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1976

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Biomass And Nutrient Content Of Green Material The Size Of Medium And Large Litter, William E. Miller Dec 1976

Biomass And Nutrient Content Of Green Material The Size Of Medium And Large Litter, William E. Miller

Aspen Bibliography

No abstract provided.


Results Of The Sixth International Winter Wheat Performance Nursery Grown In 1974, K. D. Wilhelmi, S. L. Kuhr, V. A. Johnson, P. J. Mattern, J. W. Schmidt Dec 1976

Results Of The Sixth International Winter Wheat Performance Nursery Grown In 1974, K. D. Wilhelmi, S. L. Kuhr, V. A. Johnson, P. J. Mattern, J. W. Schmidt

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

This is the sixth report of results from an International Winter Wheat Performance Nursery (IWWPN) organized in 1968 by the Nebraska Agricultural Experiment Station and the Agricultural Research Service, 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 of winter wheat cultivars in a range of latitudes, daylengths, fertility conditions, water management, and disease complexes; (2) identify superior winter cultivars to serve as recipient genotypes for high protein and high lysine genes, and (3) test the degree of expression and stability of …


Southeast South Dakota Experiment Farm Annual Progress Report, 1976, Agricultural Experiment Station Dec 1976

Southeast South Dakota Experiment Farm Annual Progress Report, 1976, Agricultural Experiment Station

Agricultural Experiment Station and Research Farm Annual Reports

This sixteenth annual report of the research program at the Southeast South Dakota Experiment Farm has special significance for those engaged in agriculture and the agriculturally related businesses in the nine county area of southeast South Dakota. Reports in this document include information on: temperatures and precipitation data, corn breeding and performance, soybean research and planting, crop rotation, grain trials, and animal waste disposal.


Central Crops And Soils Research Station Highmore, South Dakota: Annual Progress Report, 1976, Agricultural Experiment Station Dec 1976

Central Crops And Soils Research Station Highmore, South Dakota: Annual Progress Report, 1976, Agricultural Experiment Station

Agricultural Experiment Station and Research Farm Annual Reports

This is the 1976 progress report for the Central Crops and Soils Research Station at Highmore, South Dakota State College. This document represents the research conducted at the Station during the 1976 crop season including: weather data, weed control for crop production, tillage and fertility experiments, winter wheat, and small grain variety trials.


West River Agricultural Research And Extension Center Progress Report, 1976, Agricultural Experiment Station Dec 1976

West River Agricultural Research And Extension Center Progress Report, 1976, Agricultural Experiment Station

Agricultural Experiment Station and Research Farm Annual Reports

This is the 1976 annual progress report of the West River Crops Soils Research and Extension Center, South Dakota Agricultural Experiment Station. This report includes: a weather summary, small grain variety trials, specialty crop variety trials, sorghum variety testing, irrigated alfalfa trials, water management trials, management, tillage and cultural practices, fertilizer studies on spring wheat, crop disease control, and plot information.


A Bibliography Of Taxonomic Literature Of The Great Plains Flora, With Supplements I, Ii, And Iii, Ralph E. Brooks Dec 1976

A Bibliography Of Taxonomic Literature Of The Great Plains Flora, With Supplements I, Ii, And Iii, Ralph E. Brooks

School of Biological Sciences: Faculty Publications

There is at present no recent comprehensive manual of the Great Plains flora. Consequently, students of the flora must utilize monographs, revisions, and other sources in their work. This bibliography was compiled in order to facilitate location of available literature, and will be useful to anyone interested in the systematics of the plants of the Great Plains. This compilation was produced for the Great Plains Flora Association as an initial step in the preparation of a major flora for the region.

References to the plants of the Great Plains region as recognized in the Atlas of the Great Plains Flora …


Effects Of Time Of Application Of Glyphosate In The Control Of Johnsongrass, Marlin Moody Dec 1976

Effects Of Time Of Application Of Glyphosate In The Control Of Johnsongrass, Marlin Moody

Masters Theses & Specialist Projects

Investigations were conducted to determine the effects of the herbicide glyphosate and its time of application on the control of johnsongrass.

Johnsongrass plots were divided into areas designated undisturbed, spring plowed, and clipped. These areas were compared to determine differences in control of johnsongrass when using glyphosate with different management procedures. Glyphosate was applied at weekly intervals and treatment effects were statistically analyzed. There were three replications of each treatment.

