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571.
The purpose of this experiment was to study the effect of compound enzyme and compound enzyme bacteria preparation on the degradation rate of diet in vitro and milk production performance of dairy cows at different lactation stages.In in vitro experiment,the basic diet (group Ⅰ) and the basic diet added with compound enzyme (group Ⅱ) and compound enzyme probiotics preparation (group Ⅲ) were used as fermentation substrate respectively.After 72 h of culture in vitro,the dry matter degradation rate (DMD) and crude protein degradation rate (CPD) of the diet were measured at different time (6,12,24,36,48 and 72 h).In feeding experiment,24 dairy cows with similar body weight,parity and condition were divided into three groups at early lactation (30 d±5 d),middle lactation (100 d±5 d) and late lactation (250 d±5 d),respectively.The cows in control group (group Ⅰ) were fed with TMR,in compound enzyme group (group Ⅱ) and the compound enzyme probiotics group (group Ⅲ) were fed with the TMR added with 1 kg/t compound enzyme and compound enzyme probiotics respectively.The trial period was 74 days,including 14 days of pre trial period and 60 days of normal trial period.`The results showed that:①In vitro DMD and CPD of the two groups increased with the prolongation of treatment time.At each time point,the values of DMD and CPD in group Ⅲ were higher than those in group Ⅱ,the difference of DMD was significant at 6 and 72 h (P<0.05),CPD was significant at 36 and 72 h (P<0.05),and there was no significant difference at other time points (P>0.05).②In the early stage of lactation,the average daily milk production of groups Ⅱ and Ⅲ increased by 3.68% and 4.10% respectively compared with group Ⅰ,the difference was significant (P<0.05),and the difference between groups Ⅱ and Ⅲ was not significant (P>0.05).In mid-lactation,the average daily milk production of groups Ⅱ and Ⅲ increased by 7.53% and 10.66% respectively compared with group Ⅰ (P<0.05),and the difference between groups Ⅱ and Ⅲ was not significant (P>0.05).In the later stage,the average daily milk production of groups Ⅱ and Ⅲ increased by 7.06% and 5.16% respectively compared with group Ⅰ (P<0.05),and the difference between group Ⅱ and Ⅲ was not significant (P>0.05).In conclusion,both compound enzymes and compound enzyme probiotics preparations could improve the in vitro DMD and CPD of the diet and the milk production of dairy cows in different periods to a certain extent.Among them,the compound enzyme preparation had a better effect on increasing milk production of dairy cows in the late lactation,while the compound enzyme probiotics preparation has a better effect on increasing milk production in mid-lactating dairy cows.  相似文献   
572.
益生菌对动物肠道微生物生态学影响的研究进展   总被引:4,自引:2,他引:4  
益生菌是一种能够扶植正常微生物菌群,颉颃病原菌,把生态失衡调节为生态平衡的活的生物饲料添加剂。作者主要在益生菌对动物肠道微生态学的影响及其作用机制方面进行了综述。  相似文献   
573.
选用1日龄健康AA肉雏鸡1200羽,随机分成6个处理,每个处理8个重复,分别饲喂添加抗生素(杆菌肽锌16.7mg·kg-1和硫酸粘杆菌3.3mg·kg-1,对照组)、低聚木糖(0.02%)、合生素(0.005%益生菌+0.005%及0.01%低聚木糖)、抗生素与低聚木糖(对照组抗生素+0.005%及0.01%低聚木糖)6种不同日粮,研究不同处理对肉鸡肠道微生物菌群和生产性能的影响。结果表明:与对照组相比,各试验组肉鸡空肠的乳酸菌数分别提高了19.89%(P<0.05)、9.17%、20.21%(P<0.05)、13.98%(P<0.05)和16.75%(P<0.05),除0.005%低聚木糖+抗生素组,其它各组大肠杆菌数量均较高。各试验组前期(0~21日)、后期(22~42日)和全期(0~42日)的肉鸡体增重分别提高了0.8%~15.1%、2.9%~29.0%和2.2%~24.0%,后期和全期饲料转化率分别改善了2.5%、4.3%、10.4%、16.9%、12.5%和1.0%、3.3%、6.2%、7.1%、6.2%,以添加0.005%低聚木糖+抗生素组的肉鸡增重、饲料转化率与成活率为最佳。  相似文献   
574.
