Kinetic Study of BLV Infectivity in BLV Susceptible and Resistant Cattle in Japan from 2017 to 2019.

Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis. Polymorphism in bovine lymphocyte antigen alleles is related to susceptibility to BLV proviral load (PVL), which is a useful index for estimating disease progression and transmission risk. However, whether differential affects BLV infectivity remains unknown.

Insulin-like growth factor-1 induces IRE1-XBP1-dependent endoplasmic reticulum biogenesis in bovine mammary epithelial cells.

Insulin-like growth factor-1 (IGF-1) plays a key role in proliferation and galactopoiesis in mammary epithelial cells (MEC), but its definitive functions on endoplasmic reticulum (ER) during protein synthesis remain unknown. The present study aimed to elucidate the effects of IGF-1 on ER biogenesis in MEC in vitro and examined the expression of ER biogenesis-associated genes in the mammary gland during early lactation. We treated mammary alveolar cells-large T antigen cells (immortalized bovine MEC line established via stable transfection with simian virus-40 large T-antigen) with IGF-1 and examined ER biogenesis using the fluorescence intensity of an ER tracker and quantitative real-time PCR.

The Physiological Roles of Vitamin E and Hypovitaminosis E in the Transition Period of High-Yielding Dairy Cows.

Levels of alpha-tocopherol (α-Toc) decline gradually in blood throughout prepartum, reaching lowest levels (hypovitaminosis E) around calving. Despite numerous reports about the disease risk in hypovitaminosis E and the effect of α-Toc supplementation on the health of transition dairy cows, its risk and supplemental effects are controversial. Here, we present some novel data about the disease risk of hypovitaminosis E and the effects of α-Toc supplementation in transition dairy cows.

Heart rate variability in dairy cows with postpartum fever during night phase.

Autonomic nervous function evaluated by heart rate variability (HRV) and blood characteristics were compared between Holstein Friesian cows that developed postpartum fever (PF; n = 5) and clinically healthy (CH; n = 6) puerperal cows in this case-control study. A cow was defined as having PF when its rectal temperature rose to ≥39.5°C between 1 and 3 days postpartum.

Visualizing bovine leukemia virus (BLV)-infected cells and measuring BLV proviral loads in the milk of BLV seropositive dams.

Bovine leukemia virus (BLV) infects cattle and causes serious problems for the cattle industry, worldwide. Vertical transmission of BLV occurs via in utero infection and ingestion of infected milk and colostrum. The aim of this study was to clarify whether milk is a risk factor in BLV transmission by quantifying proviral loads in milk and visualizing the infectivity of milk.

A sensitive luminescence syncytium induction assay (LuSIA) based on a reporter plasmid containing a mutation in the glucocorticoid response element in the long terminal repeat U3 region of bovine leukemia virus.

Background: Bovine leukemia virus (BLV) causes enzootic bovine leukosis, the most common neoplastic disease of cattle. Previously, we reported the luminescence syncytium induction assay (LuSIA), an assay for BLV infectivity based on CC81-BLU3G cells, which form syncytia expressing enhanced green fluorescent protein (EGFP) when co-cultured with BLV-infected cells. To develop a more sensitive LuSIA, we here focused on the glucocorticoid response element (GRE) within the U3 region of the BLV long terminal repeat (LTR).

The effectiveness of colostral antibodies for preventing bovine leukemia virus (BLV) infection in vitro.

Background: Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis (EBL). The incidence of EBL in Japan is increasing annually; and the cases of EBL in cattle younger than 2 years old has been reported. Therefore, it is vital to find a method to control BLV infection, especially in young calves.

Development of a new recombinant p24 ELISA system for diagnosis of bovine leukemia virus in serum and milk.

Bovine leukemia virus (BLV) is a retrovirus that causes enzootic bovine leucosis. Here, we designed a p24 enzyme-linked immunosorbent assay (ELISA) to detect antibodies specific for BLV capsid protein p24 (encoded by the gag gene) in bovine serum samples. The p24 gene was inserted into an Escherichia coli expression system, and recombinant proteins (GST-p24, p24, and His-p24) were purified.

Comparative transcriptome analysis of rumen papillae in suckling and weaned Japanese Black calves using RNA sequencing.

The length and density of rumen papillae starts to increase during weaning and growth of ruminants. This significant development increases the intraruminal surface area and the efficiency of VFA (acetate, propionate, butyrate, etc.) uptake.

Development of a luminescence syncytium induction assay (LuSIA) for easily detecting and quantitatively measuring bovine leukemia virus infection.

Bovine leukemia virus (BLV) causes enzootic bovine leukosis and is closely related to the human T cell leukemia virus. Since BLV infection mostly occurs via cell-to-cell transmission, BLV infectivity is generally measured by culturing BLV-infected cells with reporter cells that form syncytia upon BLV infection. However, this method is time-consuming and requires skill.

The unfolded protein response is involved in both differentiation and apoptosis of bovine mammary epithelial cells.

The unfolded protein response (UPR) describes a process involved in the homeostasis of endoplasmic reticulum (ER) and the differentiation of secretory cells. At present, the roles of UPR in the mammary gland tissue of dairy cattle are unknown. In the current study, we investigated the expression of UPR-related genes in Holstein cows during the developmental and lactating stages of the mammary gland tissue.

Development of a direct blood-based PCR system to detect BLV provirus using CoCoMo primers.

