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51.
本文系统地阐述了紫花苜蓿灌溉的理论与技术,内容包括需水量、需水强度、入渗速率、灌溉需要量、灌溉定额、灌水深度、灌水定额、灌水周期、灌水次数、灌水时期、灌水强度、灌溉方法等内容。  相似文献   
52.
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   
53.
实践已证明,在犬群中只有约二十分之一的犬适宜作为缉毒犬,因为本身的自然素质及心理素质存在着一定的差异,犬的潜能也是有区别的.好的受训犬能节省训犬员训练时间,提高训练成功率及训犬员的信心,更好地为人民服务.  相似文献   
54.
寡糖(Oligosaccharides,Os)又称寡聚糖或低聚糖,是指2~10个单糖通过糖苷键连接形成的一类糖,是近年来开发的无公害饲料添加剂之一.由于具有无污染、无残留、功能奇特等优点,日益受到人们的重视,已成为当今研究的热点.在日本,食品和饲料中使用寡糖已成为常规 [1].其他各国饲料中寡糖的使用量也呈逐年上升的趋势.  相似文献   
55.
牛乳免疫球蛋白和补体含量测定   总被引:3,自引:0,他引:3  
用琼脂单项免疫扩散法测定牛乳免疫球蛋白和补体含量。结果表明:初乳免疫球蛋白和补体C3含量极显著高于常乳(P〈0.01);初乳补体C4含量显著高于常乳(P〈0.05);初乳中免疫球蛋白和补体含量于产后3天达到高峰。  相似文献   
56.
蚕蛹蛋白水解技术研究进展   总被引:6,自引:0,他引:6  
目前蚕业资源综合利用正作为一个新兴产业得到广泛关注。蚕蛹是缫丝过程中的副产物,富含蛋白质,含有人体需要的18种氨基酸,其中8种必需氨基酸含量达40%以上,其组成和比例非常符合WHO/FAO提出的氨基酸模式,是优质蛋白质及氨基酸来源。我国每年有10多万吨干蚕蛹可供利用,但大多被  相似文献   
57.
养中蜂最主要的目的是追求蜂蜜产量.目前国内有关中蜂技术较全面、系统的著作有杨冠煌老师的<中华蜜蜂>和龚凫羌先生的<中蜂饲养原理与方法>.但至今尚未见到有相当规模的示范蜂场的报道.我的技术措施在我地推广了20多年,现在已经在多个地区全面开花了. 今年春季的荔枝、龙眼花期,我县平均单脾产量为5~6.5千克,中蜂群产量在20~30千克,单脾平均产量为5.5~7千克.  相似文献   
58.
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   
59.
山羊鼻内腺瘤和腺癌的病理学研究   总被引:2,自引:1,他引:2  
发生于内蒙古自治区某地的山羊鼻内肿瘤呈地方性流行,临床上病羊初期流出大量浆液性鼻液,随后逐渐出现呼吸困难和鼻塞音,肿瘤可侵犯周围组织引起眼球突出和头颅变形,最后死于窒息。14例山羊鼻内肿瘤的病理学研究表明,肿瘤起源于筛骨迷路粘膜的腺体(包括浆液腺和粘液腺),组织学上为腺瘤,以后可转变为腺癌,并向周围组织作浸润性生长,未见转移。2例作透射电镜检查见瘤组织有异型性,瘤组织和瘤组织内未见病毒样颗粒。发生  相似文献   
60.
Information regarding the susceptibility of swine lymphocytes to PCV2 is rather limited. To further explore and characterize the PCV2 infection in swine lymphocytes, an in vitro model using concanavalin A (Con A)-stimulated peripheral blood lymphocytes (PBLs) obtained from clinically healthy PCV2-carrier pigs was introduced. It was found that the PCV2 antigen-containing rate was below 2% in PBLs from healthy PCV2-free pigs following treated simultaneously with Con A and PCV2. However, significantly higher PCV2 antigen- and nucleic acid-containing rates could be seen in Con A-stimulated PBLs from clinically healthy PCV2-carrier pigs. Prior to Con A treatment, both of the PCV2 antigen- and nucleic acid-containing rates in PBLs from healthy PCV2-carrier pigs were less than 1%; however, they reached 22.1+/-5.7% by flow cytometry and 27.1+/-6.5% by in situ hybridization, respectively, at 4-day post-incubation with Con A. Phenotyping of PCV2 antigen-containing cells revealed that PCV2-positive cells could be detected in both T and B lymphocyte populations within which IgM-positive B lymphocytes appeared to have a relatively higher positive rate. The Con A-stimulated PBLs also displayed a significantly higher viral load by the measurement of either PCV2 DNA copy number or viral titer when compared with the non-treated PBLs from healthy PCV2-carrier pigs. The results indicate that PBLs, especially IgM-bearing B lymphocytes, are indeed susceptible to PCV2 infection and PCV2 is capable of replicating in dividing lymphocytes. This activation-induced replication may explain in part the pathogenesis of lymphoid depletion in PMWS-affected pigs.  相似文献   
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