为了探究饲料中添加复合益生菌对中华鳖(Trionys sinensis)生长及血液生化指标的影响,在体重为(227.47±14.42)g 的中华鳖基础饲料中分别添加复合益生菌0 mg/kg(对照组Ⅰ)、500 mg/kg(试验组Ⅱ)、1000 mg/kg (试验组Ⅲ)和2000 mg/kg(试验组Ⅳ);试验共分4组,每组3个重复,在(30±2)℃温室中进行,投喂140 d。结果表明,各试验组均能显著提高中华鳖增重率、特定生长率和存活率(P <0.05),降低饵料系数(P <0.05),且Ⅲ组增重率、特定生长率和存活率最高,饵料系数最低,增重率比Ⅰ组提高了29.25%;各试验组均能显著提高中华鳖脂肪酶、淀粉酶和胰蛋白酶活力(P <0.05),当添加量为2000 mg/kg 时,淀粉酶活力有所下降(P <0.05);与对照组相比,各试验组均能显著降低血清中总胆固醇、尿素氮水平和谷丙转氨酶活力(P <0.05),提高甘油三酯含量(P <0.05),而血清中总蛋白、球蛋白、白蛋白、血糖、丙二醛含量和谷草转氨酶活力差异不显著(P >0.05);各试验组均能显著提高血清中溶菌酶、谷胱甘肽过氧化物酶和超氧化物歧化酶活力(P <0.05),但过量添加(2000 mg/kg)会降低其活力(P >0.05)。在基础饲料中适量添加复合益生菌能促进中华鳖的生长、降低饵料系数、提高肠道消化酶活性,同时还具有提高非特异性免疫和抗氧化功能,最适添加量为 1000~2000 mg/kg。  相似文献   
575.
以雪莲果、牛奶和益生菌中的双歧杆菌、嗜酸乳杆菌为原料,研制功能乳饮料,其最佳风味配方为:14%雪莲果汁、25%牛奶、4%直投式益生菌、6%绵白糖,制成的产品口感细腻,酸甜适口,具有浓郁的发酵酸奶风味和雪莲果的清香味。  相似文献   
576.
Labeo rohita fingerlings were fed for 60 days with basal diet (BD) or one of the following experimental diets: DI (BD + B. subtilis); DII (BD + B. subtilis L. plantarum); DIII (BD + B. subtilis P. aeruginosa) and DIV (BD + B. subtilis P. aeruginosa L. plantarum). Various growth and immune parameters were examined at 30 and 60 days postfeeding. The fish group fed DIV diet had better improvement (< 0.05) in weight gain, specific growth rate (SGR) and feed conversion ratio (FCR) than the control and other treatment groups. The serum lysozyme activities, alternative complement pathway activity, phagocytic activity and respiratory burst activity in head kidney macrophages of L. rohita increased significantly in the experimental groups throughout the trial period. Superoxide dismutase increased significantly in the experimental groups, except DI fed group, after 60 days of feeding. A significant improvement in serum IgM level was observed in the treatment groups at 30 days of feeding only. Further, fish fed the DIV diet had highest (< 0.05) postchallenge survival rate (86.6%), followed by DII (73.3%) and DIII (66.6%) against A. hydrophila infection. Considering these promising results, we suggest that a multi‐species probiotic supplementation in equal proportions for 60 days can effectively improve growth and immunity of L. rohita.  相似文献   
577.
在水温15.8~18.6℃下,研究了EM菌液对体质量(13.85±1.44)g中华鲟(Acipenser sinensis)生长、消化酶和非特异性免疫酶活性的影响。实验鱼随机分为对照组和试验组,每组3个重复,每个重复20尾,饲养在室内直径1m、高0.7m的圆形玻纤缸中,分别投喂基础饲料和含EM菌(5.0×10^9 CFU·kg-1饲料)的试验饲料。90d的饲养表明,试验组中华鲟的生长指标均大于对照组,其中增重率及特定增重率显著大于对照组(P〈0.05);试验组鱼淀粉酶、脂肪酶及胃蛋白酶活性均大于对照组,其中试验组肝、胃中淀粉酶活性比对照组高46%和79%、脂肪酶活性高52%和246%,肠、胃中蛋白酶活性比对照组高54%和48%,均呈显著差异(P〈0.05)。试验组鱼肝中过氧化物酶(POD)、超氧物歧化酶(SOD)和过氧化氢酶(CAT)活性均显著大于对照组(P〈0.05),分别提高了29%、33%和34%,脾中除POD外,其他酶活性与肝中相同,但试验组鱼肝、脾中MDA含量比对照组分别小了47%和44%,呈显著性差异(P〈0.05),溶菌酶活性无明显变化(P〉0.05)。由此得出,在饲料中添加EM菌液可提高子中华鲟的消化酶及非特异性免疫酶的活性,促进生长。  相似文献   
578.
