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Selection

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Full-Text Articles in Life Sciences

A Game Theoretic Approach To Design Mating Programs For Livestock, Ebru Ergüneş Berki̇n, Hasan Önder, Özgür Hakan Aydoğmuş Jan 2022

A Game Theoretic Approach To Design Mating Programs For Livestock, Ebru Ergüneş Berki̇n, Hasan Önder, Özgür Hakan Aydoğmuş

Turkish Journal of Veterinary & Animal Sciences

In this study, we proposed a new game theoretic method to design a mating program. The index and game theoretic methods were applied with calculated breeding values using pedigree on two different data sets whose economic traits consist of negative (milk yield and fat percentage) and positive (birth and weaning weight) genetic correlated data. For the negative genetic correlated data set, even if total expected benefits were equal for two methods, mating programs were changed, and the coefficient of variation obtained using the game theoretic method was smaller than that of the index method. This result showed that the expected …


Productive Performance, Egg Quality, And Hatching Traits Of Japanese Quail Lines Selectedfor Higher Body Weight And Egg Number, Abdur Rehman, Jibran Hussain, Athar Mahmud, Khalid Javed, Abdul Ghayas, Sohail Ahmad Jan 2022

Productive Performance, Egg Quality, And Hatching Traits Of Japanese Quail Lines Selectedfor Higher Body Weight And Egg Number, Abdur Rehman, Jibran Hussain, Athar Mahmud, Khalid Javed, Abdul Ghayas, Sohail Ahmad

Turkish Journal of Veterinary & Animal Sciences

The present study evaluated the effect of selection for higher body weight (weight based selection = WBS) and egg numbers (egg based selection = EBS) on productivity, egg quality, and hatching traits of Japanese quail for three generations. From a base population of 1125 day-old chicks of Japanese quail, best performing families were allowed to propagate for getting next generation. WBS in G3 presented higher values of feed intake, egg weight, hatching weight. However, egg production and feed conversion ratio were better in EBS during G3. The incidence of embryonic mortality was also lower in the WBS line. In the …


Display Site Selection By Male Ruffed Grouse In The Upper Great Lakes Region, Seth Finkel Jan 2022

Display Site Selection By Male Ruffed Grouse In The Upper Great Lakes Region, Seth Finkel

Dissertations, Master's Theses and Master's Reports

The Ruffed Grouse (Bonasa umbellus) is widely known for its characteristic territorial drumming display. In this study, I used ruffed grouse drumming survey data from Minnesota and Michigan, in a series of mixed logistic models, to identify drivers of drumming log selection by reproductive male ruffed grouse. I collected drumming stage data utilizing a paired-random sampling structure. I used information theoretic model selection to examine three sets of a priori mixed logistic models: one for the entirety of my Minnesota dataset, one consisting of stages identified in aspen stands in Minnesota, and one for my Michigan dataset. In …


Effects Of Different Selection Strategies On Subsequent Breeder Performance, Slaughter,And Carcass Traits Of Japanese Quail, Sohail Ahmad, Jibran Hussain, Hafiz Muhammad Ishaq, Athar Mahmud, Shahid Sherzada, Muhammad Usman, Abdur Rehman, Muhammad Zaid Jan 2021

Effects Of Different Selection Strategies On Subsequent Breeder Performance, Slaughter,And Carcass Traits Of Japanese Quail, Sohail Ahmad, Jibran Hussain, Hafiz Muhammad Ishaq, Athar Mahmud, Shahid Sherzada, Muhammad Usman, Abdur Rehman, Muhammad Zaid

Turkish Journal of Veterinary & Animal Sciences

The present study evaluated the effect of different selection strategies in four closebred flocks (CBF) at three ages on subsequent breeder performance and carcass traits. A total of 540 Japanese quails already selected for higher body weight from four CBF (Major, Kaleem, Saadat, and Zahid) at three ages (10, 12, and 14 weeks) were subjected to 3 selection strategies (i.e. pedigree, mass selection, and randombred control). In pedigree selection, 108 birds with higher body weight were selected with full pedigree record whereas, in the mass selection, 324 birds with higher body weight were selected to be the parents of the …


