Life Sciences Commons^™

Estimation Of Genetically Effective Breeding Numbers Using A Rejection Algorithm Approach, Uma Ramakrishnan, Jay F. Storz, Barbara L. Taylor, Russell Lande

Jay F. Storz Publications

Polygynous mating results in nonrandom sampling of the adult male gamete pool in each generation, thereby increasing the rate of genetic drift. In principle, genetic paternity analysis can be used to infer the effective number of breeding males (N_ebm). However, this requires genetic data from an exhaustive sample of candidate males. Here we describe a new approach to estimate N_ebm using a rejection algorithm in association with three statistics: Euclidean distance between the frequency distributions of maternally and paternally inherited alleles, average number of paternally inherited alleles and average gene diversity of paternally inherited alleles. We quantify …

Natural Selection Drives Altitudinal Divergence At The Albumin Locus In Deer Mice, Peromyscus Maniculatus, Jay F. Storz, Jean M. Dubach

Jay F. Storz Publications

In populations that are distributed across steep environmental gradients, the potential for local adaptation is largely determined by the spatial scale of fitness variation relative to dispersal distance. Since altitudinal gradients are generally characterized by dramatic ecological transitions over relatively short linear distances, adaptive divergence across such gradients will typically require especially strong selection to counterbalance the homogenizing effect of gene flow. Here we report the results of a study that was designed to test for evidence of adaptive divergence across an altitudinal gradient in a natural population of deer mice, Peromyscus maniculatus. We conducted a multilocus survey of …

Genome Scans Of Dna Variability In Humans Reveal Evidence For Selective Sweeps Outside Of Africa, Jay F. Storz, Bret A. Payseur, Michael W. Nachman

Jay F. Storz Publications

The last 50,000–150,000 years of human history have been characterized by rapid demographic expansions and the colonization of novel environments outside of sub-Saharan Africa. Mass migrations outside the ancestral species range likely entailed many new selection pressures, suggesting that genetic adaptation to local environmental conditions may have been more prevalent in colonizing populations outside of sub-Saharan Africa. Here we report a test of this hypothesis using genome-wide patterns of DNA polymorphism. We conducted a multilocus scan of microsatellite variability to identify regions of the human genome that may have been subject to continent-specific hitchhiking events. Using published polymorphism data for …

Phylogenetic Analyses Of Texas Isolates Indicate An Evolving Subtype Of The Clade B Feline Immunodeficiency Viruses, Eric A. Weaver, Ellen W. Collisson, Margaret Slater, Guan Zhu

Nebraska Center for Virology: Faculty Publications

Rigorous phylogenetic analyses were used to compare the nucleotide sequences of feline immunodeficiency virus strains isolated from Texas and throughout the world. The envelope V3-V4 sequences and capsid gene of the Texas isolates formed a cluster between subtypes B and E. Statistical comparisons with other published sequences confirmed that the Texas group is a unique cluster, possibly a new subtype, arising from subtype B.

Feline immunodeficiency virus (FIV) was initially isolated in 1987 from a cat in California with severe immunodeficiency and has been recognized as a common worldwide feline pathogen (11, 14, 19, 20, 33). FIV-infected cats exhibit a …

Glycosyltransferases Encoded By Viruses, Nicolas Markine-Goriaynoff, Laurent Gillet, James L. Van Etten, Haralambos Korres, Naresh Verma, Alain Vanderplasschen

James Van Etten Publications

Studies of cellular biology in recent decades have highlighted the crucial roles of glycans in numerous important biological processes, raising the concept of glycomics that is now considered as important as genomics, transcriptomics and proteomics. For millions of years, viruses have been co-evolving with their hosts. Consequently, during this co-evolution process, viruses have acquired mechanisms to mimic, hijack or sabotage host processes that favour their replication, including mechanisms to modify the glycome. The importance of the glycome in the regulation of host–virus interactions has recently led to a new concept called ‘glycovirology’. One fascinating aspect of glycovirology is the study …

Effects Of Food Quality On Growth And Carcass Composition In Lambs Of Two Breeds And Their Cross, R. M. Lewis, J. M. Macfarlane, G. Simm, G. C. Emmans

Department of Animal Science: Faculty Publications

The effects offood quality, breed type and sex (ram and ewe) on Iamb growth and carcass composition, and their changes throughout growth, were measured. The three breed typeswereScottish Blackface (B; no. = 24), Suffolk (S; no. = 28) and their reciprocal crosses (X; no. 33). The lambs had free access to a nutritionally non-limiting food, H, or a bulky food, L. Each lamb was scanned using X-ray computed tomography to measure the weights offat, lean and bone in the carcass at three degrees of maturity (0·30, 0·45 and 0·65) in live weight. Live weight and food intake data were recorded …

