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Comparison Of Gelled And Meat Diets For Rearing Screwworm, Cochliomyia Hominivorax (Diptera: Calliphoridae), Larvae, David B. Taylor, Robert L. Mangan Jan 1987

Comparison Of Gelled And Meat Diets For Rearing Screwworm, Cochliomyia Hominivorax (Diptera: Calliphoridae), Larvae, David B. Taylor, Robert L. Mangan

Department of Entomology: Faculty Publications

A liquid diet solidified with an acrylamide-acrylate polymer gelling agent (Water-Lock) was compared with a standard meat diet for rearing screwworm, Cochliomyia hominivorax (Coquerel), larvae. Size and yield of larvae reared on gel diet were equal to, or greater than, those of larvae reared on meat diet. Duration of larval development was increased by ca. 13 h on gel diet; however, variability of pupal weight and larval survival over generations were reduced when gel diet was used. Larval size was also more uniform over the 3-d period when larvae leave the rearing medium to pupate (crawl-off). Gelled diet was more …


Comprehensive Review: Self-Study - Recommendations 1987, Southeast Research & Extension Center Jan 1987

Comprehensive Review: Self-Study - Recommendations 1987, Southeast Research & Extension Center

Southeast Research and Extension Center: Reports and Administration

Foreword
    Introduction ....................................................... 1
    What Makes a Comprehensive Review Most Effective ................... 4
    Members of the Review Team ......................................... 5
    Review Schedule .................................................... 6

Southeast Nebraska Information ......................................... 10

Southeast Research and Extension Center
    History of the Organization ....................................... 11
    Organizational Structure of the University of Nebraska-Lincoln .... 12
    Organizational Structure of the Institute of Agriculture and Natural Resources .. 13
    Internal Relationships of the Institute of Agriculture and Natural Resources ..... 14
    Staff of Southeast Research and Extension Center and the Southeast
           Extension District ....... 15

Southeast Research and Extension Center Programs ....................... 17
    Cooperative Extension Service ..................................... 18 …


Lipogenesis In Adipose Tissue From Ovariectomized And Intact Heifers Immunized Against Estradiol And(Or) Implanted With Trenbolone Acetate, L. C. St. John, P. A. Ekeren, J. D. Crouse, B. D. Schanbacher, S. B. Smith Jan 1987

Lipogenesis In Adipose Tissue From Ovariectomized And Intact Heifers Immunized Against Estradiol And(Or) Implanted With Trenbolone Acetate, L. C. St. John, P. A. Ekeren, J. D. Crouse, B. D. Schanbacher, S. B. Smith

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

Forty-two heifers were allotted randomly to six treatment groups: 1) intact controls, 2) intact heifers implanted with trenbolone acetate, 3) ovariectomized heifers, 4) ovariectomized heifers implanted with trenbolone acetate, 5) intact heifers immunized against estradiol and 6) intact heifers immunized against estradiol and implanted with trenbolone acetate. Blood titers of estradiol-17β were increased over lO0-fold in heifers immunized against estradiol in Freund's complete adjuvant or saline:squalene/arlacel containing Mycobacterium. Lipogenic enzyme activities and acetate incorporation into fatty acids were increased in subcutaneous adipose tissue obtained at slaughter from heifers receiving immunization or the combination of immunization and trenbolone acetate. The increased …


Book Review: Statistics In Omithology, Douglas H. Johnson Jan 1987

Book Review: Statistics In Omithology, Douglas H. Johnson

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

This book, the 29th in Springer-Verlag's Lecture Notes in Statistics series, arose from a one-day meeting held in London in 1982. All but two of the papers presented at that meeting are included, as are additional papers not given in London. Refereeing was done by the two editors.


