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91.
Tame mule deer and elk were fed fresh alfalfa hay at night and given various alternate forages during the day. This schedule, simulating farmland depredation feeding, yielded consumption values for field-growing alfalfa hay. 相似文献
92.
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Diel activity and association patterns of white bass ( Morone chrysops ) and carp ( Cyprinus carpio ) in Utah Lake, Utah, were studied over four 24-hr periods during August 1980. Fish were concurrently sampled from two adjacent littoral habitats. Significant differences existed in diel activity patterns in two of three size classes of white bass and in diel association patterns of white bass and carp between the two habitat areas. Differences in habitat structure, and in biological activity between the habitat types, are implicated as the primary determinants of overall diel activity of fish in these littoral areas. 相似文献
93.
During the summers of 1982, 1983, and 1984, 269 sheep dogs from an area endemic for hydatid disease were examined for cestodes ( Echinococcus granulosus and Taenia spp.). Each dog was given an oral purge of arecoline hydrobromide and then following purgation received a subcutaneous injection of praziquantel (Droncit ® ). During the three-year study period, 205 dogs were examined one time only, 48 dogs were examined two of the three years, and 16 dogs were examined each of the three years (= 349 separate examinations). In 1982, 45 of 91 dogs examined (49.5%) harbored at least one species of cestode. Those data for 1983 and 1984 were 55 positive of 141 examined (39.0%) and 34 positive of 117 examined (29.1%), respectively. The marked drop in dogs infected during the second and third year of the study suggests that many sheep ranchers were implementing some of the control measures recommended for prevention of E. granulosus infections. The numbers of separate purgations showing specific cestodes detected in all positive dogs (some dogs naturally with more than one species of cestode) were: E. granulosus, 16 (4.6%); T. hydatigena, 34 (9.7%); T. ovis krabbei, 46 (13.2%); T. pisiformis, 47 (13.5%); and T. serialis, 24 (6.9%). 相似文献
94.
Inland populations of cutthroat trout have suffered dramatic declines and some subspecies are considered threatened or endangered. Understanding patterns of variation and factors that influence life history in populations is important for conservation and management. We determined effects of elevation, sex, and genetic introgression (with Yellowstone cutthroat trout, Oncorhynchus clarkii lewisi , and rainbow trout, Oncorhynchus mykiss ) on growth rates of Colorado River cutthroat trout ( Oncorhynchus clarkii pleuriticus ) in the Sheep Creek drainage in the Uinta Mountains of Utah. In this high-elevation system, native trout grew slowly and matured relatively late. Elevation, sex, and genetic introgression all had significant effects on growth rates. Growth rates were lower at higher elevations. Males were slightly larger than females, and cutthroat trout in locations that were more introgressed grew faster than those at nonintrogressed locations. Both abiotic effects and effects of introduced salmonids must be addressed in long-term management programs to ensure the sustainability of native trout populations. 相似文献
95.
Eric J. Billman Jared B. Lee D. Owen Young Matthew D. McKell R. Paul Evans Dennis K. Shiozawa 《西北部美国博物学家》2011,70(1)
Historical events have had a great impact on the biogeography of fishes of western North America. We examined the genetic variation of the speckled dace ( Rhinichthys osculus ) to determine the effects on this species of extensive hydrological changes during the last 10 million years in the Bonneville and Lahontan basins of the Great Basin and the upper Snake River Basin. Eight hundred sixty-nine base pairs of the mitochondrial gene cytochrome b were sequenced from 97 individuals representing 22 populations within these 3 basins, as well as from 2 individuals of longnose dace ( Rhinichthys cataractae ) that served as outgroups. Additionally, 13 speckled dace sequences representing 3 Bonneville populations were used from GenBank. Phylogenetic relationships were reconstructed using maximum parsimony and maximum likelihood criteria. Analysis of molecular variance was used to determine population structure and to estimate the amount of gene flow across the community boundaries. Three distinct clades were reconstructed representing the Lahontan Basin, the northern Bonneville and upper Snake River basins, and the southern Bonneville Basin. Additionally, most of the population structuring was explained by variation among basins (65.33%). Speckled dace demonstrated high genetic variation. As hypothesized, the northern and southern Bonneville specimens formed separate clades; however, the southern Bonneville clade was basal to a sister clade formed by the northern Bonneville/upper Snake River and Lahontan clades. These relationships indicate that Pliocene connections between the Snake, Lahontan, and Bonneville drainages, rather than more recent Pleistocene connections, best explain population structuring in speckled dace. 相似文献
96.
