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21.
G.A. Schad M. Kelly D.A. Leiby K. Blumrick C. Duffy K.D. Murrell 《Preventive veterinary medicine》1985,3(4):391-399
Digests of diaphragms from 33 482 hogs slaughtered in the mid-atlantic states were examined for the presence of Trichinella spiralis larvae. The samples were obtained from 7 slaughterhouses, ranging in slaughter capacity from less than 50 per day to more than 4000 per day. The sources of the hogs varied from “backyard” operations, raising hogs for home use, to commercial farms. The means by which hogs were brought to the slaughterhouse also differed; the larger slaughterhouses often purchased directly from the producer while the smaller slaughterhouses (1000 hogs per day or less) usually purchased through dealers or brokers. Infected hogs were detected more frequently than was expected from previously-published prevalence studies; overall, 0.58% of samples examined contained T. spiralis larvae. All of the infected hogs were marketed through the smaller slaughterhouses (less than 1000 per day) and nearly all were marketed through brokers. The mean number of larvae per gram of diaphragm, determined by slaugterhouses type, ranged from 0.5 to 74.6; most infections were light although 5 had counts of 1000–2480.Most of the positive samples were obtained from one slaughterhouse, the data from which exhibited marked differences in the frequency of infection by day of the week; 128 positive samples of the total of 190 found were obtained on Fridays, although only 10% of all samples were obtained on that day. Analysis of the geographic origin of shipments containing infected hogs revealed that most originated in New Jersey and Pennsylvania, although the hogs shipped from the latter state might originated in New England or Maryland. Attempts to trace back infected hogs for further epidemiological investigation were largely futile, owing to the absence of an identification system. 相似文献
22.
简要阐述黄竹的林学特性及三大效益,分析黄竹生产的现状和形势,提出在“四旁(”宅旁、村旁、路旁、水旁)发展黄竹生产的技术措施与对策。 相似文献
23.
我国橡实资源的开发利用 总被引:2,自引:0,他引:2
我国橡实资源非常丰富 ,有 7属 3 0 0多种 ,分布广泛 .据统计 ,我国约有橡实林 1.3 3× 10 7~ 1.67× 10 7hm2 ,年产橡实 60~ 70亿 kg.橡实营养丰富 ,橡仁含淀粉 5 0 %~ 70 %、可溶性糖 2 %~ 8%、单宁 0 .2 6%~ 17.74%、蛋白质 1.17%~ 8.72 %、油脂1.0 4%~ 6.86%、粗纤维 1.13 %~ 5 .89%、灰分 1.3 0 %~ 3 .40 % ;橡壳也含有大量的色素和单宁等成分 .橡实全身是宝 ,其开发利用的前景十分广阔 .对橡仁、橡壳进行综合利用 ,可以生产出淀粉、色素及一系列副产品 ,利用率将近 10 0 % ,几乎不产生任何污染 .同时还可以将橡实淀粉加工成变性淀粉等系列产品 ,从而提高产品的科技含量和经济价值 .我国橡实资源的开发利用不容乐观 ,存在资源破坏严重等系列问题 .为此 ,提出了旨在充分发挥资源优势、扩大利用规模、提高经济效益的开发利用的对策 . 相似文献
24.
2014年冬季,在如东县组织进行了皓月×菁松蚕品种全龄人工饲料育农村养蚕试验,生产的鲜茧上车率为75.91%,粒茧丝长为926.9m,解舒率仅45.28%,茧丝纤度为1.891D,光折为319kg。通过加强饲育管理和簇中管理,好蛹率上升,茧层含水率、公斤茧用料量有所下降。 相似文献
25.
The effects of feeding three local feeds (53%, 43% and 33% protein) on the growth and quality of the common carp (Cyprinus carpio L.) were investigated. The 43% protein feed proved most economical, with the highest biological value and has increased the protein and amino acid contents of the flesh but resulted in poor fish growth (0.10 g/day). 相似文献
26.
