Digital Commons Network^™

Testosterone Influences On Growth, Performance, Carcass Characteristics And Composition Of Young Market Lambs, B. D. Schanbacher, J. D. Crouse, C. L. Ferrell

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Ram lambs, wethers and wethers implanted with Silastic capsules containing crystalline testerone were placed on test at 14.9 ± 1.1 kg and evaluated for differences in growth, performance, carcass characteristics and composition. Silastic implants that were able to maintain physiological concentrations of serum testosterone provided appropriate replacement therapy in wethers. Growth rate, efficiency of feed utilization and carcass yield of intact ram lambs and testosterone-implanted wethers were superior to the corresponding traits of wethers. Wethers had greater backfat thickness and percentage kidney and pelvic fat, and their carcasses graded higher than those of ram lambs or wethers implanted with a …

Testosterone Regulation Of Luteinizing Hormone And Follicle Stimulating Hormone Secretion In Young Male Lambs, B. D. Schanbacher

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Polydimethylsiloxane (Silastic) capsules containing crystalline testosterone were implanted subcutaneously in castrate lambs and evaluated for their ability to (1) provide stable, physiological concentrations of serum testosterone and (2) regulate secretion of LH and FSH. Testosterone was nondectable (<.2 ng/ml) between 12 and 24 weeks of age in the serum of castrate lambs implanted with empty capsules but was increased at those ages in Iambs implanted with 20 cm (1.2 ± .1 and .5 ± .1 ng/ml), 60 cm (2.8 ± .1 and .9 ± .1 ng/ml) and 180 cm (6.6 ± .3 and 1.9 ± .2 ng/ml) of testosterone-filled Silastic tubing. Serum concentrations of LH and FSH were suppressed by exogenous testosterone and did not exceed concentrations in intact control rams as long as serum testosterone concentrations were greater than 1 ng/ml. In conclusion, simultaneous suppression of serum LH and FSH by concentrations of testosterone that cause a dose-dependent stimulatory effect on accessory sex gland weights indicates that testosterone is a physiological regulator of gonadotropin secretion in ram lambs. Although testosterone per se may not be directly responsible for negative feedback on LH and FSH secretion, the results presented herein question the need for a nonsteroidal "inhibin-like" testicular hormone to regulate FSH in lambs.

Androgen Response Of Cryptorchid And Intact Rams To Ovine Lh, B. D. Schanbacher

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Surgically induced cryptorchidism in rams resulted in elevated serum concentrations of LH but near-normal concentrations of androgen (testosterone and 5α-DHT).Injections of ovine LH (2 × 50μg;2 × 500 μg)resulted in maximal androgen secretion in the intact rams and similar but lower concentrations in cryptorchid rams. Peak concentrations were 14·9and 8·5ng/ml in the intact and cryptorchid rams respectively (P < 0·05).

Investigations Of Ryegrass Toxicity, B A. Stynes

Experimental Summaries - Plant Research

Shedding of galls in pasture - 79KA11. Development of toxicity in the field - 80KA25, 80MO39, 80NA34. Effect of herbicide on gall development - 80KA26.

Arapaho Prairie, Arthur County, Nebraska: Approximate Ap Grid For Gis, Kathleen H. Keeler, A. T. Harrison, L. S. Vescio

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Grid map of field sites at Arapaho Prairie in Arthur County, Nebraska. Scale 1 5/16" = 1/4 mile. Shows permanently marked vegetation quadrats, blowouts and ravine washouts, roads, and 100' contour intervals. Part of the map was destroyed by mice. What remains of the map as of 2013 is shown.

