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A potential krimpsiekte vaccine Полный текст
2007
C.J. Botha | J.E. Crafford | V.P. Butler Jr. | M.N. Stojanovic | L. Labuschagne
A potential krimpsiekte vaccine Полный текст
2007
C.J. Botha | J.E. Crafford | V.P. Butler Jr. | M.N. Stojanovic | L. Labuschagne
Krimpsiekte, a chronic form of cardiac glycoside poisoning, is an important plant-induced intoxication of small stock in South Africa. It is caused by cumulative, neurotoxic bufadienolides, such as cotyledoside. A cotyledoside-bovine serum albumin conjugate was synthesized to immunize animals. The efficacy of the cotyledoside-conjugate in inducing an immunological response was ascertained in rabbits (n = 4) and sheep (n = 4) by determining cotyledoside antibody titres with an ELISA using cotyledoside-hen ovalbumin as antigen. The formation of anticotyledoside antibodies was induced in both rabbits and sheep following immunization with the cotyledoside-protein conjugate. Protection provided by the vaccine was demonstrated by challenging sheep (n = 4) with repeated, daily doses of cotyledoside (0.015 mg / kg) administered intravenously, commencing 45 days after the initial vaccination. One control animal died on Day 3 of the challenge period and the other was severely affected after administration of the third cotyledoside dose. The immunized ewes (n = 2) remained clinically unaffected and the challenge was suspended following six daily injections. Vaccination as a means of preventing krimpsiekte seems to be quite feasible and deserves further investigation.
Показать больше [+] Меньше [-]Evaluation of Lactobacilli and active dry yeast in the prevention and control of quail colibacillosis Полный текст
2007
A. S. E. D. Metwali | Jihan M. Badr | Amal I. Yoseif
Two experiments were carried out to evaluate the efficacy of the administration of active dry yeast and/or lactobacillus preparation (AVI-BAC), either before or after the infection with antibiotic resistant field strain of Escherichia coli O127 (E. coli O127) in controlling the severity of infection in quail chicks. The quail chicks of the different experimental groups were infected orally for two successive days with 3x107 CFU of E. coli O-127 as an individual dose. The used field strain proved to be highly pathogenic for quails. Probiotics were supplemented in the drinking water for the different treatment groups at a dose level of 0.5 gm/L. The results revealed that the inclusion of lactobacilli or active dry yeast before E. coli infection has been highly effective in reducing mortality rate, organ invasion and the number of E. coli positive quail chicks. In addition, it decreased the severity of macroscopic and microscopic lesions in different organs in the probiotic treated groups as compared to the infected controls. Lactobacilli preparations were more efficient in controlling the severity of the infection. On the other hand, the administration of yeast and /or lactobacilli after inducing E. coli infection reduced the mortality rate and the severity of lesion score in different organs but probiotics failed to protect quail chicks against the infection. It has been proved that the two probiotics have synergistic effect in controlling collibacillosis in quails.
Показать больше [+] Меньше [-]Some helminthes of the Great Egret (Egretta alba) in Saudi Arabia Полный текст
2007
A. N. Al Khalaf
A. N. Al Khalaf helminthes , Egret , Egretta alba , Saudi ArabiaExamination of the alimentary tracts of 9 Great Egret (Egretta alba) found freshly died in their inland places around Al-Qassim area during migration season in September and October revealed infection by 6 species of helminths. The extracted parasites were include two cestode worms, three nematodes and one acanthocephala. They were identified as Uniciuna species, Choano-taenia, Subulura species, Contrac-aecum species, Syphacia species and Polymorphus species. None of any examined carcass appears free from infection. The rate of distribution of the parasite in the examined birds was varied between 66.6%, 11.1%, 44.4%, 44.4%, 66.6% and 2.2 % for the previous parasites respectively. The rate of Parasite burden for each species was moderate to low, as it was 3.4, 2.0, 2.65, 3.25, 5.16 and 4.5 from the previous parasites respectively. None of these parasites was published previously in Saudi Arabia as infect this type of Egret. Their morphological characters and their distribution were described in detail
Показать больше [+] Меньше [-]Prevalence and determinants of <i>Cryptosporidium</i> spp. infection in smallholder dairy cattle in Iringa and Tanga Regions of Tanzania Полный текст