将弧菌BC232以105、107 cfu/g和109 cfu/g添加到基础饵料中,投喂仿刺参幼参,每一剂量组均设3个平行,对照组投喂基础饵料,试验在12个盛有100 L过滤海水的塑料桶中进行,每桶放50头幼参,饲养试验进行30 d和45 d。试验结束后分析弧菌BC232对幼参免疫反应和抗病力的影响。试验结果表明,投喂弧菌BC232(107 cfu/g和109 cfu/g)45 d幼参比对照组有较高的体腔细胞吞噬活力(P <0.01)。投喂弧菌BC232菌株105、107cfu/g和109cfu/g 30 d及109cfu/g 45 d幼参体腔液的溶菌酶活力分别显著高于对照组(P <0.05)。与对照组比较,投喂弧菌BC232菌株105 cfu/g 30 d和105、107、109 cfu/g 45 d幼参体腔液中的酚氧化酶极显著提高(P <0.01)。幼参投喂弧菌BC232菌株45 d后用病原菌灿烂弧菌NB13菌株攻毒,各试验组幼参的发病率和死亡率明显低于对照组。本研究表明饵料中添加弧菌BC232可刺激幼参免疫反应,并提高其抗病力。  相似文献   
579.
The aim of this study was to determine the effect of a dietary multi‐species probiotic on growth, gut morphology and immune parameters in Senegalese sole (Solea senegalensis). Fish were fed with two experimental diets, a control diet and the same diet supplemented with the probiotic for 72 days. A sub‐lethal bath challenge with Photobacterium damselae subsp. piscicida was performed after the growth trial. Intestine and blood samples were collected to study gut structure and plasmatic immune parameters. No significant differences were found in growth performance. The analysis of gut morphology showed a significant increase in intestinal villi height of Senegalese sole fed the probiotic. Regarding circulating leucocytes, dietary probiotic supplementation increased thrombocytes levels whereas a decrease in the proportion of lymphocytes was observed. No significant differences were observed in humoural immune parameters. Bath challenge differentially affected leucocyte counts and increased peroxidase activity. This study presents the possibility of using dietary probiotic supplementation to increase Senegalese sole welfare since gut morphology was positively affected. Although the immune response after a bacterial challenge was not modulated by dietary treatment, further studies would be instrumental to unravel eventual dietary benefits on immune mechanisms.  相似文献   
580.
通过细菌16SrRNA基因的高通量测序,对断奶仔猪的肠道菌群结构和饲喂两株单一益生菌(屎肠球菌)后肠道菌群的变化情况和规律进行分析。结果显示,断奶仔猪肠道微生态中拟杆菌门Bacteroidetes和厚壁菌门Firmicutes的细菌所占比例分别为50.5%和42.2%,为绝对优势菌群。饲喂屎肠球菌后,肠道菌群的多样性和细菌丰度均增加;厚壁菌门Firmicutes,变形菌门Proteobacteria、无壁菌门Tenericutes、酸杆菌门Actidobacteria、芽单胞菌门Gemmatimonadetes、放线菌门Actinobacteria细菌的丰度明显上升,而拟杆菌门Bacteroidetes的细菌丰度则发生了明显下降。屎肠球菌所在的肠球菌属Enterococcus的比例虽由0.07%(对照组)上升至0.12%(SF1组)和0.14%(SF2组),但在肠道菌群中所占比例仍然很小,说明屎肠球菌对仔猪肠道微生态的作用主要是影响其他细菌的丰度和多样性进而改变菌群结构。与对照组相比,SF1组的上述菌群变化幅度高于SF2组,通过与3组仔猪生长性能数据的对比,上述菌群变化的幅度与仔猪生长性能提高的程度呈现正相关。  相似文献   
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