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A seroepidemiological study of bovine immunodeficiency virus (BIV) and bovine leukemia virus (BLV) infections was conducted in four different cattle herds in Turkey. A total of 300 blood samples were analyzed and 12.3% were found to be positive for anti-BIV p26 antibodies by Western blot analysis and 1.6% positive for anti-BLV gp51 antibodies by an immunodiffusion test. BIV infection was confirmed with the detection of BIV-provirus DNA using the nested polymerase chain reaction. This is the first evidence for the presence of BIV in cattle in Turkey.  相似文献   
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Serological survey of bovine immunodeficiency virus (BIV) and bovine leukemia virus (BLV) infection was conducted in dairy cattle from 10 different regions of Hokkaido, Japan. Among 390 cattle, 11.0% of cattle were BIV-seropositive and 3.3% were BLV-seropositive. Moreover, in two dairy farms, where bovine leukosis has been reported, prevalence of BIV infections were 6.4 and 9.1%, respectively. In contrast, among 150 beef cattle, 16.6% were BIV-seropositive while none was BLV-seropositive. Dual infections with BLV and BIV in dairy cattle were tested by using 107 BLV-seropositive sera, and 20 sera were found BIV-positive (18.7%). These results indicate that BIV infection was widespread in Hokkaido.  相似文献   
44.
Fisheries Science - Morphological deformities of the jaw and vertebrae arise as hindrances to seed production of Japanese eel Anguilla japonica. To obtain basic information related to development...  相似文献   
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Theileria sergenti piroplasms were purified from different parasitemia peaks of cattle infected with parasitized erythrocytes or sporozoites during persistent infection. Their activities with monoclonal antibodies 13F5 and C9, which recognize 23 kDa and 32 kDa piroplasm surface proteins, respectively, were analyzed. Antigenic differences were observed among parasites from different parasitemia peaks during persistent infection when cattle were infected with sporozoites. Results of two-dimensional polyacrylamide gel electrophoresis showed that the 23 and 32 kDa proteins were expressed in all samples tested, regardless of their reactivities with the monoclonal antobodies. In contrast, parasites obtained from cattle inoculated with parasitized erythrocytes showed no antigenic alteration over a 2 month observation period. The results suggest that antigenic alteration of T. sergenti during persistent infection is related to whether the parasites proliferate through extraerythorocytic schizont stage in cattle or sporozoite and other sexual stages in tick vector.  相似文献   
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A novel thrombin inhibitory protein coding gene was identified from a cDNA library derived from salivary gland of partially-fed Haemaphysalis longicornis (hard tick). The gene encoded a 93-amino acid protein, designated chimadanin, which had a signal peptide sequence and was predicted to be a secretory protein. It showed no similarity to any other previously identified proteins or conserved domain sequences. The gene was expressed during blood feeding and suggested to be expressed mainly in the salivary gland. The predicted mature region of chimadanin was expressed in Escherichia coli and characteristics of the recombinant chimadanin were determined. The activated partial thromboplastin time and the prothrombin time in sheep plasma were significantly prolonged by chimadanin in a dose dependent manner. Amidolytic activity of thrombin was also inhibited by chimadanin in a dose dependent manner and it suggested that chimadanin was an anticoagulant with thrombin inhibitory activity. This newly identified thrombin inhibitor may play an important role in tick blood feeding.  相似文献   
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Myanmar native horses are small horses used mainly for drafting carts or carriages in rural areas and packing loads in mountainy areas. In the present study, we investigated genotype distributions and allele frequencies of the LCORL/NCAPG, MSTN and DMRT3 genes, which are associated with body composition and locomotion traits of horses, in seven local populations of Myanmar native horses. The genotyping result of LCORL/NCAPG showed that allele frequencies of C allele associated with higher withers height ranged from 0.08 to 0.27, and 0.13 in average. For MSTN, allele frequencies of C allele associated with higher proportion of Type 2B muscular fiber ranged from 0.05 to 0.23, and 0.09 in average. For DMRT3, allele frequencies of A allele associated with ambling gait ranged from 0 to 0.04, and 0.01 in average. The presences of the minor alleles of these genes at low frequencies suggest a possibility that these horse populations have not been under strong selection pressure for particular locomotion traits and body composition. Our findings of the presence of these minor alleles in Southeast Asian native horses are also informative for considering the origins of these minor alleles associated with body composition and locomotion traits in horse populations.  相似文献   
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In order to characterize the T helper 1 (Th1) cytokines of llama, we have cloned several llama cytokine genes and compared them to those of other mammalian species. The cDNAs encoding for interleukin (IL)-2, interferon (IFN)gamma, IL-12p35 and IL-12p40 were amplified using specific primers designed from reported sequences of bovine cytokine genes. The cDNAs for llama IL-2, IFN-gamma, IL-12 p35 and IL-12p40 were found to be 465, 501, 669 or 993 bp in length, with open reading frames encoding 154, 166, 222 or 330 amino acids, respectively. Homology analyses of nucleotide and deduced amino sequences of llama IL-2, IFN-gamma, IL-12p35 and IL-12p40 and phylogenetic analysis based on their nucleotide sequences indicated the close relationship in these cytokine genes between llama and eutherian mammalian order Artiodactyla, which includes pig and cattle.  相似文献   
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Bovine gut chitinase is exclusively produced in the liver and secreted into the blood. In the present study, we established a semi-quantitative method by Western blot analysis for measurement of the chitinase content in blood and examined its alteration during postnatal development and experimental infection with hemoprotozoan parasite in cattle. Its serum levels from 1 week to 1 year of age showed a significant increase only in 3-4-month-old group. The plasma concentration of the gut chitinase was not changed during acute inflammation caused by lipopolysaccharide but increased gradually after a Theileria injection and peaked at 52 days post-infection. It appears that the increase in the blood chitinase levels might be a defensive response in cattle against protozoan infection.  相似文献   
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