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Utilization Of Pork And Pork By-Products For Nutritional And Behavioral Management Of Captive Exotic Felids, Cayla Jo Iske Jan 2015

Utilization Of Pork And Pork By-Products For Nutritional And Behavioral Management Of Captive Exotic Felids, Cayla Jo Iske

Graduate Theses and Dissertations

Currently two protein sources (beef or horse) comprise the majority of raw meat diet formulations for exotic carnivores in zoological institutions. Pork-based diets have traditionally not been fed to managed exotic carnivores, primarily because of microbial and pathogenic concerns, and nutrient digestibility of pork has not been evaluated in captive exotic carnivores, such as felids. Additionally, commercially prepared raw meat diets, while nutritionally complete, rarely meet nonnutritive requirements of cats, such as locating, capturing, and killing prey as well as psychological aspects related to the feeding process, and oral health needs. The pork industry currently sends many by-products to rendering ...


Comparison Of Piglet Birth Weight Classes, Parity Of The Dam, Number Born Alive And The Relationship With Litter Variation And Piglet Survival Until Weaning, Gregory Thomas Krahn Jan 2015

Comparison Of Piglet Birth Weight Classes, Parity Of The Dam, Number Born Alive And The Relationship With Litter Variation And Piglet Survival Until Weaning, Gregory Thomas Krahn

Graduate Theses and Dissertations

The objectives of this study was to determine the relationship between individual piglet birth weight and the odds of survival until weaning and differences due to sow parity. Piglets in this study were purebred Yorkshire (n=70763), purebred Landrace (n=51091), purebred Duroc (n=16834), and Landrace x Yorkshire or Yorkshire x Landrace (n=38447) reciprocal F1 piglets. Data were recorded from sows in four production units within the same genetic flow from September 2009 through November 2013. Piglets were individually weighed and identified within 24 hours of birth and cross-fostering was completed within 48 hours of birth. Survival was ...


Evaluation Of Algae Meal As A Novel Feedstuff For Ruminants, Rebecca Sue Stokes Jan 2015

Evaluation Of Algae Meal As A Novel Feedstuff For Ruminants, Rebecca Sue Stokes

Graduate Theses and Dissertations

Recent advances in technology support the use of heterotrophic microalgae for the production of oils for bioenergy. Oil is extracted and the resultant product includes a combination of both partially deoiled microalgae (PDM) and soyhulls, resulting in an algae meal (ALG) with a unique profile of protein, fiber, and fat. However, this novel feedstuff and the role it may play in the ruminant diet has not been previously characterized. Since PDM is not available commercially to producers separate from soyhulls, the whole product was used for the current research. Thus, the ensuing research trials were designed to: 1) determine the ...


Effects Of Heat Stress Or Ketosis On Metabolism And Inflammatory Biomarkers In Ruminants And Monogastrics, Mohannad Khaled Ali Abuajamieh Jan 2015

Effects Of Heat Stress Or Ketosis On Metabolism And Inflammatory Biomarkers In Ruminants And Monogastrics, Mohannad Khaled Ali Abuajamieh

Graduate Theses and Dissertations

There are several constraints to of the sustainability of the livestock industries in different areas of the world. The two most obvious hurdles to high dairy production are diseases during the transition period and heat stress (HS). Despite decades of research, the actual pathologies of ketosis and HS remain poorly understood. In the US, it was estimated that the economic losses from ketosis is $360/cow/cycle, and to HS was ~ $900 million per year. Thus, both severely jeopardize the competitiveness of animal agriculture. Regardless of the herd size, HS and ketosis affect every dairy region in the country. The ...


Changing Distillers Grains: Implications For Cattle Performance And Management, Erika Linn Lundy Jan 2015

Changing Distillers Grains: Implications For Cattle Performance And Management, Erika Linn Lundy

Graduate Theses and Dissertations

In the past decade, the ethanol industry has begun changing their production processes to capture more value from the corn kernel, altering the nutrient profile of distillers grains (DG). One of the first methods of value extraction includes partial removal of corn oil, resulting in a decreased oil or fat content of DG. Although the majority of ethanol plants are currently extracting oil from DG, limited research has been conducted regarding the use of new generation DG in finishing cattle diets. Previous research with decreased fat DG has shown varying results in cattle performance when compared to traditional DG. The ...