It appears from the results that:

  1. Glyphosate kills approximately 100% of the johnsongrass topgrowth regardless of the application date.

  2. Height of the johnsongrass plant at the time of glyphosate application …


The Prairie Naturalist Vol. 8, Nos. 3 And 4 September-December 1976 Dec 1976

The Prairie Naturalist Vol. 8, Nos. 3 And 4 September-December 1976

The Prairie Naturalist

SPRING MORTALITY OF INSECTIVOROUS BIRDS IN SOUTHERN MANITOBA ▪ J. R. Serie and R. E. Jones

CHRISTMAS BIRD COUNTS FOR NORTH DAKOTA—1976 ▪ R. N. Randall

MOSSES OF THE GREAT PLAINS: INTRODUCTION AND CATALOGUE ▪ S. P. Churchill

NOTES

Fulvous Tree Duck in North Dakota ▪ L. A. Jones

Unusual Mortality of a Saw-whet Owl ▪ H. A. Kantrud

Cardinal and Mockingbird in Jamestown, North Dakota ▪ D. H. and J. E. Johnson

BOOK REVIEWS

Essence of Wilderness ▪ K. T. Killingbeck

The Changing America ▪ L. M. Kirsch

A Government Bird Book ▪ J. F. Cassel

Wildflowers ofthe Rockies …


Evaluation Of Glyphosate In No-Till Double Crop Soybeans Using Varying Volumes & Pressures, Charles Rogers Dec 1976

Evaluation Of Glyphosate In No-Till Double Crop Soybeans Using Varying Volumes & Pressures, Charles Rogers

Masters Theses & Specialist Projects

No-tillage production of crops has developed and become widespread since the late 1950/s. No-till is dependent upon the use of broad spectrum herbicides to kill weeds already growing at planting time. Until recently, this has almost exclusively been paraquat (1,1'-dimethy1-4,4'-bipyridinium ion). Glyphosate [N-(phosphonomethyl)glycine] is a new herbicide which has great potential for use in no -tillage production.

Soybeans (Glycine max L.) were planted in the stubble after wheat (Triticum aestivum L.) was harvested. All plots received applications of the residual herbicides alachlor [2-chioro-2',6'-diethyl-N-(methoxymethyl)acetanilide] and linuron [3-(3,4-dichlorophenv1)-1-methoxy-1-methylurea]. Each plot also received either paraquat or glyphosate or was designated as …


Growth Analysis Of Tall Fescue Genotypes Differing In Yield And Leaf Photosynthesis, Wallace Wilhelm, C. J. Nelson Nov 1976

Growth Analysis Of Tall Fescue Genotypes Differing In Yield And Leaf Photosynthesis, Wallace Wilhelm, C. J. Nelson

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

Leaf growth, dry matter distribution , and carbohydrate content of four tall fescue (Festuca arundinacea Schreb.) genotypes selected for high and low net C02 exchange (NCE) and forage yield were studied in controlled environments t o evaluate the leaf NCE-yield relationship. High yield genotypes produced greater amounts of all plant parts and carbohydrate than the low yield genotypes. Within each yield level the high NCE genotypes produced more dry matter and carbohxdrate. Leaf growth of all genotypes was linear throughout light and dark periods, but rates were 50% greater for high yield genotypes, RGR was similar for all genotypes. NAR …


Nitrate Reductase Activity In Tall Fescue, D. D. Randall, Wallace Wilhelm, R. F. Feuers, C. J. Nelson Nov 1976

Nitrate Reductase Activity In Tall Fescue, D. D. Randall, Wallace Wilhelm, R. F. Feuers, C. J. Nelson

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

An in vitro assay for tall fescue leaf nitrate reductase activity (NRA) was established that required either O.5 % casein or polyvinylpyrrolidone in the extraction medium for maximal activity. Leaf NRA was proportional to light intensity and fertility levels. Mature tissue and high temperature decreased NRA. NRA showed significant genetic variability in broadly based genotypes and genotypes selected for photosynthetic rates and forage yields. However, progeny of the latter did not show significant genetic variability. High coefficients of variation (30-50%) among the heterogeneous progeny may have masked true genetic differences. No significant correlations were found between NRA and photosynthesis or …


Report On Wastewater Disposal To Board Of County Commissioners, Clark County Nevada, Clair N. Sawyer Oct 1976

