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Life Sciences

University of Nebraska - Lincoln

2004

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Effect Of Age, Pregnancy, And Diet On Urinary Creatinine Excretion In Heifers And Cows, Kimberly M. Whittet, Terry J. Klopfenstein, Galen E. Erickson, Tim W. Loy, R. Allen Mcdonald Jan 2004

Effect Of Age, Pregnancy, And Diet On Urinary Creatinine Excretion In Heifers And Cows, Kimberly M. Whittet, Terry J. Klopfenstein, Galen E. Erickson, Tim W. Loy, R. Allen Mcdonald

Nebraska Beef Cattle Reports

A series of total urine collections was conducted to evaluate effect of age, pregnancy and diet on creatinine excretion in heifers and cows. To test effect of age on creatinine excretion, 31 animals ranging from 5 to 104 months of age were fed a hay diet supplemented with dried distillers grains (DDG). There was no difference in creatinine excretion across age. Cows fed the same diet were sampled to determine effect of pregnancy on creatinine excretion. Pregnancy did not affect daily creatinine excretion. Two collection periods were conducted to determine if diet alters creatinine excretion. In period 1, heifers were …

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Impact Of Cleaning Frequency On Nitrogen Balance In Open Feedlot Pens, Casey B. Wilson, Galen E. Erickson, Casey N. Macken, Terry J. Klopfenstein Jan 2004

Impact Of Cleaning Frequency On Nitrogen Balance In Open Feedlot Pens, Casey B. Wilson, Galen E. Erickson, Casey N. Macken, Terry J. Klopfenstein

Nebraska Beef Cattle Reports

Pen cleaning frequency of feedlot pens was evaluated during the summer of 2001 and 2002. Dry matter, organic matter and nitrogen recoveries were evaluated on a per head basis. Cleaning pens monthly compared to cleaning at the end of the feeding period resulted in significantly more DM, OM and N recovered. Cleaning pens every month increased N removal by 7.0 lb per steer (49.9% increase) above manure N removed at the end of the feeding period.

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Hexapod Herald - Vol. 16, No. 1, January 2004 Jan 2004

Hexapod Herald - Vol. 16, No. 1, January 2004

Hexapod Herald and Other Entomology Department Newsletters

Contents:
Congratulations
Welcome
Farewell
Faculty News
Grad Student News
From the Office
Grants
Museum News
Publications
Travel
Condolences
This & That

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Cardicola Forsteri (Digenea: Sanguinicolidae) From The Heart Of A Northern Bluefin Tuna, Thunnus Thynnus (Scombridae), In The Northwest Atlantic Ocean, Stephen A. Bullard, Robert J. Goldstein, Robert H. Goodwin Iii, Robin M. Overstreet Jan 2004

Cardicola Forsteri (Digenea: Sanguinicolidae) From The Heart Of A Northern Bluefin Tuna, Thunnus Thynnus (Scombridae), In The Northwest Atlantic Ocean, Stephen A. Bullard, Robert J. Goldstein, Robert H. Goodwin Iii, Robin M. Overstreet

Harold W. Manter Laboratory of Parasitology: Faculty and Staff Publications

We report a specimen of Cardicola forsteri Cribb, Daintith, and Munday, 2000 (Digenea: Sanguinicolidae) from the lumen of the heart of a northern bluefin tuna, Thunnus thynnus (Linnaeus, 1758) (Scombridae), that was 218 cm in total length (TL) and caught in the northwest Atlantic Ocean 12 km south of Cape Lookout, North Carolina. The hearts of 12 similarly sized northern bluefin tuna (127–262 cm TL) from George’s Bank, northwest Atlantic Ocean, were not infected. This is the first report of C. forsteri from a wild host and of a sanguinicolid from any scombrid in the northwest Atlantic Ocean. Bluefin tuna …

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Paneak's Plants And Animals [In A Hungry Country: Appendix 1], Robert L. Rausch Jan 2004

Paneak's Plants And Animals [In A Hungry Country: Appendix 1], Robert L. Rausch

Harold W. Manter Laboratory of Parasitology: Faculty and Staff Publications

A list of plants and animals recognized by Simon Paneak (1900-1975), a Nunamiut Eskimo. Names are given in English and Iñupiaq, and their scientific names are provided.

