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121.
本试验旨在建立玉米赤霉烯酮(ZEN)降解酶基因ZEN-jjm在枯草芽孢杆菌中的表达体系,确定其产物的生物降解活性及对母猪繁殖性能的作用。克隆ZEN-jjm基因,经EcoRⅠ和NotⅠ双酶切后连接至p HT01表达载体中,构建重组质粒;转化枯草芽孢杆菌,通过十二烷基硫酸钠聚丙烯酰胺凝胶电泳(SDS-PAGE)分析ZEN-jjm蛋白表达水平。高效液相色谱法(HPLC)检测表达的ZEN-jjm蛋白降解ZEN的活性。通过对母猪的繁殖性能的评价,确定ZEN降解酶降解ZEN对母猪繁殖性能的影响。双酶切和测序结果表明:ZEN-jjm成功插入p HT01中,SDSPAGE表明获得1株高效表达目的蛋白的重组枯草芽孢杆菌,其大小约为29 ku。HPLC结果表明表达的ZEN-jjm蛋白能有效地降解ZEN;表达的ZEN-jjm蛋白能显著缓解ZEN对繁殖母猪的毒害作用(P0.05)。综上:1)本研究成功构建了表达ZEN-jjm在枯草芽孢杆菌中的表达载体,并在枯草芽孢杆菌中得到了表达。2)表达的ZEN-jjm蛋白具有降解ZEN的生物活性。3)在饲粮中添加ZEN-jjm蛋白能显著降低ZEN对母猪能繁殖性能的危害。  相似文献   
122.
This article suggests a method for detecting oestrus, lameness and other health disorders for group housed sows fed by electronic sow feeders (ESF). The detection method is based on the measure of the individual eating rank, modeled using a univariate dynamic linear model. Differences between the predicted values of the model and the observations are monitored using a control chart: a V-mask is applied on the cumulative sum of the standardized forecast errors of the model. According to the respective V-mask parameters, alarms are given for each of the three states (oestrus, lameness, others) when the deviations between model predicted values and observations exceed some defined parameters. External information is incorporated into the model to limit the number of false alarms when a subgroup of sows enters and exits a group or both. The detection method was implemented on data collected within three production herds over 12 months. Visual recordings were performed to identify sows in oestrus or with health disorders. The detection method showed a high specificity. For oestrus detection, there was a sensitivity of 59%, 70% and 75% for the three herds as compared to 9% (herd 1) and 20% (herd 2) using lists of sows as alarms. Monitoring lameness results in a sensitivity of 56%, 70% and 41%, vs. 39%, 32% and 22% using the lists; monitoring other health disorders resulted in a sensitivity of 0%, 75% and 39% for the three respective herds, vs. 34% and 16% for herds 2 and 3 using the lists. To limit the number of false alarms, it is suggested to expand the model by including daily feed intake or body activity as other response variables.  相似文献   
123.
The objective of the study were to investigate the effects of low protein diets supplemented with amino acids on the reproductive performance,change of backfat thickness and milk composition of the lactating sows.35 crossbred sows with similar parity,body weight and body conditions were selected and randomly divided into 3 treatments and each treatment had 13,11 and 11 sows,respectively.A single-factor experimental design was used.Pigs in control group were fed conventional commercial diet with CP level of 17.7%,and the pigs in experimental groupⅠand Ⅱ were fed the diets supplemented with amino acids,and their CP level were 15.7% and 13.7%.The amino acid concentrations were the same in all three diets.The lactation length was 21 days.The results showed that:①Compared with control group,the total litter weight at 21 days,feed intake of lactating sows,survival rate and feed intake of piglets in the experimental groups had no significant difference(P>0.05).With the decrease of protein level,sows' body weight loss increased,but the differences were not significant among the treatments(P>0.05).②With the decrease of protein level,the ratio of sows' reduced fat thickness declined,but the differences among the treatments were not significant(P>0.05).③The milk composition of sows in experimental group Ⅱ was better than that in the control group,but the difference was not significant(P>0.05).The results indicated that using the diets with reduced CP level(from 17.7% to 15.7% or 13.7%)and supplemented with amino acids did not affect the performance of sows and piglets,and it would be an effective measure saving protein resource.  相似文献   
124.
为了对福建宁德某规模化猪场伪狂犬病免疫程序进行调整,应用ELISA法对待配后备母猪、繁殖母猪(怀孕40d母猪、怀孕70d母猪和哺乳母猪)、公猪以及60日龄、90日龄、120日龄和160日龄商品猪血清同时进行猪伪狂犬病gE和gB抗体检测,以掌握不同阶段猪伪狂犬病野毒的感染情况并制定适合本场的猪伪狂犬病免疫程序。免疫程序调整以后的检测结果显示:通过对不同猪群伪狂犬病疫苗程序的调整,商品猪后期和待配后备母猪伪狂犬病野毒感染为阴性,说明目前场内采用实验室检测调整伪狂犬病免疫程序的方法是科学的。  相似文献   
125.
