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Introduction: Targeted single nucleotide polymorphisms (SNPs) have been used in genomic prediction methodologies to enhance the accuracy of associated genetic transmitting abilities in Holstein cows. The objective of this study was to identify and validate SNPs associated with fertility traits impacting early embryo mortality. Methods: The mRNA sequencing data from day 16 normal (n = 9) and embryo mortality (n = 6) conceptuses from lactating multiparous Holstein cows were used to detect SNPs. The selection of specific genes with SNPs as preliminary candidates was based on associations with reproductive and fertility traits. Validation of candidate SNPs and genotype-to-phenotype analyses were conducted in a separate cohort of lactating primiparous Holstein cows (n = 500). After genotyping, candidate SNPs were filtered using a quality control pipeline via PLINK software. Continuous numeric and binary models from reproductive traits were evaluated using the mixed procedure for a generalized linear model-one way ANOVA or logistic regression, respectively. Results: Sixty-nine candidate SNPs were initially identified, but only 23 passed quality control procedures. Ultimately, the study incorporated 466 observations for statistical analysis after excluding animals with missing genotypes or phenotypes. Significant (p <0.05) associations with fertility traits were identified in seven of the 23 SNPs: DSC2 (cows with the A allele were older at first calving); SREBF1 and UBD (cows with the T or G alleles took longer to conceive); DECR1 and FASN (cows with the C allele were less likely to become pregnant at first artificial insemination); SREBF1 and BOLA-DMB (cows with the T allele were less likely to be pregnant at 150 days in milk). It was also determined that two candidate SNPs within the DSC2 gene were tag SNPs. Only DSC2 SNPs had an important allele substitution effect in cows with the G allele, which had a decreased age at first calving by 10 days. Discussion: Candidate SNPs found in this study could be used to develop genetic selection tools to improve fertility traits in dairy production systems. [ABSTRACT FROM AUTHOR]

Bovine viral diarrhea virus (BVDV) infections cause USD 1.5–2 billion in losses annually. Maternal BVDV after 150 days of gestation causes transient fetal infection (TI) in which the fetal immune response clears the virus. The impact of fetal TI BVDV infections on postnatal growth and white blood cell (WBC) methylome as an index of epigenetic modifications was examined by inoculating pregnant heifers with noncytopathic type 2 BVDV or media (sham-inoculated controls) on Day 175 of gestation to generate TI (n = 11) and control heifer calves (n = 12). Fetal infection in TI calves was confirmed by virus-neutralizing antibody titers at birth and control calves were seronegative. Both control and TI calves were negative for BVDV RNA in WBCs by RT-PCR. The mean weight of the TI calves was less than that of the controls (p < 0.05). DNA methyl seq analysis of WBC DNA demonstrated 2349 differentially methylated cytosines (p ≤ 0.05) including 1277 hypomethylated cytosines, 1072 hypermethylated cytosines, 84 differentially methylated regions based on CpGs in promoters, and 89 DMRs in islands of TI WBC DNA compared to controls. Fetal BVDV infection during late gestation resulted in epigenomic modifications predicted to affect fetal development and immune pathways, suggesting potential consequences for postnatal growth and health of TI cattle. [ABSTRACT FROM AUTHOR]

Bovine viral diarrhea virus (BVDV) infection during early gestation results in persistently infected (PI) immunotolerant calves that are the primary reservoirs of the virus. Pathologies observed in PI cattle include congenital defects of the brain, heart, and bone as well as marked functional defects in their immune system. It was hypothesized that fetal BVDV infection alters T cell activation and signaling genes by epigenetic mechanisms. To test this, PI and control fetal splenic tissues were collected on day 245 of gestation, 170 days post maternal infection. DNA was isolated for reduced representation bisulfite sequencing, protein was isolated for proteomics, both were analyzed with appropriate bioinformatic methods. Within set parameters, 1951 hypermethylated and 691 hypomethylated DNA regions were identified in PI compared to control fetuses. Pathways associated with immune system, neural, cardiac, and bone development were associated with heavily methylated DNA. The proteomic analysis revealed 12 differentially expressed proteins in PI vs. control animals. Upregulated proteins were associated with protein processing, whereas downregulated proteins were associated with lymphocyte migration and development in PI compared to control fetal spleens. The epigenetic changes in DNA may explain the immune dysfunctions, abnormal bone formation, and brain and heart defects observed in PI animals. [ABSTRACT FROM AUTHOR]