2007
E.S. Swai | N.P. French | E.D. Karimuribo | J.L. Fitzpatrick | M.J. Bryant | D.M. Kambarage | N.H. Ogden
The prevalence of Cryptosporidium spp. infection in a cross-sectional study of dairy cattle, from two contrasting dairying regions in Tanzania, were determined by staining smears of faecal samples with the modified Ziehl-Neelsen technique. Of the 1 126 faecal samples screened, 19.7% were positive for Cryptosporidium spp. The prevalence was lower in Tanga Region than in Iringa Region. The prevalence of affected farms was 20% in Tanga and 21% in Iringa. In both regions, the probability of detecting Cryptosporidium oocysts in faeces varied with animal class, but these were not consistent in both regions. In Tanga Region, Cryptosporidium oocysts were significantly more likely to be found in the faeces of milking cows. In Iringa Region, the likelihood that cattle had Cryptosporidium-positive faeces declined with age, and milking cattle were significantly less likely to have Cryptosporidium positive faeces. In this region, 7% of cattle were housed within the family house at night, and this was marginally associated with a higher likelihood that animals had Cryptosporidium-positive faeces. Our study suggests that even though herd sizes are small, Cryptosporidium spp. are endemic on many Tanzanian smallholder dairy farms. These protozoa may impact on animal health and production, but also on human health, given the close associations between the cattle and their keepers. Further studies are required to assess these risks in more detail, and understand the epidemiology of Cryptosporidium spp. in this management system.
Показать больше [+] Меньше [-]Helminths of guineafowls in Limpopo Province, South Africa Полный текст
2007
K. Junker | J. Boomker
Helminths of guineafowls in Limpopo Province, South Africa Полный текст
2007
K. Junker | J. Boomker
Between July 2005 and November 2006 the gastro-intestinal helminths of 15 Helmeted guineafowls and a single Crested guineafowl from Musina, Limpopo Province were examined, and in July and August 2005 helminths were collected from five Helmeted guineafowls from Mokopane in the same province. The acanthocephalan Mediorhynchus gallinarum, the cestodes Abuladzugnia gutterae, Davainea nana, Hymenolepis cantaniana, Numidella numida, Octopetalum numida, Ortleppolepis multiuncinata, Porogynia paronai, Raillietina angusta, Raillietina pintneri, Raillietina steinhardti and Raillietina sp. and the nematodes Ascaridia numidae, Cyrnea parroti, Gongylonema congolense, Hadjelia truncata, Sicarius caudatus, Subulura dentigera, Subulura suctoria, Subulura sp., Tetrameres numida and an unidentified subulurid were recovered. A single trematode species, Dicrocoelium macrostomum, was present in the liver. Mediorhynchus gallinarum, A. gutterae, O. multiuncinata, H. truncata and S. caudatus are recorded for the first time from Helmeted guineafowls, as well as from South Africa. South Africa is a new geographic record for D. macrostomum, G. congolense and D. nana. Subulura suctoria, G. congolense and H. truncata from the Crested guineafowl constitute new host-parasite associations.
Показать больше [+] Меньше [-]Comparison of the survival on ice of thawed <i>Theileria parva</i> sporozoites of different stocks cryoprotected by glycerol or sucrose Полный текст
2007
V. Mbao | D. Berkvens | P. Dorny | P. Van Den Bossche | T. Marcotty
Stabilates of Theileria parva sporozoites are mostly delivered in liquid nitrogen tanks to the East Coast fever immunization points. Using an in vitro titration model, we assessed the loss of infectivity of several stabilates when they are stored in ice baths for up to 24 h. Comparisons, with respect to rates of loss of infectivity, were made between T. parva stocks (Chitongo and Katete), cryoprotectants (sucrose and glycerol) and method of assessment (in vivo and in vitro techniques). Chitongo and Katete stabilates showed similar loss dynamics. The losses were 1-4 % (depending on parasite stock) and 3 % per hour of storage for glycerol and sucrose stabilates respectively, and the loss rates were not significantly different. The results suggest that Chitongo stabilates and sucrose cryoprotected suspensions can be delivered on ice as is done for Katete. A graphical relationship of in vitro effective dose at 50 % infectivity (ED50) and in vivo protection rate was made. The relationship showed a 35 % loss of protection for a relatively low corresponding increase of ED50 from 0.006 to 0.007 tick equivalent.
