Genetics and Genomics Commons^™

Postnatal Nutrient Repartitioning Due To Adaptive Developmental Programming, Robert J. Posont, Dustin T. Yates

Department of Animal Science: Faculty Publications

The consequences of prenatal stress on lifelong metabolic function and health was first proposed by David Barker and Nicholas Hales with the publication of their Thrifty Phenotype Hypothesis in the early 1990s.1,2 Subsequent studies in humans and animals have further demonstrated that stress-induced adaptive fetal programming leads to tissue-specific changes in metabolic function and growth capacity.3,4 Developmental adaptations to the intrauterine nutrient restriction that accompanies most maternofetal stressors target regulatory pathways for nutrient utilization in non-essential tissues such as skeletal muscle.4-6 This aids intrauterine survival by re-appropriating nutrients to support neural, cardiac, and endocrine tissue function but reduces metabolic efficiency …

Utilizing An Electronic Feeder To Measure Mineral And Energy Supplement Intake In Beef Heifers Grazing Native Range, Kacie L. Mccarthy, Sarah R. Underdahl, Michael Undi, Stephanie Becker, Carl R. Dahlen

Department of Animal Science: Faculty Publications

Introduction

Grasslands in the Northern Plains provide the primary forage source for ruminants throughout much of the year (Schauer et al., 2004). Supplementation practices are often necessary to maintain production and offset forage nutritive decline throughout the grazing season (Schauer et al., 2004; Cline et al., 2009). Typically, to maintain a targeted production level, energy and protein supplementations are used for grazing livestock (Caton and Dhuyvetter, 1997). For developing heifers consuming low-quality forages, inclusion of energy ingredients into supplements may be beneficial for growth and reproductive performance (Schillo et al., 1992; Ciccioli et al., 2005; Cappellozza et al., 2014). In …

Beef Production Systems In The Nebraska Sandhills, Mckay Reed Erickson

Department of Animal Science: Dissertations, Theses, and Student Research

Four studies were conducted to determine the effectiveness of improving production systems of beef cattle in the Sandhills region of Nebraska. These studies were to determine impacts of modified estrus synchronization protocols, genomic testing heifer calves for longevity, and evaluation of 2 differing calving systems (March or May) for improving biological outcome and improved production. Experiment 1 utilized 180 yearling heifers to determine the effectiveness of a second dose of prostaglandin F_2α(PGF) with those females not expressing estrus after an initial 14 d MGA-PG estrus synchronization protocol. The treatment of PGF did increase estrus expression, but did not …

Effect Of Cooled Perches On The Efficacy Of An Induced Molt In White Leghorn Laying Hens Previously Exposed To Heat Stress, J Y. Hu, P Y. Hester, Y Xiong, R S. Gates, M M. Makagon, H W. Cheng

Department of Animal Science: Faculty Publications

This study examined the effect of water chilled perches on hen production and physiological responses to induced molt during elevated temperatures. A total of 288White Leghorns at 82 wk of age were housed in 36 cages of 6 banks. Each bank was assigned to 1 of 3 treatments: cooled perches, air perches, and no perches. The hens were subjected to 2 heat episodes during their first laying cycle at week 21 to 35 and week 73 to 80, respectively. The hens were subjected to a 28 D nonfasted molting regimen starting at 85 wk of age. Cyclic heat of 32◦C …

Hiding In The Lianas Of The Tree Of Life: Molecular Phylogenetics And Species Delimitation Reveal Considerable Cryptic Diversity Of New World Vine Snakes, Robert C. Jadin, Christopher Blair, Michael J. Jowers, Anthony Carmona, John C. Murphy

Publications and Research

The Brown Vine Snake, Oxybelis aeneus, is considered a single species despite the fact its distribution covers an estimated 10% of the Earth’s land surface, inhabiting a variety of ecosystems throughout North, Central, and South America and is distributed across numerous biogeographic barriers. Here we assemble a multilocus molecular dataset (i.e. cyt b, ND4, cmos, PRLR) derived from Middle American populations to examine for the first time the evolutionary history of Oxybelis and test for evidence of cryptic lineages using Bayesian and maximum likelihood criteria. Our divergence time estimates suggest that Oxybelis diverged from its sister genus, Leptophis …

