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Studies on effects of lactose on experimental Trypanosoma vivax infection in Zebu cattle. 2. Packed cell volume Полный текст
2008
Fatihu, M.Y.(Ahmadu Bello University Department of Veterinary Pathology and Microbiology) | Adamu, S.(Ahmadu Bello University Department of Biochemistry) | Umar, I.A.(Ahmadu Bello University Department of Biochemistry) | Ibrahim, N.D.G.(Ahmadu Bello University Department of Veterinary Pathology and Microbiology) | Eduvie, L.O.(Ahmadu Bello University National Animal Production Research Institute) | Esievo, K.A.N.(Ahmadu Bello University Department of Veterinary Pathology and Microbiology)
The ability of intravenously administered lactose in normal saline to prevent a decline in packed cell volume (PCV) during experimental trypanosomosis was studied in Zebu cattle. During the lactose infusion period, the PCV was stable up to Day 5 post-infection (p.i.) in a lactose-infused group, compared to that in an uninfused group in which the PCV dropped significantly (P < 0.05) as shown by the values of cumulative percentage change. Furthermore the mean rate of change in PCV was significantly (P < 0.05) higher in the uninfused group relative to the lactose-infused group during the same period. While the PCV fell markedly in the lactose-infused group a day after lactose infusion was stopped (Day 13 p.i.), subsequent PCV values were significantly (P < 0.05) higher compared to those in the uninfused group, up to the end of experiment on Day 17 p.i. However the mean rates of change in PCV did not vary significantly (P > 0.05) between the groups during the period in which lactose infusion was stopped. The mean levels of parasitaemic waves and parasitaemia were higher, more prolonged and more frequent in the lactose-infused group. It was inferred that the lactose was able to prevent an early onset of anaemia in the Trypanosoma vivax-infected Zebu cattle.
Показать больше [+] Меньше [-]Cardiotoxic effects of pavetamine extracted from Pavetta harborii in the rat Полный текст
2008
Hay, L.(University of Limpopo Department of Physiology) | Schultz, R.A.(Onderstepoort Veterinary Institute Section of Toxicology) | Schutte, P.J.(University of Limpopo Department of Physiology)
Previous studies have shown that crude extracts from Pavetta harborii as well as dried plant material have cardiotoxic effects on rats and sheep that can lead to heart failure. The active component has since been isolated and identified. This substance has been named pavetamine. The aim of this study was to determine whether pavetamine has cardiotoxic effects similar to those seen in previous reports, when administered to rats intraperitoneally. Sprague Dawley rats received two doses, initially 4 mg/kg and then 3 mg/kg pavetamine respectively and were monitored for 35 days before cardiodynamic parameters were measured by inserting a fluid-filled catheter into the left ventricle via the right carotid artery. These values were compared to those of control rats that had received only saline. Pavetamine significantly reduced systolic function and body mass in the treated rats, which indicates that it has the potential to induce heart failure in this animal model.
Показать больше [+] Меньше [-]Value of tests for evaluating udder health in dairy goats: Somatic cell counts, California Milk Cell Test and electrical conductivity Полный текст
2008
Petzer, I.M.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Donkin, E.F.(University of Pretoria Faculty of Natural and Agricultural Sciences Department of Animal and Wildlife Sciences) | Du Preez, E.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Karzis, J.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Van der Schans, T.J.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Watermeyer, J.C.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | van Reenen, R.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies)
The value of electric conductivity (EC), California Milk Cell Test (CMCT) and somatic cell count (SCC) as diagnostic tools was investigated in dairy goats. Conductivity colour reading correlated with SCC. Milk samples with conductivity colour red had significantly higher SCC than those with conductivity colours green and orange (P < 0.001). There were moderate positive correlations between CMCT (R² = 0.470), and conductivity score and CMCT and conductivity colour readings (R² = 0.597). Conductivity scores were significantly (P < 0.001) higher during and after intra-mammary treatment with Cloxamast LC and conductivity colours were significantly different between treatment and control groups (P < 0.001). There was a weak positive correlation between conductivity colour and stage of lactation (R² = 0.317) and a moderately positive correlation between conductivity score and stage of lactation (R² = 0.523). A moderately negative correlation was shown between milk yield and conductivity score (R² = -0.426) and between milk yield and conductivity colour (R² = -0.433). Moderate positive correlations were present between CMCT and SCC (R² = 0.689) and between CMCT and stage of lactation (R² = 0.459). CMCT ratings were significantly different (P < 0.001) for the intra-mammary treatment groups. CMCT ratings for infected and non-infected udder halves (P = 0.008) were significantly different; as were those for infected and non-infected udder halves and for left and right udder halves separately (P = 0.010). CMCT ratings for milk samples with SCC above and below 750 x 10³ cells per ml were significantly different (P < 0.001) as well as for milk from treated and control udder halves with SCC below or above 750 x 10³ cells per ml(P < 0.001). CMCT was found to be more accurate for indicating the absence of mastitis than for diagnosing it. There were significant differences in log SCC between treatment and control groups, during and after treatment. Infected udder halves had significantly higher log SCC than non-infected udder halves before and after treatment, but not during treatment. There was a moderate positive correlation between stage of lactation and SCC (R² = 0.438).