Associations Of Snps In Ghr Gene With Growth And Milk Yield Of Anatolian Buffaloes, Meti̇n Erdoğan, Mustafa Tekerli̇, Koray Çeli̇keloğlu, Özlem Hacan, Serdar Koçak, Zehra Bozkurt, Samet Çi̇nkaya, Mustafa Demi̇rtaş Jan 2021

Associations Of Snps In Ghr Gene With Growth And Milk Yield Of Anatolian Buffaloes, Meti̇n Erdoğan, Mustafa Tekerli̇, Koray Çeli̇keloğlu, Özlem Hacan, Serdar Koçak, Zehra Bozkurt, Samet Çi̇nkaya, Mustafa Demi̇rtaş

Turkish Journal of Veterinary & Animal Sciences

This study was carried out to investigate the associations between single nucleotide polymorphisms (SNP) in the growth hormone receptor (GHR) gene and growth and milk yields of Anatolian buffaloes. Growth records of genotyped 3012 Anatolian buffaloes and 467 lactations of 329 cows from them were used. The overall means of weights at birth, six and 12 months of ages and lactation milk yield were 29.377 ± 0.342 kg, 96.15 ± 1.48 kg, 165.54 ± 2.18 kg, and 976.3 ± 39.9 kg, respectively. Three mutations (g.31601787 G > A, g.31601784 G > A, and g.31601783 G > del) in GHR were detected. A least-squares …


Genomic Adaptations To Salinity Resist Gene Flow In The Evolution Of Floridian Watersnakes, Rhett M. Rautsaw, Tristan D. Schramer, Rachel Acuña, Lindsay N. Arick, Mark Dimeo, Kathryn P. Mercier, Michael Schrum, Andrew J. Mason, Mark J. Margres, Jason L. Strickland, Christopher L. Parkinson Oct 2020

Genomic Adaptations To Salinity Resist Gene Flow In The Evolution Of Floridian Watersnakes, Rhett M. Rautsaw, Tristan D. Schramer, Rachel Acuña, Lindsay N. Arick, Mark Dimeo, Kathryn P. Mercier, Michael Schrum, Andrew J. Mason, Mark J. Margres, Jason L. Strickland, Christopher L. Parkinson

Publications and Research

The migration-selection balance often governs the evolution of lineages, and speciation with gene flow is now considered common across the tree of life. Ecological speciation is a process that can facilitate divergence despite gene flow due to strong selective pressures caused by ecological differences; however, the exact traits under selection are often unknown. The transition from freshwater to saltwater habitats provides strong selection targeting traits with osmoregulatory function. Several lineages of North American watersnakes (Nerodia spp.) are known to occur in saltwater habitat and represent a useful system for studying speciation by providing an opportunity to investigate gene flow …


Starvation Resistance Is Associated With Developmentally Specified Changes In Sleep, Feeding And Metabolic Rate, Elizabeth B. Brown, Melissa E. Slocumb, Milan Szuperak, Arianna Kerbs, Allen G. Gibbs, Matthew S. Kayser, Alex C. Keene Feb 2019

Starvation Resistance Is Associated With Developmentally Specified Changes In Sleep, Feeding And Metabolic Rate, Elizabeth B. Brown, Melissa E. Slocumb, Milan Szuperak, Arianna Kerbs, Allen G. Gibbs, Matthew S. Kayser, Alex C. Keene

Life Sciences Faculty Research

Food shortage represents a primary challenge to survival, and animals have adapted diverse developmental, physiological and behavioral strategies to survive when food becomes unavailable. Starvation resistance is strongly influenced by ecological and evolutionary history, yet the genetic basis for the evolution of starvation resistance remains poorly understood. The fruit fly Drosophila melanogaster provides a powerful model for leveraging experimental evolution to investigate traits associated with starvation resistance. While control populations only live a few days without food, selection for starvation resistance results in populations that can survive weeks. We have previously shown that selection for starvation resistance results in increased …