《Journal of Crop Improvement》2013,27(1-2):227-260
Abstract Pigeonpea (Cajanus cajan [L.] Millsp.), known by several vernacular and trade names such as red gram, tuar, Angola pea, Congo pea, yellow dhal and oil dhal, is one of the major grain legume crops of the tropics and sub-tropics. It is a favorite crop of small holder dryland farmers because it can grow well under subsistence level of agriculture and provides nutritive food, fodder, and fuel wood. It also improves soil by fixing atmospheric nitrogen. India by far is the largest pigeonpea producer where it is consumed as decorticated split peas, popularly called as ‘dhal’ In other countries, its consumption as whole dry seed and green vegetable is popular. Its foliage is used as fodder and milling by-products form an excellent feed for domestic animals. Pigeonpea seeds contain about 20-22% protein and appreciable amounts of essential amino acids and minerals. Dehulling and boiling treatments of seeds get rid of the most antinutritional factors such as tannins and enzyme inhibitors. Seed storage causes considerable losses in the quality of this legume. The seed protein of pigeonpea has been successfully enhanced by breeding from 20-22% to 28-30%. Such lines also agronomically performed well and have acceptable seed size and color. The high-protein lines were found nutritionally superior to the cultivars because they would provide more quantities of utilizable protein and sulfur-containing amino acids. 相似文献
27.
Variation for grain milling energy in Hordeum vulgare is associated with differences in grain size, shape and composition. Genetic polymorphisms within and between populations were found across the ecogeographical range of Hordeum spontaneum in Israel. Low milling energy estimates were positively correlated with and predictable by the aridity index. Milling energy in H. spontaneum, collected in Israel, ranged from the lowest values seen in making barley to twice the highest values seen in feed cultivars. It is concluded that H. spontaneum elite genotypes could be effectively identified by milling energy for use in the breeding of new cultivars. 相似文献
28.
哈尔滨交通干道两侧土壤重金属潜在生态危害评价 总被引:2,自引:0,他引:2
以哈尔滨市公滨路、香成路、哈-腰堡路3条交通干道两侧的土壤为主要研究对象,用原子吸收光谱法分析土壤中重金属Cu、Cd、Pb、Zn、Cr、Ni含量,采用松嫩平原土壤重金属背景值作为参比值,应用地质累积指数法和潜在生态危害评价法对重金属污染进行评价,以研究公路交通引起的土壤中重金属污染以及潜在的生态危害。结果表明:研究区土壤中Cu、Cd、Pb、Zn、Cr、Ni的含量显著高于背景值。Cd和Pb为中等污染,土壤对重金属元素的污染程度:ZnPbCdCrNiCu。污染源主要为机动车燃料、轮胎、机械中所含微量重金属成分。 相似文献
29.
陈振光 《福建农林大学学报(自然科学版)》1999,28(3)
中国水仙(NarcissitazettaL.var.chinensisRoem)是驰名中外的传统出口花卉.但水仙栽培周期长,种植3年才能提供商品花球;供花期短,一般集中在春节前后几周.其生长发育喜欢阴凉潮湿环境,不能在夏季炎热的气候条件下生长与开花.水仙开花期短,不适应现代花卉市场的要求,因而制约了水仙花生产的发展.作者于1989~1995年经过6年试验,对水仙的生长发育及其促成栽培技术进行系统研究,改进种植制度,革新栽培技术,探讨缩短水仙花球生长发育周期;深入系统研究水仙花芽分化的生理生化机制… 相似文献
30.
SISUNA-140全道路车加装灭火装置的研制 总被引:5,自引:2,他引:3
通过对我国引进的SISUNA 140全道路车进行技术改造,使之更加适合我国东北林区森林消防的需要.整套灭火装置由水箱、管路系统、水泵几大部分组成,在不破坏原车结构、不改变原车行驶性能的前提下,加装灭火装置,可组成一台森林消防车;卸下灭火装置,又可恢复原车的功能.灭火装置结构合理,装拆方便快捷,灭火效率高,具有推广应用价值. 相似文献