Показать больше [+] Меньше [-]Effect of Peganum harmala (wild rue) extract on experimental ovine malignant theileriosis: Pathological and parasitological findings Полный текст
2008
Derakhshanfar, A.(Shahid Bahonar University of Kerman School of Veterinary Medicine Department of Pathobiology) | Mirzaei, M.(Shahid Bahonar University of Kerman School of Veterinary Medicine Department of Pathobiology)
Malignant theileriosis of sheep is a highly fatal, acute or subacute disease is caused by the tick-borne protozoan parasite, Theileria hirci. In this investigation ten healthy male lambs aged 5-6 months were randomly divided into two groups, A and B and were kept in isolated tick-proof pens. They were treated for internal and external parasite before commencement of the experiment. The lambs were experimentally infected with T. hirci by placing ticks Hyalomma anatolicum anatolicum infected with T. hirci on them. The ticks used in this survey had originally been isolated from sheep and colonies of them were established in an insectarium. Before and after infection rectal temperatures and clinical signs of the lambs were recorded, blood and prescapular lymph node smears were prepared and examined to determine the extent of the parasitaemia, and blood samples were analyzed to evaluate their haemoglobin (Hb) and packed cell volume (PCV) rates. Three days after the commencement of a febrile reaction and appearance of the schizonts in the lymph node smears, treatment of the lambs in Group A with an extract containing the alkaloids of Peganum harmala (wild rue) was commenced. Group B lambs were kept untreated controls. Before treatment there were no significant differences in the rectal temperature, parasitaemia rate, and the Hb and PCV values between animals in the two groups but after treatment significant differences in these values was detected (P < 0.05). After treatment, the clinical signs and parasites in the lymph node smears of the animals in Group A disappeared and they all animals recovered. These parameters in the animals of Group B progressed until their death. Pathological studies showed the characteristic lesions of theileriosis in lambs in Group B, but not in Group A. The results indicate a therapeutic effect of the alkaloids of P. harmala for treatment of ovine malignant theileriosis.
Показать больше [+] Меньше [-]Development of vaccine strains of H5 and H7 influenza viruses
2008
Soda, K.(Hokkaido Univ., Sapporo (Japan)) | Sakoda, Y. | Isoda, N. | Kajihara, M. | Haraguchi, Y. | Shibuya, H. | Yoshida, H. | Sasaki, T. | Sakamoto, R. | Saijo, K. | Hagiwara, J. | Kida, H.
To establish vaccine strains of H5 and H7 influenza viruses, A/duck/Hokkaido/Vac-1/04 (H5N1) [Vac-1/04 (H5N1)], A/duck/Hokhaido/Vac-3/07 (H5N1) [Vac-3/07 (H5N1)], and A/duck/Hokkaido/Vac-2/04 (H7N7) [Vac-2/04 (H7N7)] were generated from non-pathogenic avian influenza viruses isolated from migratory ducks. Vac-1/04 (H5N1) and Vac-3/07 (H5N1) were generated by genetic reassortment between H5N2 or H5N3 virus as an HA gene provider and H7N1 or H6N1 virus as an NA gene provider. Vac-2/04 (H7N7) was a genetic reassortant obtained using H7N7 and H9N2 viruses to give high growth character of the H9N2 virus in chicken embryonated eggs. The results of sequence analyses and experimental infections revealed that these H5N1 and H7N7 reassortant viruses were non-pathogenic in chickens and embryos, and had good growth potential in embryonated eggs. These viruses should be useful to develop vaccines against H5 and H7 highly pathogenic avian influenza viruses.
Показать больше [+] Меньше [-]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.
Показать больше [+] Меньше [-]A BOLD-fMRI study of cerebra activation induced by injection of algesic chemical substances into the anesthetized rat forepaw
2008
Asanuma, T.(Hokkaido Univ., Sapporo (Japan)) | Yasui, H. | Sato, M. | Inanami, O. | Kuwabara, M.
This study was performed to examine whether the brain activities induced by noxious algesic chemical substances in anesthetized animals could be detected by blood oxygen-level-dependent functional magnetic resonance imaging (BOLD-fMRI). Multislice gradient echo images of the primary somatosensory cortex were obtained using a 7.05 T superconducting system and a one-turned surface coil centered over the primary somatosensory cortex of the 1.0%-isoflurane-anesthetized rat. The Z-score t-map of BOLD signals and its time-course analysis revealed that subcutaneous injection of formalin into the left forepaw immediately induced an early response in the contralateral primary sensory cortex lasting for a few minutes, followed by a late response until 20 min after stimulation. In contrast, injection of capsaicin into the left forepaw evoked only the early response. Furthermore, pretreatment with morphine completely abolished these responses induced by the chemical algesic substances. Thus BOLD-fMRI is a useful method to analyze the brain activities of painful stimulation in anesthetized animals.