Blackbird And Starling Feeding Behavior On Ripening Corn Ears, Glen E. Bernhardt, Lynda Van Allsbur, Richard A. Dolbeer Jan 1987

Blackbird And Starling Feeding Behavior On Ripening Corn Ears, Glen E. Bernhardt, Lynda Van Allsbur, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

The behavior of red-winged blackbirds {Agelaius phoemcei/s), common grackles (Quiscalus quiscula), brown-headed cowbirds (Molothrus ater), and juvenile European starlings (Sturnus vulgaris) feeding on ears of corn was studied in an aviary. The species differed significantly in their propensity to attack (penetrate the husk and feed on kernels) ears of corn. Redwings and starlings were more active attackers than grackles and cowbirds. Female redwings were generally more active attackers than males, but less efficient at opening husks and damaging ears. Redwings and starlings used primarily the gaping technique to penetrate husks and expose kernels. Redwings more commonly penetrated the side of …


Research And Development Strategies For A Sustainable Agriculture, Charles A. Francis Jan 1987

Research And Development Strategies For A Sustainable Agriculture, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

"Food production and rural income are two prime concerns of Third World governments. Increased food production and greater food security are goals which countries strive to achieve through agricultural development. The technologies generated by research, commonly known as green revolution methods, have provided an impetus to food production in some favored zones where resources are available to take advantage of this production package. New varieties, productive and responsive to fertilizer, have bought time while countries work to control population growth and develop agriculture and industry" (Francis and Harwood, 1985).

The pioneering work of the International Agricultural Research Centers has been …


Food Quality And Energy Usage In Foodservice Systems: Convective Thermal Processing Of Turkey Rolls, M. E. Matthews, M. E. Zabik, R. B. Maxcy Jan 1987

Food Quality And Energy Usage In Foodservice Systems: Convective Thermal Processing Of Turkey Rolls, M. E. Matthews, M. E. Zabik, R. B. Maxcy

Department of Food Science and Technology: Faculty Publications

This study evaluated sensory and nutritional qualities, microbioloqical and chemical safety of turkey rolls and enerqy use durinq convective thermal processing. Turkey rolls were heat processed in home or institutional convection ovens to an internal temperature of 77 to 80°C in the geometric center of the roll. Treatment combinations included three heat-processing temperatures (105, 135, and 165°C) and two holding treatments (not chilled and chilled for 24 hr) and three hot-holding times (0, 60 and 120 min). Sensory studies of white turkey meat roasted at 165°C and reheated showed that juiciness decreased significantly (p<0.05), compared to roasting at 105 or 135°C without reheating. Juiciness was also decreased significantly (p<0.05) as hot-holding progressed (0 to 120 min).


A Reappraisal Of Tylenchina (Nemata) 1. For A New Approach To The Taxonomy Of Tylenchina, Michel Luc, Armand R. Maggenti, Renaud Fortuner, Dewey J. Raski, Etienne Geraert Jan 1987

A Reappraisal Of Tylenchina (Nemata) 1. For A New Approach To The Taxonomy Of Tylenchina, Michel Luc, Armand R. Maggenti, Renaud Fortuner, Dewey J. Raski, Etienne Geraert

Harold W. Manter Laboratory of Parasitology: Faculty Publications

During the last three decades plant-parasitic nematodes have received increasing attention. This was due mainly to the discovery during the years between 1943-1953 of the first efficient nematicides, DD, EDE and DBCP. This discovery gave a strong impetus to established nematology laboratories and led to the establishment of laboratories in previously "virgin," or nearly so, territories. As a result, there was an increase in the number of nematologists and taxonomic activity. This is particularly true in those areas new to nematology, because the soil fauna is virtually unknown and taxonomy is one of the few activities fitting with limited material …


Virus Disease Of Small Fruits, R. H. Converse Jan 1987

Virus Disease Of Small Fruits, R. H. Converse

School of Biological Sciences: Faculty Publications

This illustrated handbook was compiled by international authorities on virus and viruslike diseases of small fruits. Crops covered are in the plant genera Fragaria (strawberry), Vaccinium (blueberry and cranberry), Ribes (currant and gooseberry), and Rubus (blackberry and raspberry). The history, geographic distribution, importance, symptoms, transmission, cause, detection, and control of virus and viruslike diseases attacking these crops are discussed.