Effects Of Index Selection On The Performance And Carcass Composition Of Sheep Given Foods Of Different Protein Concentrations Ad Libitum., R. M. Lewis, G. C. Emmans, G. Simm

Department of Animal Science: Faculty Publications

Sheep of a line selected on an index to increase carcass lean content at 150 days of age (selected (S); no. = 90), and an unselected control line (control (C); no. = 90), were given ad libitum foods of three different protein concentrations (192, 141 and 120 g/kg dry matter). Growth was measured from about 21 to 114 kg live weight. The carcasses of each line were analysed for lean, fat and bone at three widely varying weights in both males and females. Level of protein did not affect the extent to tohidi S was superior to C in the …

Predicting Population Gene Frequency From Sample Data, R. M. Lewis, B. Grundy, L. A. Kuehn

Department of Animal Science: Faculty Publications

With an increase in the number of candidate genes for important traits in livestock, effective strategies for incorporating such genes into selection programmes are increasingly important. Those strategies in part depend on the frequency of a favoured allele in a population. Since comprehensive genotyping of a population is seldom possible, we investigate the consequences of sampling strategies on the reliability of the gene frequency estimate for a bi-allelic locus. Even within a subpopulation or line, often only a proportion of individuals will be genotype tested. However, through segregation analysis, probable genotypes can be assigned to individuals that themselves were not …

Exogenous Estrogen Boosts Circulating Estradiol Concentrations And Calcium Uptake By Duodenal Tissue In Heat-Stressed Hens, K.K. Hansen, M.M. Beck, S.E. Scheideler, Erin E. Blankenship

Department of Animal Science: Faculty Publications

In the hen, heat stress (HS) disrupts shell calcification and reproductive processes, including hormone synthesis and egg production. Two studies were conducted to investigate palliative effects of exogenous estrogen or dietary vitamin D3 on Ca homeostasis and reproductive physiology during HS. Study 1: Hy-Line W36 hens were randomly assigned to thermoneutral (TN) or HS treatments and to 1 of 7 estrogen treatments: zero (control) or one Compudose 200 implant given 1, 2, 3, 8, 9, or 10 d before onset of HS. With no implant, HS reduced plasma estradiol (E2) and total Ca absorbed (CaT) by duodenal cells (P < 0.05). In TN hens with implants, plasma E2 tripled within 24 h (P < 0.05) and remained elevated (P < 0.05) through d 9. In HS hens with implants, plasma E2 rose 6-fold (P < 0.05) to equal TN+E2 concentrations and remained elevated through d 10. In TN and HS hens with implants, the rate of Ca absorption (CaTR) and CaT increased dramatically; the responses were quadratic and essentially identical. Study 2: Hy-Line W36 hens were provided diets formulated either according to NRC requirements (NRC, 1994), or with the addition of 22,000 IU/kg vitamin D3 (+VD hens). A 24-h HS episode was imposed 2 wk after initiation of the dietary regimen. Duodenal samples were collected for Ca absorption assays after the 24-h HS episode. Both CaTR and CaT in +VD hens were approximately 3-fold higher than in hens in the NVD group (P = 0.102). The results lead to the conclusion that exogenous estrogen, high levels of dietary vitamin D, or both, before a HS episode, are efficacious in alleviating at least some of the effects of HS and should be further investigated.

National Pork Producers Council Maternal Line Genetic Evaluation: A Comparison Of Growth And Carcass Traits In Terminal Progeny, J. D. Cassady, O. W. Berg, Rodger K. Johnson, J. W. Mabry, L. L. Christian, M. D. Tokach, R. K. Miller, R. N. Goodwin

Department of Animal Science: Faculty Publications

The objective of this study was to compare growth and carcass traits of 1,252 progeny of six commercially available dam lines included in the National Pork Producers Council Maternal Line Evaluation Project. Lines compared included one maternal line supplied by each of American Diamond Swine Genetics (ADSG), Danbred NA (DB), two lines supplied by Monsanto Choice Genetics (DK and GPK347), Newsham Hybrids (NH), and Landrace × Large White females supplied by the National Swine Registry (NSR). All females were mated to DB, Duroc-Hampshire terminal sires. Traits analyzed were ADG from 56 to 115 kg live weight, days to 115 kg, …