X-Inactivation And Epigenetics, Serena Weston

Thinking Matters Symposium Archive

To prevent abnormal development caused by expressing both X chromosomes, female mammals inactivate one of their X chromosomes using an epigenetic process called dosage compensation. This literature review examines how X chromosome inactivation (XCI) occurs during the formation and development of an embryo. This condensation of DNA is marked by histone tail modifications, DNA methylation, and the arrival of structural proteins resulting in extraordinarily stable heterochromatin. X-inactivation is regulated in cis by the X-inactivation center (Xic) that contains the Xist gene and its antisense gene, Tsix. On one X chromosome, Xist RNA is expressed and coats the center of the …

Male Determining Gene Nix May Bring An End To Transmission Of Diseases Through Mosquitoes, Mohammed Mahdi

Thinking Matters Symposium Archive

Female mosquitoes take blood from humans to gain protein needed to produce eggs, and in the process they can transmit viruses, such as Zika, Dengue, and chikungunya, or parasites, such as malaria. Male mosquitoes do not transmit diseases. This literature review will examine what is known about how sex is determined in mosquitoes and how this can be used to manipulate the females that spread diseases to humans. Using CRISPR Cas9, the lab of Zhijian Tu removed the Nix gene from mosquito embryos; all of these were feminized. Ectopic overexpression of Nix gene product in mosquito embryos caused even genetically …

Crispr-Mediated Gene Editing: Scientific And Ethical Issues, Jarrod Bailey

Genetics Collection

There remains substantial evidence to warrant great concern over the poor efficiency and specificity of clustered regularly interspaced short palindromic repeats (CRISPR)-mediated genetic modification (GM), despite relatively minor improvements compared to other GM methods. These issues cause persistent, adverse, ethical, and scientific consequences for GM animals, which may never be sufficiently resolvable.

Substantial Red Wolf Genetic Ancestry Persists In Wild Canids Of Southwestern Louisiana, Jennifer R. Adams, John J. Cox, Lisette P. Waits

Forestry and Natural Resources Faculty Publications

Concerns over red wolf (Canis rufus) extinction caused by hybridization with coyotes (C. latrans) led to the capture and removal of remnant wild wolves from southwestern Louisiana and southeastern Texas, United States, during the 1970s. Here we show that despite decades of unmitigated hybridization, and declaration of endangered red wolves as functionally extinct in the wild, red wolf mitochondrial or nuclear DNA ancestry persists in ∼55% of contemporary wild canids sampled in southwestern Louisiana. Surprisingly, one individual had 78–100% red wolf ancestry, which is within the range for 75% red wolf, red wolf backcross, or putative …

Maternal Inflammation At Midgestation Impairs Subsequent Fetal Myoblast Function And Skeletal Muscle Growth In Rats, Resulting In Intrauterine Growth Restriction At Term, Caitlin N. Cadaret, Robert J. Posont, Kristin A. Beede, Hannah E. Riley, John Dustin Loy, Dustin T. Yates