Combining Ability Effects For Mineral Elements In Forage Sorghum Hybrids, H. J. Gorz, Francis A. Haskins, Jeffrey F. Pedersen, W. M. Ross Jan 1987

Combining Ability Effects For Mineral Elements In Forage Sorghum Hybrids, H. J. Gorz, Francis A. Haskins, Jeffrey F. Pedersen, W. M. Ross

Department of Agronomy and Horticulture: Faculty Publications

The concentrations of minerals in forages are important in satisfying animal requirements, but little attention has been given to determining these concentrations in forage sorghum (Sorghum bicolor (L.) Moench.) breeding programs. In this 2-yr study, the objectives were to determine the contents, genetic variability, combining ability effects, and correlations for 12 mineral elements in 49 experimental hybrids of forage sorghum. Mineral elements studied were N, Mg, Si, P, S, CI, K, Ca, Mn, Fe, Cu, and Zn. General combining ability (GCA) effects exceeded specific combining ability (SCA) effects for all elements except P, CI, and Fe in females, and …


Rearing Blister Beetles (Coleoptera, Meloidae), Richard B. Selander Dec 1986

Rearing Blister Beetles (Coleoptera, Meloidae), Richard B. Selander

Insecta Mundi

The receipt, recently, of several requests for information and assistance in rearing blister beetles (Meloidae) has prompted me to prepare the following account of the rearing method used in my laboratory. In order to make the account as useful as possible to new students. I have included a considerable amount of information on meloid bionomics. Larval phases are designated as triungulin (TI, first grub (FG), coarctate (C), and second grub (SG). Where necessary, instar is indicated by a numerical subscript. The pupa and adult are symbolized by P and A, respectively. 1 assume that the reader has some knowledge of …


Division S-4-Soil Fertility And Plant Nutrition: Recovery Of Fertilizer Nitrogen By Wheat As Affected By Fallow Method, J. F. Power, Wallace Wilhelm, John W. Doran Nov 1986

Division S-4-Soil Fertility And Plant Nutrition: Recovery Of Fertilizer Nitrogen By Wheat As Affected By Fallow Method, J. F. Power, Wallace Wilhelm, John W. Doran

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

The fate of fertilizer N applied to crops is of both environmental and economic concern. To follow fertilizer N recovery in western Nebraska, depleted-15N NH4NO3 was surface broadcast in April on winter wheat (Triticum aestivum L.) growing on plots fallowed the previous year by plowing, subtillage, and no-till. Quantities of labeled N taken up by the growing crop, in the upper 100 mm of soil as inorganic N, and in both visible and partially decomposed crop residues, were followed on two sets of plots through the crop-fallow-crop sequence (approximately 117 weeks). About 16 to …


Uptake Of Nitrogen From Soil, Fertilizer, And Crop Residues By No-Till Corn And Soybean, J. F. Power, John W. Doran, Wallace Wilhelm Nov 1986

Uptake Of Nitrogen From Soil, Fertilizer, And Crop Residues By No-Till Corn And Soybean, J. F. Power, John W. Doran, Wallace Wilhelm

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

The relative availability of nitrogen (N) from indigenous soil organic N, immobilized fertilizer N, currently applied fertilizer N, and crop residues is largely unknown. A non-irrigated experiment was conducted on a silty clay loam at Lincoln, NE, with both continuous soybean [Glycine max (L.) Merr.] and corn (Zea mays L.), in which crops were produced with no tillage after surface application of 0, 0.5,1.0, or 1.5 times the quantity of aboveground crop residue produced the previous year. In 1980 and 1981, depleted 15N NH4NO3 (at 45 kg N ha-1) and crop residues …


Mortality Of White-Tailed Deer In Northeastern Minnesota, Michael E. Nelson, L. David Mech Oct 1986

Mortality Of White-Tailed Deer In Northeastern Minnesota, Michael E. Nelson, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Abstract: Two hundred nine white-tailed deer (Odocoileus virginianus) were radiotracked in the central Superior National Forest, Minnesota, from 1973 through winter 1983-84; 85 deaths were recorded. Annual survival was 0.31 for fawns (<1.0 years old), 0.80 for yearling (1.0-2.0 years old) females, 0.41 for yearling males, 0.79 for adult (≥2.0 years old) females, and 0.47 for adult males. Monthly survival rates were high from May through December (0.94-1.00), except for yearling (0.60) and adult (0.69) bucks during the November hunting season. Most mortality occurred from January through April when gray wolf (Canis lupus) predation was an important mortality source for all cohorts. Yearlings males were most vulnerable to hunting and adult males to wolf predation.