Performance Differences Between Two Groups Of Commercial Pigs Following Experimental Infection With Prrs Virus 1-7-4, Erin Little Jan 2019

Performance Differences Between Two Groups Of Commercial Pigs Following Experimental Infection With Prrs Virus 1-7-4, Erin Little

Electronic Theses and Dissertations

Porcine reproductive and respiratory syndrome virus (PRRSV) is the costliest swine disease in North America. Vaccines and management alone have not been effective in controlling this disease. Genetic selection for resilience may be a complimentary approach for controlling PRRSV. The objective of this study was to estimate performance differences between two groups of pigs from the same commercial line following infection with PRRSV 1-7-4: 1) pigs sired by boars selected based on a standard index (TN-S), which emphasized feed efficiency and carcass quality; and 2) pigs sired by boars selected based on an experimental index (TN-E), which emphasized feed intake, …


Correlations Between Egg Weight, Early Embryonic Development, And Some Hatching Characteristics Of Japanese Quail (Coturnix Japonica), Beata Grzegrzó?Ka, Joanna Gruszczy?Ska Jan 2019

Correlations Between Egg Weight, Early Embryonic Development, And Some Hatching Characteristics Of Japanese Quail (Coturnix Japonica), Beata Grzegrzó?Ka, Joanna Gruszczy?Ska

Turkish Journal of Veterinary & Animal Sciences

The correlations between selected egg, embryo development, and chick traits were analyzed in three lines of Japanese quail subjected to intrafamily selection for 28th day body weight (group S) and in three lines of random control birds (group K). The significant correlation coefficients between egg weight and most of the traits observed after the first two days of incubation as well as chick weight and shank length were estimated. Most of the correlations obtained were significant in both groups. No statistically significant differences between groups were confirmed, but there was a lines effect within the groups in most cases and …


The Spatial Ecology And Microhabitat Selection Of The Pygmy Rattlesnake (Sistrurus Miliarius) In Southwestern Missouri, Dylan Wallace Maag Dec 2017

The Spatial Ecology And Microhabitat Selection Of The Pygmy Rattlesnake (Sistrurus Miliarius) In Southwestern Missouri, Dylan Wallace Maag

MSU Graduate Theses

Despite a wide distribution throughout the southeastern United States, pygmy rattlesnakes (Sistrurus miliarius) have received less research attention than many other rattlesnake species. I captured a total of 33 S. miliarius at the Drury-Mincy Conservation Area (DMCA) and retained 14 large individuals (mostly gravid females) for a radio telemetry study. Snakes were primarily captured during evening road driving surveys and were encountered rarely with any other sampling technique. Sistrurus miliarius are widespread at DMCA where they were encountered in forest, savanna, and glade habitats. Snakes selected microhabitats with more vegetative cover and tree canopy closure than random sites …


Subjective Experience In Insects: Definitions And Other Difficulties, Shelley Adamo Aug 2016

Subjective Experience In Insects: Definitions And Other Difficulties, Shelley Adamo

Animal Sentience

Whether insects have the potential for subjective experiences depends on the definition of subjective experience. The definition used by Klein & Barron (2016) is an unusually liberal one and could be used to argue that some modern robots have subjective experiences. From an evolutionary perspective, the additional neurons needed to produce subjective experiences will be proportionately more expensive for insects than for mammals because of the small size of the insect brain. This greater cost could weaken selection for such traits. Minimally, it may be premature to assume that small neuronal number is unimportant in determining the capacity for consciousness.


