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1.
Development of antibiotic resistance in bacteria is a problem of great concern. It is important to establish the convenience of antimicrobial susceptibility tests in animal infections. The aim of this study was to test the susceptibility to antibiotics of Pseudomonas strains isolated from chronic canine otitis externa. We tested 23 strains of Pseudomonas: 19 Ps. aeruginosa, three Ps. fluorescens and one Pseudomonas spp. The most effective antibiotics were tobramycin (100% susceptible), marbofloxacin (91.3%) and ceftazidime (91.3%). Ticarcillin and gentamicin, commonly used for the treatment of otitis externa also showed good results (susceptibility of strains was 86 and 65.2% respectively). Lower susceptibility was found using enrofloxacin (52.1%) probably due to its indiscriminate use. We emphasize the need for a rational policy of antibiotic prescribing in order to prevent the selection of resistant strains.  相似文献   
2.
Brucella ovis causes ram contagious epididymitis, a disease for which a specific vaccine is lacking. Attenuated Brucella melitensis Rev 1, used as vaccine against ovine and caprine brucellosis caused by B. melitensis, is also considered the best vaccine available for the prophylaxis of B. ovis infection, but its use for this purpose has serious drawbacks. In this work, two previously characterized B. ovis attenuated mutants (Δomp25d and Δomp22) were evaluated in mice, in comparison with B. melitensis Rev 1, as vaccines against B. ovis. Similarities, but also significant differences, were found regarding the immune response induced by the three vaccines. Mice vaccinated with the B. ovis mutants developed anti-B. ovis antibodies in serum of the IgG1, IgG2a and IgG2b subclasses and their levels were higher than those observed in Rev 1-vaccinated mice. After an antigen stimulus with B. ovis cells, splenocytes obtained from all vaccinated mice secreted similar levels of TNF-α and IL12(p40) and remarkably high amounts of IFN-γ, a crucial cytokine in protective immunity against other Brucella species. By contrast, IL-1α -an enhancer of T cell responses to antigen- was present at higher levels in mice vaccinated with the B. ovis mutants, while IL-10, an anti-inflammatory cytokine, was significantly more abundant in Rev 1-vaccinated mice. Additionally, the B. ovis mutants showed appropriate persistence, limited splenomegaly and protective efficacy against B. ovis similar to that observed with B. melitensis Rev 1. These characteristics encourage their evaluation in the natural host as homologous vaccines for the specific prophylaxis of B. ovis infection.  相似文献   
3.
Dry farming with soils under natural tephra cover in Lanzarote, Spain   总被引:1,自引:0,他引:1  
Abstract. The volcanic island of Lanzarote (Canary Islands, Spain) is one of the most arid parts of the European Union. During the eruptions of 1730–36, a third of the island was covered with lava and pyroclastic material. In areas under basaltic tephra, an agrosystem has been developed that allows a form of dry farming that has become a key component of the local economy. This article illustrates the effectiveness of the layer of natural tephra mulch in conserving soil and water.  相似文献   
4.
Scrapie is a prion disease characterised by the accumulation of the pathological associated form of cellular prion protein (PrP(SC)) in the central nervous system. Susceptibility to scrapie is associated with polymorphism in the ovine prion protein (PrP) gene. The European Union has implemented scrapie control programs, relying on selective breeding for scrapie resistance; the use of ARR-carrier and the exclusion of VRQ-carrier were recommended. In this study, 4323 individuals from Rasa Aragonesa Sheep breed were genotyped for the PrP gene and the individual estimated breeding values (EBV) for prolificity were calculated. Most represented PrP alleles do not work against prolificity. Only a significant association between VRQ/VRQ genotype and a lower EBV was observed (p = 0.027, eta2 = 0.002). Therefore, avoiding reproduction of VRQ/VRQ individuals would not cause negative effect regarding prolificity.  相似文献   
5.