Relationship Of Daylength And Prolactin To Resumption Of Reproductive Activity In Anestrous Ewes, Bruce Schanbacher

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Concentrations of prolactin were measured in serum from three groups of Rambouillet ewes for 8 weeks to determine whether changes in prolactin concentrations were important during the transition from anestrus to seasonal breeding. Group I (control ewes) was maintained under conditions of natural daylength;group II (short-day ewes) was exposed abruptly on the longest day of the year to artificially shortened daylengths (8 hr light and 16 hr darkness); group III (CB 154 ewes) was maintained similar to control ewes except each ewe received twice daily im injections of 2-bromo-α-ergocryptine (CB 154). A fertile ram was kept with each group of …

Androgen Secretion And Characteristics Of Testicular Hcg Binding In Cryptorchid Rats, B. D. Schanbacher

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Response of the cryptorchid testis to gonadotrophic stimulation was assessed by comparison of the androgen production capability in vivo and in vitro with that of the normal scrotal testis. Serum androgen concentrations in cryptorchid rats were similar to those in normal rats, and the incremental increase 60 min after 50 i.u. hCG (i.v.) was about 7-fold for both groups. Basal and hCG-stimulated androgen production in vitro was higher for abdominal testes (557 and 3286 ng/pair) than for scrotal tests (157 and 504 ng/pair). Specific binding of hCG by testicular homogenates was slightly higher (P < 0·05)for cryptorchid testes when expressed per unit weight, but Scatchard analysis indicated that although hCG binding affinities did not differ (Ka = 2×10¹⁰ M^-1), hCG binding …

A Guide To The Threatened And Endangered Vascular Plants Of The Lake Mead National Recreation Area, James S. Holland, Wesley E. Niles, Charles L. Douglas, Dennis R. Schramm

Publications (WR)

This illustrated guide was prepared to provide the botanical community, land managers, and other interested persons with a reference that describes and locates the twelve plant taxa currently being considered by the Fish and Wildlife Service for threatened or endangered status in or around the Lake Mead National Recreation Area. The guide is intended to assist managers of government agencies in determining the presence of these species and in defining management programs for their protection. The guide should be consulted prior to any construction project. If a potential conflict is identified, an onsite evaluation should be conducted early in the …

The Effects Of N-Serve On The Availability Of Urea And Ureaformaldehyde Nitrogen On Lolium Perenne L., Ronald E. Schroll

Masters Theses

Laboratory experiments were conducted to determine the effect of "N-Serve" (DOW) on the availability of urea nitrogen and the subsequent greening effect on perennial ryegrass (Lolium perenne L.) seedlings as compared to the availability of nitrogen and subsequent greening from a controlled release ureaformaldehyde fertilizer. A low organic matter sandy loam soil and a high organic matter clay loam soil were used in this study. Soil treatments of urea and ureaformaldehyde fertilizers were applied and incorporated at concentrations of 0, 25, 38, and 50 ppm-N. N-Serve at concentrations of 0.25, 0.50, and 1.0 ppm active ingredient were applied and …

Poultry Manure Fertilization Of Sudangrass, R.L. Nichols, D.W. Allinson

Storrs Agricultural Experiment Station

No abstract provided.

Bulletin No. 24: Garden Guide To Woody Plants: A Plant Handbook, Sally L. Taylor, William A. Niering

Bulletins

100 pp. 1979. Lists and descriptions of over 500 different trees and shrubs useful for landscaping

End Matter, Vol. 3

Great Basin Naturalist Memoirs

No abstract provided.

The Prairie Naturalist Volume 11, Number 4. December 1979

The Prairie Naturalist

THE STATUS OF HERONS, EGRETS AND IBISES IN NORTH DAKOTA ▪ J. T. Lokomoen

RANGE EXPANSION OF BAIRD'S SPARROW IN SOUTH DAKOTA ▪ H. A. Kantrud and C. A. Faanes

NESTING RECORDS OF THE WOOD THRUSH IN NORTH DAKOTA ▪ S. O. Lambeth and D. O. Lambeth

SOME ECOLOGICAL ASPECTS OF MARBLED GODWITS AND WILLETS IN NORTH DAKOTA ▪ K. F. Higgins, L. M. Kirsch, M. R. Ryan and R. B. Renken

NOTES ON THE INCUBATION BEHAVIOR OF BLACK-BELLIED WHISTLING DUCKS ▪ E G. Bolen and E. N. Smith

NOTES

Red Fox Captures Sharp-tailed Grouse at the Lek ▪ S. …

End Matter, Vol. 3, Index

Great Basin Naturalist Memoirs

No abstract provided.

Full Issue, Vol. 3

Great Basin Naturalist Memoirs

No abstract provided.

Front Matter, Vol. 3

Great Basin Naturalist Memoirs

No abstract provided.