Characterization Of Broiler Lines Divergently Selected For Breast Muscle Color, Sara Katherine Orlowski Aug 2016

Characterization Of Broiler Lines Divergently Selected For Breast Muscle Color, Sara Katherine Orlowski

Graduate Theses and Dissertations

An increase in the consumption of poultry has generated an increase in demand for higher yielding broilers. This has led to an increase in atypical meat and issues with appearance. Color is a direct result of a pH decline as meat goes through rigor mortis with meat generally becoming lighter. If the pH declines too rapidly or too slowly, meat quality can suffer. Physical properties of meat can be altered by pH. A fast pH decline results in pale meat with decreased tenderness. A slow pH decline can result in darker meat with a reduced shelf-life. With a known relationship …


Productivity And Adaptation Ability Of Holstein Cattle Of Different Genetic Selections, Ivan Fiodorovich Gorlov, Svetlana Evgenievna Bozhkova, Olga Pavlovna Shakhbazova, Vera Vasilievna Gubareva, Natali Ivanovna Mosolova, Elena Yurievna Zlobina, Yuriy Nicolaevich Fiodorov, Alexey Sergeevich Mokhov Jan 2016

Productivity And Adaptation Ability Of Holstein Cattle Of Different Genetic Selections, Ivan Fiodorovich Gorlov, Svetlana Evgenievna Bozhkova, Olga Pavlovna Shakhbazova, Vera Vasilievna Gubareva, Natali Ivanovna Mosolova, Elena Yurievna Zlobina, Yuriy Nicolaevich Fiodorov, Alexey Sergeevich Mokhov

Turkish Journal of Veterinary & Animal Sciences

The purpose of the research was to compare economically useful traits of Holstein cows of different selections. The results show that the German and Australian selections were superior to the Danish and American cows in terms of their growth (at 36 months of age, the body weights of the German and Australian cows were 36.5 and 27.6 kg greater than the Danish cows and 24.3 and 15.4 kg greater than the American cows, respectively). Maximum milk yield was obtained from the American and German cows (25,220 and 24,861 kg). Their milk also had higher fat content. The maximum protein content …


Breeding Objectives Indicate Value Of Genomics For Beef Cattle, M. D. Macneil Jan 2016

Breeding Objectives Indicate Value Of Genomics For Beef Cattle, M. D. Macneil

Kansas Agricultural Experiment Station Research Reports

Genomics may have much to offer in the implementation of breeding objectives. Advantages of genomic prediction include increased accuracy of expected progeny differences (EPDs) for traits that have been components of routine genetic evaluations. Perhaps more importantly, genomic prediction makes it possible to include traits that are too costly or too difficult to measure, and traits that are measured too late in life or are sex-limited such that candidates for selection cannot have EBV with high accuracy at the time when selection decisions are made. Genomically enhanced EPDs may also allow for a marked reduction in generation interval, thus accelerating …


Correlated Response To Selection And Effects Of Pre-Slaughter Environment On Meat Quality In Broilers Divergently Selected For Muscle Color, Isaac David Harford Aug 2014

Correlated Response To Selection And Effects Of Pre-Slaughter Environment On Meat Quality In Broilers Divergently Selected For Muscle Color, Isaac David Harford

Graduate Theses and Dissertations

Two broiler lines divergently selected for high (HMC) and low (LMC) muscle lightness (L*) were formed from a random bred control line (RBC). After eight generations of selection, three experimental trials were conducted to investigate the correlated response to selection and effects of pre-slaughter environment on meat quality in all three lines.

In the first experiment, a total of 100 birds from each line were bled for blood chemistry analysis and were evaluated for meat quality the following day. The HMC line had higher fillet drip loss (DL), L*, heterophil to lymphocyte ratio (H:L), and platelet count (Plt), and lower …


Single-Nucleotide Polymorphisms Associated With Performance Traits In Beef Cattle Grazing Endophyte-Infected Tall Fescue, Bryan Christopher Bastin Aug 2013

Single-Nucleotide Polymorphisms Associated With Performance Traits In Beef Cattle Grazing Endophyte-Infected Tall Fescue, Bryan Christopher Bastin

