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41.
42.
Mersha Chanie Tamiru Negash Asegedech Sirak 《Tropical animal health and production》2010,42(6):1103-1109
Ectoparasites are the major causes of skin lesions in animals. Clinical, skin scraping examination, and histopathological
studies were conducted to identify and characterize skin lesions in small ruminants caused by ectoparasites. Mange mites,
lice, sheep keds, and ticks were collected from the skin of affected animals for species identification. Skin biopsies were
collected from affected part of the skin and fixed in 10% neutral buffered formalin for histopathology. Of 1,000 sheep and
600 goats examined, 815 (81.50%) sheep and 327 (54.5%) goats were infested with one or more types of ectoparasites. Sarcoptes scabiei var ovis, Demodex ovis, Psoroptes ovis, Bovicola ovis, Melophagus ovinus, and Amblyomma variegatum and other tick species were identified from sheep. S. scabiei var caprae, Demodex caprae, Linognathus stenopsis, and A. variegatum and other tick species were identified from goats. Gross skin lesions or defects observed on the skin include stained and
ragged wool, loss of wool/hair, nodules, crusts, lichenification, and fissuring. Microscopic evaluation of H and E stained
skin sections revealed lesions in the epidermal layer such as hyperkeratosis, acanthosis, and melanin inconsistency on the
basal cells of the epidermis. Follicular keratosis, perifolliculitis, frunculosis, perivasculitis, and aggregates of inflammatory
cells (of acute and chronic type) with fibrosis were experiential in the dermal layer of the skin. Most of the skin lesions
caused by ectoparasites are overlapping. Thus, ectoparasites control program should be executed to reduce skin lesions as
skins are the major export commodity of the country. 相似文献
43.
Monde Mapekula Michael Chimonyo Cletos Mapiye Kennedy Dzama 《Tropical animal health and production》2010,42(7):1413-1419
Understanding the utilisation patterns of milk assists in designing appropriate dairy development schemes in rural communities.
The objective of the study was to determine milk utilisation patterns in different smallholder farming systems in the Eastern
Cape Province of South Africa. Data were collected through the administration of recording sheets to 130 randomly selected
households in Alice, Fort Beaufort and Queenstown districts. Amounts of milk produced per household ranged from 9 to 21 l
per household per day. Milk consumption/household/day was similar among the three districts. Milk consumption in the early
lactation doubled the amount consumed in late lactation (P < 0.05). Milk in the communal areas was largely utilised as fresh or sour milk. Fresh milk was mostly used in tea/coffee
or to make porridge for children. Sour milk was consumed with thick boiled maize meal. Fort Beaufort (10.2 ± 1.37 l/day) had
the highest sour milk sales whilst Queenstown had the highest fresh milk sales (9.7 ± 5.57 l/day). It was concluded that quantities
of milk consumed or sold as fresh or sour were generally low and varied across smallholder farming systems. 相似文献
44.
2021年,沂南县推进动物疫病强制免疫“先打后补”工作,依托“鲁牧云”信息平台,通过强化组织领导,加强政策宣贯,强化人员培训,放开强免疫苗经营渠道,提供抗体检测无偿服务等措施,提升了养殖场户“先打后补”的积极性、自主性、灵活性,强化了养殖场户动物防疫主体责任,满足了养殖场户疫苗多样化需求。但由于 “先打后补”补助金额少、社会化服务不规范、基层动物防疫体系弱化、缺少配套工作经费等原因,部分养殖场户实施“先打后补”的积极性不高。建议通过规范社会化服务组织,强化培训水平,提高补助标准,强化三级(县乡村)基础设施建设,升级“鲁牧云”等措施,确保“先打后补”政策惠及更多养殖场户。 相似文献
45.
产蛋下降综合征(EDS-76)病毒DNA探针的制备及应用研究 总被引:2,自引:0,他引:2
用纯化的产蛋下降综合征(EDS-76)病毒(H91毒株)悬液提取的核酸,经琼脂糖凝胶电泳只出现1条分子量较大、背景清晰的核酸带。用BamHI酶消化产生4个片段,大小分别为17kb、10kb、4.0kb和2.0kb。将其中的2.0kb片段克隆进pUC18DNA载体中,重组质粒DNA用digoxigenin标记作为DNA探针,在dotblot中该探针不与鹅胚尿囊液核酸抽提物、马立克氏病病毒(MDV)DNA、鸡传染性贫血病毒(CAV)DNA、SPF鸡基因组DNA等核酸反应,只与3株EDS病毒(EDS标准毒株AV-127、EDSH91毒株和从健康鹅体中分离的EDSY81毒株)DNA呈阳性反应。人工感染产蛋母鸡和雏鸡后24h即可用该探针从泄殖腔棉拭子样品中检测出EDS病毒DNA,在感染后35h仍能从部分感染鸡样品中检出。对部分探针检测阳性鸡的泄殖腔棉拭子样品用SPF鸡胚分离病毒,并用HA和HI试验检测分离病毒的特异性;在感染过程中,同时检测了血清中HI抗体的消长情况。结果表明,人工感染鸡排毒至少可以维持2个月左右,而且血清中HI抗体即使很高,也不能阻止感染鸡的排毒。 相似文献
46.