Impact Of Prrs And Ped Viruses On Grower Pig Performance And Intestinal Function, Wesley Paul Schweer Jan 2015

Impact Of Prrs And Ped Viruses On Grower Pig Performance And Intestinal Function, Wesley Paul Schweer

Graduate Theses and Dissertations

Porcine reproductive and respiratory syndrome (PRRSV) and porcine epidemic diarrhea (PEDV) viruses are two of the most economically significant diseases to affect the U.S. swine industry today. Yet, little is known about how they impact pig nutrient digestibility, intestinal function and feed efficiency. Therefore, the overall objective of this thesis was to determine the impact of PRRSV and PEDV viruses, alone or in combination, on grower pig performance, tissue accretion and on intestinal function and integrity. To accomplish these objectives, a series of experiments were conducted and are outlined in three research chapters (Chapter 2, 3 and 4). In ...


Evaluating The Ability Of The Ne System To Predict Growth Performance And Energy Utilization Of Growing Pigs, Jesus Alberto Acosta Camargo Jan 2015

Evaluating The Ability Of The Ne System To Predict Growth Performance And Energy Utilization Of Growing Pigs, Jesus Alberto Acosta Camargo

Graduate Theses and Dissertations

The net energy (NE) system describes the useful energy for growth better than the metabolizable energy (ME) system. Therefore, the NE system should demonstrate a more predictable animal response when a wide range of ingredients are used, but this fact needs to be demonstrated in practice. The objective of this thesis was to evaluate the NE system in diets containing a diverse set of ingredients. Two experiments were conducted: the first experiment consisted of comparing growth performance, carcass characteristics and the efficiency of dietary energy of 2,054 pigs housed in pens in a commercial research barn. Pens were assigned ...


Enhancing Botanical Composition, Wildlife Habitat And Carbon Sequestration Of Pastures In South Central Iowa Through Soil Disturbance By Mob Grazing Of Beef Cattle, James R. Russell, Harris J. Sellers, Stephen Barnhart, Daniel G. Morrical, Helga Offenburger Jan 2015

Enhancing Botanical Composition, Wildlife Habitat And Carbon Sequestration Of Pastures In South Central Iowa Through Soil Disturbance By Mob Grazing Of Beef Cattle, James R. Russell, Harris J. Sellers, Stephen Barnhart, Daniel G. Morrical, Helga Offenburger

Leopold Center Completed Grant Reports

As Iowa pastures continue to be dominated by cool-season grass species, strategic integration of a single mob-grazing event into pasture management offers a tool to simultaneously increase productivity of pastures and to improve grassland wildlife habitat through increased biodiversity. However, the success of the maneuver depends on climate, soil and landscape.


Genetic Markers Found For Response To Heat Stress In Chickens, Angelica G. Bjorkquist, Max F. Rothschild, Michael E. Persia, Chris Ashwell, Carl Schmidt, Susan J. Lamont Jan 2015

Genetic Markers Found For Response To Heat Stress In Chickens, Angelica G. Bjorkquist, Max F. Rothschild, Michael E. Persia, Chris Ashwell, Carl Schmidt, Susan J. Lamont

Animal Industry Report

A unique line of chickens was evaluated for response to heat stress. We measured body temperature, body weight, breast yield, and digestibility. Genomic (DNA) markers were identified by genotyping on the Affymetric 600K array. We conclude that the traits measured during heat stress do have a genetic component. Genomic markers for the response to heat stress have been identified and may be used for breeding more resilient animals.


