Genetics Commons^™

Characterization Of A Novel Mitochondrial Plasmid In Brassica, Mackenzie Strehle

UCARE: Research Products

Possessing some of the largest and most complex genomes of any eukaryotic organelles, plant mitochondria are notorious for their rapidly rearranging genetic framework. In addition to containing a large and complex mitochondrial genome, the mitochondria of several plants in the genus Brassica have also been shown to contain an independent, self-replicating linear plasmid. Interestingly, the plasmid appears to be able to move independently between the cytoplasm and the mitochondria, and it can be paternally inherited, unlike the rest of the mitochondrial genome. The plasmid also has features similar to those of adenoviruses, including terminal inverted repeats and covalently bound proteins …

A Concept Analysis Of Resilience Integrating Genetics, Kosuke Niitsu, Julia F. Houfek, Cecilia R. Barron, Scott F. Stoltenberg, Kevin A. Kupzyk, Michael J. Rice

Department of Psychology: Faculty Publications

Although clinicians and researchers are interested in the phenomenon of resilience, there is no agreed-upon definition of resilience. Scientific evidence suggests that resilience is influenced by intrapersonal (e.g., personality traits) and environmental (e.g., social support) variables. A concept analysis was conducted to better understand the meaning of resilience. In this analysis, the antecedent of resilience was a potentially traumatic event; the defining attributes were ego-resiliency, emotion regulation, social support, and heredity; and the consequences were none to mild psychopathological symptoms and positive adaptation. This analysis can help nurses better understand resilience and its relationships …

Ptsd, Alcohol Dependence, And Conduct Problems: Distinct Pathways Via Lability And Disinhibition, Jeffrey S. Simons, Raluca M. Simons, Carol O'Brien, Scott F. Stoltenberg, Jessica A. Keith, Jaime A. Hudson

Department of Psychology: Faculty Publications

This study tested the role of affect lability and disinhibition in mediating associations between PTSD symptoms and two forms of alcohol-related problems, dependence syndrome symptoms (e.g., impaired control over consumption) and conduct problems (e.g., assault, risk behaviors). Genotype at the serotonin transporter linked polymorphic region (5-HTTLPR) was hypothesized to moderate associations between traumatic stress and PTSD symptoms. In addition, the study tested whether childhood traumatic stress moderated associations between combat trauma and PTSD symptoms. Participants were 270 OIF/OEF/OND veterans. The hypothesized model was largely supported. Participants with the low expression alleles of 5-HTTLPR (S or L_G) exhibited stronger …

A Systematic Review And Secondary Data Analysis Of The Interactions Between The Serotonin Transporter 5-Httlpr Polymorphism And Environmental And Psychological Factors In Eating Disorders, Vanja Rozenblat, Deborah Ong, Matthew Fuller-Tyszkiewicz, Kirsti Akkermann, David Collier, Rutger C. M. E. Engels, Fernando Fernandez-Aranda, Jaanus Harro, Judith R. Homberg, Andreas Karwautz, Evelyn Kiive, Kelly K. Klump, Sarah E. Racine, Jodie Richardson, Howard Steiger, Scott F. Stoltenberg, Tatjana Van Strien, Gudrun Wagner, Janet Treasure, Isabel Krug

Department of Psychology: Faculty Publications

Objectives: To summarize and synthesize the growing gene × environment (G × E) research investigating the promoter region of the serotonin transporter gene (5-HTTLPR) in the eating disorders (ED) field, and overcome the common limitation of low sample size, by undertaking a systematic review followed by a secondary data meta-analysis of studies identified by the review. Method: A systematic review of articles using PsycINFO, PubMed, and EMBASE was undertaken to identify studies investigating the interaction between 5-HTTLPR and an environmental or psychological factor, with an ED-related outcome variable. Seven studies were identified by the systematic review, with complete data sets …

Relationship Between Morphogenesis And Secretion In The Filamentous Fungus Aspergillus Nidulans, Lakshmi Preethi Yerra

School of Biological Sciences: Dissertations, Theses, and Student Research

Filamentous fungi have a long history in biotechnology for the production of food ingredients, pharmaceuticals and enzymes. The advancements made in recent years have earned filamentous fungi such as Aspergillus species a dominant place among microbial cell factories. Although the model fungus A. nidulans has been extensively studied, the genetic and regulatory networks that underlie morphogenesis and development have yet to be fully characterized. The Rho GTPases (Cdc42 and RacA) are one of the most important regulators of the morphogenetic processes among diverse eukaryotic organisms. Although the functions of these GTPases are relatively well-characterized, little is known about their …

