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81.
Nonhuman animals in captivity can experience environmental privation that results in their exhibiting abnormal behaviors. Environmental enrichment techniques can help improve their welfare. This study investigated the behavior of 8 zoo-housed oncilla cats (Leopardus tigrinus) in response to 2 odors (catnip and cinnamon) introduced individually into the animals' enclosures for 3 consecutive days. Proportion of scans spent engaging in stereotypical pacing were compared before, during, and after treatments. The addition of cinnamon reduced the proportion of pacing during and after enrichment (Wilcoxon: Z = 3.16, p < .001; Z = 3.16, p < .001, respectively), indicating a prolonged effect of the enrichment on the animals' behavior. Catnip appears to have elicited no significant difference in the stereotypic pacing before, during, or after the enrichment (Friedman: X(2) = 2.69; p = .260). The results highlight the potential use of cinnamon as a method of environmental enrichment for small captive-housed cats.  相似文献   
82.
Allelic frequencies and other population data analysis are reported for the 15 autosomal Short Tandem Repeats (STR) loci included in the PowerPlex®16 kit (CSF1PO, D13S317, D16S539, D18S51, D21S11, D3S1358, D5S818, D7S820, D8S1179, FGA, Penta D, Penta E, TPOX, TH01 and vWA) in Pomeranian’s descendants from the Espirito Santo State (ES), Brazil, third largest population of Pomeranian’s descendants in the world. They chose the mountain region of the state for their preferred geographic location, and they have a very peculiar lifestyle with a selective mating behavior which has maintained their characteristics as a relatively pure subpopulation. Blood samples were obtained from 82 unrelated volunteers from 11 different cities of Espirito Santo State, where there are the Pomeranian’s descendants. All 15 loci analyzed showed Power of Discrimination (PD) values > 0.75. Except the TPOX locus, all analyzed loci were at Hardy–Weinberg equilibrium. This subpopulation has not yet been characterized for STR allelic frequencies used for forensic and genetic identification studies.  相似文献   
83.
Yeast population used in industrial production of fuel-ethanol may vary according to the plant process condition and to the environmental stresses imposed to yeast cells. Therefore, yeast strains isolated from a particular industrial process may be adapted to such conditions and should be used as starter strain instead of less adapted commercial strains. This work reports the use of PCR-fingerprinting method based on microsatellite primer (GTG)5 to characterize the yeast population dynamics along the fermentation period in six distilleries. The results show that indigenous fermenting strains present in the crude substrate can be more adapted to the industrial process than commercial strains. We also identified new strains that dominate the yeast population and were more present either in molasses or sugar cane fermenting distilleries. Those strains were proposed to be used as starters in those industrial processes. This is the first report on the use of molecular markers to discriminate Saccharomyces cerevisiae strains from fuel-ethanol producing process.  相似文献   
84.
Ceratocystis wilt caused by the fungus Ceratocystis fimbriata, is currently one of the major diseases in commercial plantations of Eucalyptus trees in Brazil. Deployment of resistant genotypes has been the main strategy for effective disease management. The present study aimed at identifying genomic regions underlying the genetic control of resistance to Ceratocystis wilt in Eucalyptus by quantitative trait loci (QTL) mapping in an outbred hybrid progeny derived from a cross between (Eucalyptus dunnii × Eucalyptus grandis) × (Eucalyptus urophylla × Eucalyptus globulus). A segregating population of 127 individuals was phenotyped for resistance to Ceratocystis wilt using controlled inoculation under a completely randomized design with five clonal replicates per individual plant. The phenotypic resistance response followed a continuous variation, enabling us to analyze the trait in a quantitative manner. The population was genotyped with 114 microsatellite markers and 110 were mapped with an average interval of 12.3 cM. Using a sib-pair interval-mapping approach five QTLs were identified for disease resistance, located on linkage groups 1, 3, 5, 8, and 10, and their estimated individual heritability ranged from 0.096 to 0.342. The QTL on linkage group 3 overlaps with other fungal disease-resistance QTLs mapped earlier and is consistent with the annotation of several disease-resistance genes on this chromosome in the E. grandis genome. This is the first study to identify and attempt to quantify the effects of QTLs associated with resistance to Ceratocystis wilt in Eucalyptus.  相似文献   
85.
The signal produced by fluorescence in situ hybridization (FISH) often is inconsistent among cells and sensitivity is low. Small DNA targets on the chromatin are difficult to detect. We report here an improved nick translation procedure for Texas red and Alexa Fluor 488 direct labeling of FISH probes. Brighter probes can be obtained by adding excess DNA polymerase I. Using such probes, a 30 kb yeast transgene, and the rp1, rp3 and zein multigene clusters were clearly detected.  相似文献   
86.
