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31.
A free-ranging, adult male Florida panther (Puma concolor coryi) was immobilized and evaluated for hematuria following routine capture. Prior to anesthetic recovery, the panther was fitted with a telemetry collar. After an initially quiet recovery, the panther began thrashing in the transport cage, and was again immobilized. Pink foam was evident from the nostrils, and crackles were ausculted over the chest, indicating pulmonary edema. Postobstructive pulmonary edema was diagnosed based on history, clinical signs, radiographic evaluation, and blood gas analysis. The animal was treated intensively for several hours with diuretics, oxygen, and manual ventilation. The panther responded rapidly to therapy and was released back into the wild 48 hr after presentation. Postobstructive pulmonary edema, also called negative-pressure pulmonary edema, may be underrecognized in veterinary medicine. In this case, the telemetry collar, in conjunction with anesthetic recovery in a small transport crate, may have contributed to tracheal obstruction. Wildlife veterinarians and biologists should be aware of the risk of airway obstruction when placing tracking collars, and animals should be continuously monitored during anesthetic recovery to ensure the presence of a patent airway.  相似文献   
32.
West Nile virus has been associated with numerous bird mortalities in the United States since 1999. Five avian species at three zoological parks were selected to assess the antibody response to vaccination for West Nile virus: black-footed penguins (Spheniscus demersus), little blue penguins (Eudyptula minor), American flamingos (Phoenicopterus ruber), Chilean flamingos (Phoenicopterus chilensis), and Attwater's prairie chickens (Tympanuchus cupido attwateri). All birds were vaccinated intramuscularly at least twice with a commercially available inactivated whole virus vaccine (Innovator). Significant differences in antibody titer over time were detected for black-footed penguins and both flamingo species.  相似文献   
33.
The racing careers of 2, 3, 4, and 5-year-old Thoroughbreds and French trotters born in France between 1995 and 1999 were analysed. The horses were evaluated on a set of traits, with particular attention to annual or career earnings and number of starts.

As expected, the distributions of earnings corrected for year, age and sex are very skew and thus inappropriate for breeding value estimations. However, Log transformation results in near normal distributions more suitable for this purpose.

Another problem of annual or career earnings required a more complex approach. As most horses did not win any money in France (67% of the trotters and 41% of the Thoroughbreds), it is difficult to correctly evaluate these horses. On the other hand, a linear adjustment of the Log of earnings by the Log of the number of starts (exponential adjustment of the earning index) leads to regression coefficients close to 1. It justified the use of the Log of earnings per start and explained its higher heritability in literature. A quadratic adjustment of the Log of earnings by the Log of the number of starts (sigmoid adjustment of the earning index) improves the adjustment for the Thoroughbred only and should be implemented for these horses.

The probability of a horse to be placed according to the number of starts was also studied. It is shown that the observed percentage of non-placed horses ps according to the number of starts, s, is in all cases inferior to the expected percentage (ps < p1s). Therefore, races of the same horse cannot be considered as independent events. The percentage of horses placed and the mean earnings for each age can be combined in order to estimate the economical weights for each age class. Economical weights for the French trotter were 0.00, 0.21, 0.40, and 0.39 for 2, 3, 4, and 5-year olds respectively. They were 0.11, 0.45, 0.26 and 0.18 respectively for Thoroughbreds of the same age categories. The current tendency to move from annual or career criteria towards criteria at the race level is discussed. However, the question on how to evaluate the important proportion of horses born that never appeared in a race still remains open and should focus future research.  相似文献   

