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排序方式: 共有239条查询结果,搜索用时 15 毫秒
1.
A Lindner A Wahdati H Sommer 《Berliner und Münchener tier?rztliche Wochenschrift》1992,105(7):239-242
GSH-Px activity in blood and plasma of 269 horses was determined and interrelated to age, sex, and type of use or breed. Furthermore values in blood were related to hematocrit and hemoglobin contents. Trotters and riding horses had higher GSH-Px activities in plasma as well as in blood (0.83 +/- 0.22 and 0.79 +/- 0.23 U/ml plasma or 27.2 +/- 4.3 and 24.0 +/- 7.0 U/ml blood) than Thoroughbreds in training and yearlings (0.61 +/- 0.,14 and 0.56 +/- 0.16 U/ml plasma or 20.6 2 +/- 6.9 and 24.6 +/- 4.3 U/ml blood). 3 to 6 years old Thoroughbreds had higher GSH-Px-activities than 1 to 2 years old ones. Colts and fillies did not have differing values. 相似文献
2.
A. Lindner Dr med vet l; P. von Wittke Dr. med vet; M. Schmald J. Kusserow H. Sommer Dr habil Dr med vet 《Journal of Equine Veterinary Science》1992,12(1)
Lactate kinetics in whole blood of horses was investigated after exercise of differing velocities and duration. The following categories of exercise were used: A: <11 m/second and >180 seconds (n=35), B: >11 m/second and <180 seconds (n=17) and C: <11 m/second and <180 s (n=10). The mean peak lactate concentration determined in horses in category A was 4.49 ± 2.21 mmol/1, in B, 16.32 ± 4.81 mmoVl and in C, 4.58 ± 1.59 mmol/l. While the maximum lactate concentrations in categories A and C were always found immediately after the exercise, the peaks in category B were measured between the first and tenth minute after exercise. Mean lactate concentrations measured at 2-minute intervals after bouts of category-B exercise tended to stabilize 3 to 10 minutes after exercise; however, mean lactate concentrations measured during the intervals before and after the peak value differed significantly. The lactate concentration returned to pre-exercise levels within 20 minutes after exercise bouts of category C, but remained above pre-exercise levels up to 60 minutes after bouts of category-A and -B exercise. It was concluded that, for an evaluation of lactate data after intensive anaerobic exercise, sequential blood sampling at 2-minute intervals for a period of up to 12 minutes after exercise is necessary. Less frequent sampling may be a reason for the often described irreproducibility of lactate concentrations in horses. After aerobic or mild anaerobic exercise, one sample is sufficient, but it has to be taken as soon as possible after exercise. 相似文献
3.
Springer S Lindner T Steinbach G Selbitz HJ 《Berliner und Münchener tier?rztliche Wochenschrift》2001,114(9-10):342-345
Hybrid swine (Landrace x Pietrain) aged 3-4 weeks were immunized twice at an interval of 3 weeks solely by the oral route and by the oral/parenteral route to evaluate the efficacy of a live S. Typhimurium vaccine. In each experiment a control group was run without vaccination. The animals were challenged at the age of 8-10 weeks by oral test infection with a labelled S. Typhimurium DT 104 strain. An ELISA was used to establish the presence of antibodies to S. Typhimurium in serum samples, coupled with clinical investigation. The presence of the challenge strain in the ileal and caecal mucosa and in the ileocolic lymph nodes was investigated quantitatively using the Koch plating method to determine the degree of colonization of those organs at the time of slaughter. The clinical course of disease was used to assess the success of vaccination. However, it was not possible to trigger, in a reproducible manner, clinical signs of disease in unvaccinated animals through infection. The vaccinated animals had a significantly lower (p < 0.05) colonization of the ileal and caecal mucosa than the unvaccinated animals. This was also seen to a lesser degree for the ileocolic lymph nodes. 相似文献
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Steinbach G Methner U Springer S Lindner T Selbitz HJ 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(3-4):124-129
LPS antibody reaction of S. Typhimurium was detected in a total of 111 two- to ten-week-old pigs, which had been exposed to experimental oral infection with this serovar in 16 separate experiments. The total antibody level was determined according to the meat juice ELISA provided for the Salmonella control programme and the antibody concentrations of the isotopes IgG1, IgG2, IgA and IgM. Although there were significant differences between the individual experiments with respect to the reaction intensity and proportion of the individual immune globulin isotypes, the following general statements on the dynamics of the antibody reaction can be made: Clearly elevated antibody levels could be observed one week after the onset of infection. After one and two weeks, respectively, 22.5 and 52.9% of the infected animals showed antibody levels which were to be evaluated as positive in the sense of the Salmonella control programme (> or = 40%). While the concentration of the IgM-related antibodies decreased again during the second week already, the antibody concentration of IgG1 and IgG2 continued to increase until the end of the experiment after 3 weeks. The clear differences in the reactions between the experiments cannot be explained solely by defined conditions of infection such as strain of infection, infective dose or age of the pigs. Obviously, other non-defined or non-recognized factors may have a decisive influence on the dynamics of the antibody reaction in the animal groups. 相似文献
8.