Bovine leukemia virus (BLV), the etiologic agent of enzootic bovine leucosis, has caused pandemic outbreaks worldwide. Because transcription of the BLV is quickly blocked after infection, detecting integrated provirus at host genome is an important method of identifying whether an animal is infected. The aim of the present study was to develop a novel direct blood-based PCR system to detect the BLV provirus with high specificity and at low cost.

Utilization of digital differential display to identify differentially expressed genes related to rumen development.

This study aimed to identify the genes associated with the development of the rumen epithelium by screening for candidate genes by digital differential display (DDD) in silico. Using DDD in NCBI's UniGene database, expressed sequence tag (EST)-based gene expression profiles were analyzed in rumen, reticulum, omasum, abomasum and other tissues in cattle. One hundred and ten candidate genes with high expression in the rumen were derived from a library of all tissues.

Seasonal foraging patterns of forest-grazing Japanese Black heifers with increased plasma total antioxidant capacity.

Forest-grazing enables the intake of high total antioxidant capacity (TAC) plants that might be beneficial for the TAC status of cattle. This study evaluated the relation between the seasonal foraging patterns of forest-grazing Japanese Black (JB) heifers or the TAC levels in shrubs and trees and the changes of plasma TAC. We examined 12 JB heifers, four each of which were allocated to forest-grazing (F), pasture-grazing, and pen-housed groups.

Increase in plasma total antioxidant capacity of grazing Japanese Black heifers and cows in forestland in Japan.

Blood total antioxidant capacity (TAC) has become a key bio-marker for animal health. Forest-grazing cattle are known to forage various native plants that have high TAC. This study evaluated differences of plasma TAC between forest-grazing (FG) and pasture-grazing cattle (PG).

Estimation of bovine leukemia virus (BLV) proviral load harbored by lymphocyte subpopulations in BLV-infected cattle at the subclinical stage of enzootic bovine leucosis using BLV-CoCoMo-qPCR.

Background: Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis (EBL), which is the most common neoplastic disease of cattle. BLV infection may remain clinically silent at the aleukemic (AL) stage, cause persistent lymphocytosis (PL), or, more rarely, B cell lymphoma. BLV has been identified in B cells, CD2+ T cells, CD3+ T cells, CD4+ T cells, CD8+ T cells, γ/δ T cells, monocytes, and granulocytes in infected cattle that do not have tumors, although the most consistently infected cell is the CD5+ B cell.

Molecular epidemiology of Trichophyton tonsurans strains isolated in Japan between 2006 and 2010 and their susceptibility to oral antimycotics.

Trichophyton tonsurans has been isolated among judo practitioners, wrestlers, and sumo wrestlers during an epidemic of tinea corporis and tinea capitis in Japan. A previous study using restriction fragment length polymorphism (RFLP) analysis of the non-transcribed spacer (NTS) region of the ribosomal RNA gene revealed that different sources for the causative fungus in epidemics among judo practitioners and among wrestlers. Many different fungal strains have since been isolated from practitioners of these sports.

New strain typing method with Sporothrix schenckii using mitochondrial DNA and polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) technique.

The complete sequences of mitochondrial DNA (mtDNA) from two strains of different genotypes, American Type Culture Collection 10268 of mtDNA type 1 and KMU2025 of mtDNA type 4, were determined. These are circular molecules, 27 125 and 26 095 bp in length, respectively. The greatest difference between the two strains was found in the region encompassed by atp9 and cox2 genes, which was amplified with polymerase chain reaction (PCR) and used for preliminary restriction fragment length polymorphism (RFLP) analysis.

Matings among three teleomorphs of Trichophyton mentagrophytes.

Three genetically hybrid F1 progenies produced between a clinical isolate of Arthroderma simii (KMU4810) and a tester strain of A. vanbreuseghemii (RV27961) were crossed with two tester strains of A. vanbreuseghemii (RV27961 and RV27960) and a tester strain of A.

Successful mating of Trichophyton rubrum with Arthroderma simii.

Crossing of Trichophyton rubrum with Arthroderma simii yielded many ascomata around the fluffy T. rubrum colonies. One of the 35 supposed ascospores isolated from matured ascoma was shown to be a hybrid of the two species.

Road transportation stress promptly increases bovine peripheral blood absolute NK cell counts and cortisol levels.

Livestock transportation effects on the number of circulating leukocytes have been reported. However, data related specifically to the relation between acute stress levels during transport and leukocyte differentiation, including lymphocyte subsets, are lacking. This study was undertaken to evaluate the distribution of peripheral blood leukocyte differential counts, CD25+ lymphocytes and NK cells in calves subjected to truck transportation on different road types.

Mitochondrial DNA analysis of Sporothrix schenckii in India, Thailand, Brazil, Colombia, Guatemala and Mexico.

Up to now, 30 mitochondrial DNA(mtDNA)and 4 rDNA types of Sporothrix schenckii strains have been identified. Here, seventy-six isolates of S. schenckii from Mexico, Guatemala, Brazil, Thailand and India were genotyped and studied epidemiologically by mtDNA restriction fragment length polymorphisms(RFLP)and internal transcribed spacer region(ITS)-RFLP analysis and two new mtDNA types, Type 31 and Type 32, were found.

Successful mating of a human isolate of Arthroderma simii with a tester strain of A. vanbreuseghemii.

An isolate of Arthroderma simii was successfully mated with a tester strain of A. vanbreuseghemii cultured on the plate of simple agar with some hair on it at 27 degrees C. Confirmation of sexual reproduction was made by the detection of hybrids of two parental genotypes.