Sow longevity is a key component for efficient and profitable pig farming; however, approximately 50% of sows are removed annually from a breeding herd. There is no consensus in the scientific literature regarding a definition for sow longevity; however, it has been suggested that it can be measured using several methods such as stayability and economic indicators such as lifetime piglets produced. Sow longevity can be improved by genetic selection; however, it is rarely included in genetic evaluations. One reason is elongated time intervals required to collect complete lifetime data. The effect of genetic parameter estimation software in handling incomplete data (censoring) and possible early indicator traits were evaluated analysing a 30% censored data set (12 725 pedigreed Landrace × Large White sows that included approximately 30% censored data) with DMU6, THRGIBBS1F90 and GIBBS2CEN. Heritability estimates were low for all the traits evaluated. The results show that the binary stayability traits benefited from being analysed with a threshold model compared to analysing with a linear model. Sires were ranked very similarly regardless if the program handled censoring when all available data were included. Accumulated born alive and stayability were good indicators for lifetime born alive traits. Number of piglets born alive within each parity could be used as an early indicator trait for sow longevity.  相似文献   
126.
为了研究抗菌肽制剂对妊娠母猪蓝耳病抗体水平及生产性能的影响,根据品种相同、体重相当的原则,随机选取180头妊娠母猪,试验A组、B组以及对照组各60头,试验A、B组饲料中添加0.3%、0.5%抗菌肽,对照组饲料中添加抗生素。通过ELISA抗体检测方法 ,分别检测试验组和对照组的蓝耳病抗体水平。结果表明:试验A、B组的蓝耳病抗体水平(S/P值)的稳定比例分别为80%和88.3%,显著高于对照组的68.33%(P≤0.05);试验A、B组的死胎率、窝均木乃伊数和死胎数均显著低于对照组(P≤0.05),窝均健仔数显著高于对照组(P≤0.05)。  相似文献   
127.
李永辉 《猪业科学》2021,38(9):42-47
在经济全球化和贸易一体化的前提下,全球各行各业都在以大数据为基础进行创新提高生产力,并将人工智能技术应用于人类生活生产的方方面面。国内许多生猪养殖企业也在生猪生产各环节中,不断采用智能化技术来提高养猪管理和生产效率。文章介绍了猪场的智能饲喂概念及生产工艺,并对应用效果和前景进行了阐述和分析。  相似文献   
128.
Automatic monitoring of animal behavior in livestock production opens up possibilities for on-line monitoring of, among others, oestrus, health disorders, and animal welfare in general. The aim of this study is to use time series of acceleration measurements in order to automatically classify activity types performed by group-housed sows. Extracts of series collected for 11 sows are associated with 5 activity types: feeding (FE), rooting (RO), walking (WA), lying sternally (LS) and lying laterally (LL). A total of 24 h of three-dimensional series is used. One univariate model and four multivariate models are used to describe all five activity types. Three multivariate models differ in their variance/covariance structure; a fourth alternative multivariate model (MU) simply combines the 3-axes of the univariate model, assuming independence. For each model, the activity-specific parameters are estimated using the EM algorithm. The classification method, based on a Multi-Process Kalman Filter provides posterior probabilities for each of the 5 activities, for a given series. For the univariate model, LL is the activity which is best recognized by the 3-axes; FE, RO and WA are best recognized by one particular axis; LS is poorest recognized. The average results are improved by using all four types of multivariate models. The percentages of activity recognition are similar among the multivariate models. By grouping the activity types into active (FE, RO, WA) vs. passive (LS, LL) categories, the method allows to correctly classify 96% of the active category and 94% of the passive category.  相似文献   
129.
母猪无乳综合征是养猪业比较常见的疾病之一,易给养猪业带来较大的经济损失。该文总结了母猪无乳综合征的发病原因、临床症状及其诊断与预防方法,最后提出母猪无乳综合征的预防措施。  相似文献   
130.
 于2009年10月8日至2010年1月20日,在云南邦格农业集团有限公司建水生猪养殖基地,选择48头初产长大二元杂种怀孕母猪,随机分为4组,第1组为对照组,2~4组为试验组,分别在日粮中添加0,3%,5%,10%的普罗宝酶解蛋白粉(EP - 45),研究EP - 45替代部分豆粕对妊娠母猪生产性能影响。结果表明:与对照组相比,5%与10%添加组的妊娠母猪背膘厚、产仔数和仔猪初生重均存在显著差异(P<0.05),且5%添加组的产活仔数也与对照组存在显著差异(P<0.05)。  相似文献   
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