Sex Chromosome-Wide Transcriptional Suppression And Compensatory Cis-Regulatory Evolution Mediate Gene Expression In The Drosophila Male Germline, Emily L. Landeen, Christina A. Muirhead, Lori Wright, Colin D. Meiklejohn, Daven C. Presgraves

School of Biological Sciences: Faculty Publications

The evolution of heteromorphic sex chromosomes has repeatedly resulted in the evolution of sex chromosome-specific forms of regulation, including sex chromosome dosage compensation in the soma and meiotic sex chromosome inactivation in the germline. In the male germline of Drosophila melanogaster, a novel but poorly understood form of sex chromosome-specific transcriptional regulation occurs that is distinct from canonical sex chromosome dosage compensation or meiotic inactivation. Previous work shows that expression of reporter genes driven by testis-specific promoters is considerably lower—approximately 3-fold or more—for transgenes inserted into X chromosome versus autosome locations. Here we characterize this transcriptional suppression of X-linked …

The Maintenance Of Phenotypic Divergence Through Sexual Selection: An Experimental Study In Barn Swallows Hirundo Rustica, Rebecca Safran, Yoni Vortman, Brittany R. Jenkins, Joanna K. Hubbard, Matt Wilkins, Rachel J. Bradley, Arnon Lotem

School of Biological Sciences: Faculty Publications

Previous studies have shown that sexual signals can rapidly diverge among closely related species. However, we lack experimental studies to demonstrate that differences in trait-associated reproductive performance maintain sexual trait differences between closely related populations, in support for a role of sexual selection in speciation. Populations of Northern Hemisphere distributed barn swallows Hirundo rustica are closely related, yet differ in two plumage-based traits: ventral color and length of the outermost tail feathers (streamers). Here we provide experimental evidence that manipulations of these traits result in different reproductive consequences in two subspecies of barn swallow: (H. r. erythrogaster in North …

Divergent Activity Of The Gonadotropin Releasing Hormone Receptor Gene Promoter Among Genetic Lines Of Pigs Is Partially Conferred By Nuclear Factor (Nf)-Kb, Specificity Protein (Sp)1-Like And Gata-4 Binding Sites, Emily A. Mcdonald, Jacqueline E. Smith, Rebecca A. Cederberg, Brett R. White

Department of Animal Science: Faculty Publications

BACKGROUND: Binding of gonadotropin-releasing hormone (GnRH) to its receptor (GnRHR) on gonadotropes within the anterior pituitary gland is essential to reproduction. In pigs, the GnRHR gene is also located near a genetic marker for ovulation rate, a primary determinant of prolificacy. We hypothesized that pituitary expression of the GnRHR gene is alternatively regulated in genetic strains with elevated ovulation rates (Chinese Meishan and Nebraska Index) vs. standard white crossbred swine (Control).

METHODS: Luciferase reporter vectors containing 5118 bp of GnRHR gene promoter from either the Control, Index or Meishan swine lines were generated. Transient transfection of line-specific, full length, deletion …

Identification Of Qtls For Resistance Against Rhizoctonia Solani And Phoma Glycinicola In Soybeans (Glycine Max L. Merr), Herbert Sserunkuma

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

A QTL (Quantitative trait locus) is a chromosome location of a gene controlling a specific phenotypic trait. The trait maybe governed by multiple genes. Fungal pathogens are responsible for over 50% of all soybean diseases. Rhizoctonia solani Kühn causes seedling dumping off, root and hypocotyl rots and other disease in soybeans. Phoma glycinicola de Gruyter & Boerema causes Red leaf blotch disease, predominantly in Sub-Saharan Africa. There is no reported complete resistance against these fungal pathogens in soybeans. Reaction to R.solani is reportedly a quantitative trait controlled by major and minor genes. Three QTLs contributing to reaction to R. solani …

Non-Essentiality Of Alr And Muri Genes In Mycobacteria, Philion L. Hoff, Denise Zinniel, Raúl G. Barletta

UCARE: Research Products

Amino acids are the building blocks of life. If DNA is the blueprint, amino acids are the lumber that proteins are built with. Proteins are built with left-handed, L- forms of amino acids. Bacteria have an essential cell wall component that happens to be an exception: peptidoglycan. Bacteria have enzymes called racemases that convert L- amino acid forms into right-handed, D- forms. Amino acids participate in many reactions with keto acids. Transaminases allow conversion between amino acids by transfer of an amino group.

