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Small mammals as hosts of immature ixodid ticks 全文
2005
I.G. Horak | L.J. Fourie | L.E.O. Braack
Two hundred and twenty-five small mammals belonging to 16 species were examined for ticks in Free State, Mpumalanga and Limpopo Provinces, South Africa, and 18 ixodid tick species, of which two could only be identified to genus level, were recovered. Scrub hares, Lepus saxatilis, and Cape hares, Lepus capensis, harboured the largest number of tick species. In Free State Province Namaqua rock mice, Aethomys namaquensis, and four-striped grass mice, Rhabdomys pumilio, were good hosts of the immature stages of Haemaphysalis leachi and Rhipicephalus gertrudae, while in Mpumalanga and Limpopo Provinces red veld rats, Aethomys chrysophilus, Namaqua rock mice and Natal multimammate mice, Mastomys natalensis were good hosts of H. leachi and Rhipicephalus simus. Haemaphysalis leachi was the only tick recovered from animals in all three provinces.
显示更多 [+] 显示较少 [-]Clinicopathological studies on experimentally infected rabbits with bovine herpesvirus -1 全文
2005
Walaa M. Sayed | H. H. Kamel | Azza H. Abd-El-Rahman | K. A. El-Nesr | H. M. Madbouly | Amira H. Mohamed
Forty-eight pathogen free New Zealand rabbits were divided into two groups, the first group contained eighteen rabbits served as normal control and the second group of thirty rabbits were received 1 ml bovine herpesvirus-1 (BHV-1) virus suspension (107 TCID 50) by intraperitoneal route. Rabbits both groups were subjected to hematological, serum biochemical, different serological and histopathological examination 3,7,10,14,21 and 28 days post infection. Clinical observation of infected rabbits showed febrile response and mild conjunctivitis after 24 and 48h. of inoculation, respectively. The hemogram revealed no significant alteration in the erythrogram while leucogram showed leucocytosis accompanied with heterophilia, lymphopenia and monocytopenia at the 3rd and 7th days post infection. Serum biochemical analysis showed significant elevation in the activity of AST, ALT and AP and in blood urea nitrogen and creatinine concentration along the experimental period. Serum total proteins, albumin, :, ; and < globulin significantly increased at different periods of the experiment. BHV-1 antibodies were detected in the sera of infected rabbits by Dot ELISA and ELISA from the first week until the forth week post infection. Histopathological examination revealed that the most affected organs were the trachea, lungs and liver while adrenals, kidneys, and spleen showed mild pathological alterations.
显示更多 [+] 显示较少 [-]Efficacy of some diagnostic procedures used for diagnosis of Trypanosomiasis in camels 全文
2005
A. M. El-Sherif | A. Sayed
A total of 980 camels were employed in this study for evaluation of some diagnostic procedures used for diagnosis of camel trypanosomiasis. Clinical examination revealed that 180 (18.37%) camels showed sings of illness including, loss of body weight, anemia, abortion, decrease of animal production and edema in some parts of the body. Parasitological examination of camel’s blood smears revealed the presence of Trypanosoma evansi in 57 (5.82%) camels. ELISA detected 99 (63.06%) positive cases while suratex test identified 80 (50.96%) positive cases. Results of mice inoculation test for detection of Trypanosoma evansi among camels showed that 69 (43.95%) camels were positive. The present study clarified that suratex test was 100% sensitive for diagnosis of trypanosomiasis followed by ELISA (98.55%).
显示更多 [+] 显示较少 [-]Natural infection rates and transmission of <i>Theileria annulata</i> by <i>Hyalomma anatolicum anatolicum</i> ticks in the Sudan 全文
2005
D.A. Salih | O.E. Sharieff | A.G. Lazarus | S.M. Hassan | A.M. El Hussein
Hyalomma anatolicum anatolicum nymphs were collected from two localities in the Sudan: Eddamer in Northern Sudan and Wad-Medani in Central Sudan. They were allowed to moult to adult ticks, which were assessed for Theileria infection in their salivary glands using Feulgen stain. At Eddamer, 49.6 % of 123 ticks examined were infected with Theileria and the mean intensity of infection was 1.3 (i.e. the number of infected acini / number of infected ticks). At Wad-Medani, 8.6 % of 162 ticks were infected and the mean intensity of infection was 7.9. The prevalence of infection was higher in female than in male ticks at both localities. When adult H. a. anatolicum were applied onto two susceptible calves, both animals developed the severe form of theileriosis.