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Some Aspects Of The Biology And Life History Of Bothitrema Bothi (Monogenea: Bothitrematidae) From The Flounder Scophthalmus Aquosus (Bothidae) From New Jersey, Usa, Sherman S. Hendrix Jan 2004

Some Aspects Of The Biology And Life History Of Bothitrema Bothi (Monogenea: Bothitrematidae) From The Flounder Scophthalmus Aquosus (Bothidae) From New Jersey, Usa, Sherman S. Hendrix

Harold W. Manter Laboratory of Parasitology: Faculty and Staff Publications

Bothitrema bothi (MacCallum, 1913), a monopisthocotylean monogenean (Bothitrematidae) found on gills and occasionally on the olfactory rosette within the nares of the bothid flounder, Scophthalmus aquosus (Mitchill, 1815), is distributed along the Atlantic coast of the USA from Woods Hole, Massachusetts to Delaware Bay. This study details aspects of the morphology, microecology and biology of the oncomiracidium, juvenile and adult. Adult worms occur almost exclusively between rakers on the first and second gill arches while juveniles occupy secondary gill filaments. Analysis of variance revealed significant arch, side and position effects. Worm attachment and position is maintained largely by suction generated …

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Host–Symbiont Stability And Fast Evolutionary Rates In An Ant–Bacterium Association: Cospeciation Of Camponotus Species And Their Endosymbionts, Candidatus Blochmannia, Patrick H. Degnan, Adam B. Lazarus, Chad D. Brock, Jennifer J. Wernegreen Jan 2004

Host–Symbiont Stability And Fast Evolutionary Rates In An Ant–Bacterium Association: Cospeciation Of Camponotus Species And Their Endosymbionts, Candidatus Blochmannia, Patrick H. Degnan, Adam B. Lazarus, Chad D. Brock, Jennifer J. Wernegreen

School of Biological Sciences: Faculty Publications

Bacterial endosymbionts are widespread across several insect orders and are involved in interactions ranging from obligate mutualism to reproductive parasitism. Candidatus Blochmannia gen. nov. (Blochmannia) is an obligate bacterial associate of Camponotus and related ant genera (Hymenoptera: Formicidae). The occurrence of Blochmannia in all Camponotus species sampled from field populations and its maternal transmission to host offspring suggest that this bacterium is engaged in a long-term, stable association with its ant hosts. However, evidence for cospeciation in this system is equivocal because previous phylogenetic studies were based on limited gene sampling, lacked statistical analysis of congruence, and have …

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Isolation And Characterization Of 11 Polymorphic Microsatellite Loci In Collared Lizards (Crotaphytus Collaris), Delbert W. Hutchison, Jared L. Strasburg, Jennifer A. Brisson, Shawn Cummings Jan 2004

Isolation And Characterization Of 11 Polymorphic Microsatellite Loci In Collared Lizards (Crotaphytus Collaris), Delbert W. Hutchison, Jared L. Strasburg, Jennifer A. Brisson, Shawn Cummings

School of Biological Sciences: Faculty Publications

We identified 11 polymorphic microsatellite loci in collared lizards (Crotaphytus collaris). Polymorphism assessment in 512 individuals from 52 populations sampled across much of the species distribution revealed a fairly high degree of genetic diversity (six to 20 alleles per locus) and a wide range of average expected heterozygosity values (0.143–0.530). We found no evidence for linkage, very few deviations from HW expectation (two of 572 possible population/locus analyses) and thus no evidence for null alleles. There was a tendency for reduced polymorphism towards the northern periphery.

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Do Harvest Refuges Buffer Kangaroos Against Evolutionary Responses To Selective Harvesting?, Brigitte Tenhumberg, Andrew J. Tyre, Anthony R. Pople, Hugh P. Possingham Jan 2004

Do Harvest Refuges Buffer Kangaroos Against Evolutionary Responses To Selective Harvesting?, Brigitte Tenhumberg, Andrew J. Tyre, Anthony R. Pople, Hugh P. Possingham

School of Biological Sciences: Faculty Publications

There is a wealth of literature documenting a directional change of body size in heavily harvested populations. Most of this work concentrates on aquatic systems, but terrestrial populations are equally at risk. This paper explores the capacity of harvest refuges to counteract potential effects of size-selective harvesting on the allele frequency of populations. We constructed a stochastic, individual-based model parameterized with data on red kangaroos. Because we do not know which part of individual growth would change in the course of natural selection, we explored the effects of two alternative models of individual growth in which alleles affect either the …

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Linking Wild And Captive Populations To Maximize Species Persistence: Optimal Translocation Strategies, Brigitte Tenhumberg, Andrew J. Tyre, Katriona Shea, Hugh P. Possingham Jan 2004

Linking Wild And Captive Populations To Maximize Species Persistence: Optimal Translocation Strategies, Brigitte Tenhumberg, Andrew J. Tyre, Katriona Shea, Hugh P. Possingham

School of Biological Sciences: Faculty Publications

Captive breeding of animals is widely used to manage endangered species, frequently with the ambition of future reintroduction into the wild. Because this conservation measure is very expensive, we need to optimize decisions, such as when to capture wild animals or release captive-bred individuals into the wild. It is unlikely that one particular strategy will always work best; instead, we expect the best decision to depend on the number of individuals in the wild and in captivity. We constructed a first-order Markov-chain population model for two populations, one captive and one wild, and we used stochastic dynamic programming to identify …

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Genetic Discontinuities Among Populations Of Cleistes (Orchidaceae, Vanilloideae) In North America, Stacey Dewitt Smith, Robyn S. Cowan, Katharine B. Gregg, Mark W. Chase, Nigel Maxted, Michael F. Fay Jan 2004