Springer S Lehmann J Lindner T Thielebein J Alber G Selbitz HJ 《Berliner und Münchener tier?rztliche Wochenschrift》2000,113(6):246-252
Within the works for the registration of a new live Salmonella Enteritidis vaccine for layers, safety and efficacy of the vaccine strain were tested by experimental studies. After oral administration of the single and the tenfold dose, no incompatibility reactions were seen in day-old chicks. The laying performance and the egg weight were not affected by the vaccination of the chickens during the laying period. There was only a limited period in which the excretion of the vaccine strain and its persistency in organs were seen. Even after the threefold oral vaccination the vaccine strain could not be isolated from eggs and internal organs of slaughtered chickens. Moreover, a high safety for non-target animals (cattle, pigs) could be established. Studies with BALB/c mice proved that a cell-mediated immunity and the development of complement-fixing antibodies is induced by the vaccine. Efficacy studies in target animals were carried out by a proved dependable oral challenge system that reproduces a latent infection with marked S. Enteritidis strains and by means of the seeder-bird method. The test results demonstrate that the vaccination is capable to avert or to reduce an infection significantly. 相似文献
9.
Simulation study of the competitive ability of erect, semi-erect and prostrate cowpea (Vigna unguiculata) genotypes 总被引:1,自引:1,他引:1
Ecophysiological simulation models provide a quantitative method to predict the effects of management practices, plant characteristics and environmental factors on crop and weed growth and competition. The INTERCOM interplant competition model was parameterised, calibrated by monoculture data for three cowpea (Vigna unguiculata) genotypes that differed in growth habit, common sunflower (Helianthus annuus) and common purslane (Portulaca oleracea), and used to simulate competition of cowpea cover crops with sunflower or purslane. The simulation results were compared with observations from field competition experiments in 2003 and 2004. INTERCOM more accurately simulated actual field data for the competition of cowpea genotypes and sunflower than companion field experiments for the competition of cowpea and purslane. The validated simulation model of cowpea and sunflower at two densities was used to study the effects of cowpea growth habit on final biomass production of cowpea and sunflower. The model suggested that erect growth habit was more competitive than semi‐erect and prostrate growth habit, when cowpea genotypes were grown with sunflower. Cowpea leaf area distribution was important to higher cowpea biomass production, while cowpea height growth was important to reduce sunflower biomass. Our simulation approach is suggested as a method for crop breeders to gauge the likely success of selection for competitive crops before undertaking expensive long‐term breeding experiments. 相似文献
10.
A Lindner Y Will J Chrispeels 《Berliner und Münchener tier?rztliche Wochenschrift》1990,103(12):411-416
Reference values for Cortisol, T4 and T-Uptake, determined with the Fluorescence-Polarization-Immunoassays (FPIAs) in blood-plasma of different horse groups were established. The highest Cortisol values were measured in blood samples from thoroughbred racehorses and riding horses taken between 7 and 8 a.m. (181 +/- 37 and 268 +/- 43 nmol/l), the lowest gained between 5 and 6 p.m. (69 +/- 45 and 85 +/- 32 nmol/l respectively). Peak values for T4 in riding horses were found in blood samples collected between 1 and 2 p.m. (28.2 +/- 5.7 nmol/l) followed by the samples taken at 5-6 p.m. and 7-8 a.m. T-Uptake values did not show a diurnal variation. Values of thoroughbred racehorses were much lower than in thoroughbred broodmares and riding horses (0.11 +/- 0.03, 0.18 +/- 0.03 and 0.24 +/- 0.05 units). The blood samples collected on 5 successive days showed significant variations for Cortisol. T4-values were stable whilst T-Uptake had small variations. 相似文献