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Evaluation Of Beef Cattle Industry Breeding Programs, Keith Hammond

World Congress on Genetics Applied to Livestock Production: 3rd (1986)

A critical evaluation of existing beef cattle breeding programs should include such criteria as: definition of desired genetic changes in performance, breeding value estimation procedures used and accuracy of selection criteria, intensity of selection applied, use of additive differences between breeds and of non-additive variation, maintenance of genetic variability, realised genetic trends and return on investment. Each major production- marketing environment should be treated and correct account take of the industry structure. Such a study would undoubtedly highlight any inadequacies in the essential information. To extend the study to adequately cover all major beef industries would be an enormous task. …

Evaluation Of Crossbreeding Systems For Preweaning Traits In Beef Cattle, M. D. Macneil, L. V. Cundiff, K. E. Gregory, University Of Nebraska-Lincoln

World Congress on Genetics Applied to Livestock Production: 3rd (1986)

Data from a four-generation crossbreeding experiment with Hereford, Angus and Shorthorn cattle were analyzed. Individual, maternal, and grand-maternal additive and heteroic effects on the composite trait of calf weight weaned per cow exposed to breeding and its component traits were evaluated. The parameter estimates were than used to project performance at equilibrium under rotation crossbreeding. The average of two-breed cross rotations is expected to increase calf weight weaned per cow exposed by 18 percent above the average of the three straight breeds. The three-breed cross rotation is expected to increase calf weight weaned per cow exposed by 23 percent above …

Breeding Beef Germ Plasm Composites To Fit Special Environments, Gary Conley

World Congress on Genetics Applied to Livestock Production: 3rd (1986)

A long term breeding program has been designed to take advantage of the heterosis available in a six breed composite while developing a cow which can reproduce on crop residue. A controlled natural selection method has been developed for those reproductive traits which did not lend themselves to objective measurement. Reproductive efficiency and feed conversion will always be desirable traits in beef cattle. Intensive selection pressures were applied to the above traits during the initial generations of crossing to form the composite. Culling rates of 70% were used in the initial and backcross generations. The effectiveness of selection has been …

Feed Intake Specifications In Defining Breeding Objectives, D. R. Notter

World Congress on Genetics Applied to Livestock Production: 3rd (1986)

Development of selection objectives for beef cattle requires consideration of the available feed resources. In production systems with access to liberal quantities of harvested feeds of relatively high quality, selection to improve economic efficiency will normally favor animals with high genetic potentials for the primary production traits. However, these highly productive types may also have relatively high maintenance requirements and be less efficient when nutrient restrictions prevent expression of genetic differences in appetite. This, important genotype × environment interactions may be observed. In range environments, animals may be restricted in the amount of forage that can be harvested. These restrictions …

Genetic Engineering Of Livestock Improvement, Gordon E. Dickerson

World Congress on Genetics Applied to Livestock Production: 3rd (1986)

Genetic engineering requires clearly defined objectives, adequate genetic variability and effective methods of selection. In a given production-marketing System, relative importance of genetic change in alternative traits can be estimated from expected effects on cost per unit of output, using available biological and economic information. Diversity among existing breeds and their crosses is a primary and quickly usable genetic resource, and its management for future needs is a public concern. Better physiological and biochemical understanding of the genetic controls of animal development and function is important to permit more effective selection for efficiency of animal production under diverse environments. Long-term …

Development Of The Relative Economic Weights For Linear And Quadratic Bioeconomic Objectives In Commercial Broilers, M. K. Akbar, D. L. Harris, C. R. Arboleda

Roman L. Hruska U.S. Meat Animal Research Center: Reports

The approach of Harris (1970) and Harris et al. (1984) was used to develop mathematical profit functions for describing the bioeconomic objectives in an integrated three-way cross commercial broiler production system. The reproductive and productive performances of the pureline maternal grandparent female and the single cross female parent were included to reflect the impact of the traits expressed in those populations. The resulting complex function was approximated with linear and quadratic equations. Inputs (costs) in the system included feed, housing, labor and facilities, and processing. Outputs (returns) included salvage value of the cull hens and the processed cut-up broilers. A …

