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1.
A sero-epidemiological study of Taenia saginata cysticercosis was carried out in adult cattle in Zambia to determine the prevalence and study the influence of the farming system on the infection rate. Serum samples were examined for circulating parasite antigen by a monoclonal-based sandwich ELISA. Thirty-eight of 628 serum samples were found positive (prevalence 6.1%). Cysticercosis was significantly more prevalent in feedlots and in traditional farming systems than in dairy farms. It is suggested that the continuous man to animal contact and the use of casual workers in feedlots may be factors that are conductive to T. saginata transmission.  相似文献   

2.
The serum antibody levels to Taenia saginata of three groups of cattle were assessed by an enzyme-linked immunosorbent assay (ELISA). The first group of cattle were from four farms which had a confirmed T saginata cysticercosis outbreak, all of which had cattle classed as infected by ELISA. The second group were from four farms where sewage sludge had been applied to pasture subsequently grazed by the cattle. One of these farms had cattle classed as infected by ELISA. The control cattle, which were all classed as uninfected by ELISA, came from five farms whose pasture had not been treated with sewage sludge. In a wider survey, involving sera from 47 additional farms, the majority could not be distinguished from the control farms in the earlier survey. However, samples from three of the farms had a similar number of positives to two of the known infected farms in the initial survey. Since the ELISA assay may indicate infected herds, farms such as these warrant further investigation.  相似文献   

3.
Serum IgG response of cattle with cysticercosis caused by Taenia saginata was studied in an enzyme-linked immunosorbent assay (ELISA) where a T. saginata metacestode surface extract was used as antigen. In experimentally infected calves, a sharp rise in specific antibody levels was found 3-4 weeks after the infection followed by a logical level of detection corresponded to about 25 cysts. The ELISA was employed in cattle herds where cysticercosis outbreaks had occurred and also in supposedly uninfected herds. Significantly increased antibody levels were found in the herds with massive cysticercosis cases. The test was not adapted for individual diagnosis as some animals of the uninfected herds, especially within the older age groups, had elevated antibody values. The ELISA was, however, useful in the investigation of outbreaks to determine the extent and pattern of the infection in the herd. The rate of decline in antibody levels in these herds was studied by follow up sampling. The increased antibody levels in the infected herds were also reflected in colostrum-fed calves. This observation was employed to estimate the time of infection.  相似文献   

4.
The distribution of Taenia saginata cysts was recorded in 23 experimentally infected calves. The calves harboured between two and 2569 cysts. A median of 15.7 per cent of the cysts were located in the heart and 6.5 per cent in the masseter muscles, the organs usually considered as the most important predilection sites. From these findings a simple probability model was used to estimate the meat inspection sensitivity at different infection levels. It was concluded that the possibility of detecting infected cattle is limited especially when, as in Denmark, the majority of animals are lightly infected.  相似文献   

5.
Taenia saginata cysticercosis in an Ohio cattle feeding operation   总被引：1，自引：0，他引：1  
In January to March 1981, 37 slaughter cattle from a single Ohio feeding operation were determined, at postmortem inspection, to be infected with Taenia saginata cysticerci. A subsequent outbreak on this same farm in March 1983 involved 7 slaughter cattle. An epidemiologic investigation was conducted of possible sources of the T saginata ova; these included leakage of raw sewage onto the pasture after a flood in 1980, municipal sewage sludge application on the farm, defecation in feed or water by farm workers, and other off-farm sources. Temporal and spatial observations implicated raw sewage contamination of pastures as the most likely source of infection in the 1981 outbreak. The outbreak in 1983 was more likely associated with sludge application. The possibility of an infected worker exposing the cattle to infected feces was not excluded definitely as a possible source.  相似文献   

6.
Epidemiological studies were made on 14 farms from which, during a 2 year period, 38 cattle had been condemned at slaughter, due to massive infections with Cysticercus bovis. By on-site investigations and interviews, attempts were made to identify the transmission routes of Taenia saginata eggs from human faeces into the environment and further on to cattle. The most frequent sources of infection were found to be sludge from septic tanks illegally applied on pasture or crops, in some cases after having been mixed with animal slurry. Animals in permanently housed herds were infected through the fodder or by contamination of the indoor environment by such slurry containing Taenia eggs. Other herds were infected by grazing pastures in close proximity to municipal sewage treatment plants. In contrast to earlier Danish observations, application on farmland of sewage sludge from municipal treatment plants was not involved in any of the reported outbreaks. This apparent change coincides with the implementation of more restrictive legislation for the agricultural use of sewage sludge in Denmark.  相似文献   