Masters Theses

Tall fescue (Lolium arundinaceum Schreb.) is the most prevalent forage in the Midsouth United States due in part to the presence of the endophytic fungus Neotyphodium coenophialum. The fungus, while conferring hardiness to tall fescue, contributes to decreased production efficiency in cow-calf operations. A previous genome-wide association study was performed using the Illumina 50k bovine SNP chip. Twenty-four SNP were found to be associated (P < 0.05) with adjusted birth weight and adjusted 205-day weights of calves from 48 beef cows at Ames Plantation. The first objective was to validate each SNP by testing associations with several additional phenotypes. Custom Taqman genotyping assays (Applied Biosystems, Foster City, CA) were subsequently designed to genotype each SNP in beef cattle located at Tennessee Tech University (n = 654), to validate associations in a large, independent herd. The results yielded 15 associations that were significant (P < 0.05) with 6 phenotypes linked to those affected by fescue toxicosis. The second objective investigated the link between fescue toxicosis and the XK, Kell blood group complex subunit-related, member 4 …


Different Modes Of Evolution In Males And Females Generate Dichromatism In Fairy-Wrens (Maluridae), Allison E. Johnson, J. Jordan Price, Stephen Pruett-Jones Jan 2013

Different Modes Of Evolution In Males And Females Generate Dichromatism In Fairy-Wrens (Maluridae), Allison E. Johnson, J. Jordan Price, Stephen Pruett-Jones

School of Biological Sciences: Faculty Publications

Sexual dichromatism in birds is often attributed to selection for elaboration in males. However, evolutionary changes in either sex can result in plumage differences between them, and such changes can result in either gains or losses of dimorphism. We reconstructed the evolution of plumage colors in both males and females of species in Maluridae, a family comprising the fairy-wrens (Malurus, Clytomias, Sipodotus), emu-wrens (Stipiturus), and grasswrens (Amytornis). Our results show that, across species, males and females differ in their patterns of color evolution. Male plumage has diverged at relatively steady rates, whereas …


Semen Quality In White Leghorn Chicken Selected For Egg Production Traits, Shanmugam Murugesan, Niranjan Matam, Rakesh Kulkarni, Tarun Kumar Bhattacharya, Rudranath Chatterjee Jan 2013

Semen Quality In White Leghorn Chicken Selected For Egg Production Traits, Shanmugam Murugesan, Niranjan Matam, Rakesh Kulkarni, Tarun Kumar Bhattacharya, Rudranath Chatterjee

Turkish Journal of Veterinary & Animal Sciences

The present study was conducted to evaluate the effect of selection for egg production traits in White Leghorn chicken based upon the semen quality. Males of 3 pure lines of White Leghorn, namely IWH, IWI, and IWK, along with a pedigree random-bred control (IWC) population, were selected and housed in individual cages. The semen collected from individual birds was evaluated for different physical and biochemical parameters. There was significant (P =< 0.013) difference in semen quality parameters studied between the lines. High egg-producing lines IWH and IWI had poor semen quality in comparison with that of the control line (IWC). Thus, it can be concluded that selection for higher egg production affects the semen quality of males in the selected lines.


Observations Of Oviposition Behavior Among North American Tiger Beetle (Coleoptera: Carabidae: Cicindelinae) Species And Notes On Mass Rearing, Mathew L. Brust, C. Barry Knisley, Stephen M. Spomer, Kentaro Miwa Jan 2012

Observations Of Oviposition Behavior Among North American Tiger Beetle (Coleoptera: Carabidae: Cicindelinae) Species And Notes On Mass Rearing, Mathew L. Brust, C. Barry Knisley, Stephen M. Spomer, Kentaro Miwa

University of Nebraska State Museum: Entomology Papers

Although the larvae of a large number of North American tiger beetle species have been described, little information exists on the oviposition behavior of female tiger beetles at the species level. In this study, we found that the oviposition behavior varied widely among species, with some species utilizing more than one method. We found that, contrary to many references, several tiger beetle species did not oviposit from above the soil surface by inserting the ovipositor into the soil. Instead, several species oviposited by tunneling over 20 mm below the soil surface. In addition, we outline recently used successful protocols for …