47.
哈尔滨地区犬旋毛虫对猪,犬的感染性研究 总被引:2,自引:1,他引:2
用消化法所得的犬旋毛虫蚴分别接种猪,犬。结果表明:犬旋毛虫对猪、犬的感染性存在着明显差异,在犬的繁殖力指数为18.68。而在猪为零,说明哈尔滨地区犬旋毛虫相当于本地毛形线虫。犬旋毛虫对犬易感而对猪不感染,通信能通过猪的感染而对人体健康构成威胁。 相似文献
48.
将新城疫病毒(NDV)F46E9株和LaSotaE4株的融合蛋白裂解位点(Fc)基因从本实验室构建的重组质粒pUCF46Fc和pUCLaFc中用EcoRI和SalⅠ切出。将这2个毒株的Fc基因定向克隆入昆虫杆状病毒表达载体pSXIVVI+X3的EcoRI和SalⅠ位点之间,获得2个毒株的Fc基因克隆pX3F46Fc和pX3LaFc。重组质粒用EcoRI/SalⅠ、PstⅠ酶切法、PCR和核酸探针法进行了鉴定,证明插入的基因来自pUCF46Fc和pU-CLaFc,插入的位置和方向都正确。这2个载体的构建为Fc基因在昆虫细胞系统的表达创造了条件。 相似文献
49.
不同来源硒对异育银鲫的生物学效应研究 总被引:1,自引:0,他引:1
以异育银鲫为试验动物,研究不同来源的硒(蛋氨酸硒和纳米硒)对其生长性能、肌肉生化组成和谷胱甘肽过氧化物酶活性的影响。试验分为3个处理,日粮中添加硒浓度分别为0 mg/kg(对照组)、0.5 mg/kg(蛋氨酸硒)和0.5 mg/kg(纳米硒),每个处理3个重复。结果显示,与对照组相比,蛋氨酸硒和纳米硒均可显著提高异育银鲫的末重、相对增重率以及谷胱甘肽过氧化物酶活性(P<0.05),但是蛋氨酸硒处理组和纳米硒处理组间差异不显著。纳米硒处理组肌肉中硒含量显著高于其他两组(P<0.05),蛋氨酸硒处理组肌肉中硒含量显著高于对照组(P<0.05)。研究表明,饵料中添加一定浓度的蛋氨酸硒和纳米硒具有一定的生物学效应。 相似文献
50.
S. Kennou Sebei R. Bergaoui M. Ben Hamouda R. G. Cooper 《Tropical animal health and production》2009,41(7):1427-1438
The aim of the current investigation was to determine wild ostrich reproductive behaviour in Orbata Nature Reserve by observing
16 hens and 28 cocks over a seven-year period. Intense laying commenced in January, one month after the cessation of the rainy
season, and 92% of the eggs were produced during the dry season (January to May, peaking in March). Over the seven years,
1,322 eggs were laid in 69 nests, which corresponded to an annual average production of 19.2 ± 9.1 eggs/nest and 11.8 eggs/hen.
24 nests (34.78%) were non-brooded, 17 nests (24.64%) were deserted in the course of incubation, and 28 nests (40.58%) possessed
hatched eggs. All the non-incubated nests had egg losses equivalent to 46.6 ± 12.6%. Hatchability success of incubated eggs
was 41.9 ± 12.0%. Ostriches tended to dig their nests adjacent to the reserve enclosure which had direct access by road and
track, the latter subjecting them to human disturbance and predation. The systematic obstruction of these nests stimulated
ostriches to build additional nests within the reserve perimeter. The authors discussed the results recorded in an ostrich
flock in relation to the environmental factors (climatic factors, food disponibility and predation) and suggested possibilities
for improved wildlife management. 相似文献