The Ruminant Telomere-to-Telomere (RT2T) Consortium.

Telomere-to-telomere (T2T) assemblies reveal new insights into the structure and function of the previously 'invisible' parts of the genome and allow comparative analyses of complete genomes across entire clades. We present here an open collaborative effort, termed the 'Ruminant T2T Consortium' (RT2T), that aims to generate complete diploid assemblies for numerous species of the Artiodactyla suborder Ruminantia to examine chromosomal evolution in the context of natural selection and domestication of species used as livestock.

Genome-wide associations with longevity and reproductive traits in U.S. rangeland ewes.

Improving ewe longevity is an important breeding and management goal, as death loss and early culling of mature ewes are economic burdens in the sheep industry. Ewe longevity can be improved by selecting for positive reproductive outcomes. However, the breeding approaches for accomplishing this come with the challenge of recording a lifetime trait.

Ecology and Chronic Wasting Disease Epidemiology Shape Prion Protein Gene Variation in Rocky Mountain Elk (Cervus elaphus nelsoni).

As chronic wasting disease (CWD) continues to spread across North America, the relationship between CWD and host genetics has become of interest. In Rocky Mountain elk (Cervus elaphus nelsoni), one or two copies of a leucine allele at codon 132 of the prion protein gene (132L*) has been shown to prolong the incubation period of CWD. Our study examined the relationship between CWD epidemiology and codon 132 evolution in elk from Wyoming, USA, from 2011 to 2018.

Combined purebred and crossbred genetic evaluation of Columbia, Suffolk, and crossbred lamb birth and weaning weights: systematic effects and heterogeneous variances.

Despite the benefits of crossbreeding on animal performance, genetic evaluation of sheep in the U.S. does not directly incorporate records from crossbred lambs.

Thrombospondin-Related Anonymous Protein (TRAP) Family Expression by Life Stages within the Mammalian Host and Tick Vector.

The tick-transmitted disease bovine babesiosis causes significant economic losses in many countries around the world. Current control methods include modified live-attenuated vaccines that have limited efficacy. Recombinant proteins could provide effective, safe, and low-cost alternative vaccines.

Model definition for genetic evaluation of purebred and crossbred lambs including heterosis.

Crossbreeding is a common practice among commercial sheep producers to improve animal performance. However, genetic evaluation of U.S.

Immunization against a Conserved Surface Polysaccharide Stimulates Bovine Antibodies with Opsonic Killing Activity but Does Not Protect against Challenge.

Arthropod-borne apicomplexan pathogens remain a great concern and challenge for disease control in animals and humans. In order to prevent infection, the discovery of antigens that elicit protective immunity is essential to establish approaches to stop disease dissemination. In this study, we determined that poly-N-acetylglucosamine (PNAG) is conserved among tick-borne pathogens including , , , and WA1.

Differential expression of calcium-dependent protein kinase 4, tubulin tyrosine ligase, and methyltransferase by xanthurenic acid-induced Babesia bovis sexual stages.

Background: Babesia bovis is one of the most significant tick-transmitted pathogens of cattle worldwide. Babesia bovis parasites have a complex lifecycle, including development within the mammalian host and tick vector. Each life stage has developmental forms that differ in morphology and metabolism.

Genes involved in immune, gene translation and chromatin organization pathways associated with Mycoplasma ovipneumoniae presence in nasal secretions of domestic sheep.

Mycoplasma ovipneumoniae contributes to polymicrobial pneumonia in domestic sheep. Elucidation of host genetic influences of M. ovipneumoniae nasal detection has the potential to reduce the incidence of polymicrobial pneumonia in sheep through implementation of selective breeding strategies.

A DNA Regulatory Element Haplotype at Zinc Finger Genes Is Associated with Host Resilience to Small Ruminant Lentivirus in Two Sheep Populations.

Small ruminant lentivirus (SRLV) causes Maedi-Visna or Ovine Progressive Pneumonia in sheep and creates insidious livestock production losses. This retrovirus is closely related to human immunodeficiency virus and currently has no vaccines or cure. Genetic marker assisted selection for sheep disease resiliency presents an attractive management solution.

Characterizing Genetic Regulatory Elements in Ovine Tissues.

The Ovine Functional Annotation of Animal Genomes (FAANG) project, part of the broader livestock species FAANG initiative, aims to identify and characterize gene regulatory elements in domestic sheep. Regulatory element annotation is essential for identifying genetic variants that affect health and production traits in this important agricultural species, as greater than 90% of variants underlying genetic effects are estimated to lie outside of transcribed regions. Histone modifications that distinguish active or repressed chromatin states, CTCF binding, and DNA methylation were used to characterize regulatory elements in liver, spleen, and cerebellum tissues from four yearling sheep.

Molecular and Serological Detection of Piroplasms in Horses from Nigeria.

Equine piroplasmosis, an economically important disease of equids caused by the hemoprotozoan parasites , , and , has a worldwide distribution. These parasites are transmitted by ixodid ticks. To improve the detection of horses in Nigeria exposed to piroplasm parasites, 72 horses with variable clinical signs of piroplasmosis were sampled from Northwest and Northcentral Nigeria and tested by nPCR and cELISA.