Department of Animal Science: Faculty Publications

Maternal inflammation induces intrauterine growth restriction (MI-IUGR) of the fetus, which compromises metabolic health in human offspring and reduces value in livestock. The objective of this study was to determine the effect of maternal inflammation at midgestation on fetal skeletal muscle growth and myoblast profiles at term. Pregnant Sprague-Dawley rats were injected daily with bacterial endotoxin (MI-IUGR) or saline (controls) from the 9th to the 11th day of gestational age (dGA; term = 21 dGA). At necropsy on dGA 20, average fetal mass and upper hindlimb cross-sectional areas were reduced (P < 0.05) in MI-IUGR fetuses compared with controls. MyoD+ and myf5+ myoblasts were less abundant (P < 0.05), and myogenin+ myoblasts were more abundant (P < 0.05) in MI-IUGR hindlimb skeletal muscle compared with controls, indicating precocious myoblast differentiation. Type I and Type II hindlimb muscle fibers were smaller (P < 0.05) in MI-IUGR fetuses than in controls, but fiber type proportions did not differ between experimental groups. Fetal blood plasma TNFα concentrations were below detectable amounts in both experimental groups, but skeletal muscle gene expression for the cytokine receptors TNFR1, IL6R, and FN14 was greater (P < 0.05) in MI-IUGR fetuses than controls, perhaps indicating enhanced sensitivity to these cytokines. Maternal blood glucose concentrations at term did not differ between experimental groups, but MI-IUGR fetal blood contained less (P < 0.05) glucose, cholesterol, and triglycerides. Fetal-to-maternal blood glucose ratios were also reduced (P < 0.05), which is indicative of placental insufficiency. Indicators of protein catabolism, including blood plasma urea nitrogen and creatine kinase, were greater (P < 0.05) in MI-IUGR fetuses than in controls. From these findings, we conclude that maternal inflammation at midgestation causes muscle-centric fetal programming that impairs myoblast function, increases protein catabolism, and reduces skeletal muscle growth near term. Fetal muscle sensitivity to inflammatory cytokines appeared to be enhanced after maternal inflammation, which may represent a mechanistic target for improving these outcomes in MI-IUGR fetuses.

Blood Parasites Infecting The Hoatzin (Opisthocomus Hoazin), A Unique Neotropical Folivorous Bird, M. Andreína Pacheco, M. Alexandra García-Amado, Jaime Manzano, Nubia E. Matta, Ananias A. Escalante

Harold W. Manter Laboratory of Parasitology: Library Materials

The Hoatzin (Opisthocomus hoazin) is the only extant member of the order Opisthocomiformes. This unique South American bird lives in the riparian lowland vegetation characteristic of the Amazon and Orinoco basins. Hoatzins nest in communal social units close to water bodies; they are strictly folivores being the only bird with pregastric fermentation in the crop. Because of the complex logistics involved in capturing this bird, there is a knowledge gap on its parasites. This study documents two distant lineages of haemosporidian parasites (Plasmodium spp.) in a juvenile and two adults sampled in the Cojedes state, Venezuela. Although …

Effect Of Cooled Perches On Performance, Plumage Condition, And Foot Health Of Caged White Leghorn Hens Exposed To Cyclic Heat, J Y. Hu, P Y. Hester, M M. Makagon, Y Xiong, R S. Gates, H W. Cheng

Department of Animal Science: Faculty Publications

We examined the effects of water-chilled perches as cooling devices on hen performance during 2 summers using daily cyclic heat. White Leghorns, 17 wk of age, were assigned to 36 cages arranged into 6 banks. The banks were assigned to cooled perches, air perches, and no perches resulting in 2 replicate banks and 12 cages per treatment. Chilled water (10^◦C) was circulated through the cooled perches during heat episodes. Daily cyclic heat of 35^◦C was applied from 0600 to1800 h with a lowering of temperature to 28^◦C from 1800 to 0600 h during the …

Biotechnological Application In Aquaculture And Its Sustainability Constraints, Olaganathan Rajee, Tang Kar Mun Alicia

Publications

The valuable nutritional and biochemical properties have made fisheries products one of the most vital high-quality protein sources for human consumption. Aquaculture has become the great alternative to substitute wild catches when the yield from fishing are no longer sufficient to sustain the massive food demand of the human population which is constantly burgeoning. However, aquaculture requires multidisciplinary approaches with holistic and environmental-friendly management measures to ensure its long term success and sustainability. Biotechnological applications have enhanced the effectiveness and cost-efficiencies of aquaculture by augmenting the productivity of aquaculture to meet global needs. Despite the benefits, the biotechnological application in …