Sorghum [Sorghum bicolor (L.) Moench] is a multipurpose grass cultivated in drylands due to its adaptation to drought. However the characteristics of sorghum-associated bacteria are not known in the Brazilian drylands. The aim of this study was to isolate and evaluate the plant growth promotion potential bacteria from field-grown sorghum under two irrigation and manure application levels in a Brazilian semi-arid reagion. Sorghum was irrigated with 3 or 1 mm day?1 and fertilized or not with liquid goat manure. Bacteria were obtained from surface-disinfected roots applying two nitrogen-free semi-solid media. The bacteria were evaluated for the presence of nifH gene, 16S rRNA sequences, calcium-phosphate solubilization, production of auxins and siderophores and for sorghum growth promotion. We obtained 20 out of 24 positive bacteria for nifH. The isolates were classified as in six different genera. All isolates produced auxins “in vitro”, six bacteria produced siderophores and three Enterobacteriaceae solubilized calcium-phosphate. At least ten bacteria resulted in the increased total N content in the sorghum shoots, comparable to fertilization with 50 mg N plant?1 week?1 and to inoculation with Azospirillum brasilense Ab-V5. Enterobacter sp. ESA 57 was the best sorghum plant-growth promoting bacteria isolated in this study.  相似文献   
87.
The endemic New Zealand ground wētā (Hemiandrus sp. ‘promontorius’) has a Naturally Uncommon conservation status. This is because of the paucity of information on its density and distribution. Here, the biology, density and distribution of a population of this wētā found in and around vineyards in the Awatere Valley, Marlborough was studied. Wētā density was assessed in vineyards, paddocks and shrublands in this valley. Soil moisture, penetration resistance, pH and organic matter were recorded at locations with and without wētā. Wētā density in vineyards was significantly higher than in either paddocks or shrub habitats. In vineyards, the density of this insect was significantly higher under-vines than in the inter-rows. Higher numbers of this wētā were found in moist soils that required lower force to burrow. Females laid an average of 55 eggs between March and April, which hatched in September. These findings highlight the intersection between agriculture and conservation.  相似文献   
88.
An Ustilago maydis ergosterol biosynthesis mutant (A14) which is partially blocked in sterol 14alpha-demethylase (P45014DM) activity is described. This mutant accumulated the abnormal 14alpha-methyl sterols, eburicol, 14alpha-methylfecosterol, and obtusifoliol, along with significant amounts of ergosterol. Although the A14 mutant grew nearly as well as the wild type, it was impaired in cell extension growth, which indicated a dysfunction in apical cell wall synthesis. The mutant was also found to be hypersensitive to the azole fungicides penconazole and tebuconazole.  相似文献   
89.
90.
Genera of the Cephennomicrus group of the Cephenniini (Scydmaenitae) are revised, and the following new taxa are described: Trichokrater gen.n. , Trichokrater ekkentros sp.n. (type species of Trichokrater) (Borneo), Cephennococcus gen.n. , Cephennococcus kuchingensis sp.n. (type species of Cephennococcus) (Borneo), Cephennococcus kenyirensis sp.n. (West Malaysia), Cephennococcus crassus sp.n. (Borneo), Cephennococcus minutissimus sp.n. (West Malaysia), Pomphopsilla gen.n. , Pomphopsilla luhya sp.n. (type species of Pomphopsilla) (Kenya) and Pomphopsilla soror sp.n. (Kenya). Unique subcuticular pockets with setose openings on the pronotum of Trurlia and Trichokrater are identified as glandular structures. Enigmatic internal prothoracic cavities are described for the first time in Scydmaeninae (in Cephennococcus, Pomphopsilla and a female of an undescribed genus from Sulawesi); their fine structure and function remain unknown. Parsimony‐based cladistic analysis of the adult morphology of genera of Cephenniini provided robust evidence for a monophyly of the Cephennomicrus group, composed of Cephennomicrus, Cephennula, Lathomicrus, Pomphopsilla, Cephennococcus, Trurlia, Trichokrater and two undescribed Oriental genera known from females only; this distinct and well‐supported lineage is a sister group of Cephennodes + Hlavaciellus. The genus Cephennomicrus represented in the analysis by species belonging to three previously postulated species groups is not monophyletic, and a comprehensive study comprising more taxa is necessary to reclassify this heterogeneous group.  相似文献   
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