Genome-Wide Histone Modifications and CTCF Enrichment Predict Gene Expression in Sheep Macrophages.

Alveolar macrophages function in innate and adaptive immunity, wound healing, and homeostasis in the lungs dependent on tissue-specific gene expression under epigenetic regulation. The functional diversity of tissue resident macrophages, despite their common myeloid lineage, highlights the need to study tissue-specific regulatory elements that control gene expression. Increasing evidence supports the hypothesis that subtle genetic changes alter sheep macrophage response to important production pathogens and zoonoses, for example, viruses like small ruminant lentiviruses and bacteria like .

Association of and with Mature Weight in Sheep.

Signature of selection studies have identified many genomic regions with known functional importance and some without verified functional roles. Multiple studies have identified Transmembrane protein 8B ( as having been recently under extreme selection pressure in domesticated sheep, but no study has provided sheep phenotypic data clarifying a reason for extreme selection. We tested for production trait association in 770 U.

Transcriptome dataset of life stages within vertebrate and invertebrate hosts.

is a hemoprotozoan parasite of cattle that has a complex life cycle within vertebrate and invertebrate hosts. In the mammalian host, undergoes asexual reproduction while in the tick midgut, gametes are induced, fuse, and form zygotes. The zygote infects tick gut epithelial cells and transform into kinetes that are released into the hemolymph and invade other tick tissues such as the ovaries, resulting in transovarial transmission to tick offspring.

Assay to compare cell- and antibody-mediated immune responses in domestic sheep and goats.

Assessment of immune fitness is valuable in many aspects of livestock management and research. Determining immune consequences of selection for increased disease resistance or inhabiting various environments or climates can lead to different management decisions. The ability to measure immune responses due to different diets, pregnancy status, or aging will increase insight about how these factors contribute to overall immune health.

Comparative analysis of gene expression between Babesia bovis blood stages and kinetes allowed by improved genome annotation.

Throughout their life cycle, Babesia parasites alternate between a mammalian host, where they cause babesiosis, and the tick vector. Transition between hosts results in distinct environmental signals that influence patterns of gene expression, consistent with the morphological and functional changes operating in the parasites during their life stages. In addition, comparing differential patterns of gene expression among mammalian and tick parasite stages can provide clues for developing improved methods of control.

Quantitative analysis of Anaplasma marginale acquisition and transmission by Dermacentor andersoni fed in vitro.

In this study, we describe a new in vitro tick feeding system that facilitates the study of ticks and tick-borne pathogens. To optimize the system, we used Dermacentor andersoni and Anaplasma marginale as a tick-pathogen interaction model. Ticks were fed on bovine blood containing 10-fold dilutions of the pathogen to determine the effect of dose on tick infection rate.

Tissue inhibitor of metalloproteinase-1 and interleukin-10 in serum from naïve and scrapie infected sheep.

Tissue inhibitor of metalloproteinase-1 (TIMP-1) and interleukin-10 (IL-10) were identified as potential biomarkers for ovine scrapie in a mouse model. The development of novel diagnostic methods to identify pre-clinical scrapie-infected animals is needed. In this study, ELISA was used to assess TIMP-1 and IL-10 levels in 158 serum samples from naïve and preclinical scrapie-infected sheep.

Evaluation of Rambouillet, Polypay, and Romanov-White Dorper × Rambouillet ewes mated to terminal sires in an extensive rangeland production system: body weight and wool characteristics1,2.

Though lamb sales account for the majority of annual receipts on U.S. sheep operations, wool is an important income source for many Western flocks.

Effects of rearing triplet lambs on ewe productivity, lamb survival and performance, and future ewe performance.

Increasing prolificacy has been proposed to be the most effective way to increase the biological efficiency and profitability of sheep production. However, use of prolific breeds and genes with major effects on ovulation rate can increase prolificacy to levels that may not be desirable or sustainable in extensive rangeland production systems. This study thus evaluated effects of triplet births on ewe productivity and ewe and lamb performance.

Domestic sheep show average Coxiella burnetii seropositivity generations after a sheep-associated human Q fever outbreak and lack detectable shedding by placental, vaginal, and fecal routes.

Coxiella burnetii is a globally distributed zoonotic bacterial pathogen that causes abortions in ruminant livestock. In humans, an influenza-like illness results with the potential for hospitalization, chronic infection, abortion, and fatal endocarditis. Ruminant livestock, particularly small ruminants, are hypothesized to be the primary transmission source to humans.

Validation of an improved Anaplasma antibody competitive ELISA for detection of Anaplasma ovis antibody in domestic sheep.

An accurate and simple-to-perform new version of a competitive ELISA (cELISA) kit that became commercially available in 2015 for testing of cattle for antibody to Anaplasma marginale was validated for detection of Anaplasma ovis antibody in domestic sheep. True positives and negatives were identified using nested PCR (nPCR) as the gold standard. Negative bovine control sera supplied with the kit were used to calculate % inhibition (%I), designated bovine control ELISA (BcELISA), and this was compared to %I calculated from negative ovine sera derived from hand-raised, pathogen-free sheep, designated ovine control ELISA (OcELISA).