Feedinge Cologyo F Sandhillc Ranesd Urings Pring Migrationin Nebraska, Kenneth Reinecke, Gary L. Krapu

United States Fish and Wildlife Service: Publications

We studied the food habits of midcontinent sandhill cranes (Grus canadensis) during spring 1978 and 1979 at their primary staging area along the Platte River and compared population food and foraging habitat requirements with availability. Crane diets varied among the 3 principal foraging habitats, but not between sexes, ages, or years. Cranes feeding in cornfields ate >99% corn (total dry wt); those feeding in native grasslands and alfalfa fields consumed 79-99% invertebrates. The composite diet of cranes was 97% corn and 3% invertebrates, including 2% earthworms, 0.5% snails, and 0.5% insects. Presumably, corn provided energy, whereas invertebrates from grasslands and …

Ectoparasitism As A Cost Of Coloniality In Cliff Swallows (Hirundo Pyrrhonota), Charles R. Brown, Mary Bomberger Brown

School of Natural Resources: Faculty Publications

Colonially nesting Cliff Swallows (Passeriformes: Hirundo pyrrhonota) in southwestern
Nebraska, USA, are commonly parasitized by hematophagous swallow bugs (Hemiptera: Cimicidae:
Oeciacus vicarius) and fleas (Siphonaptera: Ceratophyllidae: Ceratophyllus celsus). We examined to
what degree these ectoparasites represent a cost of coloniality for Cliff Swallows. The number of
swallow bugs per nest increased significantly with Cliff Swallow colony size. Body mass of nestling
swallows at 10 d of age declined significantly as the number of bugs per nestling increased. By fumigating
half of the nests in some colonies, killing the bugs, and leaving half of the nests as nonfumigated …

G86-797 Causes Of Vaccination-Immunization Failures In Livestock, Duane Rice, E. Denis Erickson, Dale Grotelueschen

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide discusses reasons why vaccinations fail to provide immunity against disease, and how to prevent this from happening.

To comprehend the many reasons for vaccine failure, it is important to understand how animals and humans have the ability to resist infectious diseases. It is also important to know what a disease is and how it affects the animal.

According to Stedman's Dictionary, disease is an interruption, cessation or disorder of body functions, systems or organs. Diseases may be obvious even to the untrained eye, or detectable only by sophisticated testing procedures (subclinical disease). Serious irreversible damage may be …

Effects Of Adding Fat To The Sow Lactation Diet On Lactation And Rebreeding Performance, G. C. Shurson, M. G. Hogberg, N. Defever, S. V. Radecki, E. R. Miller, Win Butler

Department of Animal Science: Faculty Publications

One-hundred-three multiparous sows were randomly assigned to one of two lactation diets containing either no supplemental animal fat (C) or 10% added fat (F) during two seasons, summer (S) and winter (W), in a 2 X 2 factorial arrangement of treatments. Sows were placed on their respective dietary treatments 1 wk prior to farrowing and were fed these diets ad libitum throughout the 28-d lactation period. Weekly feed intake and total feed intake were not affected by diet or season, while weekly metabolizable energy (ME) intake tended to be higher during wk 1 and 3, and was higher (P<.04) during wk 2 for sows fed diet F. Sow weight loss from farrowing to 21 d of lactation and to weaning (28 d) were unaffected by diet or season. Average pig birth weight was .15 kg higher (P<.O1) for pigs born during S compared with those born in W. Sows receiving diet F had heavier litters at 21 d (P<.01) and heavier average pig 21-d weights (P<.O1). This was primarily due to the 13.1% increase (P<.04) in estimated milk yield and the higher fat concentration (P<.O01) of milk consumed by the pigs nursing sows fed diet F. Interval between weaning and re-breeding was shortened by 5.9 d (P<.01) for sows during W than during S, and tended to be lower for sows fed diet F (7.3 d) compared with that of sows fed diet C (9.7 d). Farrowing percentage was unaffected by diet but tended to be increased during W (78.9%) compared with S (65.1%). No differences between mason or diet were noted on number of pigs born or number of pigs born alive in the subsequent parity. No diet • season interactions were observed, except for crude protein concentration of sow's milk, which was higher in milk from sows fed diet C during season W (P<.04).

