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Effects of anti-tick cocktail vaccine against Rhipicephalus appendiculatus
2008
Imamura, S.(Hokkaido Univ., Sapporo (Japan)) | Konnai, S. | da Silva Vaz, I.Jr. | Yamada, S. | Nakajima, C. | Ito, Y. | Tajima, T. | Yasuda, J. | Simuunza, M. | Onuma, M. | Ohashi, K.
Rhipicephalus appendiculatus serpin-3 (RAS-3), R. appendiculatus serpin-4 (RAS-4) and a 36kDa immuno-dominant protein of R. appendiculatus (RIM36) were reported as candidate antigens for the anti-tick vaccine to control ixodid ticks. In the present study, we generated recombinant proteins of RAS-3 (rRAS-3), RAS-4 (rRAS-4) and RIM36 (rRIM36), and assessed their potency as an anti-tick cocktail vaccine in cattle model. RT-PCR analysis showed that RAS-3, RAS-4 and RIM136 transcripts were detected in both adult male and female ticks during feeding. Immunization of cattle with the combination of rRAS-3, rRAS-4 and rRIM36 had raised antibodies against all recombinants and anti-sera had reacted with the molecules from the tick salivary gland extract. Tick infestation challenge demonstrated protective immunity against female ticks, resulting in mortality rates of 39.5 and 12.8 % for the vaccinated and control groups, respectively. Moreover, the mortality rate of Theileria parva-infected female ticks was 48.5 and 10.8 % in the vaccinated and control group, respectively. In order to evaluate the levels of pathogen transmission capacity by T. parva-infected ticks fed on immunized cattle, the occurrence of T. parva in the bovine parotid lymph node and peripheral blood was also determined and quantified by real-time PCR. Although the infection with T. parva could not be protected by the vaccine, the occurrence of pathogen in peripheral blood was delayed 1 to 2 days after the infestation challenge in vaccinated group. These results suggest that this cocktail vaccine plays a role in the prevention of tick infestation.
Afficher plus [+] Moins [-]Experimental transmission of bovine leukemia virus in cattle via rectal palpation
2006
Kohara, J.(Hokkaido. Animal Research Center, Shintoku (Japan)) | Konnai, S. | Onuma, M.
We examined whether Bovine leukemia virus (BLV) was transmitted by rectal palpation using a common sleeve between a BLV-infected cow and BLV- negative steers. Three of four steers developed antibodies against BLN as determined by agar-gel immunodiffusion (AGID) test between 7 to 10 weeks after the first rectal palpation using common sleeves from BLV-infected cow. In the steers, BLV proviral DNA were detected by PCR 1 to 5 weeks earlier than detection of the antibodies by the AGID test. Our experiments demonstrated that rectal palpation is a potential cause of BLV spread in herds and that detection of BLV proviral DNA in cattle by PCR is useful screening test for early diagnosis of BLV infection.
Afficher plus [+] Moins [-]Cloning and characterization of cDNA encoding a prohibitin-like protein from Theileria orientalis
2005
He, W.(Hokkaido Univ., Sapporo (Japan)) | Ohashi, K. | Sugimoto, C. | Tsuji, M. | Onuma, M.
A cDNA clone encoding a prohibitin-like protein (Toprh) was isolated from a piroplasm cDNA library of Theileria orientalis and its nucleotide sequence was determined. An open reading frame, encoding a polypeptide of 278 amino acid residues, was found in Toprh cDNA sequence. An intron of 89 bp was identified when this cDNA clone was compared with the Toprh gene in the genome of T. orientalis. The deduced amino acid sequence of Toprh shares 93.8, 93.1 and 69.1% identities with the prohibitins of T. parva (from chromosome 1), T. annulata (from chromosome 1), and Plasmodium falciparum, (from chromosome 10), respectively. By Western blot analysis, Toprh was found to be expressed in the piroplasm stage of the parasites.
Afficher plus [+] Moins [-]A survey of abomasal and duodenal nematodes in cattle in Hokkaido, Japan
1987
Oku, Y. (Hokkaido Univ., Sapporo (Japan). Faculty of Veterinary Medicine) | Nakazawa, M. | Hatakeyama, S. | Miyaji, S. | Kitaguchi, T. | Cabrera-Lopez, C.A. | Okamoto, M. | Kamiya, M. | Ohbayashi, M. | Ooi, H.K.
Availability of oral swab sample for the detection of bovine viral diarrhea virus (BVDV) gene from the cattle persistently infected with BVDV
2008
Tajima, M.(Hokkaido Univ., Sapporo (Japan)) | Ohsaki, T. | Okazawa, M. | Yasutomi, I.