Investigating the influences of single nucleotide polymorphisms (SNP) associated with conceptus death (CD) on day 16 of pregnancy could distinguish cows who have inferior value for fertility traits. We hypothesized that CD is associated with SNP genotypes that disrupt maternal recognition and lead to early pregnancy loss. RNA sequences from Holstein cow pregnancies (n = 15) with normal conceptuses (Norm) or CD were subjected to SNP discovery via Qiagen CLC Genomics Workbench. Selected SNP were based on previous fertility studies, differentially expressed genes within pregnancy development analyses and proximity to SNP associated with fertility traits in the Cattle QTL Database. A second cohort of Holstein cows (n = 500) was used to conduct a validation and genotype to phenotype analysis of candidate SNP (cSNP) via DNA from blood samples and farm records. PLINK software was used to remove cows (n = 34) missing more than ≥20% cSNP and remove cSNP with monomorphic alleles, minor allele frequency (MAF) < 10% and not in Hardy-Weinberg Equilibrium (>1e-15). The GLM-one way ANOVA was used for all statistical models in SAS. Statistically significant models (P <0.05) were further analyzed for LSMEANS, Bonferroni adjustment of P-values, additive allele effect and predicted effect of amino acid (aa) change on protein function via SIFT analyses tool in the Ensembl variant table (scoring 0-1.0; ≥ 0.05 being significant). Previously, we identified 69 cSNP on the RNA sequences of Norm or CD pregnancies from the initial group of Holstein cows and in proximity to ≥1 SNP associated with fertility traits from the Cattle QTL database. Quality control measures in PLINK reduced the number of Holstein cows in the second cohort to 466 and identified 4 cSNP associated with non-binary reproductive traits. Herein, we report an additional 4 cSNP discovered and validated with binary reproductive traits. The cSNP within genes were associated with the following roles: BOLADMB (antigen loading in the immune system), DECR1 (lipid metabolism), FASN (reconstitution of body reserves during pregnancy) and SREBF1 (synthesis of fatty acids). Cows with T allele, in BOLA-DMB and SREBF1, were less likely (P < 0.05) to become pregnant ≤150 days in milk (DIM). For DECR1 and FASN, cows were less likely (P < 0.05) to become pregnant at 1st artificial insemination with C or A allele, respectively. Only the cSNP in SREBF1 had both an additive allele effect and a predicted effect of aa change on protein function. When cows had C allele, in the SREBF1 cSNP, there was 6% greater (P < 0.01) probability of becoming pregnant <150 DIM. While SIFT revealed the cSNP in SREBF1 have a predicted significant effect with a score of 0.03 for the aa change of proline/leucine. The reported cSNP, specifically those influenced by CD, add valuable information for the development of improved genetic tools for the dairy industry. USDA-NIFA#2019-07133. [ABSTRACT FROM AUTHOR]

Infection of pregnant cows with noncytopathic (ncp) bovine viral diarrhea virus (BVDV) induces rapid innate and adaptive immune responses, resulting in clearance of the virus in less than 3 weeks. Seven to 14 days after inoculation of the cow, ncpBVDV crosses the placenta and induces a fetal viremia. Establishment of persistent infection with ncpBVDV in the fetus has been attributed to the inability to mount an immune response before 90–150 days of gestational age. The result is ‘immune tolerance’, persistent viral replication and shedding of ncpBVDV. In contrast, we describe the chronic upregulation of fetal Type I interferon (IFN) pathway genes and the induction of IFN-γ pathways in fetuses of cows infected on day 75 of gestation. Persistently infected (PI) fetal IFN-γ concentrations also increased at day 97 at the peak of fetal viremia and IFN-γ mRNA was significantly elevated in fetal thymus, liver and spleen 14–22 days post maternal inoculation. PI fetuses respond to ncpBVDV infection through induction of Type I IFN and IFN-γ activated genes leading to a reduction in ncpBVDV titer. We hypothesize that fetal infection with BVDV persists because of impaired induction of IFN-γ in the face of activated Type I IFN responses. Clarification of the mechanisms involved in the IFN-associated pathways during BVDV fetal infection may lead to better detection methods, antiviral compounds and selection of genetically resistant breeding animals. [ABSTRACT FROM PUBLISHER]

