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M D Kock R K Clark C E Franti D A Jessup J D Wehausen 《Journal of wildlife diseases》1987,23(4):652-662
Blood samples and physiological data were collected from 634 bighorn sheep (Ovis canadensis) captured by four different methods between 1980 and 1986 in the western United States. These parameters were evaluated for selected physiological, biochemical and hematological values. Postcapture biological parameters were compared among bighorn sheep according to four different outcomes; normal, stressed or compromised, capture myopathy (CM) mortality, and accidental mortality. Significant differences (P less than 0.05) were noted between outcome groups relative to certain parameters: temperature, respiration, creatinine phosphokinase (CPK), lactic dehydrogenase (LDH), serum glutamic oxaloacetic transaminase (SGOT), blood urea nitrogen (BUN), glucose, white blood cell count (WBC) and plasma pH. Such differences between groups may help in evaluating the clinical status of bighorn sheep at capture, enabling one to predict those animals that might develop CM at a later date, indicate candidates for preventive medical treatment prior to release, and/or which should be followed closely to determine long-term survival. Evaluation of follow-up data (n = 77) related to outcome status and long-term survival of bighorn sheep indicated that less than 4% (3 of 77) were dead within 1 mo of capture (one of these had been classified as normal and two as stressed or compromised at capture); less than 3% (3 of 77) were dead greater than 1 mo, and less than 6 mo after capture two were classified in the stressed outcome and one as diseased. Eighty-eight percent (68 of 77) were alive from 1 mo to 5 yr after capture (53 were classified as normal, 12 as stressed or compromised and 3 as diseased), and 2% (1 of 77) had chronic CM but was still alive (this animal had been classified as normal). Of 77 sheep in the follow-up group, less than 3% (2 of 77) were not observed following capture (one was classified as normal and one as stressed and diseased). Of the fatalities, less than 3% (2 of 40) had been captured by the net-gun and less than 4% (1 of 27) by drive-net. Those two unobserved in the follow-up group also had been caught with the net-gun, 5% (2 of 40). The single surviving CM case had been captured by the net-gun. Although the net-gun appears to be one of the safest methods of capturing individual bighorn sheep, based on evaluation of capture data and biological parameters, it may not be associated with the best long-term survival in some bighorn sheep.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
3.
We studied variation at 25 to 31 allozymic loci in African and Asian rhinoceroses. Four taxa in three genera were examined: African Ceratotherium simum simum (northern white rhinoceros), C. s. cottoni (southern white rhinoceros), Diceros bicornis (black rhinoceros), and Rhinoceros unicornis (Indian rhinoceros). Extremely small amounts of intraspecific variation were observed in sample sizes of 2 to 10 presumably unrelated individuals per taxon: P = .00-.10, H = 0.00-0.02. We examined demographic bottlenecks and sampling errors as possible reasons for the low levels of detectable variation. The very small intraspecific genetic distance (D = 0.005) between the two living white rhinoceros subspecies is far less than the distance that has been reported for other mammal subspecies. The mean D value of 0.32 +/- 0.11 between the two African genera was also less than expected given the divergence time of greater than 7 million years suggested by the fossil record. Rhinoceroses may be evolving more slowly at the structural gene loci than are some other mammal groups. The estimate of D = 1.05 +/- 0.24 for the African-Indian split supports this idea, as the lineage diverged at least 26 million years ago. Our results contribute to the currently available scientific information on which management decisions aimed toward saving endangered rhinoceroses should be based. 相似文献
4.
Using radioimmunoassay, blood platelet aggregation studies and GC-MS the existence of prostaglandins in the endomycetalean yeastDipodascopsis uninucleata was confirmed by our group. These findings triggered the search for similar eicosanoids in the rest of the Endomycetales. We commenced by scanning for the easily detectable precursors of eicosanoids, linoleic- and linolenic acid. We selected two families (i.e. Lipomycetaceae and Dipodascaceae), both producing these precursors, for further investigation.Representative strains of the two families were tested for their ability to grow in the presence of 1mM aspirin, a specific inhibitor of prostaglandin biosynthesis. In contrast to the lipomycetaceous species the dipodascaceous species were insensitive to this drug. These results were verified when representative strains of both families were investigated for their ability to produce eicosanoids from externally fed radio-labeled arachidonic acid along an aspirin sensitive pathway. Thin layer chromatography of culture extracts, followed by autoradiography, showed that while none of the Dipodascaceae produced aspirin sensitive arachidonic acid metabolites, the members of the Lipomycetaceae tested positive for these metabolites. These findings supported the separation of the lipomycetaceous yeastDipodascopsis from the Dipodascaceae. The findings also correlate with the delimitation of these yeasts in two families (i.e. Dipodascaceae and Lipomycetaceae).Further investigation indicated that prostaglandin production by the genusDipodascopsis is mainly associated with ascosporogenesis. Thin layer chromatography of cell extracts fromDipodascopsis tóthii, followed by scintillation counting, indicated the presence of PGF2 and PGE2 during ascosporogenesis. 相似文献
5.