Increasing The Concentration Of Linolenic Acid In Diets Fed To Jersey Cows In Late Lactation Does Not Affect Methane Production, J. V. Judy, G. C. Bachman, T. M. Brown-Brandl, S. C. Fernando, K. E. Hales, K. J. Harvatine, P. S. Miller, P. J. Kononoff

Department of Animal Science: Faculty Publications

Although the inclusion of fat has reduced methane production in ruminants, relatively little research has been conducted comparing the effects of source and profile of fatty acids on methane production in lactating dairy cows. A study using 8 multiparous (325 ± 17 DIM; mean ± SD) lactating Jersey cows was conducted to determine effects of feeding canola meal and lard versus extruded byproduct containing flaxseed as a high-C18:3 fat source on methane production and diet digestibility in late-lactation dairy cows. A crossover design with 32-d periods (28-d adaptation and 4-d collections) was used to compare 2 different fat sources. Diets …

Metabolomics Profile And Targeted Lipidomics In Multiple Tissues Associated With Feed Efficiency In Beef Steers, Virginia M. Artegoitia, Andrew P. Foote, Ronald M. Lewis, Harvey C. Freetly

Department of Animal Science: Faculty Publications

A study of multiple tissues was conducted to identify potential metabolic differences in cattle differing in feed efficiency. Individual feed intake and body weight was measured on 144 steers during 105 days on a high-concentrate ration. Steers were selected according to differences in average daily gain (ADG) with those with the greatest ADG (n = 8; 1.96 ± 0.02 kg/day) and least ADG (n = 8; 1.57 ± 0.02 kg/day), whose dry matter intake was within 0.32 SD of the mean intake (10.10 ± 0.05 kg/day). Duodenum, liver, adipose, and longissimus-dorsi were collected at slaughter, and metabolomics profiles …

Maternal Inflammation At 0.7 Gestation In Ewes Leads To Intrauterine Growth Restriction And Impaired Glucose Metabolism In Offspring At 30 D Of Age, Robert J. Posont, Caitlin N. Cadaret, Kristin A. Beede, Joslyn K. Beard, Rebecca M. Swanson, Rachel L. Gibbs, Jessica L. Petersen, Dustin T. Yates

Department of Animal Science: Faculty Publications

Fetal programming associated with intrauterine growth restriction (IUGR) leads to lifelong deficits in growth and metabolic function (Hales and Barker, 2013). IUGR arises when fetuses respond to poor in utero conditions by developing adaptations that repartition nutrients to critical tissues and away from skeletal muscle (Yates et al., 2012, 2018). This fetal programming is beneficial in utero but leads to persistent reductions in muscle mass and glucose homeostasis in offspring (DeFronzo et al., 1981). Recent studies by our laboratory in sheep and rats demonstrate that maternal inflammation during gestation induces fetal inflammatory adaptations that impair growth and disrupt muscle glucose …

Comparison Of Different Functions To Describe Growth From Weaning To Maturity In Crossbred Beef Cattle, Madeline J. Zimmermann, Larry A. Kuehn, Matthew L. Spangler, R. Mark Thallman, Warren M. Snelling, Ronald M. Lewis

Department of Animal Science: Faculty Publications

Cow mature weight (MWT) has increased in the past 30 yr. Larger cows cost more to maintain, but their efficiency—and thus profitability— depends on the production environment. Incorporating MWT effectively into selection and mating decisions requires understanding of growth to maturity. The objective of this study was to describe growth to maturity in crossbred beef cattle using Brody, spline, and quadratic functions. Parameter estimates utilized data on crossbred cows from cycle VII and continuous sampling phases of the Germplasm Evaluation Program at the U.S. Meat Animal Research Center. The MWT were estimated at 6 yr from the fitted parameters obtained …

Forms Of Supplemental Selenium In Vitamin-Mineral Mixes Differentially Affect Serological And Hepatic Parameters Of Growing Beef Steers Grazing Endophyte-Infected Tall Fescue, Yang Jia