An epizootic of hemorrhagic disease associated with Epizootic hemorrhagic disease virus serotype 2 (EHDV-2) infections in yaks from 5 herds occurred in Colorado between August 21 and October 3, 2012. Affected yaks presented with fever, lethargy, anorexia, dyspnea, and swollen conjunctivae. Ulcerated dental pads, mucoid sanguineous nasal discharge, petechial hemorrhages in multiple organs, pulmonary edema, and serosanguinous fluid in the thorax, abdomen, and pericardial sac were observed at necropsy. Blood and tissue samples from 8 yaks with similar clinical signs and necropsy findings were positive for EHDV-2 by reverse transcription polymerase chain reaction and 5 yaks were seropositive for EHDV. Tests for malignant catarrhal fever (Ovine herpesvirus 2), Bovine viral diarrhea virus, Bovine herpesvirus 1, Foot-and-mouth disease virus, and Vesicular stomatitis virus were negative. The findings indicate that yaks are susceptible to infection with EHDV-2 and exhibit the clinical signs, and gross and histologic lesions of hemorrhagic disease observed in other ruminant species. [ABSTRACT FROM PUBLISHER]

The article reports on the Hepatopancreatic rickettsial infection of the penaeid shrimp. Frozen Penaeus (P.) marginatus tissues were screened for pathogens by shrimp bioassay. Preserved shrimp were processed for routine histopathology and stained with haematoxyiin and eosin. The rickettsial agent from P. marginatus was found to be highly infectious for juvenile P. stylirostris. Based on the data presented, P. stylirostris bioassay would appear to be of use as a method to determine the presence of this rickettsia in wild-caught P. marginatus, and juvenile P. stylirostris could be used as a suitable host for experimental culture of this rickettsia under laboratory conditions.

Two adult female bison, housed in an outdoor research facility and observed daily, died suddenly three days apart. Minimal coordination and behavioral changes were observed in one animal the evening before being found in a moribund state.Malignant catarrhal fever was suspected in both bison due to a recent confirmed MCF case with similar course. The cause of death was not apparent from necropsy, but brains of both animals were strongly positive for rabies virus antigen by fluorescent antibody and/or immunohistochemical tests. Minimal to mild encephalitis with Negri bodies was observed on histopathology. The bison were located in an area that had not been endemic for skunk rabies; however, a case of rabies in a skunk had been discovered 1.6 km north of the bison paddock two months prior to the bison cases. [ABSTRACT FROM AUTHOR]

Maternal influenza A viral infections in humans are associated with low birth weight, increased risk of pre-term birth, stillbirth and congenital defects. To examine the effect of maternal influenza virus infection on placental and fetal growth, pregnant C57BL/6 mice were inoculated intranasally with influenza A virus A/CA/07/2009 pandemic H1N1 or phosphate-buffered saline (PBS) at E3.5, E7.5 or E12.5, and the placentae and fetuses collected and weighed at E18.5. Fetal thymuses were pooled from each litter. Placentae were examined histologically, stained by immunohistochemistry (IHC) for CD34 (hematopoietic progenitor cell antigen) and vascular channels quantified. RNA from E7.5 and E12.5 placentae and E7.5 fetal thymuses was subjected to RNA sequencing and pathway analysis. Placental weights were decreased in litters inoculated with influenza at E3.5 and E7.5. Placentae from E7.5 and E12.5 inoculated litters exhibited decreased labyrinth development and the transmembrane protein 150A gene was upregulated in E7.5 placentae. Fetal weights were decreased in litters inoculated at E7.5 and E12.5 compared to controls. RNA sequencing of E7.5 thymuses indicated that 957 genes were downregulated ≥2-fold including Mal, which is associated with Toll-like receptor signaling and T cell differentiation. There were 28 upregulated genes. It is concluded that maternal influenza A virus infection impairs fetal thymic gene expression as well as restricting placental and fetal growth. [ABSTRACT FROM AUTHOR]