Cadmium, Copper, Lead, Nickel, And Zinc Concentrations In Alfalfa In Connecticut, R.W. Taylor, D.W. Allinson

Storrs Agricultural Experiment Station

No abstract provided.

Rare, Threatened And Endangered Vascular Plants In Oregon: An Interim Report, Jean L. Siddall, Kenton L. Chambers, David H. Wagner

Institute for Natural Resources Publications

This report on rare, threatened and endangered vascular plants in Oregon is a basic document in the process of inventorying the state's natural areas * Prerequisite to the orderly establishment of natural preserves for research and conservation in Oregon are (1) a classification of the ecological types, and (2) a listing of the special organisms, which should be represented in a comprehensive system of designated natural areas. The necessary ecological classification was published in the U.S. Forest Service Pacific Northwest Forest and Range Experiment Station document, "Research Natural Area Needs in the Pacific Northwest," by Dyrness et al. (1975). This …

Results Of The Ninth International Winter Wheat Performance Nursery Grown In 1977, S. L. Kuhr, K. D. Wilhelmi, V. A. Johnson, P. J. Mattern, J. W. Schmidt

Nebraska Agricultural Experiment Station: Historical Research Bulletins

This is the ninth report of results from an International Winter Wheat Performance Nursery (IWWPN) organized in 1968 by the Nebraska Agricultural Experiment Station and the Science and Education Administration (SEA), U.S. Department of Agriculture, under a contract with the Agency for International Development, U.S. Department of State. The Nursery was designed to (1) test the adaptation and stability of winter wheat cultivars in a range of latitudes, daylengths, fertility conditions, water management regimes, and disease complexes; (2) identify superior winter cultivars to serve as recipient genotypes for high protein and high lysine genes, (3) test the degree of expression …

Plant Response To The Barstow To Las Vegas Motorcycle Race Of November, 1974, Candace E. Horsley

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine the disturbance spectrum of the perennial plant vegetation by the Barstow to Las Vegas motorcycle race. Transects were taken at the pit area, starting line, and at various locations along the race course. Measurements were also taken in undisturbed control sites near the test areas, the topographic and bio tic features being judged as equal. Methods employed consisted of aerial photograph analysis just before and after the race. On site ground measurements were taken four years after the 1974 motorocycle event. Measurements of diversity, stability, productivity, and community quality were calculated. The …

Bulletin 3967 - Cyanogenetic Plants Of Western Australia, T E H Aplin

Bulletins - 3000 - 3999

This article deals with those native, naturalized and cultivated plants, which by virtue of contained cyanogenetic glycosides, are known to be poisonous or potentially poisonous to livestock in Western Australia.

Cyanogenetic glycosides are chemical compounds which contain a cyanogen (cyanide) radical combined with a sugar molecule. The sugar moiety may differ in glycosides obtained from different plants, and as a consequence glycosides from different plants, containing different sugar moieties, may be given different names.

When a cyanogenetic glycoside is broken down by enzyme action, through injury to the plant or by microbial action in the digestive system of the animal, …

Distribution Of Plants With Extrafloral Nectaries And Ants At Two Elevations In Jamaica, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Frequencies of plants with extrafloral nectaries were determined for two elevations in Jamaica. Extrafloral nectaries were found on 0.28 of the plants at sea level (Happy Grove, Portland) and 0.00 of the plants at 1310 m (Whitfield Hall, St. Thomas). Ant abundance, as indicated by discovery of and recruitment to baits, was greater at the lower elevation site. However, despite the apparent absence of plants with extrafloral nectaries, there were abundant ants at 1310 m.

Subject And Author Index For Bulletins Of The Storrs Agricultural Experiment Station, Mohini Mundkur

Storrs Agricultural Experiment Station

Storrs Agricultural Experiment Station Bulletin #453, 68 pages.