Accuracy Of Genomic Prediction For Prrs Antibody Response, Nick V. L. Serão, Bob Kemp, Benny Mote, Philip Willson, John Harding, Steve Bishop, Graham Plastow, Jack C. M. Dekkers Jan 2015

Accuracy Of Genomic Prediction For Prrs Antibody Response, Nick V. L. Serão, Bob Kemp, Benny Mote, Philip Willson, John Harding, Steve Bishop, Graham Plastow, Jack C. M. Dekkers

Animal Industry Report

The accuracy of genomic prediction for antibody response to Porcine Reproductive and Respiratory Syndrome (PRRS), measured as S/P ratio, was evaluated using two independent datasets of Landrace x Large White females. Results demonstrate that antibody response during a PRRS outbreak can be predicted with high accuracy using genetic markers in two regions on chromosome 7. One of these regions includes the Major Histocompatibility Complex. The high accuracy for this region indicates that marker effects are consistent across Landrace x Large White populations.


Sequencing A Shrimp Diversity Panel, Emily Kawaler, Max F. Rothschild, Zhiqiang Du Jan 2015

Sequencing A Shrimp Diversity Panel, Emily Kawaler, Max F. Rothschild, Zhiqiang Du

Animal Industry Report

Eighty-six shrimp (eighty Pacific White, six Tiger shrimp) from ten different geographic regions were sequenced with a twofold goal: first, to better understand and document the genetic makeup of the species, and second, to discover genetic differences between shrimp lines that may facilitate the breeding of shrimp with better performance traits


Development And Use Of A Survey Tool To Determine The Efficacy Of Livestock Truck Washes In Iowa, Amber M. Danielson, Anna K. Johnson, Kenneth J. Stalder, Rodney B. Baker, Troy Bigelow, Daniel S. Andersen Jan 2015

Development And Use Of A Survey Tool To Determine The Efficacy Of Livestock Truck Washes In Iowa, Amber M. Danielson, Anna K. Johnson, Kenneth J. Stalder, Rodney B. Baker, Troy Bigelow, Daniel S. Andersen

Animal Industry Report

The transmission of disease among livestock farms could be addressed by the efficiency of truck washes to clean and disinfect trailers used for transporting animals. Collecting swab samples from trailers and cabs of identified truck wash trailers will help to determine the proper procedures and steps needed to reduce the transmission of disease. Truck washes in the state of Iowa were identified and invited to participate in a questionnaire that will provide helpful information for this research. The main goals of this study are to 1) determine the areas in the truck washing process that pose a high risk to ...


Evaluation Of Teat Coverage Persistency And Teat Health For Three Dry Period Persistent Barrier Teat Sealant Dips, Melanie Matti, Alislinn A. Pomfret, Leo L. Timms Jan 2015

Evaluation Of Teat Coverage Persistency And Teat Health For Three Dry Period Persistent Barrier Teat Sealant Dips, Melanie Matti, Alislinn A. Pomfret, Leo L. Timms

Animal Industry Report

Mastitis research has shown that 40-50% of intramammary infections (IMI) are contracted during the dry or non-lactating period with the greatest percentages of these occurring during the first and last two weeks of the dry period. The ability to develop and apply external persistent barrier teat dip products (like a liquid bandage) that can persist for these 1 week periods could decrease IMI, thus improving animal health and performance, and product quality and safety. The objective of this study was to evaluate and compare 3 persistent barrier dry cow teat sealant dips with particular interest and comparisons of dip persistency ...


Estimation Of Haplotype Diversity And Recombination Rate On Chromosomes 5 And 15 In Layer Chickens, Ziqing Weng, Anna Wolc, Jesus Arango, Petek Settar, Janet E. Fulton, Neil P. O'Sullivan, Rohan L. Fernando, Jack C. M. Dekkers, Dorian J. Garrick Jan 2015

Estimation Of Haplotype Diversity And Recombination Rate On Chromosomes 5 And 15 In Layer Chickens, Ziqing Weng, Anna Wolc, Jesus Arango, Petek Settar, Janet E. Fulton, Neil P. O'Sullivan, Rohan L. Fernando, Jack C. M. Dekkers, Dorian J. Garrick

Animal Industry Report

The objectives of this study were to compare the performance of different haplotype reconstruction approaches, characterize haplotype diversity and identify recombination hotspots on chromosomes 5 and 15 in layer chicken. BEAGLE, DAGPHASE, and fastPHASE software recognized fewer haplotypes than two other methods. In total, 10 and 2 recombination hotspots were identified on chromosomes 5 and 15, respectively. Further study is needed to confirm these regions with high recombination rate and high haplotype diversity.


