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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.
Show more [+] Less [-]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.
Show more [+] Less [-]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.
Show more [+] Less [-]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.
Leptin inhibits hepatocyte growth factor-induced ductal morphogenesis of bovine mammary epithelial cells
2007
Yamaji, D.(Hokkaido Univ., Sapporo (Japan)) | Kamikawa, A. | Soliman, M.M. | Ito, T. | Ahmed, M.M. | Makondo, K. | Watanabe, A. | Saito, M. | Kimura, K.
We examined the effect of stroma-derived factors, hepatocyte growth factor (HGF) and leptin, on morphological differentiation of bovine mammary epithelial cells (BMEC) in collagen gel three-dimensional culture in vitro. BMEC treated with HGF, but not leptin, formed duct-like organoids. The formation of organoids by HGF was enhanced by treatment with a mixture of insulin, cortisol and prolactin, while BMEC treated with the mixture alone did not produce the organoid. In contrast, the formation of organoids by HGF was dose-dependently inhibited by simultaneous addition of leptin, regardless of the presence or absence of the hormone mixture. These results suggest that stroma-derived factors intricately regulate mammary epithelial morphogenesis.
Show more [+] Less [-]Lumenal localization in the endoplasmic reticulum of the C-terminal tail of an AE1 mutant responsible for hereditary spherocytosis in cattle
2007
Ito, D.(Hokkaido Univ., Sapporo (Japan)) | Otsuka, Y. | Koshino, I. | Inaba, M.
An R664X nonsense mutant AE1 is responsible for dominant hereditary spherocytosis in cattle and is degraded by the proteasomal endoplasmic reticulum-associated degradation. The present study demonstrated that R664X AE1 translated in vitro had the trypsin-sensitve site identical to that of the wild-type AE1. The P661S/R664X mutant containing a possible N-glycosylation site at Asnsup(660) showed an increase in size by 3 kDa both in the cell-free translation system and in transfected HEK293 cells. Moreover, steady state levels of R664X and P661S/R664X in HEK293 cells were markedly increased in the presence of a proteasome inhibitior. These findings indicate that the truncated C-terminal region of R664X AE1 has lumenal localization in the endoplasmic reticulum and is not accessible to proteasomal machineries in the cytosol.
Show more [+] Less [-]Ecology and epidemiology of anthrax in cattle and humans in Zambia
2006
Siamudaala, V.M.(Zambia Wildlife Authority, Chilanga) | Bwalya, J.M. | Munag'andu, H.M. | Sinyangwe, P.G. | Banda, F. | Mweene, A.S. | Takada, A. | Kida, H.
Anthrax is endemic in Western and North-western Provinces of Zambia. The disease occurs throughout the year and impacts negatively on the economy of the livestock industry and public health in Zambia. During 1989-1995, there were 1,626 suspected cases of anthrax in cattle in Western province and of these 51 were confirmed. There were 220 cases of human anthrax cases in 1990 alone and 248 cases during 1991-1998 with 19.1% and 7.7% case fatality rates, respectively. Interplay of the ecology of affected areas and anthropogenic factors seem to trigger anthrax epidemics. Anthrax has drawn considerable attention in recent years due to its potential use as a biological weapon. In this paper, the history, current status and approaches towards the control of the disease in Zambia are discussed. Quarantine measures restrict trade of livestock and exchange of animals for draught power resulting in poor food security at household levels. Challenges of anthrax control are complex and comprise of socio-political, economical, environmental and cultural factors. Inadequate funding, lack of innovative disease control strategies and lack of cooperation from stakeholders are the major constraints to the control of the disease.
Show more [+] Less [-]Development of ELISA to detect antibodies specific to Mycobacterium avium subsp. paratuberculosis with truncated 34 kDa proteins
2006
Malamo, M.(Hokkaido Univ., Sapporo (Japan)) | Sakoda, Y. | Ozaki, H. | Kida, H.
To develop ELISA to detect antibodies specific to Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis), the carboxyl termini of the 34 kDa proteins of M. paratuberculosis and Mycobacterium avium subsp. avium (M. avium) were expressed in Escherichia coli expression system. Antibodies specific to M. paratuberculosis were detected with the truncated 34 kDa protein of M. paratuberculosis in ELISA after pre-absorption of serum samples with the truncated 34 kDa protein of M. avium. All the serum samples from cattle confirmed to be infected with M. paratuberculosis were positive and those from healthy cattle were negative in the present ELISA system. These results indicate that the established ELISA detects antibodies specific to M. paratuberculosis with high specificity and sensitivity and is an useful tool for the screening of Johne's disease.
Show more [+] Less [-]The prevalent genotypes of bovine viral diarrhea virus in Japan, Germany and the United States of America
2006
Tajima, M.(Hokkaido Univ., Sapporo (Japan))
Genotypes and subgenotypes of bovine viral diarrhea virus (BVDV) field isolates from Japan, Germany and the United States of America (USA) were identified, and the prevalent pattern of BVDV in individual countries was estimated genetically. Subgenotypes were determined based on phylogenetic analyses of nucleotide sequences of a part of the E2-coding gene of BVDV. Forty-five, 61 and 56 BVDV strains were isolated from naturally infected cattle in Japan, Germany and USA, respectively, between 1980 and 2003. The most prevalent BVDV in these three countries was BVDV - 1b. The second most prevalent BVDV strains were 1a, 1d and BVDV - 2 in Japan, Germany and USA, respectively. The most prevalent subgenotype 1b in each country constructed individual small clusters in the subgenotype 1b branch in the phylogenetic tree. Although cattle and/or cattle products were moving among the three countries as part of international trade, the distribution of BVDV in the field in each country showed long-standing individual patterns.
Show more [+] Less [-]Adrenocortical responses to tumor necrosis factor-alpha and interferon-gamma in cattle
2004
Soliman, M. (Hokkaido Univ., Sapporo (Japan)) | Okamoto, S. | Kitamura, H. | Kushibiki, S. | Kimura, K. | Saito, M.
The responses of plasma cortisol and adrenocorticotropic hormone (ACTH) were examined to intravenous injection of recombinant bovine tumor necrosis factor-alpha (TNF-alpha) and interferon-y (INF-gama) in Holstein cows. INF-gamain-duced dose-dependent rises in the plasma levels of both cortisol and ACTH, while TNF-alpha induced comparable plasma cortisol responses with much smaller rises in plasma ACTH. The results suggest a direct stimulatory action of TNF-alpha on cortisol secretion from the adrenal gland in cattle.
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