Ec86-113 A Guide For Planning And Analyzing A Year-Round Forage Program, Steven S. Waller, Lowell E. Moser, Bruce Anderson

University of Nebraska-Lincoln Extension: Historical Materials

Efficient grazing management programs cannot succeed without proper stocing rates. However, proper stocking rate alone will not insure a successful grazing program. Successful grazing management only occurs when all factors affecting production are manipulated properly: season of use; kind, class, and/or combination of animals; grazing distribution; grazing program; fertilization; pest control; and water management as well as stocking rate. The following suggestions in this circular are a guide to initial planning of new pastures and the modification of existing grazing programs.

Kinetic Analysis: Benzo (A) Pyrene In Southeastern Ohio, D. Kolbow, H. Hikichi, C. Tuthill, C. W. Frank, G. B. Wiersma, A. B. Crockett, R. D. Schonbrod

United States Environmental Protection Agency: Publications

Kinetic Analysis has been successful for metallic elements in relatively isolated areas. In this study it is applied to a complex organic compound in a geographical area with a large urban component. Ten media compartments are included, with man as the ultimate receptor. Field data were collected for only 6 of the media and were not used in the analysis but were compared to the calculated steady state concentrations. The greatest differences between calculated and observed values were 4.8-fold for soil and 5.4-fold for sediment. The field sampling regime for soils was biased towards areas of industrialization and probably explains …

Pod Network Membership Directory, September 1986

Professional and Organizational Development Network in Higher Education: Archives

No abstract provided.

An Evaluation Of The Straw Itch Mite, Pyemotes Tritici, For Control Of The Red Imported Fire Ant, D. P. Jouvenaz, C. S. Lofgren

Entomology Papers from Other Sources

The straw itch mite, Pyemotes tritici (LaGreze-Fossat and Montagne) was proposed by Bruce and LeCato (1980) as a potential biological control agent for the red imported fire ant, Solenopsis invicta Buren.

Serologic Survey Of Selected Pathogens In White-Tailed And Mule Deer In Western Nebraska, Jerre L. Johnson, T. Lynwood Barber, Merwin L. Frey, George Nason

West Central Research and Extension Center, North Platte

Exposure of free-ranging white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus) in western Nebraska to selected livestock pathogens was determined by serology and attempted virus isolation. Antibodies to bluetongue virus, epizootic hemorrhagic disease virus, and bovine respiratory syncytial virus were present in both species of deer. No serologic reactors to Brucella or Anaplasma were found. Attempts to isolate bluetongue virus were negative.

Results And Interpretations From A Survey On Agriculturally Related Weather Information, A. Weiss, J. G. Robb

Panhandle Research and Extension Center

A survey of “top” wheat farmers in 12 counties in western Nebraska was undertaken to help guide future research and extension programs (in agricultural meteorology and economics) in the region. One hundred forty-two farmers (59 percent of those receiving questionnaires) responded to the survey. Of the respondents, 42 percent own or are considering purchasing a personal computer; the vast majority of farmers own a rain gage and some form of temperature-measuring device; the respondents were moderately familiar with an existing Automated Weather Data Network in Nebraska; commercial and NOAA weather radio and commercial television are the main sources of weather …

Nebraska Summary: S003 Deutz-Allis 6240, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Economic Evaluation Of Breeding Objectives In Dairy Cattle. Intensive Specialized Milk Production In Temperate Zones, R. E. Pearson

World Congress on Genetics Applied to Livestock Production: 3rd (1986)

In previous world congresses (Cunningham, 1974; Pearson, 1982) methods of estimating weights and choosing traits to include in the selection of objectives were discussed. A more recent discussion of objection functions for breeding decisions is in Allaire and Thraen (1985). This paper will focus more on the specific traits to be included in the selection objective for intensive milk production in temperate zones and on experimental evidence of relative economic importance.