We studied the simultaneous effect of sex and dose on anaesthesia efficacy to estimate, if possible, the lowest effective dose (LED) for clove oil, tricaine methanesulphonate (MS‐222), 2‐phenoxyethanol (2‐PE) and propofol in mature guppies. LED is the lowest dose needed to reach A5 stage in a mean time of 3 min, with mean recovery (R5) time of 5 min. We used four doses/anaesthetic: 25, 50, 75 and 100 mg/L for clove oil; 120,140,160 and 180 mg/L for MS‐222; 800, 1,000, 1,200 and 1,400 mg/L for 2‐PE, and 7.50, 8.25, 10.00 and 11.25 mg/L for propofol. Each dose was tested on 10 females and 10 males. Morbidity, mortality and behavioural changes were checked on two control groups (10 males and 10 females/group). Sedation (A3), A5 and R5 times were recorded. Significant interactive effect dose*sex on A5 time was found for each anaesthetic agent (pdose*sex < .05). Except for MS‐222 (pdose*sex = .284), significant interactive effect dose * sex on R5 time was found (pdose*sex < .05). A5 time in females tended to be greater than in males, but, in general, R5 times were longer in males. Body size differences between males and females could explain these differences in MS‐222 on A5 time and for clove oil, 2‐PE and propofol on R5 time. No dose simultaneous meet LED′s conditions relating to both A5 and R5 times; therefore the lowest doses inducing A5 in a mean time of 3 min could be a safe guideline for anaesthetic procedure in both male and females.  相似文献   
6.
Abstract. In the extremely arid island of Fuerteventura (Canary Islands, Spain), a traditional water harvesting practice has evolved in slightly sloping areas, which receive runoff water from time to time. The system is particularly effective in the rehabilitation of saline–sodic soils where the improved fertility allows certain crops to be grown, which would not be possible without water harvesting. The influence of the water harvesting on soil fertility was investigated by comparing the properties of the cultivated soils receiving periodic runoff with those of natural control soils that did not receive runoff. The saline–sodic characteristics of the four uncultivated soils were absent from the four cultivated soils which, on average, contained only one quarter of the exchangeable sodium and more than twice the exchangeable calcium content. The clay and silt content of all four of the cultivated soils had been substantially enhanced relative to the control soils, by sediment contained in the runoff.  相似文献   
7.
8.
DNA fingerprinting was used to study the population genetics and paternity of the Rasa Aragonesa sheep (Ovis aries). Using a combination of Hae III and the M13 derived probe pV47, the mean number of bands per individual (5.422 +/- 0.309), the background band sharing coefficient (0.347), the mean population frequency of alleles (0.192) and the mean heterozygosity for bands (0.893) were calculated for 45 individuals from eight different farms in Aragon, northern Spain. Therefore, the estimated probability of missing a wrong paternity was 0.126 for unrelated males, and this probability was 0.438 for full-sibs males. In addition, in a field trial of this technique, paternity was assigned for three ewe-lamb pairs with a probability of 97 per cent in two cases and 77 per cent in one case.  相似文献   
9.
10.
The objectives of the present study were to investigate the effects of inulin and fructooligosaccharides (FOS) on growth performance, whole body and fillet chemical composition and intestinal microbiota of rainbow trouts reared under fish farming conditions. Trouts fed inulin‐ or FOS‐containing diets (5 and 10 g kg?1) exhibited significant (= 0.030) body weight gain improvements compared with controls. An increase in gross energy (= 0.044) and Ca content (= 0.034) in the whole body of trouts was observed for prebiotic treatments. A decrease in crude protein content (= 0.009) and a tendency to increase total lipid and gross energy contents (= 0.090 and = 0.069, respectively) were detected in the fillet tissue for prebiotic treatments. These results clearly indicate that inulin and FOS improved the intestinal absorption of Ca and that the increased amount was predominantly incorporated into bone tissue. Inulin reduced (= 0.027) the intestinal population of Vibrio spp. in the distal region to such an extent that no viable counts were detected. The presence of Flavobacterium spp. was not detected in any group, and the numbers of Aeromonas spp., Pseudomonas spp. and Gram‐positive bacteria were not affected (> 0.05).  相似文献   
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