An Experimental Course: Animal Handling, Safety, And Well-Being, Brady M. Mcneil, Heather A. Jennings, Christen G. Jackson, Anna K. Johnson, Jodi A. Sterle Jan 2015

An Experimental Course: Animal Handling, Safety, And Well-Being, Brady M. Mcneil, Heather A. Jennings, Christen G. Jackson, Anna K. Johnson, Jodi A. Sterle

Animal Industry Report

Students in the Department of Animal Science at Iowa State University are coming from increasingly diverse backgrounds, with little to no experience working with or handling various livestock species. In order to best accommodate these students, additional courses are being developed, one of which is Animal Science 190X: Animal Handling, Safety, and Well-Being. Through the course, students handle all major livestock species; sheep, swine, poultry, horses, beef cattle and dairy cattle, and are required to demonstrate handling knowledge and skills learned as part of a final assessment. This creates an opportunity for students lacking a livestock background to feel more ...


Fatty Acid Snp Interaction Analysis In Angus Sired Beef Cattle, Luke M. Kramer, James E. Koltes, Eric R. Fritz-Waters, Mary Sue Mayes, Alysta Markey, Mahdi Saatchi, Nathan T. Weeks, James M. Reecy Jan 2015

Fatty Acid Snp Interaction Analysis In Angus Sired Beef Cattle, Luke M. Kramer, James E. Koltes, Eric R. Fritz-Waters, Mary Sue Mayes, Alysta Markey, Mahdi Saatchi, Nathan T. Weeks, James M. Reecy

Animal Industry Report

The triacylglyceride (TAG) fatty acid content in meat from Angus-sired cattle was analyzed for non-additive genetic effects. A total of 11,482 significant DNA marker interactions (false discovery rate [FDR] < 0.05) were detected across thirty-seven different TAG fatty acids. Interactions were not evenly distributed amongst all fatty acids analyzed, and types of interactions (additive-by-additive, additive-by-dominance, and dominance-by-dominance) varied within each individual fatty acid. These results indicate that it may be possible to account for additional genetic variance amongst TAG fatty acids over and above individual markers.


Effects Of Blast Chilling On Fresh Pork Quality In Chops From The Longissimus Dorsi, Aaron M. Blakely, Edward M. Steadham, Kenneth J. Prusa, Christine A. Fedler, Elisabeth J. Huff-Lonergan, Steven M. Lonergan Jan 2015

Effects Of Blast Chilling On Fresh Pork Quality In Chops From The Longissimus Dorsi, Aaron M. Blakely, Edward M. Steadham, Kenneth J. Prusa, Christine A. Fedler, Elisabeth J. Huff-Lonergan, Steven M. Lonergan

Animal Industry Report

Carcasses (n=40) with defined fat free lean and carcass weight were selected 45 minutes postmortem. Carcasses were split, and sides subjected to conventional or blast chilling regimens. Sides that were blast chilled had Longissimus dorsi (LD) chops with slower pH decline, greater cook loss and greater Warner-Bratzler Shear force than chops from conventionally chilled sides. These results demonstrate that current blast chilling practices have the potential to negatively impact pork tenderness.


Characterization Of The F94l Double Muscling Mutation In Pure- And Crossbred Limousin Animals, Jungjae Lee, Hailin Su, Rohan L. Fernando, Dorian J. Garrick, Jeremy Taylor Jan 2015

Characterization Of The F94l Double Muscling Mutation In Pure- And Crossbred Limousin Animals, Jungjae Lee, Hailin Su, Rohan L. Fernando, Dorian J. Garrick, Jeremy Taylor

Animal Industry Report

The objective of this study was to investigate the nature of the effect of the F94L variant in the myostatin (MSTN) gene on economic traits in Limousin and Limousin-Angus crossbred animals in the context of genomic analyses using Illumina BovineSNP50 Bead chip genotypes.