Ecotypic Differentiation Of Andropogon Virginicus L. In Relation To Strip Mine Spoil Banks, Valina Kay Hurt

Masters Theses & Specialist Projects

Reciprocal plantings of populations of broomsedge, taken from an abandoned strip mine and from an abandoned farm plot in south central Kentucky, on strip mine spoil and abandoned field soil resulted in patterns of populations differentiation. Clonal plantings of populations from strip mine habitats and old field development appeared equal in height and biomass when grown on old field soils in both field trials and growth chamber studies. Populations when planted in strip mine soils in field trials and controlled growth experiments. Later flowering in strip mine populations may be a key to survival strategy in the harsh microclimates of …

Bacteriological Quality Of Runoff Water From Pastureland, John W. Doran, D.M. Linn

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Runoff from a cow-calf pasture in eastern Nebraska was monitored for total coliforms (TC), fecal coliforms (FC), and fecal streptococci (FS) during 1976, 1977, and 1978. Bacteriological counts in runoff from both grazed and ungrazed areas generally exceeded recommended water quality standards. The FC group was the best indicator group of the impact of grazing. Rainfall runoff from the grazed area contained 5 to 10 times more FC than runoff from the fenced, ungrazed area. There was little difference in TC counts between the two areas, but FS counts were higher in runoff from the ungrazed area and reflected the …

Some Effects Of A Grazer, Hyalella Azteca On Ecosystem Level Properties In Aquatic Microcosms, Martin D. Werner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study to determine some ecosystem level effects of an aquatic invertebrate grazer, Hyalella azteca, was performed in aquatic ix microcosms. Impact of the grazer was assessed in three general areas: 1) inorganic nutrient levels of the microcosm water column, 2) productivity and respiration of the biotic community, and 3) plant community composition in the microcosms.

The grazing amphipod caused inorganic phosphorus and nitrogen (except ammonia) levels to be elevated in the microcosms. The increase was due, at least partially, to excretion of nutrients into the water by the amphipod. The presence of H. azteca did not significantly …

Two Basic Methodological Choices In Wildland Vegetation Inventories: Their Consequences And Implications, Donald Alan Shute

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In designing inventories of wildland vegetation, two of the many basic methodological choices are: 1) whether data are collected, reduced, and stored in discrete classes or as continuous variables, and 2) whether data are gathered as general purpose variables to bear upon many questions, or as specific purpose variables optimized for only one type of prediction. The effects of these two choices on accuracy of vegetation inventories to predict plant community production were examined by comparing regression models built upon differing sets of independent variables "inventoried" from a common data base. Contrary to expectations, discrete variables of classified community types …

Bulletin 3992 - Nitrogenous Fertilisers For Cereal Production, M. G. Mason

Bulletins - 3000 - 3999

Because fertiliser prices continue to rise, it is becoming increasingly important to understand what affects the response to fertilisers by crops.

Among the many factors influencing crop response to nitrogen applications, the most important are the season, soil type, paddock history, time of application and source of nitrogen. Before deciding whether to use nitrogen on a cereal crop, which source to use and at what rate, the farmer needs some understanding of how these factors work.

In Vitro Experiments On Totipotency Of Dacus Carota, Karl L. Ruser

Journal of the Minnesota Academy of Science

The intent of this project was to induce the totipotency of carrot cells in tissue culture. The information gathered would be applied to work with woody plants. Differentiated cells removed from the root were cultured in vitro using a modified White's medium. Callus was initiated and successfully sub cultured. Roots and the production of chlorophyll have been initiated in the cultures. Because some specialized equipment and facilities for tissue culture were not available at the beginning of the project, it took considerable time to gather and improvise them. A roller tube culture mixer was constructed, using the mechanism from a …

1979 Field Crops Experiments, P. Mcr. Wood

Experimental Summaries - Plant Research

Field crops experiments resistance of lupins to Phomopsis leptostromiformis. (P.McR. Wood, Plant Research Division, J. Hamblin, Plant Production Division). Stage 1-2 Plant Breeders' Plots. Phomopsis infection of 96 entries (replicated) was assessed just prior to harvest at seven sites - Chapman Valley Research Station (CVRS), Badgingarra Research Station (BRS), Wongan Hills Research Station (WHRS), Avondale Research Station (ARS), Mount Barker Research Station (MBRS), Esperance Downs Research Station (EDRS) and on a farmer's property at Eradu. At four sites, CVRS, Eradu, MBRS and EDRS, only very low levels of infection were apparent. At the other three sites, the currently available varieties …