研究所蜂药厂提供。试验地点 :甘肃省天水市北道区、甘肃省宁县中村乡、陕西绥德县城关、宁夏固原县黑城镇、青海省西宁市。2 试验方法2 1 用药群的设立试验在甘肃省养蜂研究所定点试验蜂场进行 ,选取群势相似、蜂螨寄生率较高的蜂… 相似文献
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Chauhan KK Rout PK Singh PK Mandal A Singh SK Roy R 《Tropical animal health and production》2003,35(5):397-408
An investigation was made in 252 Barbari and Jamunapari kids to assess their resistance to natural infection with gastrointestinal (GI) nematodes and to establish indicator traits for such resistance in Indian goats. The indicator traits, faecal egg counts (FEC) and packed cell volume (PCV) were affected by various genetic and non-genetic factors. There were no breed differences in the FEC or PCV at 3, 6 or 9 months of age. Jamunapari male kids had a higher FEC than the female kids at 6 months of age. However, Barbari female kids had a higher FEC than the respective male kids at 9 months of age. At 6 months of age in both breeds, the kids born in the spring (March–April) had a higher FEC than those born in the autumn (October–November). The FEC of kids at 9 months of age was higher than at 3 or 6 months of age. Sire had a significant effect on PCV at 6 and 9 months of age. The kids born in the autumn had a higher PCV than those born in the spring. The PCV of male Barbari kids differed significantly from that of female kids at all the ages. The correlation coefficient of FEC on both body weight and body weight gain was negative, and there was a loss of body weight in the individuals with a high FEC. 相似文献
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Mites are frequent agents of skin diseases in veterinary dermatology, particularly in rodents. The authors report an original case of infestation in two guinea pigs of the same household. Two adult guinea pigs were presented with a 3‐month history of alopecia, matted hair, erythema, scales and mild pruritus. The first guinea pig showed almost complete truncal alopecia with mild scaling, whereas the other one had only recently developed mild alopecia of the abdomen and mild pruritus. Numerous live, long‐legged mites were present both in adhesive tape and skin scrapings. Mycology (Wood's lamp and DTM agar culture) was negative. Histopathological examination of a skin biopsy did not reveal any significant inflammatory disease and morphological changes were limited to hair follicles in the telogen phase. Mites were identified as hypopodes of Acarus farris (Acaridae), but no adult stages were present. Hypopodes were also found in the hay. Control was obtained with acaricidal treatment with Phoxim 0.05% once weekly for 4 weeks, and the elimination of contaminated hay. The lesions and the alopecia resolved rapidly. Hypopodes are additional nymphal stages of some mites of the suborder Astigmata. They develop for dispersing or dormancy under disadvantageous conditions. They can be active or inert, and some can be phoretic on the skin surface or intrafollicular. Although nonparasitic, they may cause dermatitis. Acarus farris have been rarely mentioned in the literature as a cause of dermatitis. This condition could be underdiagnosed or misdiagnosed in veterinary dermatology. Funding: Self‐funded. 相似文献
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YC Marquez CS Galina N Moreno H Ruiz A Ruiz H Merchant 《Reproduction in domestic animals》2005,40(6):553-558
In order to optimize the production of embryos under tropical conditions and to test a possible seasonal effect on embryo quality, 40 Zebu cows were superovulated during the dry season (April to May) and during the rainy season (July to August). A total of 116 (average 2.7/cow) and 83 embryos (3.5 average/cow) were obtained during the respective seasons. After classification as good, fair or poor quality, embryos were tested based on their ultrastructural differences (n = 53 dry season 16 good, 20 fair and 17 poor and n = 61 rainy season 21 good, 20 fair and 20 poor) and their degree of apoptosis using the TUNEL technique (n = 30 during the dry season and n = 55 in the rainy season). Structural characteristics determining embryo quality varied between good and fair quality embryos. No difference, however, was observed between good, fair and poor quality embryos from the two seasons. The number of TUNEL-positive cells was different among embryos (p < 0.001), being lower in labelled cells of good quality embryos regardless of the season. Fewer apoptotic cells were observed in embryos assigned in all three quality levels during the rainy season (p < 0.001). Ultrastructural evaluations confirmed the results obtained by TUNEL. Cryopreserved embryos of good (n = 25 in each season) and fair quality (n = 11 dry season; n = 17 rainy season) showed a significant decrease of TUNEL-positive cells during the rainy season (p < 0.05). Results suggest that embryos collected in the dry season have more cellular damage in contrast; embryos cryopreserved in the rainy season appeared morphologically better equipped to result in a pregnancy following transfer. 相似文献