Previous reports claimed there is no D-ala transaminase activity in mycobacteria and thus alr and murI genes …

Reducing The Potential For Acrylamide Formation In Wheat Products, Amy Hauver, P. Stephen Baenziger, Mary J. Guttieri

UCARE: Research Products

Acrylamide, a chemical formed from free asparagine and reducing sugars during high-temperature cooking via the Maillard reaction (i.e. frying or baking) of high starch foods is deemed ‘probably carcinogenic to humans’ based on its affect in mice. In April of 2002, a group of Swedish researchers reported findings that presented evidence that heat-treated, starch-rich foods contained high levels of acrylamide, later linking the production of acrylamide to the Maillard reaction. A number of other studies have been done to link dietary intake of acrylamide to human cancers and other health effects, although many have had inconclusive results. Nevertheless, the World …

Examining Maternal Obesity Effects On Oogenesis, Follicular Development, And Embryonic Myogenesis, Chris Lindeman, Jennifer Wood

UCARE: Research Products

The CDC estimates that more than one-third of U.S. adults (approximately 78.6 million) are obese. Despite national efforts to combat this with diet and exercise, the number of obese adults and children continues to climb. It is critical to emphasize that obesity can lead to lifelong, chronic complications and health risks including hypertension, heart disease, and diabetes.

Diet and obesity also have important impacts on the reproductive health of female including the ability to become pregnant (fertility) and risk for complications during pregnancy. Furthermore, for women who do become pregnant, obesity can affect the development of the embryo and fetus, …

Molecular Analysis Confirming The Introduction Of Nile Crocodiles, Crocodylus Niloticus Laurenti 1768 (Crocodylidae), In Southern Florida, With An Assessment Of Potential For Establishment, Spread, And Impacts., Michael R. Rochford, Kenneth L. Krysko, Frank J. Mazzotti, Matthew W. Shirley, Mark W. Parry, Joseph A. Wasilewski, Jeffrey S. Beauchamp, Christpher R. Gillette, Edward F. Metzger Iii, Michiko A. Squires, Louis A. Somma

Papers in Herpetology

The state of Florida, USA, has more introduced herpetofauna than any other governmental region on Earth. Four species of nonnative crocodilians have been introduced to Florida (all since 1960), one of which is established. Between 2000–2014 we field-collected three nonnative crocodilians in Miami-Dade County, Florida, and one in Hendry County, Florida. We used DNA barcoding and molecular phylogenetics to determine species identification and native range origin. Also, we described diet, movement, and growth for one crocodile. Our molecular analyses illustrated that two of the crocodiles we collected are most closely related to Nile Crocodiles (Crocodylus niloticus) from South Africa, suggesting …

Is A Mitochondrial Plasmid Really A Virus?, Mackenzie Strehle

UCARE: Research Products

In addition to containing a large and complex mitochondrial genome, the mitochondria of several species of plants have been shown to contain an independent, self-replicating DNA molecule in the form of a plasmid. Plants in the Brassica genus contain a linear plasmid that is approximately 11.6 kilobases in length. The plasmid is characterized by the presence of terminal inverted repeats and covalently bonded proteins at its termini (Handa 2008). The plasmid also contains six ORFs that encode DNA and RNA polymerases and a number of unknown proteins (Figure 1). Currently, both the function of this plasmid and the mechanisms by …

A Mitochondrial Dna-Based Computational Model Of The Spread Of Human Populations, Peter Revesz

School of Computing: Faculty Publications

This paper presents a mitochondrial DNA-based computational model of the spread of human populations. The computation model is based on a new measure of the relatedness of two populations that may be both heterogeneous in terms of their set of mtDNA haplogroups. The measure gives an exponentially increasing weight for the similarity of two haplogroups with the number of levels shared in the mtDNA classification tree. In an experiment, the computational model is applied to the study of the relatedness of seven human populations ranging from the Neolithic through the Bronze Age to the present. The human populations included in …

Corrigendum: The Arabidopsis Homologs Of Trithorax (Atx1) And Enhancer Of Zeste (Clf) Establish ‘Bivalent Chromatin Marks’ At The Silent Agamous Locus, Abdelaty Saleh, Ayed Al-Abdallat, Ivan Ndamukong, Raul Alvarez-Venegas, Zoya Avramova

School of Biological Sciences: Faculty Publications

The authors wish to draw the attention to two irregularities in Figures 2a and 4. Both concern errors in duplicating images of "empty" lanes illustrating absence of DNA bands. We regret these omissions and apologize to readers for the inconvenience caused. The results and conclusions remain valid.