Prediction Of Genetic Values For Feed Intake From Individual Body Weight Gain And Total Feed Intake Of The Pen, A. J. Cooper, Calvin Ferrell, Larry V. Cundiff, L. D. Van Vleck Jan 2010

Prediction Of Genetic Values For Feed Intake From Individual Body Weight Gain And Total Feed Intake Of The Pen, A. J. Cooper, Calvin Ferrell, Larry V. Cundiff, L. D. Van Vleck

Department of Animal Science: Faculty Publications

Records of individual feed intake (FI) and BW gain (GN) were obtained from the Germ Plasm Evaluation (GPE) program at US Meat Animal Research Center (USMARC). Animals were randomly assigned to pens. Only pens with 6 to 9 steers (n = 289) were used for this study (data set 1). Variance components and genetic parameters were estimated using data set 1. Estimated genetic values (EGV) for FI were calculated by 5 methods using single and 2-trait analyses: 1) individual FI and individual GN, 2) individual FI alone, 3) 2-trait with individual GN but with FI missing, 4) individual GN and …


Feed Intake Of Sheep As Affected By Body Weight, Breed, Sex, And Feed Composition, R. M. Lewis, G. C. Emmans Jan 2010

Feed Intake Of Sheep As Affected By Body Weight, Breed, Sex, And Feed Composition, R. M. Lewis, G. C. Emmans

Department of Animal Science: Faculty Publications

The hypotheses tested were that genetic size-scaling for mature BW (A, kg) would reduce variation in intake between kinds of sheep and that quadratic polynomials on u = BW/A with zero intercept would provide good descriptions of the relationship between scaled intake (SI, g/A0.73 d) and degree of maturity in BW (u) across feeds of differing quality. Both sexes of Suffolk sheep from 2 experimental lines (n = 225) and from 3 breed types (Suffolk, Scottish Blackface, and their cross; n = 149) were recorded weekly for ad libitum feed intake and BW; recording of intake was from weaning through, …


Selecting, Marketing And Rebuilding A Herd Of Genetically Superior Animals, Katherine Rector Dec 2009

Selecting, Marketing And Rebuilding A Herd Of Genetically Superior Animals, Katherine Rector

Dairy Science

No abstract provided.


Sheep Updates 2008 - Part 3, L. J. E. Karlsson, J. C. Greeff, L. Slocombe, K. Jones, N. Underwood, Fred Wilkinson, W. D. Hoffman, W. A. Mckiernan, V. H. Oddy, M. J. Mcphee, B. L. Mcintyre, P. F. Parnell, R. A. Clark, J. Timms, G. Griffith, C. Mulholland, P. Hyland, Danielle England, Fiona Jones, John Lucey, Martin Staines, Richard Morris, Megan Abrahams, Caroline Peek, Dennis Van Gool, Daniel Gardiner, Kari-Lee Falconer, Sandra Prosser, Mario D'Antuono, John Young, Andrew Thompson, Chris Oldham, Brown Besier, Angus Campbell, Ralph Behrendt Jul 2008

Sheep Updates 2008 - Part 3, L. J. E. Karlsson, J. C. Greeff, L. Slocombe, K. Jones, N. Underwood, Fred Wilkinson, W. D. Hoffman, W. A. Mckiernan, V. H. Oddy, M. J. Mcphee, B. L. Mcintyre, P. F. Parnell, R. A. Clark, J. Timms, G. Griffith, C. Mulholland, P. Hyland, Danielle England, Fiona Jones, John Lucey, Martin Staines, Richard Morris, Megan Abrahams, Caroline Peek, Dennis Van Gool, Daniel Gardiner, Kari-Lee Falconer, Sandra Prosser, Mario D'Antuono, John Young, Andrew Thompson, Chris Oldham, Brown Besier, Angus Campbell, Ralph Behrendt