Effect Of Pre-Burn Artificial Litter And Prescribed Burning On Smooth Brome (Bromus Inermis Leyss), Patricia R. Boehner Aug 1986

Effect Of Pre-Burn Artificial Litter And Prescribed Burning On Smooth Brome (Bromus Inermis Leyss), Patricia R. Boehner

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Relationship Between Snow Depth And Gray Wolf Predation On White-Tailed Deer, Michael E. Nelson, L. David Mech Jul 1986

Relationship Between Snow Depth And Gray Wolf Predation On White-Tailed Deer, Michael E. Nelson, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Abstract: Survival of 203 yearling and adult white-tailed deer (Odocoileus virginianus) was monitored for 23,441 deer days from January through April 1975-85 in northeastern Minnesota. Gray wolf (Canis lupus)predation was the primary mortality cause, and from year to year during this period, the mean predation rate ranged from 0.00 to 0.29. The sum of weekly snow depths/month explained 51% of the variation in annual wolf predation rate, with the highest predation during the deepest snow.


Agricultural Research Division 100th Annual Report, July 1, 1985, To June 30, 1986 Jun 1986

Agricultural Research Division 100th Annual Report, July 1, 1985, To June 30, 1986

Agricultural Research Division: News and Annual Reports

This 100th Annual Report contains lists of current faculty, active projects, refereed journal publications, brief descriptions of research in selected areas, and the financial report for the period July 1, 1985, through June 30, 1986. Research programs in agriculture, home economics, and natural resources at the University of Nebraska have changed greatly since the U.S. Congress approved the establishment of an Agricultural Experiment Station in each state with the passage of the Hatch Act on March 2, 1887. Although Hatch funds account for a smaller proportion of the total research expenditures in the program today, this legislation continues to be …


Blarina Brevicauda, Sarah B. George, Jerry R. Choate, Hugh H. Genoways Jun 1986

Blarina Brevicauda, Sarah B. George, Jerry R. Choate, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

Blarina Gray, 1838
Blarina Gray, 1838: 124. Type species Corsira (Blarina) talpoides Gray (=Sorex talpoides Gapper = Sorex brevicaudus Say), by original designation. Elevated to generic rank by Lesson, 1842:89.
Brachysorex Duvernoy, 1842:37-41. Type species Brachysorex brevicaudus Duvernoy (=Sorex brevicaudus Say), by original designation.
Talposorex Pomel, 1848:248. Type species Talposorex platyurus Pomel (=Sorex brevicaudus Say), by original designation. Anotus Wagner, 1855:550-55 1. Type species Sorex carolinensis Bachman, by original designation.


Resistance Of Wild Rices, Oryza Spp., To The Brown Planthopper, Nilaparvata Lugensi (Homoptera: Delphacidae), Wu Jung-Tsung, E. A. Heinrichs, F. G. Medrano Jun 1986

Resistance Of Wild Rices, Oryza Spp., To The Brown Planthopper, Nilaparvata Lugensi (Homoptera: Delphacidae), Wu Jung-Tsung, E. A. Heinrichs, F. G. Medrano

Department of Entomology: Faculty Publications

Of 36 wild rices screened, 19 accessions were resistant or moderately resistant to three biotypes of the brown planthopper, Nilaparvata lugens (Stål), and 9 were resistant or moderately resistant to at least one biotype. Resistant accessions were nonpreferred and N. lugens caged on resistant accessions had low food ingestion rates, slow nymphal development, reduced longevity, low fecundity, and consequently low populations. Two wild rice species decreased the percent hatchability of N. lugens eggs. Some moderately resistant accessions have tolerance to N. lugens, as indicated by low plant damage ratings and plant loss and high percentage N. lugens survival and …


Use Of Galactose-Fermenting Streptococcus Thermophilus In The Manufacture Of Swiss, Mozzarella, And Short-Method Cheddar Cheese, Robert W. Hutkins, S.M. Halambeck, H.A. Morris May 1986

Use Of Galactose-Fermenting Streptococcus Thermophilus In The Manufacture Of Swiss, Mozzarella, And Short-Method Cheddar Cheese, Robert W. Hutkins, S.M. Halambeck, H.A. Morris

