首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   263篇
  免费   7篇
  国内免费   15篇
农学   4篇
基础科学   1篇
  5篇
综合类   42篇
畜牧兽医   233篇
  2022年   5篇
  2021年   10篇
  2020年   8篇
  2019年   12篇
  2018年   4篇
  2017年   13篇
  2016年   12篇
  2015年   12篇
  2014年   18篇
  2013年   23篇
  2012年   25篇
  2011年   26篇
  2010年   15篇
  2009年   10篇
  2008年   7篇
  2007年   17篇
  2006年   11篇
  2005年   3篇
  2004年   1篇
  2003年   5篇
  2002年   4篇
  2001年   3篇
  2000年   1篇
  1999年   1篇
  1997年   1篇
  1996年   2篇
  1995年   3篇
  1994年   1篇
  1993年   3篇
  1992年   5篇
  1991年   3篇
  1990年   3篇
  1989年   1篇
  1988年   2篇
  1986年   2篇
  1984年   1篇
  1980年   4篇
  1979年   1篇
  1978年   4篇
  1976年   1篇
  1975年   1篇
  1956年   1篇
排序方式: 共有285条查询结果,搜索用时 31 毫秒
191.
将30只处于乏情期的雌性水貂,随机分成6组.除一对照组外,5个实验组每只动物肌注PMSG 200 IU,在注射后2、3、4、5、6 d(5个阶段)分别取卵巢和子宫作组织切片,光镜下观察其结构变化.结果显示,注射PMSG后,乏情期母貂的卵巢迅速增长,卵泡发育加快,子宫也迅速增大,表明PMSG能促进之情期水貂雌性生殖系统迅速发育.  相似文献   
192.
Advanced lesions in the jejunal mucosa in virus enteritis of mink were studied by scanning electron microscopy. The changes were found to be in good accordance with those observed in the light microscope, and included ballooned degeneration of entero-cytes, epithelial desquamation, the occurrence of fibrinous pseudo-membranes, atrophy or total loss of villi; partially atrophied villi were frequently fused. In some areas there were incipient regenerative processes, including proliferation of ballooned cells which covered the luminal surface of the damaged jejunal wall.  相似文献   
193.
“金州黑色标准水貂”品种的生产性能   总被引:5,自引:4,他引:1  
“金州黑色标准水貂”是通过杂交培育成的水貂新品种。该品种水貂具有优良的生产性能 ,繁殖力高 ,仔貂生长发育快。适合北纬 35°以北地区饲养 ,综合经济指标已达到国际先进水平。  相似文献   
194.
A survey on perinatal mortality in young mink   总被引:1,自引:0,他引:1  
The incidence of perinatal mortality in mink was investigated in commercial farms in Argentina. Of a total of 2122 kits, 548 of those that were born alive died within the first four weeks of life (25.8% mortality) and there were also 62 stillborn kits. Death resulted from a variety of causes of which septicaemia, starvation and hypothermia were the most common conditions. The highest mortality occurred within the first week of life (61.9%). The lesions found in young kits at post-mortem examination are described and related to contributory factors such as weight, litter size and age at death.Dr Villar died on 26 September 1989  相似文献   
195.
在发生急性死亡的水貂脑中分离到9株细菌,经细菌培养、染色镜检、生化试验、动物试验证实分离菌株均为肺炎链球菌。药敏试验结果:分离菌株大部分对氟苯尼考、阿米卡星、头孢噻肟、氨苄西林、呋喃妥因敏感,应用敏感抗菌素与疫苗紧急免疫的方式,对该病的综合防治措施做了一系列探索式研究,并取得了理想的防治效果。  相似文献   
196.
Summary

The present article (part I) reviews recent developments in animal spongiform encephalopathies (SEs), with the exception of bovine spongiform encephalopathy (BSE), which is dealt with in part II.