Report On Wastewater Disposal To Board Of County Commissioners, Clark County Nevada, Clair N. Sawyer

Publications (WR)

This report is concerned with the management of waste-waters and subsurface drainage from the City of Las Vegas and its environs and the BMI complex, all in Clark County, Nevada. The prime objective is to recommend a plan of action which will utilize the natural resources of the area in the least costly manner and still protect Lake Mead for recreational purposes and use as a public water supply, At this writing, conditions in the upper Las Vegas arm of Boulder Basin are quite unsatisfactory for some recreational purposes due to the extensive blooms of algae which develop. Experience at …


Interactions Between Insects And Chemical Components Of Sweetclover, G. R. Manglitz, Herman J. Gorz, Francis A. Haskins, W. R. Akeson, G. L. Beland Oct 1976

Interactions Between Insects And Chemical Components Of Sweetclover, G. R. Manglitz, Herman J. Gorz, Francis A. Haskins, W. R. Akeson, G. L. Beland

Department of Agronomy and Horticulture: Faculty Publications

This review concerns the relationship between chemical components found in sweetclover [Melilotus officinalis (L.) Pall. and M. alba Desr.] tissues and insects feeding on these tissues. Coumarin and its related compounds did not appear to influence the feeding of sweetclover aphids [Therioaphis riehmi [Börner)], pea aphids [Acyrthosiphum pisum (Harris)] or potato leafhoppers [Empoasca fabae (Harris)] , however, these materials appeared attractive to sweetclover weevils (Sitona cylindricollis Fåhraeus) and to adult sweetclover root borers [Walshia miscecolorella (Chambers)]. Conversely the feeding of four species of blister beetles (Epicauta sp.] was inhibited by cis-o-hydroxycinnamic acid …


Mosses Of The Great Plains: Introduction And Catalogue, Steven P. Churchill Sep 1976

Mosses Of The Great Plains: Introduction And Catalogue, Steven P. Churchill

School of Biological Sciences: Faculty Publications

This account initiates a series of articles concerning the mosses of the Great Plains. The boundary of this region (Fig. 1) is adopted in part from a parallel study currently in progress on vascular plants (McGregor et aI., 1977). However, in addition, this moss study includes that region of Canada studied by Bird (1962). The total area included in this study of the Great Plains thus occupies about 665 thousand square miles, extending from southern Manitoba to southeastern Alberta, south to northeastern New Mexico and northwestern Oklahoma.

Crum, Steere and Anderson (1973) have listed 1,170 species, 267 genera, and 58 …


Performance Of Certified Seed Lots Of Dawson Alfalfa, W. R. Kehr, G. R. Manglitz Aug 1976

Performance Of Certified Seed Lots Of Dawson Alfalfa, W. R. Kehr, G. R. Manglitz

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

Breeder, foundation, and certified seed lots of Dawson alfalfa, Medicago sativa L., were tested to determine stability in performance during three generations of seed increase under certification. Two field experiments were conducted, a seeded forage yield test and a space-planted test. Greenhouse experiments included separate tests for resistance to pea aphids, spotted alfalfa aphids, and bacterial wilt. Results obtained on certified Dawson alfalfa seed classes in field and greenhouse experiments were in agreement with the original variety description.


Bacteria In The Air Of Housed Swine Units, L.F. Elliot, T.M. Mccalla, J.A. Deshazer Aug 1976

Bacteria In The Air Of Housed Swine Units, L.F. Elliot, T.M. Mccalla, J.A. Deshazer

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

Two housed, swine-growing-finishing units were studied for numbers of total bacteria, fecal coliforms, Staphylococcus, and Salmonella in the air. At 30.5 and 122 cm from the floor, total colony-forming particles, as tested, averaged 3.4 x 10) and 1.3 x 105/m3 of air, respectively; whereas fecal coliform counts averaged 24 x 103 and 1.9 x 103/m3 of air, respectively. Only 41% of the organisms growing on Staphylococcus 110 medium tested as Staphylococcus. Of 458 Staphylococcus isolates, 5 were coagulase-positive. No Salmonella were detected in the air of the units tested.