Theses and Dissertations--Animal and Food Sciences

Consumption of endophyte-infected tall fescue results in a syndrome of negatively altered physiological systems, collectively known as fescue toxicosis. Another challenge to endophyte-infected tall fescue -based beef cattle operations is that the soils often are selenium (Se) poor, necessitating the need to provide supplemental Se. To test the general hypothesis that different forms of supplemental Se would ameliorate the negative effects of fescue toxicosis, predominately-Angus steers (BW = 183 ± 34 kg) were randomly selected from herds of fall-calving cows grazing an endophyte-infected tall fescue pasture and consuming vitamin-mineral mixes that contained 35 ppm Se as sodium selenite (ISe), SELPLEX …

Evaluation Of Genotype Quality Parameters For Sowpro90, A New Genotyping Array For Swine, Hiruni R. Wijesena, Gary A. Rohrer, Dan J. Nonneman, Brittney N. Keel, Jessica L. Petersen, Stephen D. Kachman, Daniel C. Ciobanu

Department of Animal Science: Faculty Publications

Understanding early predictors of sow fertility has the potential to improve genomic predictions. A custom SNP array (SowPro90 produced by Affymetrix) was developed to include genetic variants overlapping quantitative trait loci for age at puberty, one of the earliest indicators of sow fertility, as well as variants related to innate and adaptive immunity. The polymorphisms included in the custom genotyping array were identified using multiple genomic approaches including deep genomic and transcriptomic sequencing and genome-wide associations. Animals from research and commercial populations (n = 2,586) were genotyped for 103,476 SNPs included in SowPro90. To assess the quality …

Coding Sequences Of Sarcoplasmic Reticulum Calcium Atpase Regulatory Peptides And Expression Of Calcium Regulatory Genes In Recurrent Exertional Rhabdomyolysis, Stephanie J. Valberg, Kaitlin Soave, Zoe J. Williams, Sudeep Perumbakkam, Melissa Schott, Carrie J. Finno, Jessica L. Petersen, Clara Fenger, Joseph M. Autry, David D. Thomas

Department of Animal Science: Faculty Publications

Background: Sarcolipin (SLN), myoregulin (MRLN), and dwarf open reading frame (DWORF) are transmembrane regulators of the sarcoplasmic reticulum calcium transporting ATPase (SERCA) that we hypothesized played a role in recurrent exertional rhabdomyolysis (RER).

Objectives: Compare coding sequences of SLN, MRLN, DWORF across species and between RER and control horses. Compare expression of muscle Ca²⁺ regulatory genes between RER and control horses.

Animals: Twenty Thoroughbreds (TB), 5 Standardbreds (STD), 6 Quarter Horses (QH) with RER and 39 breed-matched controls.

Methods: Sanger sequencing of SERCA regulatory genes with comparison of amino acid (AA) …

Yes-Associated Protein 1 Is Required For Proliferation And Function Of Bovine Granulosa Cells In Vitro, Michele R. Plewes, Xiaoying Hou, Pan Zhang, Aixin Liang, Guohua Hua, Jennifer R. Wood, Andrea S. Cupp, Xiangmin Lv, Cheng Wang, John S. Davis

Department of Animal Science: Faculty Publications

Yes-associated protein 1 (YAP1) is a major component of the Hippo signaling pathway. Although the exact extracellular signals that control the Hippo pathway are currently unknown, increasing evidence supports a critical role for the Hippo pathway in embryonic development, regulation of organ size, and carcinogenesis. Granulosa cells (GCs) within the ovarian follicle proliferate and produce steroids and growth factors, which facilitate the growth of follicle and maturation of the oocyte.We hypothesize that YAP1 plays a role in proliferation and estrogen secretion of GCs. In the current study, we examined the expression of the Hippo signaling pathway in bovine ovaries and …