7.
Bovine cysticercosis is an important food safety issue and can cause economic loss. A cross sectional study on Taenia saginata cysticercosis was carried out in slaughtered cattle in Iran in order to determine the infection rate during a three-years period, from 2005 to 2007. A total of 4,534,105 cattle were examined by routine meat inspection. The results showed that 11,410 cattle (0.25 %) were infected with Cysticercus bovis; among those 1,041 carcasses (0.02%) were condemned. In such carcasses the metacestodes caused extensive damage in the vicinity of cysts in infected cattle. The rejected carcasses had an average of 410 thousands USD loss annually.  相似文献   

8.
The occurrence of cysticercosis due to Taenia saginata in cattle slaughtered for meat in Amhara National Regional State, northwestern Ethiopia between September 2005 and February 2007 was investigated. Routine meat inspection of various organs of 4456 cattle in eight abattoirs of this region showed that 824 (18.49%) were infected with Cysticercus bovis. The occurrence rate did not vary significantly from abattoir to abattoir (P>0.5). The tongue, masseter muscles, heart muscles, triceps muscles and thigh muscles were the main predilection sites of the cysts. Of 4102 male cattle, examined, 768 (18.72%) had cysts of C. bovis while 56 (15.82%) of the 354 female animals investigated were infected. The animals slaughtered were all adults. No significant difference in occurrence was recorded between the sexes. Monthly occurrence of the cysts in the animals revealed a rise of infected animals during the dry season.  相似文献   

9.
In the present work, the species-specific identification of Taeniid spp. cysticerci and sarcocystis cysts isolated from infected pigs and cattle was achieved by PCR. In particular: (i) multiplex-PCR derived from HDP2 DNA fragment, specific for Taenia saginata/Taenia solium; (ii) PCRs and PCR-RFLPs of the rDNA internal transcribed spacers 1 and 2 (ITS1 and ITS2) for the differential diagnosis of taeniids; (iii) PCR derived from the 18S rRNA gene and sequencing, specific for Sarcoystis spp. The combined application of these three PCR protocols provided an unequivocally specific diagnosis of T. saginata, T. solium, T. hydatigena, Sarcocystis hominis and Sarcocystis suihominis, and may have practical application in the identification of calcified degenerating or morphologically dubious cysts, for example in the slaughter house situation or in human biopsy samples.  相似文献   

10.
A 'dipstick' immunoassay for bovine cysticercosis, using an antigen isolated from Taenia hydatigena cyst fluid, was evaluated in cattle experimentally infected with Taenia saginata. The assay correctly identified six out of seven infected cattle, including an animal in which only 12 living cysticerci were found. Cattle became seropositive as early as 3 weeks post-infection. A false-negative reaction was found for one very lightly infected animal, from which only four living cysticerci were recovered at necropsy. The assay was also used to detect circulating antibodies in experimentally infected cattle before and after therapeutic treatment with anthelminthics. The results suggest that praziquantel-treated animals gradually revert to being seronegative after the cysticerci are killed.  相似文献   

11.
Immunity in Taeniids is predominantly antibody mediated and thus many serological immuno-determinants will have potential in both protection and diagnosis. The antigenicity of six peptides derived from four potentially protective molecules cloned from a Taenia saginata oncospheres cDNA library have been evaluated as targets for the specific diagnosis of bovine cysticercosis. The six peptides consist of: two peptides (HP6-2 and HP6-3) derived from the sequence of the 18 kDa surface/secreted oncospheral adhesion antigen identified by McAb-HP6, two peptides (Ts45W-1 and Ts45W-5) derived from the sequence of the T. saginata homologue of the T. ovis 45W protective gene family, one peptide (TS45S-10) derived from a T. saginata sequence with significant similarity to the T. ovis 45S protective antigen, and one peptide (TEG-1) derived from the sequence of the T. saginata homologue of Echinococcus spp. main surface protein. Longitudinal studies indicate that T. saginata infected cattle respond to all six peptides by 3-4 weeks post-infection and that the antibody levels remain high for at least 12 weeks post-infection. As protection against Taeniid parasites is predominantly antibody mediated, some of these six peptides may be of value as immuno-prophylactic tools and hence also in assays to determine resistance to infection with the parasite. For diagnosis, on the other hand, only three peptides (HP6-2, TEG-1 and Ts45S-10) performed with the necessary sensitivity and specificity to determine exposure to infection with T. saginata, and now merit an exhaustive evaluation prior to employment as routine diagnostic tools.  相似文献   