Effect Of Estrus Activity When Evaluating Feed Efficiency In Heifers, Garland R. Dahlke, Patrick J. Gunn Jan 2015

Effect Of Estrus Activity When Evaluating Feed Efficiency In Heifers, Garland R. Dahlke, Patrick J. Gunn

Animal Industry Report

Estrus activity in virgin heifers tends to affect the outcome in measurements observed during performance and feed utilization tests. Prior to any testing it is prudent to identify those females that have shown estrus activity consistently and those which have not, then evaluate animals for feed efficiency grouped by stage of sexual maturity.


Effect Of Trace Mineral Injection And Optaflexx On Growth Performance And Carcass Characteristics Of Finishing Cattle, Olivia N. Genther-Schroeder, Christopher A. Clark, Stephanie L. Hansen Jan 2015

Effect Of Trace Mineral Injection And Optaflexx On Growth Performance And Carcass Characteristics Of Finishing Cattle, Olivia N. Genther-Schroeder, Christopher A. Clark, Stephanie L. Hansen

Animal Industry Report

Utilizing a trace mineral (TM) injection approximately 90 d prior to harvest may improve growth performance and carcass characteristics when the β-agonist Optaflexx is not used. This may provide a unique opportunity for TM injection to be used in natural programs, to avoid the use of β-agonists, but still maintain high rates of growth. However, using a TM-injection only 28 d prior to harvest appears to have no additional benefit, and may decrease carcass quality.


Changes In The Protein Profile Of Porcine Liver In Response To Immune System Stimulation, Amanda C. Outhouse, Kyle Grubbs, Christopher K. Tuggle, Jack C. M. Dekkers, Nicholas K. Gabler, Steven M. Lonergan Jan 2015

Changes In The Protein Profile Of Porcine Liver In Response To Immune System Stimulation, Amanda C. Outhouse, Kyle Grubbs, Christopher K. Tuggle, Jack C. M. Dekkers, Nicholas K. Gabler, Steven M. Lonergan

Animal Industry Report

Immune system function has a direct influence on swine growth. Using lipopolysaccharide (LPS) to stimulate the immune system of pigs provides insight on how they handle immunological stress. Several proteins were shown to be part of the liver’s response to LPS. These proteins included heat shock protein (HSP) 60, HSP70, and peroxiredoxin-2. Changes in the abundance of these proteins indicate the extent to which an animal can respond to this immune system stimulation (ISS). Proteins responsible for cellular rescue were found to be increased in abundance in pigs with stimulated immune systems.


Effects Of Label Dose Permethrin Use In Yearling Angus Beef Bulls On Reproductive Function And Testicular Histopathology, Tyler M. Dohlman, Patrick E. Phillips, Darin M. Madson, Christopher A. Clark, Patrick J. Gunn Jan 2015

Effects Of Label Dose Permethrin Use In Yearling Angus Beef Bulls On Reproductive Function And Testicular Histopathology, Tyler M. Dohlman, Patrick E. Phillips, Darin M. Madson, Christopher A. Clark, Patrick J. Gunn

Animal Industry Report

To eliminate the potential for insect borne diseases and improve productivity in cow-calf operations, many producers use pour-on pyrethroids. However, popular press literature has identified potential links between use of pyrethroids and reproductive function failures in bulls. While literature in mice and rats have reported potential endocrine disruption of sex steroids resulting from pyrethroid exposure, effects of pyrethroid use on bull fertility is still questionable. The objective of this study was to measure reproductive parameters in peripubertal Angus bulls using a commonly used pyrethroid pour-on. We hypothesized that use of a pyrethroid pour-on at labeled dose would have limited effects ...


Evaluation Of Teat Coverage Persistency And Teat Health For Four Dry Period Persistent Barrier Teat Sealant Dips, Melanie Matti, Leo L. Timms Jan 2015

Evaluation Of Teat Coverage Persistency And Teat Health For Four Dry Period Persistent Barrier Teat Sealant Dips, Melanie Matti, Leo L. Timms

Animal Industry Report

Mastitis research has shown that 40-50% of intramammary infections (IMI) are contracted during the dry or non-lactating period with the greatest percentages of these occurring during the first and last two weeks of the dry period. The ability to develop and apply external persistent barrier teat dip products (like a liquid bandage) that can persist for these 1 week periods could decrease IMI, thus improving animal health and performance, and product quality and safety. The objective of this study was to evaluate and compare 4 persistent barrier dry cow teat sealant dips with particular interest and comparisons of dip persistency ...