显示更多 [+] 显示较少 [-]The performance of Orma Boran and Maasai Zebu crossbreeds in a trypanosomosis endemic area of Nguruman, south western Kenya 全文
2005
M.W. Maichomo | J.M. Ndungu | P.M. Ngare | I.M. Ole-Mapenay
Studies on the trypanotolerance of Orma Boran X Maasai Zebu (Orma Zebu) crossbred cattle (F1 progeny) and pure-bred Maasai Zebu contemporaries were carried out in Nguruman, south western Kenya. The two groups were monitored from birth for a period of 2 years. The incidence of trypanosomosis, parasitaemia, packed cell volume (PCV), body mass and average daily mass gain were monitored. During the study period, overall trypanosomosis incidence was low (3 %). The crossbred cattle had a higher incidence of infection (61 % vs 39 %). The mean PCV and mean mass gain for the crossbred cattle was higher than that of the Maasai Zebu. The mean calf body mass at weaning (8 months) for the Orma Zebu and Maasai Zebu was 72 kg and 64 kg, respectively, while at 18 months of age their mean body mass was 164 kg and 123 kg, respectively. During the rainy season significant differences in average daily mass gains were noted (P < 0.05). The superior mass gain of the Orma Zebu observed during the rainy season, despite higher infection rates, indicate an enhanced trypanotolerance. Moreover, the better performance of the Orma Zebu is an attribute that could be exploited in the adoption of the trypanotolerance genotype, as a sustainable trypanosomosis control strategy.
显示更多 [+] 显示较少 [-]Effect of intensity of fecal pat sampling on estimates of Escherichia coli O157 prevalence 全文
2005
Echeverry, A. | Loneragan, G.H. | Wagner, B.A. | Brashears, M.M.
To evaluate site-to-site variation within fecal pats from cattle with regard to detection of Escherichia coli O157 and determine the effect on the accuracy of prevalence estimates of assay of multiple samples collected from the same fecal pat. 120 freshly voided fecal pats collected from 2 beef feedlots. Procedures-5 samples were systematically collected from each fecal pat and analyzed for E coli O157 via selective preenrichment techniques, immunomagnetic separation, and biochemical tests. Presumptive isolates were definitively identified via agglutination assays and polymerase chain reaction techniques. Best estimators of prevalence were calculated from the distribution of E coli O157-positive samples per pat. Of the 120 fecal pats, 96, 13, 4, 2, 3, and 2 fecal pats had 0, 1, 2, 3, 4, and 5 E coli O157-positive samples, respectively. The greatest estimate of E coli O157 prevalence (20%) was achieved when all 5 samples were assessed; this estimate represented a 2.4- fold increase in prevalence, compared with that provided via analysis of 1 sample/pat (8.2%). Compared with assessment of 5 sites/pat, the relative sensitivity of detecting an E coli O157-positive fecal pat via analysis of 1 site/pat was 40.1%. Results suggest that estimates of E coli O157 prevalence derived from sampling of 1 location/pat are likely underestimates of the true prevalence of this pathogen in fecal pats (and by extension, cattle). Additional research is warranted to confirm these results in situations of high and low prevalence and across different feedlots.
显示更多 [+] 显示较少 [-]Detection of the meq gene in the T cell subsets from chickens infected with Marek's disease virus serotype 1
2005
Chang, K.S.(Hokkaido Univ., Sapporo (Japan)) | Ohashi, K. | Lee, S.I. | Takagi, M. | Onuma, M.
The meq gene was thought to be only detected in Marek's disease virus serotype 1 (MDV1) including a very virulent strain, Md5, while L-meq, in which a 180-bp sequence is inserted into the meq open reading frame, is found in other strains of MDV1, such as CVI988/R6. However, both meq and L-meq were previously detected by PCR in chickens infected with MDV1, suggesting hat MDV1 may consists of at least two subpopulations, one with meq, the other with L-meq. To further analyze these subpopulations, we analyzed the time course changes in distribution of these subpopulations among T cell subsets from chickens infected with MDV1. Both meq and L-meq were detected in CD4(+) and CD8(+) T cells infected with strain Md5 or CVI988/R6. The shift in MDV subpopulations from one displaying meq to the other displaying L-meq and/or the conversion from meq to L-meq occurred mainly in the CD8(+) T cell subset from Md5- infected chickens. PCR products corresponding to L-meq rather than meq were frequently amplified from the CD8(+) T cell subset from CVI988/R6-infected chickens. These results suggest that a dominant subpopulation of MDV1 changes depending on the T cell subsets, and that L-meq is dominantly present in the CD8(+) T cells which play a role in the clearance of pathogenic agents.
显示更多 [+] 显示较少 [-]Upregulation of renal renin-angiotensin system in mouse diabetic nephropathy
2005
Tamura, J.(Hokkaido Univ., Sapporo (Japan)) | Konno, A. | Hashimoto, Y. | Kon, Y.