Genetic And Genomic Basis Of Antibody Response To Porcine Reproductive And Respiratory Syndrome (Prrs) In Gilts And Sows, Nick V. Serão, Robert A. Kemp, Benny Mote, Philip Willson, John C.S. Harding, Stephen C. Bishop, Graham S. Plastow, Jack C.M. Dekkers

Department of Animal Science: Faculty Publications

Background: Our recent research showed that antibody response to porcine reproductive and respiratory syndrome (PRRS), measured as sample-to-positive (S/P) ratio, is highly heritable and has a high genetic correlation with reproductive performance during a PRRS outbreak. Two major quantitative trait loci (QTL) on Sus scrofa chromosome 7 (SSC7; QTL_MHC and QTL₁₃₀) accounted for ~40 % of the genetic variance for S/P. Objectives of this study were to estimate genetic parameters for PRRS S/P in gilts during acclimation, identify regions associated with S/P, and evaluate the accuracy of genomic prediction of S/P across populations with different prevalences of …

Bois 412/812: Human Genetics—A Peer Review Of Teaching Project Benchmark Portfolio, Colin D. Meiklejohn

UNL Faculty Course Portfolios

This portfolio focuses on Human Genetics, an upper-division course taken primarily by biology majors to fulfill elective credit in their degree. This course studies the genetic basis for human variation, with the goal of placing this variation in the context of human evolutionary history and the consequences of this variation for medical understanding and treatments. In Human Genetics, students complete an original synthetic research paper on a human genetic disorder. Through writing this paper, students are expected to learn how to navigate electronic databases and online resources on human genetic diseases, and to read and synthesize the primary scientific literature. …

Rfx Transcription Factors Are Essential For Hearing In Mice, Ran Elkon, Beatrice Milon, Laura Morrison, Manan Shah, Sarath Vijayakumar, Manoj Racherla, Carmen C. Leitch, Lorna Silipino, Shadan Hadi, Michèle Weiss-Gayte, Emmanuèle Barras, Christoph D. Schmid, Aouatef Ait-Lounis, Ashley Barnes, Yang Song, David J. Eisenman, Efrat Eliyahu, Gregory I. Frolenkov, Scott E. Strome, Bénédicte Durand, Norann A. Zaghloul, Sherri M. Jones, Walter Reith, Ronna Hertzano

Department of Special Education and Communication Disorders: Faculty Publications

Sensorineural hearing loss is a common and currently irreversible disorder, because mammalian hair cells (HCs) do not regenerate and current stem cell and gene delivery protocols result only in immature HC-like cells. Importantly, although the transcriptional regulators of embryonic HC development have been described, little is known about the postnatal regulators of maturating HCs. Here we apply a cell type-specific functional genomic analysis to the transcriptomes of auditory and vestibular sensory epithelia from early postnatal mice. We identify RFX transcription factors as essential and evolutionarily conserved regulators of the HC-specific transcriptomes, and detect Rfx1,2,3,5 and 7 in the developing HCs. …

An Incremental Phylogenetic Tree Algorithm Based On Repeated Insertions Of Species, Peter Revesz, Zhiqiang Li

School of Computing: Conference and Workshop Papers

In this paper, we introduce a new phylogenetic tree algorithm that generates phylogenetic trees by repeatedly inserting species one-by-one. The incremental phylogenetic tree algorithm can work on proteins or DNA sequences. Computer experiments show that the new algorithm is better than the commonly used UPGMA and Neighbor Joining algorithms.

