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51.
阅读提示:"6.26"国际禁毒日前后,媒体有关缉毒犬的报道让读者领略了这一神秘武器的风采。不少读者向本刊反映,很想进一步了解中国缉毒犬训练使用的幕后故事,为飨读者,本刊专门采写了下文。  相似文献   
52.
采取猪血清68份、鸡血清71份,分别进行免疫抗体检测。结果合格率为:猪口蹄疫4.41%(3/68)、猪瘟70.59%(48/68);鸡新城疫87.32%(62/71)、高致病性禽流感76.06%(54/71)。  相似文献   
53.
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   
54.
松嫩羊草草原火烧后地上生产力的变化   总被引:3,自引:0,他引:3  
松嫩羊草草甸草原不同时间火烧后,对羊草种群地上初级生产力产生不同影响,伴随出现不同的次级生产力变化格局,早春火烧提高羊草种群地上生产力,8月份产量增14.6%,晚春火烧导致羊草种群地上生产力下降,8月份产量降低15.5%,与未烧相比差异显著,火烧后,叶茎比率提高,尤其是晚春火烧处理,叶茎比率最高,火烧后,蝗虫数量增多,但晚烧地7月份蝗虫数量多,早烧地8月份蝗虫数量多,未烧地基本保持稳定,三者之间差  相似文献   
55.
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   
56.
省力化养蚕技术及其应用   总被引:3,自引:0,他引:3  
降低生产成本,降低劳动强度,提高蚕桑生产比较效益,是当前和今后蚕桑生产稳定发展的重要问题,本文概要介绍我省省力养蚕技术的发展过程,提出了省力化养蚕技术规范,应用省力化养蚕技术的五条技术关键和推广措施以及应用效益。  相似文献   
57.
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   
58.
Chlamydia spp. are obligate intracellular gram-negative bacteria that cause a wide range of significant diseases in humans and animals worldwide, resulting in significant economic losses. Chlamydial infection in cattle has been reported in many countries including China. However, there has been no survey of chlamydial infection of dairy cattle in Guangzhou, southern China. The objective of the present investigation was to examine the chlamydial seroprevalence in dairy cattle in Guangzhou, subtropical southern China by using an indirect hemagglutination assay (IHA). The overall seroprevalence of chlamydial infection in dairy cattle was 7.25% (29/400). Greater than or equal to eight-yr-old dairy cattle had the highest seroprevalence (10.34%), followed by those that were ≥ 6 years old or < 7 years old dairy cattle (10.20%), although there were no statistically significant differences among different groups (P > 0.05). Dairy cattle with 5 pregnancies had the highest seroprevalence (10.81%). These results indicate that chlamydial infection was present in dairy cattle in Guangzhou, subtropical southern China, and integrated strategies and measures should be executed to control and prevent chlamydial infection and disease outbreak in the study region.  相似文献   
59.
为了解正安县山羊主要疫病的发展趋势,通过虎红平板凝集试验、正向间接血凝试验、酶联免疫吸附试验等方法对正安县引进山羊进行布鲁氏杆菌病、O型口蹄疫、AsiaI型口蹄疫、山羊传染性胸膜肺炎、山羊痘等主要疫病血清抗体的检测。结果表明,O型口蹄疫、AsiaI型口蹄疫和山羊痘免疫抗体阳性率分别为79.42%、81.18%和99.58%,未免疫的布鲁氏杆菌病、羊传染性胸膜肺炎的丝状支原体山羊亚种和绵羊肺炎支原体未免疫抗体阳性率分别为0%、0%和3.81%。监测结果为山羊健康的引进、培育和扩繁提供了一些基础数据,对指导养羊生产有一定的意义。  相似文献   
60.
通过在鱼苗培育过程中使用微生态营养素和传统养殖模式进行对比,分析测定养殖环境中的浮游生物种类、数量和生物量以及透明度等理化因子,研究微生态营养素在苗种培育中的使用效果。研究结果表明:微生态营养素能有效促进浮游生物的生长,施放微生态营养素的水体中鱼类喜食且易消化的浮游植物及浮游动物的种类和数量显著增加,总生物量提高了20%~58%,水体透明度降低了30%~52%,培育出来的苗种,较常规培育的个体更大、成活率更高。  相似文献   
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