Показать больше [+] Меньше [-]Effect of high water temperature on natural resistance of cultured Oreochromis niloticus Полный текст
2007
M. N. M. Ali
Killing activity of fresh Oreochromis niloticus serum was used as an indicator of the natural immunity. Serum killing activity was tested in temperature stressed fish exposed to 32 ±1°C to different Pseudomonas fluorescens strains. As a clinical estimate of natural immunity and disease resistance, experimental challenge with P. fluorescens strains was conducted. The results cleared that serum killing activity at 32±1°C was almost stopped where fish got infected after bacterial challenge. On the other hand, control fish group kept at 23± 1°C developed serum killing activity and resistance to the acquisition of infection after challenge. A correlation was found between resistance activities of P. fluorescens strains to serum killing and their corresponding courses of infection after bacterial challenge. However, the results of experimental challenge conducted at 32±1°C suggested that the immunocompromising state resulted from the stress of inability to withstand high water temperature is exclusively the critical aspect for the induction of infection.
Показать больше [+] Меньше [-]Anti-inflammatory, antipyretic and analgesic effect of Achillea millefolium and Salix plants Полный текст
2007
S. E. El-Sadek | A. A. M. El-Gendy | M.A. Tohamy | M. A. Abd El-Aa
The Anti-inflammatory, antipyretic and analgesic effect of Achillea millefolium and Salix were investigated in rats and mice. The extracts of Achillea millefolium exerted significant antiinflammatory, antipyretic and analgesic effects. Also potentiated the sleeping time of thiopental sodium in mice. The doses used were 10.375 and 20.75 (watery extract) and 9.5 and 19 mg/100 gm b.wt. (ethanolic extract). Salix produced the same effects at doses of 0.0825 and 0.165 (watery extract) and 0.0850 and 0.170 mg/100 gm b.wt. (ethanolic extract). The extracts of both plants have an anti-inflammatory, antipyretic and analgesic effect
Показать больше [+] Меньше [-]Preliminary application and evaluation of loop-mediated isothermal amplification (LAMP) for detection of bovine theileriosis and trypanosomosis in Tanzania : research communication Полный текст
2007
O.M.M. Thekisoe | J.D. Omolo | E.S. Swai | K. Hayashida | J. Zhang | C. Sugimoto | N. Inoue
The sensitivity of LAMP, PCR and microscopy to detect Theileria spp. and Trypanosoma congolense in field-derived bovine blood samples from Tanzania was evaluated and compared. No parasites were detected by microscopy. Furthermore, no bovine Theileria spp. were detected by LAMP and PCR from all the 24 samples collected from Arusha. Four and one out of 24 samples were positive for Theileria congolense infection by LAMP and PCR respectively while, 18 and nine out of 40 samples from Dar es Salaam were positive by LAMP and PCR for Theileria spp. Infection, respectively. Although all samples from Dar es Salaam were negative for Trypanosoma congolense infections by PCR, 12 out of 40 samples were LAMP positive. Whilst PCR is an established gene amplification method for the detection of Theileria and trypanosome parasites, this study introduces LAMP as an alternative molecular diagnostic tool that could be used in large-scale epidemiological surveys.
Показать больше [+] Меньше [-]Study of the genetic heterogeneity of SAT-2 foot-and-mouth disease virus in sub-Saharan Africa with specific focus on East Africa Полный текст
2007
M. Sahle | R.M. Dwarka | E.H. Venter | W. Vosloo
Study of the genetic heterogeneity of SAT-2 foot-and-mouth disease virus in sub-Saharan Africa with specific focus on East Africa Полный текст
2007
M. Sahle | R.M. Dwarka | E.H. Venter | W. Vosloo
The epidemiology of serotype SAT-2 foot-and-mouth disease was investigated in sub-Saharan Africa by phylogenetic analysis using the 1D gene encoding the major antigenic determinant. Fourteen genotypes were identified of which three are novel and belong to East Africa, bringing the total number of genotypes for that region to eight. The genotypes clustered into three lineages that demonstrated surprising links between East, southern and south-western Africa. One lineage was unique to West Africa. These results established numerous incursions across country borders in East Africa and long term conservation of sequences for periods up to 41 years. Ethiopia, Kenya and Uganda have all experienced outbreaks from more than one unrelated strain, demonstrating the potential for new introductions. The amount of variation observed within this serotype nearly equalled that which was found between serotypes; this has severe implications for disease control using vaccination.
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