Vestibular Dysfunction, Altered Macular Structure And Trait Localization In A/J Inbred Mice, Sarath Vijayakumar, Teresa E. Lever, Jessica Pierce, Xing Zhao, David Bergstrom, Yunxia Wang Lundberg, Timothy A. Jones, Sherri M. Jones

Department of Special Education and Communication Disorders: Faculty Publications

A/J mice develop progressive hearing loss that begins before one month of age and is attributed to cochlear hair cell degeneration. Screening tests indicated this strain also develops early onset vestibular dysfunction and has otoconial deficits. The purpose of this study was to characterize the vestibular dysfunction and macular structural pathology over the lifespan of A/J mice. Vestibular function was measured using linear vestibular evoked potentials (VsEPs). Macular structural pathology was evaluated using light microscopy, SEM, TEM, confocal microscopy and Western blotting. Individually, vestibular functional deficits in mice ranged from mild to profound. On average, A/J mice had significantly reduced …

Deletion Of Shank1 Has Minimal Effects On The Molecular Composition And Function Of Glutamatergic Afferent Postsynapses In The Mouse Inner Ear, Jeremy P. Braude, Sarath Vijayakumar, Katherine Baumgarner, Rebecca Laurine, Timothy A. Jones, Sherri M. Jones, Sonya J. Pyott

Department of Special Education and Communication Disorders: Faculty Publications

Abstract

Shank proteins (1-3) are considered the master organizers of glutamatergic postsynaptic densities in the central nervous system, and the genetic deletion of either Shank1, 2, or 3 results in altered composition, form, and strength of glutamatergic postsynapses. To investigate the contribution of Shank proteins to glutamatergic afferent synapses of the inner ear and especially cochlea, we used immunofluorescence and quantitative real time PCR to determine the expression of Shank1, 2, and 3 in the cochlea. Because we found evidence for expression of Shank1 but not 2 and 3, we investigated the morphology, composition, and function of afferent postsynaptic densities …

The Complexities Of Female Mate Choice And Male Polymorphisms: Elucidating The Role Of Genetics, Age, And Mate-Choice Copying, Kasey D. Fowler-Finn, Laura Sullivan-Beckers, Amy M. Runck, Eileen A. Hebets

Eileen Hebets Publications

Genetic, life history, and environmental factors dictate patterns of variation in sexual traits within and across populations, and thus the action and outcome of sexual selection. This study explores patterns of inheritance, diet, age, and mate-choice copying on the expression of male sexual signals and associated female mate choice in a phenotypically diverse group of Schizocosa wolf spiders. Focal spiders exhibit one of two male phenotypes: ‘ornamented’ males possess large black brushes on their forelegs, and ‘non-ornamented’ males possess no brushes. Using a quantitative genetics breeding design in a mixed population of ornamented/non-ornamented males, we found a strong genetic basis …

The Trehalose Pathway In Maize: Conservation And Gene Regulation In Response To The Diurnal Cycle And Extended Darkness, Clémence Henry, Samuel W. Bledsoe, Allison Siekman, Alec Kollman, Brian M. Waters, Regina Feil, Mark Stitt, L. Mark Lagrimini

Department of Agronomy and Horticulture: Faculty Publications

Energy resources in plants are managed in continuously changing environments, such as changes occurring during the day/night cycle. Shading is an environmental disruption that decreases photosynthesis, compromises energy status, and impacts on crop productivity. The trehalose pathway plays a central but not well-defined role in maintaining energy balance. Here, we characterized the maize trehalose pathway genes and deciphered the impacts of the diurnal cycle and disruption of the day/night cycle on trehalose pathway gene expression and sugar metabolism. The maize genome encodes 14 trehalose-6-phosphate synthase (TPS) genes, 11 trehalose-6-phosphate phosphatase (TPP) genes, and one trehalase gene. Transcript abundance of most …

Redox Regulation Of Protein Translation In Eukaryotes, Maxim Gerashchenko

Department of Biochemistry: Dissertations, Theses, and Student Research

Gene expression may be controlled at multiple levels, e.g., through genomic architecture, transcription and translation. In the current work, we focused on regulation of protein synthesis. Historically, the investigation of the regulation of gene expression at the level of translation lagged behind the transcriptional control because of the lack of accessible high-throughput methods. Our research has begun with the finding of the use of alternative non-AUG start codon in thioredoxin-glutathione reductase (TGR), a selenoprotein involved in redox control during male reproduction. The use of this codon, CUG, relies on the Kozak consensus sequence and ribosomal scanning mechanism. However, the CUG …

Stress Responses And Energy Storage In Drosophila Melanogaster Selected For Resistance To A Gram-Positive Bacillus Cereus Spores, Zhen Hu