Separation Of Kentucky Bluegrass Cultivars Using Peroxidase Isoenzyme Banding Patterns, David J. Wehner, J. M. Duich, T. L. Watschke Jul 1976

Separation Of Kentucky Bluegrass Cultivars Using Peroxidase Isoenzyme Banding Patterns, David J. Wehner, J. M. Duich, T. L. Watschke

Office of the Dean (CAFES) Scholarship

The peroxidase isoenzyme banding pattern of 15 Kentucky bluegrass (Poa pratensis L.) cultivars was investigated for use in identification. Isoenzymes were separated by polyacrylamide slab gel electrophoresis, stained with benzidine-H2O2, and the relative intensities of the bands evaluated with a densitometer. Cultivar separations were made on single seedling samples at the 1% level of confidence using band number, mobility, and intensity ratios. Overall variability of the procedure was evaluated using a horseradish peroxidase standard and the effects of seedling age and seedlot determined. Of the 15 cultivars, 11 could be separated individually, whereas the remaining 4 …


Separation Of Kentucky Bluegrass Cultivars Using Peroxidase Isoenzyme Banding Patterns, David J. Wehner, J. M. Duich, T. L. Watschke Jul 1976

Separation Of Kentucky Bluegrass Cultivars Using Peroxidase Isoenzyme Banding Patterns, David J. Wehner, J. M. Duich, T. L. Watschke

Office of the Dean (CAFES) Scholarship

The peroxidase isoenzyme banding pattern of 15 Kentucky bluegrass (Poa pratensis L.) cultivars was investigated for use in identification. Isoenzymes were separated by polyacrylamide slab gel electrophoresis, stained with benzidine-H2O2, and the relative intensities of the bands evaluated with a densitometer. Cultivar separations were made on single seedling samples at the 1% level of confidence using band number, mobility, and intensity ratios. Overall variability of the procedure was evaluated using a horseradish peroxidase standard and the effects of seedling age and seedlot determined. Of the 15 cultivars, 11 could be separated individually, whereas the remaining …


Comparisons Of Nitrogen Fertilizer Sources Under Kentucky Soil And Climatic Conditions, Kenneth L. Wells, Lloyd W. Murdock, Harold F. Miller Jun 1976

Comparisons Of Nitrogen Fertilizer Sources Under Kentucky Soil And Climatic Conditions, Kenneth L. Wells, Lloyd W. Murdock, Harold F. Miller

Agronomy Notes

A summary of yield data comparing different nitrogen fertilizer sources in field experiments conducted by the Agronomy Department staff should provide information that will help answer some of the inquiries regarding the comparative value of some of the nitrogen fertilizers being marketed in Kentucky. Since the nitrogen rates per acre shown in all tables are ACTUAL NITROGEN the COST PER POUND OF NITROGEN in the different materials is an important consideration when evaluating the various products.


The Prairie Naturalist Volume 8, Nos. 1 And 2. March-June 1976 Jun 1976

The Prairie Naturalist Volume 8, Nos. 1 And 2. March-June 1976

The Prairie Naturalist

THE POTAMOGETONACEAE IN NORTH DAKOTA ▪ G. E. Larson

NOTES

January Record for Western Grebe at Amenia, North Dakota ▪ J. M. Wiehe and J. F. Cassel

An Observation of Possible Mallard Adoption ▪ R. A. Stromstad

Unusual Mortality in California Gulls ▪ G. R. Lingle

Great Horned Owl Predation of Penned Gray Partridge ▪ J. W. Schulz

BOOK REVIEWS

North Dakota's Own Bird Book ▪ B. and A. Gammell

North Dakota's Wildlife ▪ Staff

A New Bird Book for Minnesota ▪ D. H. Johnson

Two New Waterfowl Books ▪ T. J. Dwyer

Two Canadian Bird References ▪ Staff

Canadian …


Comparative Properties Of Bacteriophage Φ6 And Φ6 Nucleocapsid, James L. Van Etten, Les Lane, Carlos Gonzalez, James Partridge, Anne Vidaver May 1976

Comparative Properties Of Bacteriophage Φ6 And Φ6 Nucleocapsid, James L. Van Etten, Les Lane, Carlos Gonzalez, James Partridge, Anne Vidaver

Department of Plant Pathology: Faculty Publications

Nonionic detergent treatments released a nucleocapsid from the enveloped bacteriophage φ6. The nucleocapsid sedimented at nearly the same rate as the whole phage in sucrose density gradients, but the buoyant density in Cs2SO4 changed from 1.22 g/cm3 for the whole phage to 1.33 g/cm3 for the nucleocapsid. The detergent completely removed the lipid and 5 of the 10 proteins from the phage. Surface labeling of the phage and nucleocapsid with 125I revealed that protein P3 was on the outer surface of the whole phage and P8 was on the surface of the nucleocapsid. Both …