The aim of this study was to clarify the role of the renal renin-angiotensin system (RAS) in diabetic nephropathy (DN) , which was induced by injection of streptozotocin (STZ). Male CBA/N and CBA/J mice were compared in this study. The former possesses a single renin gene, Ren1. whereas the latter carries two renin genes, Ren1 and Ren2. To examine the molecular dynamics of renal RAS, including renin, angiotensinogen (Agt), angiotensin-converting enzyme (Ace), angiotensin type 1 (Agtr1) and type 2 (Agtr2) receptors in experimental DN, we performed laser-microdissection (LMD) followed by reverse transcriptase nested polymerase chain reaction using each specific primer pairs and immunohistochemistry for renin and angiotensin 2. CBA/N mice had a higher response after injection of STZ than CBA/J mice, showing a significant increase of the kidney/body weight ratio, although there was no significant difference between the two strains for the blood glucose level or pancreatic beta-cell response. The onset of renal pathological changes associated with DN was earlier and more severe in CBA/N mice than in CBA/J mice. Distinct immunoreactivities for renin and angiotensin 2 were newly distributed on the flattered epithelial cells in the dilated distal tubules in the cortex as well as the collecting ducts in the cortex and medulla, and were demonstrated more intensity in CBA/N mice than in CBA/J mice. Micro dissectional analysis in both models revealed a higher incidence of RAS-related gene expression in CBA/J, Ren 2 mice than in CBA-N, Ren 1 mice.
显示更多 [+] 显示较少 [-]Viral and bacterial diseases in livestock in Mongolia
2005
Odontsetseg, N. (Hokkaido Univ., Sapporo (Japan)) | Mweene, A.S. | Kida, H.
5371 This review focuses on the status of infectious diseases that are serious for animal health and have adverse economic effects in Mongolia. Data presented here are limited due to the lack of published or other easily available documents. Foot-and-mouth disease continues to cause substantial economic losses as exemplified by the outbreak of infection with serotype O PanAsia lineage virus. In the case of the 2001 outbreak, a 65%reduction in export revenues was recorded. In order to ascertain the free status of Mongolia from rinderpest, sero-epidemiological surveillance has been carried out since 2001. In 2004, Mongolia was certified free from rinderpest by Office Interna-tional des Epizooties (OIE). A sharp rise in both animal and human brucello-sis incidence has become a serious problem. Rabies and anthrax remain endemic with occasional human cases. Other prevailing infectious diseases are contagious pustular dermatitis, contagious agalactia, enterotoxemia and ¡pas-teurellosis. The current programs for the control of infectious diseases in livestock in Mongolia lack a definite policy that would enable rapid implementation. A large-scale surveillance of infectious diseases in animals and management of appropriate preventive measures are urgently required in Mongolia.
显示更多 [+] 显示较少 [-]Antigenotoxic effect of Pleurotus cornucopiae extracts on the mutagenesis of Salmonella typhimurium TA98 elicited by benzo(a)pyrene and oxidative DNA lesions in V79 hamster lung cells
2005
Bohi, K.M.E. (Hokkaido Univ., Sapporo (Japan)) | Sabik, L. | Muzandu, K. | Shaban, Z. | Soliman, M. | Ishizuka, M. | Kazusaka, A. | Fujita, S.
Pleurotus cornucopiae (PC) mushroom with a brilliant yellow pileus is found in the field and known in Japan as Tamogi dake mushroom. The purpose of this paper is to investigate the mechanism of the antimutagenic effect of PC mushroom using both the Ames test and Comet assay. We have found a strong inhibitory effect of both aqueous and organic PC extracts on the mutagenicity elicited by benzo[a]pyrene (B[a]P). This inhibition was dose- dependent in reaction mixtures containing cytosolic and microsomal fractions (S-9) from untreated rat liver as well as in those containing S-9 from aryl hydrocarbon receptor (Au) ligand of Sudan III-treated rats. Sudan III was a potent inducer of cytochrome P450 1A (CYP1A) activity. We treated rats with Sudan III to enhance the metabolic activation of B[a]P by the S-9 fraction. To explain whether this antimutagenicity was due to the inhibition of CYP1A activity that metabolically activates B[a]P, we tested the effects of the extracts on activities of CYP1A1 and CYP1A2, represented by ethoxyresorufin Odeethylase (EROD) and methoxyresorufin Odemethylase (MROD), respectively. Both aqueous and organic extracts inhibited EROD activity at all dose levels, while the inhibitory effect was only observed at high doses with regard to MROD activity. Furthermore, pre-treatment of Chinese hamster V79cells with PC extracts significantly reduced H2O2 - induced-DNA damage, indicating that PC extracts provide a protective effect against oxidative DNA damage. These results indicate that whole-mushroom extracts contain compounds that may inhibit the metabolic activation of B[a]P by CYP1A1 as well as prevent oxidative DNA damage.
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