Postnatal Β2 Adrenergic Treatment Improves Insulin Sensitivity In Lambs With Iugr But Not Persistent Defects In Pancreatic Islets Or Skeletal Muscle, Dustin T. Yates, Leticia E. Camacho, Amy C. Kelly, Leah V. Steyn, Melissa A. Davis, Andrew T. Antolic, Miranda J. Anderson, Ravi Goyal, Ronald E. Allen, Klearchos K. Papas, William W. Hay Jr, Sean W. Limesand

Department of Animal Science: Faculty Publications

Placental insufficiency causes intrauterine growth restriction (IUGR) and disturbances in glucose homeostasis with associated β adrenergic receptor (ADRβ) desensitization. Our objectives were to measure insulin-sensitive glucose metabolism in neonatal lambs with IUGR and to determine whether daily treatment with ADRβ2 agonist and ADRβ1/β3 antagonists for 1 month normalizes their glucose metabolism. Growth, glucose-stimulated insulin secretion (GSIS) and glucose utilization rates (GURs) were measured in control lambs, IUGR lambs and IUGR lambs treated with adrenergic receptor modifiers: clenbuterol atenolol and SR59230A (IUGR-AR). In IUGR lambs, islet insulin content and GSIS were less than …

Ractopamine Hcl Improved Cardiac Hypertrophy But Not Poor Growth, Metabolic Inefficiency, Or Greater White Blood Cells Associated With Heat Stress In Concentrate-Fed Lambs, Rebecca M. Swanson, Kristin A. Beede, Micayla D. Freeman, Morgan L. Eggleston, Ty B. Schmidt, Jessica L. Petersen, Dustin T. Yates

Department of Animal Science: Faculty Publications

Heat stress decreases livestock performance and well-being (Hahn, 1999; Nienaber and Hahn, 2007), causes metabolic dysfunction that decreases growth efficiency (O’Brien et al., 2010), and alters cardiovascular function (Crandall et al., 2008). Each year, heat stress costs the livestock industry up to $2.5 billion (St-Pierre et al., 2003). Ractopamine HCl acts as a nutrient repartitioning agent (Beermann, 2002); classified as a β adrenergic agonist (βAA), it shares pharmacological properties with adrenaline (Beermann, 2002). βAA increase muscle mass and decreases fat deposition through unknown mechanisms (Beermann, 2002). In feedlot cattle, they increase growth efficiency and improve carcass yield and merit (Scramlin …

Body Composition Estimated By Bioelectrical Impedance Analyses Is Diminished By Prenatal Stress In Neonatal Lambs And By Heat Stress In Feedlot Wethers, Rachel L. Gibbs, Caitlin N. Cadaret, Rebecca M. Swanson, Kristin A. Beede, Robert J. Posont, Ty B. Schmidt, Jessica Lynn Petersen, Dustin T. Yates

Department of Animal Science: Faculty Publications

Body composition correlates to carcass value in livestock, which makes the ability to accurately estimate body composition in the live animal beneficial (Berg and Marchello, 1994). Bioelectrical impedance analysis (BIA) is a clinical tool used to assess body composition in humans (Lukaski et al., 1985), but its use in livestock has been minimal. Lean and fat content contribute to profitability for livestock producers, and poor body composition can be caused by stress that occurs either during in utero development (De Blasio et al., 2007) or during postnatal growth (Boyd et al., 2015). Maternal hyperthermia-induced placental insufficiency (Brown et al., 2015) …

Farm Animals Are Important Biomedical Models, Debora L. Hamernik

Department of Animal Science: Faculty Publications

This issue of Animal Frontiers, “Farm animals are im- portant biomedical models,” describes several examples in which cattle, sheep, pigs, or chickens provide an excellent physiological model for studies related to human health or disease (Figure 1). While previous reports have discussed the use of domestic animals as dual-purpose models that benefit agricultural and biomedical research (Ireland et al., 2008), this issue of Animal Frontiers provides additional and novel examples of the value of farm animals for biomedical re- search. Because farm animals are larger in size than labora- tory species, scientists are able to collect larger volumes and …