The article focuses on scrapie and describes epidemiological aspects and the prospects for a preclinical diagnosis. Up to now, confirmatory diagnosis of scrapie depended on histological examination of the brain, collected during post‐mortem examination from sheep with clinical signs of the disease. An altered protein, PrPSc, can be detected in the brain of diseased animals. The demonstration of the same protein in the spleen and in peripheral lymph nodes of infected animals seems to offer interesting possibilities of arriving at a method for a preclinical diagnosis, and thus a diagnosis in the live animal. Progress has also been made in our understanding of the relationship between the genetic constitution and susceptibility of the host. Susceptibility is expressed as the survival time of sheep inoculated with scrapie. This was thought to be determined by a single genetic locus designated the Sip gene (scrapie incubation period gene). Putative markers for the two alleles of the Sip gene, sA and pA, have been discovered, consisting of restriction fragment length polymorphisms (RFLPs). In field tests, however, the link between these markers and the length of incubation time was far from consistent. These RFLPs were found to be situated outside the prion‐protein‐co‐ding region of the ovine gene. In later studies, RFLPs were detected inside this region. These markers appear to be more informative, i.e. they correspond with a difference in the length of the scrapie incubation period.

Finally, the article briefly describes recent developments in other, lesser known, animal spongiform encephalopathies: chronic wasting disease and other spongiform encephalopathies in exotic ungulates, transmissible mink encephalopathy, and feline spongiform encephalopathy, focusing on their possible links with scrapie or bovine spongiform encephalopathy.  相似文献   
197.
Abstract

A total of 730 dark mink, half of each sex, representing 94 paternal progeny groups originating from 16 farms were housed on a test station from about 10 weeks of age until pelting. Average daily feed consumption in paternal progeny groups was registered daily. Individual body weights were recorded five times. Feed consumption, feed efficiency and weight gain in paternal progeny groups were calculated in four subperiods corresponding to the times of weighing. These traits, body weights and length of pelts were analysed for differences between paternal progeny groups and farms of origin. A considerable difference between farms of origin and paternal progeny groups was found for most traits, indicating genetic variation. Correlations between averages of paternal progeny groups were calculated, and interpreted as approximations to genetic correlations. Feed consumption was highly correlated across periods. Feed efficiency showed low to medium correlations between periods. A favourable correlation was found between efficiency of weight gain and efficiency of longitudinal growth.  相似文献   
198.
Abstract

The effect of cage size and nest box environment on circadian rhythm and on stereotyped and non-stereotyped activities was measured for 66 farmed female mink fed ad libitum. The behaviour of the animals was recorded over 24 h on video in the months of September and October. Weight and feed consumption were measured for the 66 females and the 66 male mink placed with the females. The experiment included three cage sizes (0.10, 0.27 and 1.10 m2) and cages with and without nest boxes. In the cages with nest boxes the use of wire netting cylinders and shelves was evaluated.

Farm mink, fed ad libitum, had their primary activity period from 04:00 to 10:00 h. There was no food anticipatory activity, but the actual feeding at noon caused an interruption of the animals' resting period. Mink in cages without nest boxes performed more stereotyped behaviour than mink with nest boxes. There was no effect of cage size on the measured behavioural elements. Mink were passive for more than 70% of the day and night and preferred to rest together. Apart from resting in the nest box, mink preferred to rest on shelves above floor level. Lacking the possibility of using a nest box and performance of stereotyped behaviour increase the feed intake of farm mink. A large variation between animals, having a significant effect on all the measured behavioural elements, indicates different coping patterns and/or stress sensitivity.  相似文献   
199.
猫细小病毒、犬细小病毒、貂细小病毒的特征比较   总被引:2,自引:1,他引:1  
猫细小病毒、犬细小病毒和貂细小病毒是3种极为相似的细小病毒。最初人们主要根据患病水貂、猫、犬临床症状相似的特点,注意到它们之间可能有密切关系。时至今日,对这3种病毒的许多方面都已进行了深入的研究。作者从猫细小病毒、犬细小病毒、貂细小病毒病共同特性、生物学差异和进化机制等方面对这3种病毒的特征进行了比较和综述。  相似文献   
200.
不同锌水平对水貂生产性能及营养物质消化率的影响   总被引:2,自引:0,他引:2  
研究不同锌水平对水貂生产性能及营养物质消化率的影响。结果表明:日粮中添加不同水平的锌有降低水貂干物质、有机物质、蛋白质和脂肪采食量的趋势;锌水平为30mg/kg时显著降低微量元素的排出量,减少微量元素对环境的污染。添加不同锌水平的锌显著提高生长期水貂的日增重。在日粮中添加ZnSO4·7H2O水平为30mg/kg时水貂日增重效果最好。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号