Department of Food Science and Technology: Faculty Publications

Galactose-fermenting (galactose-posirive) strains of Streptococcus tbermopbilus, alone and combined with galactosepositive and galactose-negative strains of Lactobacillus bulgaricus, were used as starter cultures in the manufacture of Swiss and Mozzarella cheese and were paired with Streptococcus lactis (also galactose-positive) in short-method Cheddar cheese manufacture. Experimental Swiss cheese made with the galactosepositive Streptococcus tbermopbilus starter alone contained a large amount of galactose (ca. 26 to 28 /amol/g of curd) 28 h after hooping compared with control Swiss (< 2/amol/g) made with a nongalactose fermenting strain of Streptococcus tbermopbilus and a galactosepositive strain of Lactobacillus bulgaricus. Mozzarella and short-method Cheddar made with only galactose-positive Streptococcus tbermopbilus also contained …


Population Dynamics And Expansion Rates Of Black-Tailed Prairie Dogs, Lyle A. Crosby, Randy Graham Mar 1986

Population Dynamics And Expansion Rates Of Black-Tailed Prairie Dogs, Lyle A. Crosby, Randy Graham

Vertebrate Pest Conference Proceedings: 12th (1986)

The purpose of this review is to describe population dynamics and annual rates of increase of black-tailed prairie dogs (Cynomys ludovicianus) and to determine annual expansion rates of uncontrolled populations. Their reproductive characteristics, including social behavior are examined as they relate to these factors.

In this analysis, the first step is to determine the average number of male and female prairie dogs of breeding age that are present at each burrow system before and after the reproductive cycle. From this determination the total number of prairie dogs is determined, based on the average density of active burrows for …


Development And Validation Of A Dynamic Model Of Growth And Quality For Cool Season Grasses, W. F. Brown, Lowell E. Moser, Terry J. Klopfenstein Mar 1986

Development And Validation Of A Dynamic Model Of Growth And Quality For Cool Season Grasses, W. F. Brown, Lowell E. Moser, Terry J. Klopfenstein

Department of Agronomy and Horticulture: Faculty Publications

A daily time step model simulating growth and quality of cool season grasses was developed and validated for smooth brome (Bromus inermis Leyss.) under varying environmental and management conditions. Growth predictions are based upon genetic potential, environmental temperature, leaf area, soil moisture, and nitrogen fertilization rate. Daily potential growth rate is a composite of two functions—one relating grass species maximum growth rate to minimum, optimum, and maximum temperatures for plant growth, and another relating daily minimum and maximum air temperatures to time. Multipliers are developed for available leaf area, moisture, and nitrogen, and the minimum of these values modifies …


Inheritance Of Leucoanthocyanidin Content In Sorghum Leaves, Francis A. Haskins, Herman J. Gorz Mar 1986

Inheritance Of Leucoanthocyanidin Content In Sorghum Leaves, Francis A. Haskins, Herman J. Gorz

Department of Agronomy and Horticulture: Faculty Publications

Leucoanthocyanidins (LAC) are structurally related to condensed tannins, a class of compounds having significant effects on the nutritional value of sorghum [Sorghum bicolor (L.) Moench) grain. Little is known of LAC inheritance in sorghum. Mature leaves of 'Colman' and 'White Collier' forage sorghum are high and low, respectively, in LAC content. The objective of the present study was to determine the inheritance of LAC content in reciprocal crosses between these two cultivars, Leaves of field-grown plants were assayed for LAC by a procedure that involved treating methanolic leaf extracts with acid at 50°C to convert the colorless LAC to …


Breed Use And Crossbreeding In Goat Production, Maurice Shelton Jan 1986

Breed Use And Crossbreeding In Goat Production, Maurice Shelton

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

A large portion of the world's 400+ million head of goats cannot be identified as belonging to a specific breed or well defined genetic type. A common definition of a breed might be group of animals which are reasonably distinct and true breeding, can be identified by a name or term and which have an association to maintain and promote the breed. Of the latter requirement is dropped there would still be hundreds of breeds or genotypes of goats on a world basis. Certainly time, space and information available does not permit attempting to treat all of these in this …