The taxonomic importance of fatty acid composition at genus and sub-genus level was evaluated by analysing the fatty acid
composition of fourteen different Microcystis isolates and seven additional members of the order Chroococcales. Fatty acid composition proved to be consistent within isolates.
Isolates were clustered into two major groups, namely A and B. Group B contained all the Microcystis isolates and was further divided into subgroups of varying similarity indicating the existence of different taxa. The Microcystis isolates were characterised by a high content of polyunsaturated fatty acids (27–44%) and a low content of palmitoleate.
The test organisms were arranged in a scheme indicating their possible phylogenetic relationship based on fatty acid composition
and other phenotypic characteristics. According to our data the toxic strains, represented by different isolates, of Microcystis appear as a distinct group. Furthermore two dubious species namely Microcystis incerta and a Synechocystis sp. could clearly be reasigned to different genera. The results demonstrated that fatty acid composition is an effective
taxonomic tool in clarifying taxonomical problems of Microcystis isolates.
Department of Microbiology, University of the Orange Free State 相似文献
6.
J. C. du Preez M. Immelman J. L. F. Kock S. G. Kilian 《World journal of microbiology & biotechnology》1997,13(1):81-87
The effect of different initial acetic acid concentrations on the growth of and lipid and gamma-linolenic acid (GLA) production
byMucor circinelloides CBS 203.28 was determined in a 14 litre stirred tank reactor operated in a fedbatch, pH-stat mode with acetic acid as carbon
source and pH titrant. Increased acetic acid concentrations in the culture resulted in a significant increase in the crude
oil content of the biomass. By contrast, all the other parameters such as the biomass concentration, GLA and oil yield on
acetic acid, the GLA content of the biomass and oil, the growth rate and volumetric rate of GLA production decreased with
an increase in acetic acid concentration. The best results were obtained with acetic acid at 2 g/1, which gave 39.8 mg GLA/g
biomass and 15.6% GLA in the neutral lipid fraction, amounting to 340 mg GLA/1 culture. A decrease in the glyco- and phospho-lipid
fractions during the cultivation coincided with an increase in the neutral lipid fraction. The GLA content of the biomass
remained within rather narrow limits of 3.5% to 4% of the biomass, irrespective of the oil content of the biomass. The fatty
acid profile was not greatly affected by the acetic acid concentration. The hyphae of the fungus were characterized by the
accumulation of large intracellular oil droplets and some septa delimited the hyphae. 相似文献
7.
8.
T.J. BRITZ AND K-H.J. RIEDEL. 1991. Phenotypic results from 81 tests conducted on 73 propionibacteria, including five type strains, 22 reference strains, unidentified propionibacteria and strains isolated from dairy sources, were analysed by numerical taxonomy. Characters giving uniform results were excluded. With the simple matching coefficient and the single linkage cluster analysis, 61 cultures were recovered in five major clusters. Final linkage of all the Propionibacterium cultures examined was at the 77% S-level. The results clearly showed that it was possible to distinguish between the 'classical' and 'cutaneous' Propionibacterium spp., corresponding with the type habitat of each group. The major 'classical' clusters were equated with the P. freudenreichii, P. thoenii, P. jensenii and P. acidipropionici species, while the only major 'cutaneous' cluster was equated with the P. acnes species. The major clusters were identified by relating them to specific type strains and by comparing phenotypic characteristics. The differentiating characteristics of each cluster were determined. The largest cluster, representing 37% of the strains, was equated with P. jensenii but contained cultures that produced an atypical brown/red pigment. These strains, although positively identified as P. jensenii , could also be identified as the 'old' P. rubrum ' species. Thus if pigmentation is used as differential characteristic two distinct groups of propionibacteria could be identified within the P. jensenii species. 相似文献
9.
Robert K Logan Kock 《Environmental Biology of Fishes》1982,7(2):121-136
Synopsis Development of the fish community on a submerged 16 m barge and variation in fish abundance on nearby transects were surveyed twice monthly for twenty months. A steady increase in abundance was observed for certain fishes on the barge, whereas a few species exhibited distinct seasonal variation on both the barge and transects. Most of the seasonal species settled between March and May.Some seasonal species appeared to be site selective in their settlement and consequently settled juveniles were clumped in their distribution. An abundance of preferred topographical features may be why settlement was relatively high at the study site and indirectly why predators became significantly (r3 = 7.67***, N = 37) more abundant at the study area during the months of maximum prey settlement. Concurrent settlement of several species during the same few months may be important because juveniles become an abundant food source to predators during those few months only. Periodic swamping of predators by abundant juvenile prey may improve the chances for individuals of rarer prey species to be overlooked and therefore be succesfully recruited. 相似文献
10.
The long-chain fatty acid compositions of 22 species of Candida were determined, and compared with the fatty acid compositions of 10 species of the genus Pichia that contain coenzyme Q9. The long-chain fatty acid results were also compared with other phenotypic criteria (i.e. assimilation of carbon sources, coenzyme Q type, G + C content and proton magnetic resonance spectra) in order to establish possible anamorph/teleomorph relations. Close correlations were found between known perfect/imperfect states. The results suggest that C. cacaoi and P. farinosa, and C. maltosa and P. etchellsii, also have anamorph/teleomorph relationships. 相似文献