New Alleles In Calpastatin Gene Are Associated With Meat Quality Traits In Pigs, Daniel C. Ciobanu, John W. M. Vleck, S. M. Lonergan, H. Thomsen, J. C. M. Dekkers, G. S. Plastows, M. F. Rothschild

Department of Animal Science: Faculty Publications

Suggestive QTL affecting raw firmness scores and average Instron force, tenderness, juiciness, and chewiness on cooked meat were mapped to pig chromosome 2 using a three-generation intercross between Berkshire and Yorkshire pigs. Based on its function and location, the calpastatin (CAST) gene was considered to be a good candidate for the observed effects. Several missense and silent mutations were identified in CAST and haplotypes covering most of the coding region were constructed and used for association analyses with meat quality traits. Results demonstrated that one CAST haplotype was significantly associated with lower Instron force and cooking loss and …

Effects Of Two Dried Forages, And A Choice Between Them, On Intake, Growth And Carcass Composition In Lambs Of Two Breeds And Their Cross, R. M. Lewis, J. M. Macfarlane, G. C. Emmans

Department of Animal Science: Faculty Publications

The effects of for age type, breed type and sex on lamb growth and carcass composition, and their changes throughout growth, were measured. The three breed types were Scottish Blackface (no. =31), Suffolk (no. =28) and their reciprocal cross (no. =30). The lambs were given ad libitum a pelleted rye grass alone, pelleted lucerne alone or a choice of both. Each lamb was scanned using X-ray computed tomography to measure the weights of fat, lean and bone in the carcass at three proportions of mature body weight (0-30, 0·45 and 0·65). Live weights and food intake data were recorded weekly. …

Soil Characterization Using Textural Features Extracted From Gpr Data, Lameck O. Odhiambo, Robert S. Wright, Ronald E. Yoder

Department of Animal Science: Faculty Publications

Soils can be non-intrusively mapped by observing similar patterns within ground-penetrating radar (GPR) profiles. We observed that the intricate and often indiscernible textural variability found within a complex GPR image possesses important parameters that help delineate regions of similar soil characteristics. Therefore, in this study, we examined the feasibility of using textural features extracted from GPR data to automate soil characterizations. The textural features were matched to a "fingerprint" database of previous soil classifications of GPR textural features and the corresponding ground truths of soil conditions. Four textural features (energy, contrast, entropy, and homogeneity) were selected for inputs into a …

Evaluation Of Procedures To Predict Fat-Free Lean In Swine Carcasses, Rodger K. Johnson, E. P. Johnson, R. Goodwin, J. W. Mabry, R. K. Miller, O. W. Robison, H. Sellers, M. D. Tokach

Department of Animal Science: Faculty Publications

The objectives were to develop equations for predicting fat-free lean in swine carcasses and to estimate the prediction bias that was due to genetic group, sex, and dietary lysine level. Barrows and gilts (n = 1,024) from four projects conducted by the National Pork Board were evaluated by six procedures, and their carcass fat-free lean was determined. Pigs of 16 genetic groups were fed within weight groups one of four dietary regimens that differed by 0.45% in lysine content and slaughtered at weights between 89 and 163 kg. Variables in equations included carcass weight and measures of backfat depth and …

Cd46-Mediated Transduction Of A Species D Adenovirus Vaccine Improves Mucosal Vaccine Efficacy, Zenaido T. Camacho, Mallory A. Turner, Michael A. Barry, Eric A. Weaver

Nebraska Center for Virology: Faculty Publications

The high levels of preexisting immunity against Adenovirus type 5 (Ad5) have deemed Ad5 unusable for translation as a human vaccine vector. Low seroprevalent alternative viral vectors may be less impacted by preexisting immunity, but they may also have significantly different phenotypes from that of Ad5. In this study we compare species D Ads (26, 28, and 48) to the species C Ad5. In vitro transduction studies show striking differences between the species C and D viruses. Most notably, Ad26 transduced human dendritic cells much more effectively than Ad5. In vivo imaging studies showed strikingly different transgene expression profiles. The …

Phylogenetic Analyses Of Texas Isolates Indicate An Evolving Subtype Of The Clade B Feline Immunodeficiency Viruses, Eric A. Weaver, Ellen W. Collisson, Margaret Slater, Guan Zhu

Nebraska Center for Virology: Faculty Publications

Rigorous phylogenetic analyses were used to compare the nucleotide sequences of feline immunodeficiency virus strains isolated from Texas and throughout the world. The envelope V3-V4 sequences and capsid gene of the Texas isolates formed a cluster between subtypes B and E. Statistical comparisons with other published sequences confirmed that the Texas group is a unique cluster, possibly a new subtype, arising from subtype B.