Bovine Viral Diarrhea Virus (BVDV) fetal infections occur in two forms; persistent infection (PI) or transient infection (TI), depending on what stage of gestation the fetus is infected. Examination of lymphoid organs from both PI and TI fetuses reveals drastically different fetal responses, dependent upon the developmental stage of the fetal immune system. Total RNA was extracted from the thymuses and spleens of uninfected control, PI, and TI fetuses collected on day 190 of gestation to test the hypothesis that BVDV infection impairs the innate and adaptive immune response in the fetal thymus and spleen of both infection types. Transcripts of genes representing the innate immune response and adaptive immune response genes were assayed by Reverse Transcription quatitative PCR (RT-qPCR) (2−ΔΔCq; fold change). Genes of the innate immune response, interferon (IFN) inducible genes, antigen presentation to lymphocytes, and activation of B cells were downregulated in day 190 fetal PI thymuses compared to controls. In contrast, innate immune response genes were upregulated in TI fetal thymuses compared to controls and tended to be upregulated in TI fetal spleens. Genes associated with the innate immune system were not different in PI fetal spleens; however, adaptive immune system genes were downregulated, indicating that PI fetal BVDV infection has profound inhibitory effects on the expression of genes involved in the innate and adaptive immune response. The downregulation of these genes in lymphocytes and antigen-presenting cells in the developing thymus and spleen may explain the incomplete clearance of BVDV and the persistence of the virus in PI animals while the upregulation of the TI innate immune response indicates a more mature immune system, able to clear the virus. [ABSTRACT FROM AUTHOR]

This article reports the occurrence of B. penaei in an additional host species, Penaeus marginatus Randall, and geographical area, Hawaii. Penaeus marginatus or Opai Lolo is the only member of the genus Penaeus indigenous to the Hawaiian Islands. Additional juvenile (01 to 4-0 g) P. marginatus were collected from the Kuliouou tidal flats from January to March 1984. These shrimp were held in aquaria for 7-10 days prior to examination. Shrimp were sacrificed by injection and immersion in Davidson's fixative, and after 24 h transferred to 50% ethanol for storage. Preserved hepatopancreata were processed for routine histopathology and stained with haematoxylin and eosin.

Abstract: Bovine viral diarrhea virus (BVDV) infection occurs in the cattle population worldwide. Non-cytopathic (ncp) BVDV strains cause transient infection (TI) or persistent infection (PI) depending on the host''s immune status. Immunocompetent adult animals and fetuses in late gestation resolve the infection. Fetal infection in early gestation results in PI with chronic viremia and life-long viral shedding, ensuring virus perpetuation in the population. Eighteen pregnant heifers, divided into three groups, were intranasally inoculated with ncp BVDV2 virus early (day 75) and late (day 175) in gestation, or kept BVDV-naïve. Fetuses were retrieved on day 190. Antiviral activity in blood of dams and fetuses, maternal expression of interferon (IFN) stimulated gene 15kDa (ISG15), virological and serological status of heifers and fetuses, and fetal growth were studied. A pronounced antiviral activity in blood of heifers and TI fetuses during acute BVDV infection was accompanied by drastic up-regulation of ISG15 mRNA in maternal blood. Only one PI fetus expressed low IFN response 115 days post inoculation despite high BVDV antigen and RNA levels. PI fetuses presented with growth retardation. Infection of pregnant heifers with ncp BVDV2 early in gestation adversely affects fetal development and antiviral responses, despite protective immune responses in the dam. [Copyright &y& Elsevier]