Bovine nasal and oral discharges were used as samples for bovine viral diarrhea virus (BVDV) gene detection. Viral genes in serum (S), nasal discharge (N) and oral discharge (O) were quantified with real-time polymerase chain reaction using SYBR Green by the relative quantification method, and findings were compared among samples. Although the quantity of the BVDV gene in S was greater than those in N and O, all samples were available to identify persistently infected (PI) cattle with BVDV by reverse transcription polymerase chain reaction (RT-PCR). The swab samples were able to be stored for a few days at 4degC with a little decrease of amplification signal in RT-PCR. Oral swab sampling was easier than nasal swab sampling, and was also less uncomfortable for the cattle than other sampling methods without pain or unnecessary retention. This sampling method can be performed without any special technique and equipment. Therefore, the oral swab sampling method is useful for screening to detect BVDV PI cattle by RT-PCR.
Afficher plus [+] Moins [-]Oxidative stress and bovine liver diseases: Role of glutathione peroxidase and glucose 6-phosphate dehydrogenase
2007
Ellah, M.R.A.(Iwate Univ., Morioka (Japan). Faculty of Agriculture) | Okada, K. | Yasuda, J.
This article summarizes the different types of free radicals, antioxidants and the effect of oxidative stress on the activities of glutathione peroxidase and glucose 6-phosphate dehydrogenase in bovine liver diseases. A growing body of evidence suggests that the formation of reactive oxygen species is a common occurrence associated with most if not all disease processes. The overall importance of reactive oxygen species to the progression and severity of various disease states varies greatly depending on the conditions and whether the disease is acute or chronic. Free radical researches in animals are in progress and further investigations are needed to establish the involvement of reactive oxygen species in diseases affecting different animal species and the pathology they produce.
Afficher plus [+] Moins [-]Gene expression profile of bovine bone marrow mesenchymal stem cell during spontaneous chondrogenic defferentiation in pellet culture system
2006
Bosnakovski, D.(Hokkaido Univ., Sapporo (Japan)) | Mizuno, M. | Kim, G. | Takagi, S. | Okumura, M. | Fujinaga, T.
Bovine bone marrow mesenchymal stem cells (MSCs) cultured in condensate culture, spontaneous and independent for any external biostimulants, undergo chondrogenic differentiation. In the present study, the bovine MSC chondrogenesis pathway was studied by analyzing stage-specific gene expression using quantitative 'Real Time' reverse transcriptase polymerase chain reaction (qRT-PCR). Results showed that bovine MSCs underwent complete chondrogenesis; the initial stage was characterized by expression of sox 9 messenger ribonucleic acid (mRNA), followed by high transcription of chondrocyte specific genes, collagen type II and IX, biglycan and cartilage oligomeric matrix protein, and the final prehypertrophic and/or hypertrophic stage was distinguished by increased expression of collagen type X. From day 7 to day 14 of differentiation increased mRNA expression of the transforming growth factors beta1 and beta2, basic fibroblast growth factor (FGF 2), bone morphogenic protein 6 (BMP 6), insulin-like growth factors 1, parathyroid hormone related peptide and indian hedgehog (Ihh) were detected. These results suggest that these well know chondrogenic growth factors may play a role in bovine chondrogenesis in autocrine and/or paracrine manner. On day 21 of the culture, FGF 2, BMP 6 and Ihh were highly expressed, compared to cells cultured in monolayer manner, which suggests a possible function in maintaining the terminal stage of differentiation. This data extends our knowledge about the unusual species-specific bovine MSC chondrogenesis, allowing us to define the phenotype of the differentiated cells. Furthermore, this study contributes to our in understanding of known chondrogenic-growth factors in autocrine and/or paracrine manner playing a role in the spontaneous differentiation.
Afficher plus [+] Moins [-]Bovine clostridial infections in Zambia (1985-1994)
1996
Munang'andu, H.M. (Central Veterinary Research Inst., Lusaka (Zambia)) | Muyoyeta, P.M. | Mweene, A.S. | Kida, H.
Attempt to eradicate bovine leukemia virus infected cattle from herds
1992
Wang, C.T. (National Taiwan Univ., Taipei (Taiwan)) | Onuma, M.
Analysis of tissue creatine phosphokinase isoenzymes by histoelectrophoresis
1985
Yasuda, J. (Hokkaido Univ., Sapporo (Japan). Faculty of Veterinary Medicine) | Syuto, B. | Too, K.