Forest Composition Of Rock Creek Gorge A Virgin Forest In Laurel County, Kentucky, Margaret Ringland May 1976

Forest Composition Of Rock Creek Gorge A Virgin Forest In Laurel County, Kentucky, Margaret Ringland

Masters Theses & Specialist Projects

Rock Creek Gorge in Rock Creek Natural Landmark in Laurel County, Kentucky is a deep narrow gorge dominated by Tsuga canadensis (L.) Carr., Oxydendrum arboreum (L.) DC., Betula lenta L. and Liriodendron tulipifera L. Rhododendron maximum L., dominating the understory, is also an important constituent of the gorge. An analysis of the forest composition showed the community to be stable and climax. The dominant species were found in sapling and seedling size classes. The vegetation varied slightly between the east facing and west facing slopes. Hemlock did not attain as high an importance value on the west facing slope, although …


Results Of The Fifth International Winter Wheat Performance Nursery Grown In 1973, J. E. Stroike, K. D. Wilhelmi, V. A. Johnson, J. W. Schmidt, P. J. Mattern Apr 1976

Results Of The Fifth International Winter Wheat Performance Nursery Grown In 1973, J. E. Stroike, K. D. Wilhelmi, V. A. Johnson, J. W. Schmidt, P. J. Mattern

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

This is the fifth report of results from an International Winter Wheat Performance Nursery (IWWPN) organized in 1968 by the Nebraska Agricultural Experiment Station and the Agricultural Research Service, 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 of winter wheat cultivars in a range of latitudes, daylengths, fertility conditions, water management, and disease complexes; (2) identify superior winter cultivars to serve as recipient genotypes for high protein and high lysine genes, and (3) test the degree of expression and stability …


Relationship Between Physiological And Morphological Characteristics And Yield Of Nondormant Alfalfa Clones, A. L. Foutz, Wallace Wilhelm, A. K. Dobrenz Apr 1976

Relationship Between Physiological And Morphological Characteristics And Yield Of Nondormant Alfalfa Clones, A. L. Foutz, Wallace Wilhelm, A. K. Dobrenz

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

Alfalfa (Medicago sativa L.) breeders are constantly striving to improve the productivity of alfalfa. Yields have been increased primarily through the selection of plant materials resistant to insects and diseases. The objective of this study was to evaluate physiological characteristics which might be used as selection criteria in alfalfa improvement. Alfalfa clones were grown under field conditions on a Mojave clay loam soil. Carbon dioxide flux was evaluated in a closed system using an infrared gas analyzer. The physiological variables measured in these studies did not account for the varialion in yield among the clones. Apparent photosynthetic rates, dark …


Blueberry Research Progress Report, Howard Y. Forsythe Jr, Amr A. Ismail, Said A. Goueli, Paul R. Hepler, Arlen D. Draper, John M. Smagula, Stewart Goltz, Alan Langille, Thomas E. Christensen, Homer B. Metzger, Ruth H. True Apr 1976

Blueberry Research Progress Report, Howard Y. Forsythe Jr, Amr A. Ismail, Said A. Goueli, Paul R. Hepler, Arlen D. Draper, John M. Smagula, Stewart Goltz, Alan Langille, Thomas E. Christensen, Homer B. Metzger, Ruth H. True

Wild Blueberry Research Reports

The 1975 edition of the Blueberry Research Progress Report was prepared for the Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include:

1. Insects Affecting the Blueberry

2. Weed Control in Blueberry Fields

3. Pruning of Blueberries

4. Integrated Management of Blueberry Fields

5. Selective Thinning of Black Barrenberries in Lowbush Blueberry Fields with Ethrel

6. The Physiology and Biochemistry of the Development of the Lowbush Blueberry Fruit

7. The Development of Blueberry Varieties Adapted to Maine

8. Factors Regulating Rhizome Initiation and Development in the Lowbush Blueberry

9. Mechanical Blueberry Harvesting

10. …


James Valley Agricultural Research And Extension Center Annual Progress Report, 1976, Agricultural Experiment Station, Plant Science Department Mar 1976

James Valley Agricultural Research And Extension Center Annual Progress Report, 1976, Agricultural Experiment Station, Plant Science Department

Agricultural Experiment Station and Research Farm Annual Reports

This is the 1976 progress report for the James Valley Agricultural Research and Extension Center. The reports in this document represent the research conducted at the Center during 1975. The report includes weather data, information on crop production, irrigation, soil reclamation, performance and variety test, and other experiments conducted at the Redfield, South Dakota Extension Center.


