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51.
Effects of lactulose (lac) as feed additive on chyme and feces quality in pigs (reared piglets: n = 10; fattening pigs: n = 20) were tested. Furthermore, fattening pigs were experimentally infected with Salmonella Derby (orally 2.6 × 108 cfu/pig, single dose infection on 1 day) to examine potential prophylactical effects. Pigs were fed a conventional diet ad libitum (in the control group without lac, in the experimental group including lac: 28.6/26.9 g lac/kg dry matter). In piglets and fattening pigs lac intake did not alter fecal dry matter (DM) content or feces pH. Contrary to findings in human beings only small amounts of lac reached the hindgut, although higher lac concentrations were measured in ileal chyme (in piglets: 10–40 g, in fattening pigs 40–70 g lac/kg DM of chyme). Lac ingestion led neither to increased concentrations of lactic acid or volatile fatty acids (vfa) nor to reduced pH data in chyme of small intestine, but in cecum and colon contents higher vfa concentrations (significant effects in piglets) were measured. Furthermore, lac ingestion resulted in reduced ammonia levels in small and large intestine contents. But no protective effects of lac ingestion were recognized when fattening pigs were infected orally with Salmonella Derby. Due to the fact that only parts of lac reach the hindgut there are doubts, whether lac can lead to comparable dietetic effects in pigs as known from human beings (laxation, forced elimination of bacteria a.s.o.). The obtained results in pigs underline the necessity of experimental studies in the target species before substances are used and recommended for dietetic purposes in feeding of pigs. 相似文献
52.
The objective of this experiment was to investigate the effect of non-starch polysaccharide (NSP) solubility and inclusion rate on gut health and development, performance and risk of post weaning enteric disorders (PWED) using NSP sources known not to affect digesta viscosity. The experiment consisted of a 2 × 3 factorial combination of NSP type (sNSP vs insoluble NSP (iNSP); inulin vs purified cellulose) and inclusion level (50 vs 100 vs 150 g/kg). Piglets were weaned at 28 days (day 0) and fed ad libitum until slaughter on day 14. There were no incidences of PWED. NSP solubility had little effect on performance, but sNSP diets resulted in lower caecal and colonic pH and higher colonic Lactobacilli to coliform ratio compared to iNSP diets. Increasing NSP levels significantly reduced caecal and colonic pH but decreased empty body weight percentage (P = 0.067). These results suggest that gut health may benefit most from diets containing appropriate sources of predominantly sNSP rather than iNSP. The optimal level of such sNSP will likely depend upon the level of risk of PWED in order to balance the trade off between maximising performance and improving gut health. Effects of NSP feeding under a higher infectious pressure remains to be assessed. 相似文献
53.
W.I. Kuller H.M.G. van Beers-Schreurs N.M. Soede P. Langendijk M.A.M. Taverne B. Kemp J.H.M. Verheijden 《Livestock Science》2007,108(1-3):99-101
The aim of the study was to measure the effect of creep feeding during lactation on net absorption in the small intestine at 4 days after weaning. Intermittent suckling was used to increase creep feed intake during lactation. Creep feed containing chromic oxide was provided. Based on the colour of the faeces, piglets were classified as ‘eaters’ or ‘non-eaters’, respectively. At day 4 after weaning, an in vivo small intestine segment perfusion test was performed at 5 sites along the small intestine in 24 piglets (12 eaters and 12 non-eaters). At both sides of each intestinal segment a tube was fitted to perfuse and drain fluid in order to assess net absorption. Net absorption was higher in eaters than in non-eaters (P < 0.001). Net absorption varied greatly between and within piglets and was highest in the caudal segments of the small intestine (P < 0.001). These data suggest that creep feeding could be a useful tool in the prevention of post-weaning diarrhoea. 相似文献
54.
55.