Показать больше [+] Меньше [-]Downregulation of male-specific cytochrome P450 by profenofos
2008
Moustafa, G.G.(Hokkaido Univ., Sapporo (Japan)) | Ibrahim, Z.S. | Ahmed, M.M. | Ghoneim, M.H. | Sakamoto, K.Q. | Ishizuka, M. | Fujita, S.
The health hazards of individual organophosphorus insecticides have been characterized by their acute toxicity, mainly by investigating their cholinesterase inhibition. However, the chronic effects of most of these toxicants on the drug-metabolizing enzymes have not been investigated. Profenofos (O-4-bromo-2-chlorophenyl O-ethyl S-propyl phosphorothioate) is an organophosphorus pesticide widely used in cotton cultivation. In the present study, we investigated the effect of profenofos on male-specific cytochrome P450 (CYP) enzymes in adult Wistar rats. We orally administered 17.8 mg/kg body weight, twice weekly for 65 days. Profenofos downregulated levels of hepatic and testicular CYP2C11 and CYP3A2 mRNA and protein expression. Testicular aromatase (CYP19A) mRNA was decreased in the profenofos-treated rats compared to controls. Overall, the present study suggests that profenofos acts as an endocrine disruptor of male-specific CYP enzymes and affects testosterone concentration, which implicates its deleterious effects on animal or human males chronically exposed to organophosphorus pesticide.
Показать больше [+] Меньше [-]Protection by Nigella sativa against carbon tetrachloride-induced downregulation of hepatic cytochrome p450 isozymes in rats
2008
Ibrahim, Z.S.(Hokkaido Univ., Sapporo (Japan)) | Ishizuka, M. | Soliman, M. | ElBohi, K. | Sobhy, W. | Muzandu, K. | Elkattawy, A.M. | Sakamoto, K.Q. | Fujita, S.
Nigella sativa (family Ranunculaceae ) is an annual plant that has been traditionally used on the Indian subcontinent and in Middle Eastern countries. In this study, we investigated the effect of N. sativa oil on the drug-metabolizing cytochrome P450 (CYP) enzymes and whether it has a protective effect against the acute hepatotoxicity of CCl4. Intraperitoneal injection of rats with CCl4 drastically decreased CYP2E1, CYP2B, CYP3A2, CYP2C11, and CYP1A2 mRNA and protein expressions. Oral administration of 1 ml/kg N. sativa oil every day for one week prior to CCl4 injection alleviated CCl4-induced suppression of CYP2B, CYP3A2, CYP2C11, and CYP1A2. Moreover, CCl4 increased iNOS and TNFalpha mRNA, while N. sativa oil administration for one week prior to CCl4 injection downregulated the CCl4-induced iNOS mRNA and up-regulated IL-10 mRNA. These results indicate that N. sativa oil administration has a protective effect against the CCl4-mediated suppression of hepatic CYPs and that this protective effect is partly due to the downregulation of NO production and up-regulation of the anti-inflamnatory IL-10.
Показать больше [+] Меньше [-]Genetic and antigenic analyses of a Puumala virus isolate as a potential vaccine strain
2008
Daud, N.H.A.(Hokkaido Univ., Sapporo (Japan)) | Kariwa, H. | Tkachenko, E. | Dzagurnova. T. | Medvedkina, O. | Tkachenko, P. | Ishizuka, M. | Seto, T. | Miyashita, D. | Sanada, T. | Nakauchi, M. | Yoshii, K. | Maeda, A. | Yoshimatsu, K. | Arikawa, J. | Takashima, I.
Puumala virus (PUUV), a causative agent of hemorrhagic fever with renal syndrome (HFRS), is prevalent in Europe and European Russia. No vaccine has been developed for PUUV-associated HFRS, primarily because of the low viral yield in cultured cells. A PUUV strain known as DTK/Ufa-97 was isolated in Russia and adapted for growth in Vero E6 cells maintained in serum-free medium. The DTK/Ufa-97 strain produced a higher viral titer in serum-free medium, suggesting that it may prove useful in the development of an HFRS vaccine. When PUUV-infected Vero E6 cells were grown in serum-free medium, the DTK/Ufa-97 strain yielded more copies of intracellular viral RNA and a higher viral titer in the culture fluid than did the Sotkamo strain. Phylogenetic analysis revealed that PUUVs can be classified into multiple lineages according to geographical origin, and that the DTK/Ufa-97 strain is a member of the Bashkiria-Saratov lineage. The deduced amino acid sequences of the small, medium, and large segments of the DTK/Ufa-97 strain were 99.2% to 100%, 99.3% to 99.8%, and 99.8% identical, respectively, to those of the Bashkirian PUUV strains and 96.9%, 92.6%, and 97.4% identical, respectively, to those of the Sotkamo strain, indicating that the PUUVs are genetically diverse. However, DTK/Ufa-97 and other strains of PUUV exhibited similar patterns of binding to a panel of monoclonal antibodies against Hantaan virus. In addition, diluted antisera (i.e., ranging from 1:160 to 1:640) specific to three strains of PUUV neutralized both homologous and heterologous viruses. These results suggest that the DTK/Ufa-97 strain is capable of extensive growth and is antigenically similar to genetically distant strains of PUUV.
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