Genetic Discontinuities Among Populations Of Cleistes (Orchidaceae, Vanilloideae) In North America, Stacey Dewitt Smith, Robyn S. Cowan, Katharine B. Gregg, Mark W. Chase, Nigel Maxted, Michael F. Fay

School of Biological Sciences: Faculty Publications

Genetic patterns were examined in five populations of North American Cleistes with three sources of molecular data: amplified fragment length polymorphisms (AFLP), DNA sequencing, and plastid microsatellites. Populations of C. bifaria were sampled in four areas of the south-eastern US: the coastal plains of Florida and North Carolina and the mountains of North Carolina and West Virginia. A population of C. divaricata sympatric with the North Carolina coastal plain C. bifaria was also sampled. Analysis of the three types of molecular data resulted in the same relationships among the five sampled populations. The coastal plain population of C. divaricata was …

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The Role Of Local Spatial Heterogeneity In The Maintenance Of Parapatric Boundaries: Agent Based Models Of Competition Between Two Parasitic Ticks, Andrew J. Tyre, Brigitte Tenhumberg, C. Michael Bull Jan 2004

The Role Of Local Spatial Heterogeneity In The Maintenance Of Parapatric Boundaries: Agent Based Models Of Competition Between Two Parasitic Ticks, Andrew J. Tyre, Brigitte Tenhumberg, C. Michael Bull

School of Biological Sciences: Faculty Publications

Recent models of ecological parapatry, where the geographical distributions of two similar species abut without overlapping, have shown that spatial gradients in intrinsic growth rates can lead to sharp boundaries when dispersal is density dependent. However, a well documented parapatric boundary in southern Australia between two tick species that parasitise a large lizard lacks one or both of these features; dispersal of ticks is random and there may not be a gradient of population growth rates for one of the species. There is local variation in population growth rates arising from variation in the number of host lizards with overlapping …

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Long-Range Visibility Of Greater Sage Grouse Leks: A Gis-Based Analysis, Andrea S. Aspbury, Robert M. Gibson Jan 2004

Long-Range Visibility Of Greater Sage Grouse Leks: A Gis-Based Analysis, Andrea S. Aspbury, Robert M. Gibson

School of Biological Sciences: Faculty Publications

We investigated whether male greater sage grouse, Centrocercus urophasianus, select lek locations on the basis of topographic features that affect their visibility to both conspecific females and a major avian predator, the golden eagle, Aquila chrysaetos. We mapped locations of displaying males at all leks in a local population and used a Geographic Information System (GIS) and digital elevation model (DEM) to generate ‘viewsheds’ around male locations within a boundary set by the estimated maximal visual acuity of the viewer. Areas visible around leks were compared to those visible around random sites with the same conformation of displaying …

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2004 Annual Report: Migratory Bird Conservation Commission Jan 2004

2004 Annual Report: Migratory Bird Conservation Commission

United States Fish and Wildlife: Staff Publications

Report of the Migratory Bird Conservation Commission for the Fiscal Year 2004

Approvals During Fiscal Year 2004

Migratory Bird Conservation Fund

Summary of Fiscal Year 2004 MBCF Land Acquisitions

New National Wildlife Refuge Boundary Approvals

Membership of the Migratory Bird Conservation Commission

Map Showing National Migratory Bird Refuge Areas

Map Showing Wetland Management Districts

Notes on Tables One and Two

Table One – National Migratory Bird Refuge Areas

Table Two – Waterfowl Production Areas by State and County

North American Wetlands Conservation Fund

Table Three – U.S. Wetland Conservation Proposals Approved by the Migratory Bird Conservation Commission for FY 2004 …

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Environmental Contaminants Associated With A Swine Concentrated Animal Feeding Operation And Implications For Mcmurtrey National Wildlife Refuge, Matthew S. Schwarz, Kathy R. Echols, Mark J. Wolcott, Karen J. Nelson Jan 2004

Environmental Contaminants Associated With A Swine Concentrated Animal Feeding Operation And Implications For Mcmurtrey National Wildlife Refuge, Matthew S. Schwarz, Kathy R. Echols, Mark J. Wolcott, Karen J. Nelson

United States Fish and Wildlife: Staff Publications

Waste generated by concentrated animal feeding operations (CAFOs) may contain a variety of contaminants including nutrients, pathogens, trace elements, antibiotics, and hormones. In 2000, the U.S. Fish and Wildlife Service began to characterize CAFO contaminants in lagoons, canals, and created wetlands operated by Hastings Pork, a large swine CAFO adjacent to McMurtrey National Wildlife Refuge (McMurtrey) in Clay County, Nebraska. The created wetlands were designed to attract waterfowl; therefore, the primary purpose of this research was to evaluate whether migratory waterfowl were likely exposed to CAFO contaminants. A secondary research objective was to determine if created wetland water was suitable …

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