Sheep Updates

This session covers fiveteen papers from different authors:

CONTROLLING FLY STRIKE

1. Breeding for Blowfly Resistance - Indicatoe Traits, LJE Karlsson, JC Greeff, L Slocombe, Department of Agriculture & Food, Western Australia

2.A practical method to select for breech strike resistance in non-pedigreed Merino flocks, LJE Karlsson, JC Greeff, L Slocombe, K. Jones, N. Underwood, Department of Agriculture & Food, Western Australia

3. Twice a year shearing - no mulesing, Fred Wilkinson, Producer, Brookton WA

BEEF

4. Commercial testing of a new tool for prediction of fatness in beef cattle, WD HoffmanA, WA McKiernanA, VH Oddy …


Bovine Respiratory Disease In Feedlot Cattle: Phenotypic, Environmental, And Genetic Correlations With Growth, Carcass, And Longissimus Muscle Palatability Traits, G. D. Snowder, L. Dale Van Vleck, L. V. Cundiff, G. L. Bennett, M. Koohmaraie, M. E. Dikeman Jul 2007

Bovine Respiratory Disease In Feedlot Cattle: Phenotypic, Environmental, And Genetic Correlations With Growth, Carcass, And Longissimus Muscle Palatability Traits, G. D. Snowder, L. Dale Van Vleck, L. V. Cundiff, G. L. Bennett, M. Koohmaraie, M. E. Dikeman

Department of Animal Science: Faculty Publications

Bovine respiratory disease (BRD) is the most costly feedlot disease in the United States. Selection for disease resistance is one of several possible interventions to prevent or reduce the economic loss associated with animal disease and to improve animal welfare. Undesirable genetic relationships, however, may exist between production and disease resistance traits. The objectives of this study were to estimate the phenotypic, environmental, and genetic correlations of BRD with growth, carcass, and LM palatability traits. Health records on 18,112 feedlot cattle over a 15-yr period and slaughter data on 1,627 steers over a 4-yr period were analyzed with bivariate animal …


Comparison Of Feed Energy Costs Of Maintenance, Lean Deposition, And Fat Deposition In Three Lines Of Mice Selected For Heat Loss, D. L. Eggert, Merlyn K. Nielsen Jan 2006

Comparison Of Feed Energy Costs Of Maintenance, Lean Deposition, And Fat Deposition In Three Lines Of Mice Selected For Heat Loss, D. L. Eggert, Merlyn K. Nielsen

Department of Animal Science: Faculty Publications

Three replications of mouse selection populations for high heat loss (MH), low heat loss (ML), and a nonselected control (MC) were used to estimate the feed energy costs of maintenance and gain and to test whether selection had changed these costs. At 21 and 49 d of age, mice were weighed and subjected to dual x-ray densitometry measurement for prediction of body composition. At 21 d, mice were randomly assigned to an ad libitum, an 80% of ad libitum, or a 60% of ad libitum feeding group for 28-d collection of individual feed intake. Data were analyzed using 3 approaches. …


Correlated Responses In Maternal Performance Following Divergent Selection For Heat Loss In Mice, J. M. Mcdonald, Merlyn . K. Nielsen Jan 2006

Correlated Responses In Maternal Performance Following Divergent Selection For Heat Loss In Mice, J. M. Mcdonald, Merlyn . K. Nielsen

Department of Animal Science: Faculty Publications

Divergent selection in mice was applied in 3 independent replicates for high (maintenance high; MH) and low (maintenance low; ML) heat loss for 16 generations. An unselected control (maintenance control; MC) was also maintained in all replicates. Selection ceased for 26 generations; heat-loss measurement and selection resumed at generation 42. Lactation performance, dam weight, dam feed intake, and efficiency of production of pup weight were recorded or calculated for MH and ML dams in all 3 replicates at generation 46 or 47 with the objective of determining whether selection for heat loss has created correlated responses in maternal performance. One-half …


Incidence Of Splayleg Pigs In Nebraska Litter Size Selection Lines, J. W. Holl, R. K. Johnson Oct 2005