34.
35.
Spores of the vesicular-arbuscular mycorrhizal endophyte Glomus caledonius (Nicol. and Gerd.) Trappe and Gerdemann readily germinated in the absence of soil or host roots. Hyphal growth was improved by incorporation of nutrients into the medium and by the addition of pieces of cotyledon from boiled seeds, but was still dependent on the spore reserves. The response of ungerminated and pregerminated spores to inhibitors of protein and nucleic acid synthesis (cycloheximide, actinomycin D, proflavine hemisulphate, 5-fluorouracil and ethidium bromide) resembled those of saprophytic fungi more than other obligate biotrophs.  相似文献   
36.
Antimicrobial flavonoids from the stem bark of Erythrina burttii   总被引:1,自引:0,他引:1  
The chloroform extract of the stem bark of Erythrina burttii showed antifungal and antibacterial activities using the disk diffusion method. Flavonoids were identified as the active principles. Activities were observed against fungi and Gram(+) bacteria, but the Gram(-) bacteria Escherichia coli was resistant.  相似文献   
37.
The value of eucalyptus oil for medicinal purposes is based largely on its cineole content. The prime commercial species for cineole production in Australia is Eucalyptus polybractea (blue mallee). Despite the long history of blue mallee harvesting in Australia, there has been little research on the establishment of plantations of the species or on the efficacy of short-rotation coppice cultivation with respect to the consistency of oil yield and quality from rotation to rotation. This study aims to assess if subsequent coppice oil traits reflect sapling traits and if the coppice oil traits under short-rotation cultivation are consistent from one rotation to the next. A trial plantation was established in a key eucalyptus oil harvesting district in Victoria. Firstly, the oil-related traits of 20 saplings harvested 3.5 years after planting were compared with those of their subsequent coppice harvested after 12 months regrowth. Despite the expected differences in total biomass, the oil-related traits of blue mallee saplings were mostly well reflected in their subsequent coppice. Total above ground biomass and foliar oil concentration were significantly related between saplings and coppice, and cineole proportion showed a Pearson's correlation of 0.93 between harvests. Nevertheless, the mean foliar oil concentration in the coppice was 148 mg g−1 dw compared with 107 in the saplings, and the coppice foliage, on average, showed significantly reduced cineole with a mean of 87% in the saplings (maximum of 95.6%) compared to a mean of only 80% in the coppice (maximum of 87.0%). Secondly, the oil traits of 20 coppice plants from one 12-month harvest rotation to the next were compared. Again, total above ground biomass, foliar oil concentration and cineole proportion were significantly related between the harvests, with cineole proportion having a Pearson's correlation of 0.90 between rotations. The coppice between rotations were remarkably consistent in terms of biomass and oil traits and indeed mean coppice cineole yields were 28.6 and 29.7 g in rotations 1 and 2, respectively. The results support the screening of key oil-related traits in saplings for the selection of elite genotypes for plantations, and the use of short-rotation cultivation of the plantations for continued oil harvesting. Furthermore, no relationship was observed between biomass and oil concentration in the blue mallee saplings or coppice, suggesting selection gains in a given key oil trait will not result in losses in another.  相似文献   
38.
Prewein C  Vagner M  Wilhelm E 《Tree physiology》2004,24(11):1251-1257
Somatic embryos of oak (Quercus robur L.) were matured on P24 media differing in gel strength (0.8, 0.9 and 1.0% (w/v) agar). Viscosity and osmotic potential (Psipi,medium) of the media were determined. Developing cotyledonary embryos were analyzed at maturity Stages I-III for water content, osmotic potential (Psipi,embryo) and concentrations of abscisic acid (ABA) and proline. Proliferation of embryogenic tissue, germination rates and the number of embryos formed were also determined in order to relate embryo quality to physiological parameters. Viscosity increased with agar concentration, a phenomenon apparently related to water availability. Many Stage III embryos with high germination potentials were obtained on P24 medium containing 1.0% agar. Embryo water content decreased progressively from 94 to 80% during embryo maturation. Stage I and II embryos that matured on media containing 0.8 or 0.9% agar had similar values of Psipi,embryo, whereas Psipi,embryo of Stage III embryos that matured on medium containing 1.0% agar was significantly lower, although Psipi,medium was unaffected by gel strength. Stage III embryos showed a nearly 16-fold increase in proline concentration and a 50% decrease in ABA concentration compared with Stage I embryos. We conclude that tissue water status and a complex relationship between ABA and proline concentrations, modulated by medium gel strength, are important factors in the maturation process and the quality of oak somatic embryos.  相似文献   
39.
40.
During the United States Department of Agriculture (USDA) National Animal Health Monitoring System’s (NAHMS) 2007–2008 beef study, 567 producers from 24 US States were offered the opportunity to collect fecal samples from weaned beef calves and have them evaluated for the presence of parasite eggs (Phase 1). Participating producers were provided with instructions and materials for sample collection. Up to 20 fresh fecal samples were collected from each of the 99 participating operations. Fresh fecal samples were submitted to one of 3 randomly assigned laboratories for evaluation. Upon arrival at the laboratories, all samples were processed for the enumeration of strongyle, Nematodirus, and Trichuris eggs using the modified Wisconsin technique. The presence or absence of coccidian oocysts and tapeworm eggs was also noted. In submissions where the strongyle eggs per gram exceeded 30, aliquots from 2 to 6 animals were pooled for DNA extraction. Extracted DNA was subjected to genus level polymerase chain reaction (PCR) identification for the presence of Ostertagia, Cooperia, Haemonchus, Oesophagostomum, and Trichostrongylus. In this study, 85.6% of the samples had strongyle type, Nematodirus, and Trichuris eggs. Among the samples evaluated, 91% had Cooperia, 79% Ostertagia, 53% Haemonchus, 38% Oesophagostomum, 18% Nematodirus, 7% Trichuris, and 3% Trichostrongylus. The prevalence of coccidia and tapeworm eggs was 59.9% and 13.7%, respectively.  相似文献   
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