Effects Of Increasing Supplementation Of Rumen Undegradable Protein On Plasma Essential Amino Acid Concentrations In Beef Cows Consuming Low Quality Forage, Taylor C. Geppert, Allison Meyer, Patrick J. Gunn Jan 2015

Effects Of Increasing Supplementation Of Rumen Undegradable Protein On Plasma Essential Amino Acid Concentrations In Beef Cows Consuming Low Quality Forage, Taylor C. Geppert, Allison Meyer, Patrick J. Gunn

Animal Industry Report

The effects of pairing a low quality forage with increasing metabolizable protein (MP) supplementation from a moderately abundant rumen undegradable protein (RUP) source (corn gluten meal; 62% RUP) on essential plasma amino acid (AA) concentrations were evaluated in a 60-day trial. Non-pregnant, non-lactating cows (n=24) were offered ad libitum access to cornstalks and fed 1 of 3 isocaloric diets (0.48 NEm/lb) and supplemented primarily with corn gluten meal to provide 100% MP requirements (CON), 125% MP requirements (MP125), or 150% MP requirements (MP150). It was observed that increasing concentrations of MP in the diet from a moderately ...


Opportunities And Challenges In A Changing Beef Industry: Results Of A Statewide Needs Assessment In Iowa, Patrick J. Gunn, Daniel D. Loy Jan 2015

Opportunities And Challenges In A Changing Beef Industry: Results Of A Statewide Needs Assessment In Iowa, Patrick J. Gunn, Daniel D. Loy

Animal Industry Report

The U.S. beef industry is poised for growth following increased contraction over the past decade that has resulted in the lowest cattle inventory in over 60 years. However, sustainable, long term growth of the industry is dependent upon early identification of issues that may inhibit profitability. A series of seven listening sessions conducted across Iowa in November and December of 2013 by the Iowa Beef Center identified land access, farm transition, production efficiency, marketing, genetics, data management, feedstuffs, and animal health as “mega-issues” facing producers. Specific issues under each of these overarching categories will guide future extension programming efforts ...


Influence Of Feed Efficiency Ranking On Diet Digestibility And Performance Of Beef Steers, Jason R. Russell, Stephanie L. Hansen Jan 2015

Influence Of Feed Efficiency Ranking On Diet Digestibility And Performance Of Beef Steers, Jason R. Russell, Stephanie L. Hansen

Animal Industry Report

The current study evaluated diet digestibility and finishing phase growth performance in steers previously evaluated for feed efficiency during the growing phase. Based on growing phase feed efficiency, steers were classified as highly or lowly feed efficient. During the finishing phase, the highly feed efficient steers remained more feed efficient. Steers were fed either corn or roughage-based diets during the growing phase and then transitioned to either corn or byproduct-based diets during the finishing phase. Dry matter digestibility was strongly positively correlated in steers grown/finished on corn or grown/finished on high fiber diets (roughage, byproduct). Conversely, there was ...


Accuracy Of Genomic Predictions For Birth, Weaning And Yearling Weights In Us Simmental Beef Cattle, Hailin Su, Rohan L. Fernando, Dorian J. Garrick, Bruce Golden Jan 2015

Accuracy Of Genomic Predictions For Birth, Weaning And Yearling Weights In Us Simmental Beef Cattle, Hailin Su, Rohan L. Fernando, Dorian J. Garrick, Bruce Golden

Animal Industry Report

Direct genomic breeding values (DGV) based on actual or imputed GeneSeek Genomic Profiler HD (GGPHD) genotypes were obtained for birth, weaning and yearling weights using Bayesian regression on about 20,000 US Simmental pure- or cross-bred beef cattle. Accuracies of DGV were quantified using 4-fold cross validation. Accuracies expressed as genetic correlations between DGV and trait ranged from 0.61 to 0.65, and the regressions of phenotype on DGV ranged from 0.61 to 0.66. These results indicate good predictive ability of genomic prediction with GGPHD chips but DGV need to be adjusted for bias.