Studies of Great Basin faunas can provide information for landscape-level adaptive management by federal agencies and shed light on potential effects of climate change in continental interior landscapes. To provide such information, we characterized the butterfly fauna of the Toquima Range, a mountain range in the heart of the Great Basin with topography typical of the region. We also compared the butterfly fauna of the Toquima Range to that of the adjacent Toiyabe Range, which is more topographically complex and species rich but less representative of the Great Basin on the whole. We explicitly addressed the effects of area and water availability on butterfly species richness. Butterfly species presence data were compiled for 14 canons and 1 peak in the Toquima Range. Data from 11 canyons that we inventoried systematically were amenable to statistical analysis. Eighty butterfly species (59 residents) have been recorded from the Toquima Range since 1935. By comparison, 99 species have been recorded from the Toiyabe Range. Mean canyon-level butterfly species richness was significantly lower in the Toquima Range than in the Toiyabe Range. This difference cannot be explained by differences in canyon size between mountain ranges. Within the Toquima Range water availability seems to have a dominant effect on butterfly species richness. Between mountain ranges species richness is influenced by interactions among areas, moisture, and topography. These data should assist managers in developing guidelines for conservation planning in the Great Basin. 相似文献
97.
Dennis D. Austin 《西北部美国博物学家》2011,60(2)
History and technical literature describing potential effects of livestock grazing on mule deer ( Odocoileus hemionus ) populations and winter range habitat are reviewed. Recommendations for livestock grazing on winter ranges within the Great Basin are advanced. 相似文献
98.
Dennis D. Austin Robert A. Riggs Philip J. Urness David L. Turner John F. Kimball 《西北部美国博物学家》2011,49(1)
Trends in age-specific, eviscerated carcass weights were determined for hunter-harvested yearling and two-year-old buck mule deer. Carcass weights declined over an 11-year period from two areas of similar management, but with independenly collected data sets. Carcass weights also declined between the opening and second weekends of the hunt. Management implications are discussed. 相似文献
99.
A new active metabolite of "Miracil D" 总被引:2,自引:0,他引:2
100.
Humans are colonized by multitudes of commensal organisms representing members of five of the six kingdoms of life; however, our gastrointestinal tract provides residence to both beneficial and potentially pathogenic microorganisms. Imbalances in the composition of the bacterial microbiota, known as dysbiosis, are postulated to be a major factor in human disorders such as inflammatory bowel disease. We report here that the prominent human symbiont Bacteroides fragilis protects animals from experimental colitis induced by Helicobacter hepaticus, a commensal bacterium with pathogenic potential. This beneficial activity requires a single microbial molecule (polysaccharide A, PSA). In animals harbouring B. fragilis not expressing PSA, H. hepaticus colonization leads to disease and pro-inflammatory cytokine production in colonic tissues. Purified PSA administered to animals is required to suppress pro-inflammatory interleukin-17 production by intestinal immune cells and also inhibits in vitro reactions in cell cultures. Furthermore, PSA protects from inflammatory disease through a functional requirement for interleukin-10-producing CD4+ T cells. These results show that molecules of the bacterial microbiota can mediate the critical balance between health and disease. Harnessing the immunomodulatory capacity of symbiosis factors such as PSA might potentially provide therapeutics for human inflammatory disorders on the basis of entirely novel biological principles. 相似文献