Breeding Objectives And Selection Traits For Extensive Beef Cattle Production In The Tropics, D. J. S. Hetzel, G. W. Seifert Jan 1986

Breeding Objectives And Selection Traits For Extensive Beef Cattle Production In The Tropics, D. J. S. Hetzel, G. W. Seifert

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

Breeding objectives are largely determined by market requirements. In the tropics the overall breeding objective can be considered in terms of growth, reproductive rate, carcass quality, adaption and temperament. Growth rate is a simple efficient selection trait. Reasons why potential increases in mature size are not as disadvantageous as in temperate areas are discussed. Reproductive performance has been less important in harsh than benign environments because of the later age of turnoff and higher drought risk of fertile cows. Current market trends towards younger slaughter stock highlight the need to identify marker traits in bulls for cow fertility. Adaptive traits …


Comparison Of Five Dam Breeds Under Two Nutritional Environments, C. E. Thompson, S. G. Woods, S. E. Meadows Jan 1986

Comparison Of Five Dam Breeds Under Two Nutritional Environments, C. E. Thompson, S. G. Woods, S. E. Meadows

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

Crossbreeding has become an accepted practice for beef cattle production. Hybrid vigor or heterosis of crosses among breed of English origin, such as Angus, Hereford and Shorthorn have been well documented. Crosses utilizing breeds of European and dairy breeding have not been well documented for beef production, particularly in the Southeastern part of the United States. As most of the Southeastern U.S. is heavily involved in one-calf programs an evaluation of crossbreds involving the use of British, European and dairy breeding is needed. This study is a portion of a comprehensive research project evaluating the performance of 5 dam breed …


Economic Evaluation Of Breeding Objectives For Milk And Beef Production In Tropical Environments, F. E. Madalena Jan 1986

Economic Evaluation Of Breeding Objectives For Milk And Beef Production In Tropical Environments, F. E. Madalena

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

The influence of some elements of tropical milk production systems on breeding objectives is discussed. Expansion of demand for milk and meat should be expected from increased population and income growth. Relative commercial value of milk fat may be strongly influenced by government policies regulating to proportion of liquid milk consumed. Calf production is an integral part of cow performance under the common practices of hand milking and suckling. Milk letdown may be an important trait for milking in modern dairy parlours. Experimental economic evaluations have referred mainly to comparisons of breeds and crosses, indicating that European × zebu crosses …


Evaluation And Utilization Of Tropical Breeds For Efficient Beef Production In The Tropics: Challenges And Opportunities, Assefaw Tewolde Jan 1986

Evaluation And Utilization Of Tropical Breeds For Efficient Beef Production In The Tropics: Challenges And Opportunities, Assefaw Tewolde

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

Crossbreeding results between tropical breeds and European beef breeds as well as within breed (mainly Zebu) genetic variability for some economically important traits is reviewed. Heterosis of between 9% to 11% has been reported for preweaning growth rate, 2% to 11% for postweaning and carcass traits as well as up to 15% for reproduction related traits in crosses involving Bos indicus and Bos taurus cattle. Maximum heterosis was observed in crosses involving Zebu and Criollo cattle, both well adapted to the tropics. Within breed genetic parameter estimates under tropical conditions are still scanty. Based on the production environment and after …


Feed Intake Specifications In Defining Breeding Objectives, D. R. Notter Jan 1986

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 …


Heterosis On Body Weights In Crosses Among Brahman, Santa Gertrudis And Cheju Native Cattle, D. H. Baik, D. C. Kim Jan 1986

Heterosis On Body Weights In Crosses Among Brahman, Santa Gertrudis And Cheju Native Cattle, D. H. Baik, D. C. Kim

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

Data obtained from 428 calves (59 Cheju native cattle, 60 Brahman, 40 Santa Gertrudis and 269 crossbreds) were analyzed to estimate main effects of environmental factors and heterosis. Mating type, sex of calf, and year of birth were significant sources of variation on most of the weights at preweaning and postweaning periods. Brahman x Cheju native cattle cross showed heterosis of 6.1% on birth weight. Maternal heterosis on weaning weight was 4.9% in Brahman back-crosses and 12.3% in Santa Gertrudis backcrosses.