Objective--To assess the impacts of the introduction of foot-and-mouth disease (FMD) and various FMD control programs in southern Thailand. Animals--A native population of 562,910 cattle and 33,088 buffalo as well as 89,294 animals legally transported into southern Thailand. Procedures--A quantitative risk assessment was used to ascertain the probability of FMD introduction, and an intrinsic dynamic model was used to assess impacts. Value for the transmission rate (β) was estimated. Five scenarios created to assess the impacts of nonstructural protein (NSP) testing, mass vaccination, and culling were examined. Impacts were assessed through an examination of the estimated annual cumulative incidence (ACI) of FMD. The ACls of various scenarios were compared by use of the Tukey Studentized range technique. Results--β was estimated at 0.115. Approximately 35,000 cases of FMD would be expected from the baseline situation. A 30% reduction of ACI was detected with the introduction of NSP antibody testing. Prophylactic vaccination resulted in an 85% reduction of ACl. Concurrent use of NSP antibody testing and vaccination reduced the ACl by 96%, and the addition of an eradication policy resulted in a slightly greater decrease in the ACl (98%). Conclusions and Clinical Relevance--The study used epidemiologic models to investigate FMD control interventions. Results suggested that vaccination has more impact than the use of NSP testing. Use of the NSP test reduced ACl during peak seasons, whereas vaccination diminished the underlying incidence. The best mitigation plan was an integrated and strategic use of multiple control techniques. [ABSTRACT FROM AUTHOR]

Objective--To assess the likelihood of an introduction of foot-and-mouth disease (FMD) into the Malaysia-Thailand-Myanmar (MTM) peninsula through terrestrial movement of livestock. Animals--89,294 cattle and buffalo legally moved into the MTM peninsula. Procedures--A quantitative risk assessment was conducted by use of a stochastic simulation. Patterns of livestock movement were ascertained through review of relevant governmental records and regulations and by interviewing farmers, traders, and local officers when the records did not exist. Parameters identified in the process were the probabilities of livestock having FMD and of FMD infection going undetected during import processes. The probability of an animal accepted for import having FMD was also assessed. Sensitivity analysis was performed to determine the effects that each parameter had on the model. Results--The simulation yielded an average consignment prevalence of 10.95%. Typically, each animal in a quarantine facility had a 2.7% chance of having an inapparent form of FMD infection; hence, it was likely an animal would not be identified as infected. Findings revealed that the mean probability of an animal accepted for import having FMD was 2.9%, and the risk was as high as 11%. Conclusions and Clinical Relevance--Results of the model allowed for the evaluation of movement regulations currently imposed in the MTM peninsula. Evidence from the study suggested that current practices in animal movement were far from efficient in preventing introduction of FMD-infected animals into the MTM region, and additional measures will be necessary. [ABSTRACT FROM AUTHOR]

Objective—To describe the prevalence of West Nile virus (WNV) infection and evaluate factors associated with positive IgM capture ELISA results in equids with clinical signs compatible with WNV infection. Design—Retrospective case series. Sample Population—Laboratory submission forms from 1,104 equids tested for WNV in Colorado in 2003. Procedures--Submission forms accompanying samples submitted for detection of WNV via IgM capture ELISA were obtained from the Colorado state veterinarian and diagnostic laboratories performing the tests. Data on signalment, clinical signs, history of vaccination against WNV, and assay results were collected from laboratory submission forms. Equids with clinical signs compatible with WNV infection in which IgM capture ELISA results were positive were considered as case equids. Results—1,104 equids were tested for WNV; 1,017 (92.1%) had clinical signs compatible with WNV infection. Among equids with clinical signs compatible with WNV infection, the odds of testing positive for WNV via IgM capture ELISA were lower in males and in vaccinated equids and higher in equids with moderate and severe illness, compared with females, unvaccinated equids, and equids with mild illness. Conclusions and Clinical Relevance—Among equids with clinical signs compatible with WNV infection, vaccination against WNV, severity of clinical signs, duration of illness, and region in Colorado were associated with increased risk of having a positive IgM capture ELISA result. [ABSTRACT FROM AUTHOR]