The Heritability Of Pampiniform Plexus Vessel Size And Varicocoele In Boars, Tasha R. Gruhot, Lea A. Rempel, Matthew L. Spangler, Stephen D. Kachman, Benny E. Mote

Department of Animal Science: Faculty Publications

Ultrasonography was used to capture a coronal–sagittal image of the veins of the pampiniform plexus (PP) and the testicular artery of 327 maternal‐line boars at approximately 6 months of age at the University of Nebraska—Lincoln. Varicocoele was diagnosed by two methods. Method 1 diagnosed varicocoele when the average vessel area on one side of the scrotum was 1.5 times larger than the average vessel area on the other side of the scrotum. Method 2 diagnosed varicocoele when the average vessel area on one side of the scrotum of a boar was 1.5 times larger than the average vessel on the …

Adaptation Strategies: Ruminants, John B. Gaughan, Veerasamy Sejian, Terry L. Mader, Frank R. Dunshea

Department of Animal Science: Faculty Publications

• Growing populations and reduced access to arable land mean that animal production systems will either need to intensify and/or produce more from a reducing land and other resource base.

• Variable and unpredictable environmental conditions mean that animal production faces numerous challenges. In add- ition to climate, these challenges include increased disease risk, increased nutritional deficiencies, and lack of capital to support diversification.

• Predicted changes in climate will impose selection pressures on traits important for biological fitness (and production).

• Genetic adaptation is important for the future of livestock systems. Animal adaptation involves trade-offs, which must be considered when selecting animals for …

  ---

  Go to article

Livestock Animals To Study Infertility In Women, Mohamed A. Abedal-Majed, Andrea S. Cupp

Department of Animal Science: Faculty Publications

• Anovulation is a major cause of infertility in mammalian females.

• Ovarian research in humans is challenging due to the shortage of “normal tissue” that can be obtained from women that are trying to get pregnant.

• Livestock animals provide valuable resources to investigate the optimal intra-follicular environment required to facilitate folliculogenesis and translate to humans.

• Different livestock models may be more useful depending on the specific biological process studied.

Effect Of Environmental Temperature And Β-Adrenergic Agonist Supplementation On Rumen Volatile Fatty Acid Production In Sheep, Erin M. Duffy, Hannah C. Hamilton, Ty B. Schmidt, Dustin T. Yates, Jessica Lynn Petersen

Department of Animal Science: Faculty Publications

Many environmental and dietary factors affect ruminant livestock performance (Ames, 1980; Carberry et al., 2012). Energy used by ruminants is mainly derived from volatile fatty acids (VFA), including acetate, propionate, and butyrate, which are produced by bacterial fermentation of carbohydrates (Barcroft et al., 1944). With the importance of VFA production in ruminants (Bergman, 1990), it is essential to understand how various conditions livestock may be subjected to, such as ambient conditions and diet, can affect VFA production.

With the profound role of VFA production in energy status of the ruminant, and given that heat stress (HS) events can affect ruminal …

Longitudinal Study Of Humoral Immunity To Bovine Coronavirus, Virus Shedding, And Treatment For Bovine Respiratory Disease In Pre-Weaned Beef Calves, Aspen M. Workman, Larry A. Kuehn, Tara G. Mcdaneld, Michael L. Clawson, John Dustin Loy

Department of Animal Science: Faculty Publications

Background: Bovine coronavirus (BCV) is associated with respiratory infections in cattle of all ages; however, a temporal study to evaluate the effect of BCV immunity on virus shedding and bovine respiratory disease (BRD) incidence in pre-weaned beef calves has not been reported. Thus, we report here a prospective study in three herds of crossbred beef calves (n = 817) with endemic BCV. Serial blood samples for measurement of serum anti-BCV antibody titers and nasal swabs for detection of BCV and other common viral and bacterial BRD pathogens were collected from all calves or subsets of calves at predetermined times …