The Effects Of Swathing Wheat On The Date Of Harvest, Yield And Seed Quality, Dennis M. Tekrony, Alan Phillips, Ted Howard Feb 1976

The Effects Of Swathing Wheat On The Date Of Harvest, Yield And Seed Quality, Dennis M. Tekrony, Alan Phillips, Ted Howard

Agronomy Notes

In 1975 approximately 350,000 acres were double-cropped using small grain and soybeans in Kentucky. Due to the low acreage of winter barley (48,000 acres) most of the soybeans were either planted by no-till or conventional means following winter wheat. The major problem with winter wheat in a double-cropping system is that the date of planting for soybeans is delayed. Research at the West Kentucky Experiment Station at Princeton indicates that this delay can reduce soybean yields from 7 to 11 bushels per acre depending upon the soybean variety used. The research at Princeton also indicates no reduction in soybean yields …


Prospects For Control Of Phytopathogenic Bacteria By Bacteriophages And Bacteriocins, Anne K. Vidaver Jan 1976

Prospects For Control Of Phytopathogenic Bacteria By Bacteriophages And Bacteriocins, Anne K. Vidaver

Department of Plant Pathology: Faculty Publications

The last review on bacteriophages and bacteriocins of phytopathogenic bacteria was that of Okabe & Goto (98). All but one (21) of the subsequent reviews (II, 12, 60, 94, 104) have dealt primarily with viruses and bacteriocins of bacteria other than phytopathogens. The most recent microbiological compendia that in­ clude bacteriophages and bacteriocins are of limited value for phytobacteriolo­ gists because the authors generally overlook or ignore such agents (29, 47, 77, 119). However, Adam's classic .book (4), the review by Bradley (II), and the bibliography of Raettig (102) are still of value to phytobacteriologists as are reviews dealing principally …


Report On Rare And Unusual Plant Species Within The Dickey-Lincoln School Lakes Project Area, Charles D. Richards, United States Army Corps Of Engineers, New England Division Jan 1976

Report On Rare And Unusual Plant Species Within The Dickey-Lincoln School Lakes Project Area, Charles D. Richards, United States Army Corps Of Engineers, New England Division

Dickey-Lincoln School Lakes Project

Report on rare and unusual plant species within the Dickey-Lincoln School Lakes project area. New England.


Luteinizing Hormone, Testosterone, Growth And Carcass Responses To Sexual Alteration In The Ram, B. D. Schanbacher, J. J. Ford Jan 1976

Luteinizing Hormone, Testosterone, Growth And Carcass Responses To Sexual Alteration In The Ram, B. D. Schanbacher, J. J. Ford

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

A total of 130 ram lambs were used in a study to determine the effects of sex alteration on serum hormone levels, growth rate and carcass traits. Sex alteration included no treatment (intact rams), scrotal ablation to alter normal testicular secretion (short scrotum rams) and castration to completely remove influences derived from the testes (wethers). Although these data suggest that scrotal ablation at birth did not produce complete azoospermia in Finn-crossbred rams, reduction (P<.01) in testicular weight did produce significant results. Serum testosterone in short scrotum and intact rams was similar, whereas castration resulted in considerably lower concentrations of this steroid (P<.01). On the other hand, serum luteinizing hormone was increased (P<.01) threefold in short scrotum rams and 12-fold in wethers as compared to that of intact rams. Because these results cannot be fully explained by changes in serum testosterone, it is speculated that changes in secretory products of the testis which accompany degeneration of the germinal epithelium are responsible for elevated luteinizing hormone. Post-weaning average daily gain (P<.01) and feed efficiency were highest in intact and short scrotum rams indicating that testosterone (or testis) may be beneficial. Although dressing percentage and adjusted backfat were highest (P<.01) in wethers, carcass weight and yield grade were advantageous (P<.01) in short scrotum and intact rams. Quality grades were similar; all animals reached average choice.