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21.
Co‐culture of cumulus‐oocyte complexes (COCs) with denuded oocytes (DOs) during in vitro maturation (IVM) was reported to improve the developmental competence of oocytes via oocyte‐secreted factors in cattle. The aim of the present study was to investigate if addition of DOs during IVM can improve in vitro fertilization (IVF) and in vitro culture (IVC) results for oocytes in a defined in vitro production system in pigs. The maturation medium was porcine oocyte medium supplemented with gonadotropins, dbcAMP and β‐mercaptoethanol. Cumulus‐oocyte complexes were matured without DOs or with DOs in different ratios (9 COC, 9 COC+16 DO and 9 COC+36 DO). Consequently; oocytes were subjected to IVF as intact COCs or after denudation to examine if DO addition during IVM would affect cumulus or oocyte properties. After fertilization, penetration and normal fertilization rates of zygotes were not different between all tested groups irrespective of denudation before IVF. When zygotes were cultured for 6 days, no difference could be observed between all treatment groups in cleavage rate, blastocyst rate and cell number per blastocyst. In conclusion, irrespective of the ratio, co‐culture with DOs during IVM did not improve fertilization parameters and embryo development of cumulus‐enclosed porcine oocytes in a defined system.  相似文献   
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Despite the importance of swine intestinal health, there are no easy-to-use and cost-efficient methods to evaluate it under field conditions for sows. To provide some indication about intestinal health, pH of faeces could be used but reference values for the currently high-performing commercial sow breeds are missing. In response, faecal pH of healthy sows from three different herds (herd A: 230 sows, herd B: 350 sows, herd C: 500 sows) was measured throughout the reproductive cycle. Within each herd, 10 sows were selected and rectal faeces samples were collected at different time points during the reproductive cycle: day 90 of gestation, day 1, 7, 14 and 21 of lactation, 7 days post-weaning and day 30 of the next gestation. In addition, data on sow body condition (back fat), feed composition and coarseness of the feed were collected. For individual pH measurements, the pH ranged from 6.30 to 7.93. However, for all herds together, the average faecal pH value of the sows throughout the reproductive cycle ranged from 6.89 to 7.15. Also, the variations due to sow and time of sampling during the reproductive cycle were low with coefficients of variation of less than 5%. The results from the pairwise comparisons of the statistical model showed that in the last stages of lactation (i.e., at day 21), significantly lower average pH values (p ≤ .05) are expected when compared to earlier stages of lactation (days 3 or 7), or at day 7 post-weaning or compared to day 30 of the next gestation. Bearing its limitations, our study provided reference faecal pH values from high-performing commercial sows under field conditions and as such they could be used directly in the field. Yet, further research is needed to provide more information on the factors affecting pH values throughout the reproductive cycle of the sow.  相似文献   
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The use of a new method for characterizing humic acids based on the measurement of the cobaltihexammine cation exchange capacity (CEC) vs. pH is examined. The method was first verified on a macroporous weak-acid cation exchange resin: charge vs. pH curves and pK values from cobaltihexammine adsorption identify with results from discontinuous acid-base titrations at high ionic strength (5 M). Similar agreement was obtained for humic acids from a Podzol soil: the cobaltihexammine-CEC identifies with the macromolecular charge (from continuous acid-base titrations) at ionic strength of 3 and 5 M, but slightly underestimates (5%) the humic acid charge at 1 M ionic strength. The cobaltihexammine method is suitable for determining the potentially available charge in the pH range 2 to 12 and the intrinsic pK values of humic acids.  相似文献   
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Two short sequences, situated in the bacterial 23S rDNA gene, were used as primers for the PCR detection of Erwinia amylovora bacteria. All 34 E. amylovora strains tested, coming from different geographical and host plant origins and of different virulence, produced a 565-bp PCR fragment. The E. amylovora bacteria could be discriminated from all other phytobacteria with which no PCR product was observed. Only Escherichia coli bacteria were cross-recognized by the production of a weaker PCR band of similar size to E. amylovora . In a fast PCR protocol, where two temperatures were cycled, E. amylovora in pure culture could be detected on gel at concentrations as low as 3 × 102 cfu mL–1. This corresponds to a detection limit of 1.5 bacteria per PCR. However, reliable PCR detection in woody host plant tissue was only obtained with PVP/PVPP-treated sample extracts. Using E. amylovora -spiked plant extracts and extracts of fruit tree shoots artificially infected with E. amylovora , the PCR detection sensitivity was determined to be 6.6 × 102 cfu mL–1 of extract. Starting from the plant samples, the PCR detection results were visualized on gels within 5 h.  相似文献   
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The present study investigated the prevalence of uroliths in fattening pigs and assessed the composition of these urinary tract concrements. In total, 2,432 urinary bladders were sampled in the slaughterhouse and checked for abnormal content. Urinary samples were analysed microscopically, and samples of the urinary bladder wall were tested for histological signs of inflammation. The composition of the concrements was examined by infrared spectrophotometry. Macroscopic and microscopic abnormalities were detected in 8.4% and 52.8% of the samples respectively. Magnesium ammonium phosphate (struvite), calcium oxalate dihydrate (COD), calcium carbonate (calcite), calcium oxalate monohydrate (COM) and amorphous crystals were detected. Analysis of stones showed COD in all samples in different proportions. The calcium content of examined stones was always considerable (up to 34%), in contrast to the magnesium content which represented max 1.9%. Struvite was found in one third of the samples, but was never part of stones and grit. COD crystals were the second most common microscopic crystal. These COD crystals and some COD stones had a rectangular shape, and therefore, they can be harmful to the bladder mucosa. In conclusion, uroliths are present in a large proportion of male fattening pigs, and consequently, urinary concrements pose a life‐threatening risk for urethra obstruction in male pigs. Further research is warranted to identify potential risk factors for urolithiasis and microscopic crystals.  相似文献   
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Reference values have been established for serum biochemical parameters in sows from high producing pig herds. In total, 132 clinically healthy sows from eight breeding herds were serially sampled three weeks and one week before farrowing, and at one week and three weeks after farrowing. Fourteen serum biochemical parameters, focusing mainly on energy and protein metabolism, hepatobiliary and kidney function and inflammation, were investigated. The reproductive state significantly influenced the investigated parameters, other than for urea and non-esterified fatty acids. First parity sows showed higher concentrations of gamma-glutamyltransferase, phosphorus and haptoglobin, and higher albumin/globulin and haptoglobin/albumin ratios compared to sows with 2 parities. The concentrations of creatinine, globulin and total protein however were lower in first parity sows. Between-herd variations were especially high (>50%) for gamma-glutamyltransferase, alkaline phosphatase and non-esterified fatty acids. Serum biochemical parameters constitute an important diagnostic tool to assess the health status of sows, but to interpret the outcome properly, it is important to consider reproductive state and parity.  相似文献   
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Isospora suis is a widely prevalent and economically important parasite. The antiprotozoal compound, toltrazuril, was given as a single treatment to piglets without clinical signs in 10 herds. The daily weight gain (DWG) and mortality between the treatment date and weaning was compared on each herd in 10 treated and 10 control litters. The faeces of control litters were examined for oocyst excretion. In six herds, no oocysts were detected and treatment had no effect on DWG or mortality. In four pig herds, oocysts were detected and toltrazuril treatment significantly improved DWG by 25 g (P=0.003). Mortality rate was not affected. The partial economic benefit of toltrazuril treatment in positive herds was 0.20 euros per piglet. A single toltrazuril treatment of piglets in herds without clinical signs of isosporosis but with oocysts detected significantly improved DWG and was considered economically justified on each farm.  相似文献   
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