Optimal Dietary Energy And Protein For Gilt Development: Age At Puberty, Ovulation Rate, And Reproductive Tract Traits, Julia A. Calderón Díaz, Jeffrey L. Vallet, Clay Lents, Danny Nonneman, Jeremy Miles, Elaine Wright, Lea Rempel, Robert Cushman, Bradley Freking, Gary Rohrer, Christina Phillips, Ashley Dedecker, George Foxcroft, Kenneth J. Stalder Jan 2015

Optimal Dietary Energy And Protein For Gilt Development: Age At Puberty, Ovulation Rate, And Reproductive Tract Traits, Julia A. Calderón Díaz, Jeffrey L. Vallet, Clay Lents, Danny Nonneman, Jeremy Miles, Elaine Wright, Lea Rempel, Robert Cushman, Bradley Freking, Gary Rohrer, Christina Phillips, Ashley Dedecker, George Foxcroft, Kenneth J. Stalder

Animal Industry Report

The effect of feeding different lysine and metabolizable energy (ME) levels to 1221 crossbred Large White × Landrace developing gilts housed in groups from 100 d of age until slaughter (approximately 260 d of age) on age at puberty and reproductive tract measurements were evaluated. Gilts were randomly allotted to six corn-soybean diets formulated to provide two standardized ileal digestible lysine levels [100% (high, HL) and 85% (low, LL)] and threemetabolizable energy levels [ME, 90% (low, LME), 100% (medium, MME), 110% (high, HME). Average age at puberty was 193 d of age. There were no effects of the dietary treatments on ...


Improved Accuracy Of Genomic Prediction For Traits With Rare Qtl By Fitting Haplotypes, Xiaochen Sun, Rohan L. Fernando, Dorian J. Garrick, Jack C. M. Dekkers Jan 2015

Improved Accuracy Of Genomic Prediction For Traits With Rare Qtl By Fitting Haplotypes, Xiaochen Sun, Rohan L. Fernando, Dorian J. Garrick, Jack C. M. Dekkers

Animal Industry Report

Genomic prediction estimates breeding values by exploiting linkage disequilibrium (LD) between quantitative trait loci (QTL) and single nucleotide polymorphisms (SNPs). High LD cannot occur when QTL and SNPs have different minor allele frequencies (MAF). Marker panels tend to use SNPs with high MAF and will have limited ability to predict rare QTL alleles. In practice, increasing SNP density has not improved prediction accuracy. A possible reason is that many traits are characterized by rare QTL. In that case, linear models fitting haplotypes could have advantage because haplotypes can be in complete LD with QTL alleles. SNP genotypes were simulated to ...


Effect Of Wur Genotype And Prrs Vaccination On Pigs Co-Infected With Prrs And Pcv2b, Jenelle R. Dunkelberger, Nick V. L. Serão, Maureen Kerrigan, Joan Lunney, Bob Rowland, Jack C. M. Dekkers Jan 2015

Effect Of Wur Genotype And Prrs Vaccination On Pigs Co-Infected With Prrs And Pcv2b, Jenelle R. Dunkelberger, Nick V. L. Serão, Maureen Kerrigan, Joan Lunney, Bob Rowland, Jack C. M. Dekkers

Animal Industry Report

Average daily gain (ADG) and viral load (VL) were evaluated for pigs co-infected with porcine reproductive and respiratory syndrome (PRRS) virus (PRRSV) and porcine circovirus type 2b (PCV2b). Pigs were pre-selected for WUR genotype (a marker on chromosome 4 associated with weight gain and VL under PRRSV-challenge), half were vaccinated for PRRS, and half were not. Results indicate that vaccination for PRRS resulted in slower growth prior to co-infection and that the AB WUR genotype was associated with faster growth prior to co-infection, lower PRRS VL, and lower PCV2b VL in vaccinated pigs.