K. Haverson F. Zuckermann A. Saalmüller J. Lipp B. Aasted C. R. Stokes 《Veterinary immunology and immunopathology》1998,60(3-4):351-365
Fifty-nine monoclonal antibodies (mAb) were assigned to the adhesion section of the Second International Swine CD Workshop. They were analysed for their reactivity to selected lymphoid cell populations, as well as to non-lymphoid cell lines. Cell lysate ELISAS and Western Blot analyses were also carried out. As a result, thirteen separate cluster groups emerged (p>0.95). Workshop assignments for adhesion molecules were made: wCD29/49 for mAbs UCP1D2 (#133) and FW4-101 (#165), and PNK-I (#194) and MUC76A (#025) could be assigned to wCD18. For one cluster (FQ1D7, #161 and 2F4, #069) the cellular distribution and MW were characteristic for MHC Class II, and another cluster comprising several antibodies which appeared to recognise MHC Class I. Other clusters could not be assigned to cell surface structures known to be linked to cellular adhesion, however, two further antibodies, 335-2 (#112) and FG1F6 (#156), could be added to SWC1, and the new SWC8 was defined by MIL3 (#077) and MUC20A (#029), binding a ligand of 29–32 kDa. Clustering for these two antibodies was confirmed by blocking studies. The cellular distribution is known for MIL3, recognising an epitope present on granulocytes, B cells, and a subset of T cells expressing CD8 at high intensity. 相似文献
56.
R.H Dunlop S.A McEwen A.H Meek R.C Clarke W.D Black R.M Friendship 《Preventive veterinary medicine》1998,34(4):1610-305
Logistic regression was used to model associations between antimicrobial treatment and resistance among fecal Escherichia coli of finisher pigs at the farm level. Four sets of potential risk factors representing different levels of refinement of antimicrobial use on farms were modelled on resistance to antimicrobials. Final models for each antimicrobial were constructed from treatment and management variables significant on initial screening, and corrections for overdispersion were made. In general, in-feed antimicrobial treatment of pigs was more consistently associated with an increased risk of resistance than individual-animal treatment. Antimicrobial treatment in starter rations was significant in final models of resistance to ampicillin, carbadox, nitrofurantoin, sulfisoxizole, and tetracycline. Treatment in grower–finisher rations was significantly associated with resistance to ampicillin, spectinomycin, sulfisoxizole, and tetracycline. There was little evidence that in-feed antimicrobials increased the risk of resistance to gentamicin, which is a drug used only for individual-pig treatment in this study population. These results suggest that antimicrobial medication of rations of post-weaning pigs selects for and maintains antimicrobial resistance among E. coli of finisher pigs. Although resistance was common on farms that did not medicate rations of post-weaning pigs, the results indicate that antimicrobial use does increase the risk of resistance to the antimicrobials studied. 相似文献
57.
58.
寻找温度与猪的生长之间关系的有关数据,得出在临界温度下,育成猪的生长随温度变化而变化的规律;总结了我国各地现有的各种养猪舍建筑形式;分析、探索了冷季提高、维持猪舍环境温度的各种方式;通过估算其成本和它们各自能带来的经济效益经行经济性比较得出全封闭式暖床保温。 相似文献
59.
猪肌细胞生成素基因的研究进展 总被引:1,自引:0,他引:1
综述猪肌细胞生成素(MyoG)对猪产肉量影响的作用机制和猪肌细胞生成素基因的定位及结构,并分析其PCR-RFLP遗传变异. 相似文献
60.
试验采用96头杜洛克猪,这些猪是用反相选择跛行的方法所建立的两个品系的第7代后裔,测定其前肢的尺骨长,尺宽,足长和体长是否有差异。品系分为跛行组和健康组,后者表示在前肢结构上发育良好。所有猪都在二个特定日龄测定,平均117日龄和159日龄,并在每圈猪平均体重达到95kg时进行第三次测量,结束试验。资料用变量分析,混合方程包括品系、重复批次、饲料和性别的影响,并以体重或日龄作协方差分析。健康组猪比跛行组猪足长较长(P<0.01),在117日龄大7%,159日龄大14%,在试验结束时大30%。健康组猪的足宽则几乎和跛行组相等。对不同程度跛行选择的影响也表现在猪的体形方面,健康组猪比跛行组猪在159日龄时体长和尺骨长相对较短,在达到上市体重时体长轻短。对不同程度跛行的选择已使社洛克猪的结构发生了许多变化。 相似文献