Evaluation Of Inter-Flock Genetic Improvement Programs For Sheep And Goats, G. B. Nicoll, L. Bodin, J. V. Jonmundson

World Congress on Genetics Applied to Livestock Production: 3rd (1986)

Some of the factors involved in inter-flock or breed improvement programs are discussed. Such programs are complicated by the fact that sheep and goats produce a wide range of products under diverse environmental, management and economic circumstances. This leads to problems in defining realistic breeding objectives arising from determining the beneficiaries of genetic improvement, the major genetic decision makers in the industry and the relative importance of the various productive characteristics. The implementation of functional performance recording systems, breeding systems to generate young sire replacements, and testing systems to disseminate genetic improvement, also depend on the conditions under which the …

Evaluation Of Industry Breeding Programs For Sheep And Goats Introduction And Overview, J. N. Clarke

World Congress on Genetics Applied to Livestock Production: 3rd (1986)

In his introduction to the Plenary Session of the First World Congress on Genetics Applied to Livestock Production for Sheep, Rae (1974) pointed to the wide diversity of sheep production systems throughout the world. Goats add further to this range in production environments, husbandry systems and to the variety of products for which these two domestic species are farmed. Such variety makes any consolidated review of Genetic Improvement Programs for sheep and Goats very difficult, especially if all important operational features of ~e production and marketing circumstances for each end product are to be considered in evaluating the success of …

Impact Of Industry Structure, Intensity Of Production And Resource Constraints On Research Breeding Objectives, J. W. Wilton

World Congress on Genetics Applied to Livestock Production: 3rd (1986)

The importance of the structure of the beef industry with respect to crossbreeding programs and division into cow-calf and feedlot segments; intensity of production with respect to market standards, feeds and labour; and resource constraints with respect to feed, labour, land and capital; are discussed and quantified where possible. The use of discounted gene flow provides estimates of relative expression rates which differ with crossbreeding programs and relative sizes of populations of purebred and commercial cattle. The importance of feedback from feedlot to cow-calf to purebred operation is emphasized, for both discounted expression rates and modelling approaches. The composition and …

Optimization Of A Selection Scheme For Milk Composition And Yield In Milking Ewes: Example Of The Lacaune Breed, F. Barillet, J. M. Elsen, M. Roussely

World Congress on Genetics Applied to Livestock Production: 3rd (1986)

Management of the genetic improvement of milking ewes depends: on the obvious fact that they are both dairy animals and sheep. This paper deals with the Lacaune breed situation in France. It paints out the way to build the selection scheme,on two particular aspects:the need to rationalize and simplify milk recording both for milk composition and milk yield, and the concurrent use of AI and natural mating, within the scope of a pyramidal management of the population. We sum up the main results of studies on these different aspects in this paper. In the course of the last twenty years,phenotypic …

Costs And Benefits Of Breed Utilization Strategies In Sheep, William D. Hohenboken

World Congress on Genetics Applied to Livestock Production: 3rd (1986)

Problems involved in choosing appropriate criteria and procedured for economic analyses of breed and mating system evaluation experiments in sheep are described. Literature is reviewed of experiments in which biological or economic efficiency has been investigated. The range in relative economic merit from the poorest to the best group in an experiment typically is from 100 to 120, with values over 140 not uncommon for the best group in an experiment. Heterosis for exonomic traits per ewe mated has ranged from 2% to 26%. Suggestions are presented for consideration in future studies on the economic ramifications of mating system and …

Fatal Human Ascariasis Following Secondary Massive Infection, J. Kevin Baird, M. Mistrey, M. Pimsler, D. H. Connor

United States Public Health Resources

More than '796 Ascaris lumbricoides worms weighing 550 g were recovered at autopsy from a 2-year-old black South African girl. Most of the worms were taken from necrotic small intestine, but worms were also in the stomach, esophagus, intrahepatic and extrahepatic bile ducts, and gallbladder. The worms had caused torsion and gangrene of the ileum, which was interpreted as the cause of death. Worms were formalin-fixed and individually weighed. There were 796 intact worms and 112 appreciably large (>0.2 g) fragments of worms. Statistical analysis of the weights revealed 2 distinct populations of worms: 16 large worms (0.5-2.3 g) …