School of Biological Sciences: Dissertations, Theses, and Student Research

A survival response study was carried out by using D. melanogaster and the opportunistic pathogen B. cereus as the agent of selection. The spores of B. cereus, a gram-positive bacteria that can cause the human pathogen disease, were applied in our artificial laboratory selection. Selected lines were treated with B. cereus spores. Wound control lines were punctured with a needle dipped into sterile H₂O. Control lines did not apply any treatment. Three different environmental treatments were used within each line type (autoclaved spores of B.cereus, sterile H₂O and no treatment). The autoclaved spores were …

H3k27me3 And H3k4me3 Chromatin Environment At Super-Induced Dehydration Stress Memory Genes Of Arabidopsis Thaliana, Ning Liu, Zoya Avramova, Michael Fromm

School of Biological Sciences: Faculty Publications

Pre-exposure to a stress may alter the plant’s cellular, biochemical, and/or transcriptional responses during future encounters as a “memory” from the previous stress. Genes increasing transcription in response to a first dehydration stress, but producing much higher transcript levels in a subsequent stress, represent the super-induced “transcription memory” genes in Arabidopsis thaliana. The chromatin environment (histone H3 tri-methylations of Lys 4 and Lys 27, H3K4me3, and H3K27me3) studied at five dehydration stress memory genes revealed existence of distinct memory-response subclasses that responded differently to CLF deficiency and displayed different transcriptional activities during the watered recovery periods. Among the most …

Construction Of A Live-Attenuated Hiv-1 Vaccine Through Genetic Code Expansion, Nanxi Wang, Yue Li, Wei Niu, Ming Sun, Ronald Cerny, Qingsheng Li, Jiantao Guo

Qingsheng Li Publications

A safe and effective vaccine against human immunodeficiency virus type 1 (HIV-1) is urgently needed to combat the worldwide AIDS pandemic, but still remains elusive. The fact that uncontrolled replication of an attenuated vaccine can lead to regaining of its virulence creates safety concerns precluding many vaccines from clinical application. We introduce a novel approach to control HIV-1 replication, which entails the manipulation of essential HIV-1 protein biosynthesis through unnatural amino acid (UAA*)-mediated suppression of genome-encoded blank codon. We successfully demonstrate that HIV-1 replication can be precisely turned on and off in vitro.

Includes supporting information.

Qtls Associated With Dry Matter Intake, Metabolic Mid-Test Weight, Growth And Feed Efficiency Have Little Overlap Across 4 Beef Cattle Studies, Mahdi Saatchi, Jonathan E. Beever, Jared E. Decker, Dan B. Faulkner, Harvey C. Freetly, Stephanie L. Hansen, Helen Yampara-Iquise, Kristen A. Johnson, Stephen D. Kachman, Monty S. Kerley, Jaewoo Kim, Daniel D. Loy, Elisa Marques, Holly L. Neibergs, E. John Pollak, Robert D. Schnabel, Christopher M. Seabury, Daniel W. Shike, W. M. Snelling, Matthew L. Spangler, Robert L. Weaber, D. J. Garrick, Jeremy F. Taylor

Department of Animal Science: Faculty Publications

Background: The identification of genetic markers associated with complex traits that are expensive to record such as feed intake or feed efficiency would allow these traits to be included in selection programs. To identify large-effect QTL, we performed a series of genome-wide association studies and functional analyses using 50 K and 770 K SNP genotypes scored in 5,133 animals from 4 independent beef cattle populations (Cycle VII, Angus, Hereford and Simmental × Angus) with phenotypes for average daily gain, dry matter intake, metabolic mid-test body weight and residual feed intake.

Results: A total of 5, 6, 11 and 10 significant …

Use Of Robust Multivariate Linear Mixed Models For Estimation Of Genetic Parameters For Carcass Traits In Beef Cattle, S. O. Peters, K. Kizilkaya, D. J. Garrick, R. L. Fernando, E. J. Pollak, R. Mark Enns, M. De Donato, O. O. Ajayi, I. G. Imumorin

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

Assumptions of normality of residuals for carcass evaluation may make inferences vulnerable to the presence of outliers, but heavy-tail densities are viable alternatives to normal distributions and provide robustness against unusual or outlying observations when used to model the densities of residual effects. We compare estimates of genetic parameters by fitting multivariate Normal (MN) or heavy-tail distributions (multivariate Student’s t and multivariate Slash, MSt and MS) for residuals in data of hot carcass weight (HCW), longissimus muscle area (REA) and 12th to 13th rib fat (FAT) traits in beef cattle using 2475 records from 2007 to 2008 from a large …