Incidence Of Splayleg Pigs In Nebraska Litter Size Selection Lines, J. W. Holl, R. K. Johnson

Department of Animal Science: Faculty Publications

Genetic parameters for the splayleg (SL) condition were estimated from 37,673 records of pigs from six lines derived from a Large White–Landrace base population. Random selection for 22 generations was practiced in Lines C1 and C2. Line C2 was derived from C1 at Generation 8. Selection lines were as follows: 1) Line I, selected 11 generations for an index of ovulation rate and embryonic survival followed by 11 generations of selection for litter size; 2) Line IOL, derived from Line I at Generation 8 and which underwent eight generations of two-stage selection for ovulation rate and number of fully formed …


Genetic Parameters For Stayability, Stayability At Calving, And Stayability At Weaning To Specified Ages For Hereford Cows, G. E. Martinez, R. M. Koch, L. V. Cundiff, K. E. Gregory, Stephen D. Kachman, L. Dale Van Vleck Aug 2005

Genetic Parameters For Stayability, Stayability At Calving, And Stayability At Weaning To Specified Ages For Hereford Cows, G. E. Martinez, R. M. Koch, L. V. Cundiff, K. E. Gregory, Stephen D. Kachman, L. Dale Van Vleck

Department of Animal Science: Faculty Publications

Genetic parameters for stayability to six ages (ST1, . . ., ST6), for five measures of stayability to calving (SC2, . . ., SC6), and for five measures of stayability to weaning (SW2, . . ., SW6), were estimated using records of 2,019 Hereford cows collected from 1964 to 1979 from a selection experiment with a control line and three lines selected for weaning weight, yearling weight, and an index of yearling weight and muscle score. The model included birth year of the cow as a fixed effect and the cow’s sire as a random effect. Analyses were performed with …


Sheep Updates 2005 - Part 1, R. W. Kelly, R. Kingwell, A. R. Bray, Chris Oldham, Graeme Martin, D. Blanche, D. Ferguson, Keith Crocker, Di Evans Jul 2005

Sheep Updates 2005 - Part 1, R. W. Kelly, R. Kingwell, A. R. Bray, Chris Oldham, Graeme Martin, D. Blanche, D. Ferguson, Keith Crocker, Di Evans

Sheep Updates

This session covers seven papers from different authors: Boosting lambing percentages of WA sheep flocks. R.W. Kelly CSIRO Livestock Industries, Floreat WA , R. Kingwell Department of Agriculture WA, Kiwis can fly - 30% higher lambing in 15 years, AR Bray, Meat and Wool New Zealand, Wellington, New Zealand Rams are not a trivial expense, so what can you do to maximise on your investment? Chri Oldham, Department of Agriculture Western Australia, Graeme Martin, University of West Australia. Care for mun - fetal programming, lamb survival and lifetime performance. RW Kelly CSIRO Livestock Industries, Floreat WA Boost lamb survival - …


Genetic Relationships Between Male And Female Reproductive Traits In Beef Cattle, G. Gargantini, L. V. Cundiff, D. D. Lunstra, L. D. Van Vleck Jan 2005

Genetic Relationships Between Male And Female Reproductive Traits In Beef Cattle, G. Gargantini, L. V. Cundiff, D. D. Lunstra, L. D. Van Vleck

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

Reproductive traits were measured for 234 bulls and 1184 heifers from matings of three dam breeds (Angus, Hereford, and U.S. Meat Animal Research Center III) with six sire breeds (Angus, Hereford, Brahman, Boran, Tuli, and Belgian Blue) from the Germ Plasm Evaluation (GPE) Program at Roman L. Hruska US Meat Animal Research Center. Male traits were yearling scrotal circumference (YSC), height (YH), and yearling BW; age at puberty (AP1; production of 50 million sperm with ≥10% progressive motility); age, scrotal circumference, average testis length, and testicular volume when 500 million sperm were …