Two Toxin-Converting Phages From Escherichia Coli 0157:H7 Strain 933 Encode Antigenically Distinct Toxins With Similar Biologic Activities, Nancy A. Strockbine, Lilian R. M. Marques, John W. Newland, H. Williams Smith, Randall K. Holmes, Alison D. O'Brien

United States Public Health Resources

Escherichia coli 0157:H7 strain 933 contains two distinct toxin-converting phages (933J and 933W). The biologic activities and antigenic relationship between the toxins produced by 933J and 933W lysogens of E. coli K-12, as well as the homology of the genes that encode the two toxins, were examined in this study. The 933J and 933W toxins, like Shiga toxin produced by Shigella dysenteriae type 1, were cytotoxic for the same cell lines, caused paralysis and death in mice, and caused fluid accumulation in rabbit ileal segments. The cytotoxic activity of 933J toxin for HeLa cells was neutralized by anti-Shiga toxin, whereas …

The Changing Structure Of Agriculture In Nebraska, Bruce B. Johnson

Center for Public Affairs Research (UNO): Publications

Production agriculture in Nebraska is undergoing profound change. Longrun structural trends have emerged during the financially stressed 1980's. Increasingly, fewer farms account for most of the production volume, while thousands of smaller farms exist by combining nonfarm income with modest farm receipts. By the year 2000, Nebraska may have less than 30,000 farms, half the current number. These trends, in combination with the likelihood of continued economic stress for U.S. agriculture, pose considerable policy challenges to a state whose economy remains heavily interrelated with agriculture. Bold institutional measures need to be made to ease the transition and to position the …

River Conservancy And Agricultural Development Of The North China Plain And Loess Highlands Strategies And Research, Huang Bingwei

Great Plains Quarterly (through 2013)

The North China Plain is the Chinese counterpart to the North American Great Plains. This largest plain in China suffers frequently from drought. Although agricultural production has been significantly increased in recent years, it is still far too low and too unstable to compensate for population growth and the demands of a rising standard of living. One of the major factors limiting agricultural development on the North China Plain is drought. A complication is that not only have surface and underground water resources been utilized almost to their limits for agrarian needs but also water shortages due to rapidly mounting …

The Dust Bowl Historical Image, Psychological Anchor, And Ecological Taboo, William E. Riebsame

Great Plains Quarterly (through 2013)

T he Dust Bowl is an enduring image in the collective consciousness of Americans. Experience and intuition suggest that a few historical events and eras, and their symbols, endure as important cultural memories or benchmarks. The concept of collective cultural myths or symbols is difficult to define or even to examine. Nevertheless, there is compelling prima facie evidence that the American Dust Bowl is a powerful historical symbol; perhaps not one with the power of Frederick Jackson Turner's frontier, but certainly one that focuses attention whenever issues of Great Plains culture and agriculture arise.

In the light of the stringent …

Comparative Responses To Surrogate Motherhood, Thomas A. Eaton

Nebraska Law Review

I. Introduction

II. The Current Status of Surrogate Motherhood ... A. The Basic Transaction ... B. The Legality of Surrogate Motherhood Agreements … 1. Adoption Laws ... a. Prohibiting the Payment of Fees ... b. Restrictions on Private Adoptions and Parental Consent ... 2. Laws Regulating Artificial Insemination and Presumptions of Paternity ... 3. Public Policy

III. Comprehensive Legislation: American, Canadian, British, and Australian Proposals ... A. United States ... B. Canada ... C. United Kingdom ... 1. The Warnock Report ... 2. The Surrogacy Arrangements Act ... D . Australia

IV. The Ethics of Surrogate Parenting ... A. Consequentialist …

Teaching Academic Career Paths: Implications For Faculty Development, Mary Deane Sorcinelli

To Improve the Academy: A Journal of Educational Development

Decision Points

Influences

Individual Factors

Career Image

Significant People

Socio-Historical Events

Career Patterns

Conclusions

References

Notes