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41.
SUMMARY: Johne's disease was diagnosed in 10 alpacas ( Lama pacos ) in Australia between February 1993 and May 1994. Eight of the animals were between 12 and 24 months of age, one was a 6-year-old female, and one was a 4-year-old male. Five, including the 6-year-old and the 4-year-old alpacas, showed weight loss and diarrhoea before death or slaughter. The other cases showed no clinical signs of Johne's disease but 4 gave a positive result on faecal culture and one gave a positive result on testing with the caprine ACID assay and had acid-fast organisms in its faeces. At necropsy, all cases had grossly enlarged mesenteric lymph nodes. Johne's disease was diagnosed after histological examination of the lymph nodes with conventional culture and polymerase chain reaction testing of tissue samples. This report outlines the clinical, epidemiological, and pathological findings in these cases.  相似文献   
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Fermented liquid feed is feed that has been mixed with water at a ratio ranging from 1:1.5 to 1:4. By mixing with water, lactic acid bacteria and yeasts naturally occurring in the feed proliferate and produce lactic acid, acetic acid and ethanol which reduces the pH of the mixture. This reduction in pH inhibits pathogenic organisms from developing in the feed. In addition, when this low pH mixture is fed, it reduces the pH in the stomach of pigs and prevents the proliferation of pathogens such as coliforms and Salmonella in the gastrointestinal tract. For piglets, the use of fermented liquid feed offers the possibility of simultaneously providing feed and water, which may facilitate an easier transition from sow’s milk to solid feed. Secondly, offering properly produced fermented liquid feed may strengthen the role of the stomach as the first line of defense against possible pathogenic infections by lowering the pH in the gastrointestinal tract thereby helping to exclude enteropathogens. Finally, feeding fermented liquid feed to pigs has been shown to improve the performance of suckling pigs, weaner pigs and growing-finishing pigs. In this review, current knowledge about the use of fermented liquid feed in pig diets will be discussed. This will include a discussion of the desirable properties of fermented liquid feed and factors affecting fermentation. In addition, advantages and disadvantages of fermented liquid feed will be discussed including its effects on gastrointestinal health, intestinal pH and the types of bacteria found in the gastrointestinal tract as well as the effects of fermented liquid feeds on pig performance.  相似文献   
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Contents Bovine oocytes and embryos produced in vitro were studied to determine the mitochondrial pattern of distribution, segregation and activity using DIOC 6 and Jc-1 fluorescence. The highest fluorescence level observed in mature oocytes was taken as 100% activity and six activity levels were estimated as follows: (1) 0%, (2) 1-15%, (3) 16-30%, (4) 31-50%, (5) 51-75% and (6) 76-100%. Three patterns of mitochondrial distribution were found: (1) diffused throughout the cytoplasm in oocytes and embryos, (2) pericytoplasmic in oocytes and embryos, and (3) perinuclear only in embryos. The segregation of mitochondria in blastomeres showed two distinct patterns: (1) symmetrical with an even mitochondrial population, and (2) asymmetrical with different numbers of mitochondria in each blastomere. In immature oocytes, mitochondrial activity was very low and the distribution was diffuse or negligible, while in mature oocytes the activity was high and the distribution was diffuse or pericytoplasmic. Competent embryos up to the 16-cell stage showed intermediate levels of activity (16-50%) but activity decreased thereafter up to the blastocyst stage. Non-competent embryos showed low levels of activity (1-15%) at all stages. These results suggest that mitochondria might play an important role during early development and that a minimum threshold of activity regulates the potential competence for reaching the blastocyst stage.  相似文献   
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The main objective of this work was to study the effects of banana flour as energy sources on broiler performance. Seventy‐five broilers were randomly distributed into five groups each with 15 broilers (n = 15 broilers/group). The broilers were grouped to maize–soybean meal diet as control, T1: (5% of banana flour), T2: (10% of banana flour), T3: (15% of banana flour), and T4: (20% of banana flour). The parameters analyzed in this research were body weight, daily weight gain, and daily feed intake at days 0, 10, 20, 30, and 40. The results showed no significant effects on body weight during the time of assessment, showing healthy values (>1,400 g) in all treatments (p > .05). Daily Weight gain was affected significantly during the days of assessment (p < .05). In all treatments and at different days of assessment, T3 showed the highest daily weight gain at day 10 (37.56 ± 4.52 g) compared to the other experimental treatments. Regarding daily feed intake, significant differences were observed at day 10 in the control and treatments T1, T2, T3, and T4 compared to days 20, 30, and 40 (p < .05), being the highest value for T1 (35.14 ± 2.77).  相似文献   
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The objective of this study was to evaluate different concentrations of growth hormone (GH) on the development of bovine preantral follicles cultured included in the ovarian tissue (in situ) on the rates of morphologically normal, viable, primordial and developing follicles, as well as the oocyte and follicle diameter and ultrastructural analysis. Ovarian fragments collected from cows with no cross‐breeds defined were cultured in situ for 1 and 7 days in minimal essential medium (α‐MEM+) supplemented with different concentrations of recombinant human GH (0, 10, 25, 50 ng/ml). The ovarian fragments non‐cultured (control) and cultured were processed for classic histology, mechanical isolation and electron transmission microscopy (MET). The parameters underwent anova (Tukey′s and Dunnett′s tests) and chi‐square test (χ2). After 7 days of culture, the treatment with 50 ng/ml GH showed no differences with fresh control (p > 0.05) and had greater effectiveness than in the 0, 10 and 25 ng/ml GH concentrations of the morphologically normal follicles. Regarding the primordial follicles, a reduction was observed in the 50 ng/ml GH concentration concomitant with the significant increase in developing follicles, differing from both the fresh control and the other GH concentrations tested. In addition, 50 ng/ml GH showed a larger follicle and oocyte diameter when compared to the other treatments cultured. Similar structures were ultrastructurally observed in the control group, 50 ng/ml GH. Follicles cultured in 10 ng/ml GH showed nuclear invagination, vacuoles and lesioned basal membrane. Hence, it is concluded that 50 ng/ml GH is the most effective concentration for the development of preantral follicles cultured in situ.  相似文献   
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Wisent, or European bison (Bison bonasus), is listed as “vulnerable” on the IUCN Red List of Threatened Species and is therefore protected by international law. For the first time, a Wisent embryo has been obtained in vitro. This procedure creates a new opportunity to protect and increase Wisent reproductive potential and thereby opens new possibilities for the establishment of a controlled and broad reserve of the gene pool.  相似文献   
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