12.
Between February 18, 1995, and July 1, 1996, 38 cysts derived from New Zealand cattle were subjected to a diagnostic polymerase chain reaction (PCR) designed to identify genomic Taenia saginata DNA. No Tsaginata DNA was identified but an amplification product of 1078 bp was obtained consistently from several of the cysts. In Switzerland, suspect Tsaginata cysts are commonly positive for Tsaginata by PCR, but recently three cysts have also given a PCR fragment of 1078 bp, originating from a putatively unknown Taenia species.  相似文献   

13.
Taenia saginata cyst fluid was examined for host proteins; IgG1 and IgG2 as well as haemolytic complement activity were detected. Polyacrylamide gel electrophoresis revealed differences in proteinograms among the samples taken from 1-, 4-, and 10-month old cysts. Fluid from older cysts had fewer protein components and showed a weaker antigenic reaction with sera of bovines infected with T. saginata than that of younger cysts. The roles of antibody and complement in initiating degeneration of the parasite are discussed.  相似文献   

14.
A cross-sectional study to determine the prevalence of bovine cysticercosis and hydatidosis was conducted from October 2007 to March 2008 in cattle slaughtered at the Jimma municipal abattoir. Cyst distribution and viability of bovine cysticercosis and hydatidosis were also determined. A total of 512 carcasses were inspected of which 15 (2.93%) and 161 (31.44%) were infected with Taenia saginata metacestodes and hydatid cysts, respectively. From a total of 109 cysticerci collected from infected carcasses, 47 (43.12%) were viable. The anatomical distribution of the cysticerci was, shoulder muscle (39.5%), heart (33.9%), neck muscle (13.8%), tongue (10.1%), masseter muscles (1.8%) and diaphragm (0.9%). Of the 1171 hydatid cysts collected 223 (19.0%) were fertile, 505 (43.1%) sterile, 49 (29.8%) calcified and 94 (8.0%) contained pus. A greater proportion of fertile cysts were found in the lungs than in other organs. It was concluded that these zoonotic cestodes deserve due attention to safeguard public health, and that further studies are needed on genotyping, epidemiology and public health importance of Echinococcus granulosus in the study area.  相似文献   

15.
A sero-epidemiological survey of Taenia saginata cysticercosis was carried out to determine the prevalence of the infection in cattle presented for slaughter in Belgium. Between November 1997 and June 1998, a total of 1164 serum samples were collected in 20 export abattoirs. Meat inspection was routinely carried out by veterinary inspectors. Serum samples were examined for circulating parasite antigen using a monoclonal antibody-based sandwich enzyme-linked-immunosorbent assay (Ag-ELISA). Thirty six serum samples (3.09%) were found positive in the Ag-ELISA, while by meat inspection on the same animals cysticerci were detected in only three carcasses (0.26%). Sero-prevalence was positively correlated with the age of the animals. The sero-prevalence found in this study was more than 10 times higher than the annual prevalence (0.26%) reported by the Institute for Veterinary Inspection. This study clearly indicates that the classical meat inspection techniques detect only a minor fraction of the carcasses infected with cysticerci.  相似文献   

16.
A newly developed immunohistochemical test was used for the first time to demonstrate the presence of Taenia saginata (Cysticercus bovis) antigens in the lymph nodes of a heifer calf experimentally inoculated with Taenia saginata eggs. The new test should aid in the differential diagnosis of eosinophilic lymphadenitis in cattle.  相似文献   

17.
Giardia infections in domestic cattle has come under increasing scrutiny owing to the potential contamination of surface and ground waters through manure distribution on fields and pasture runoff. The objective of the study was to determine the prevalence and genotypes of Giardia duodenalis in beef calves in major beef cow calf farms in Alberta, Canada. Fecal samples were collected from beef calves aged 2-10 weeks at nine farms in Alberta. Samples were examined for the presence of G. duodenalis cysts by immunofluorescent staining. Giardia cysts were found in 168 of the 495 fecal samples examined, with prevalence ranging from 7 to 60% among farms. Genotypic analysis of positive isolates utilizing PCR and sequencing of a 292 bp fragment of the 16S-rRNA locus, revealed the hoofed livestock genotype in 41 of the 42 isolates. One isolate was identical to the Assemblage A genotype. The results of this study demonstrate that beef calves in this area are primarily infected with the livestock genotype which is thought to be specific to artiodactyl hosts and non-infective to humans. This suggests that the Giardia carried by beef cattle may be a minimal zoonotic threat.  相似文献   

18.
Based on ELISA results from randomly selected serum samples taken from 128 cattle from different administrative and urban districts in the federal state of Lower Saxony in Germany a seroprevalence estimate of Taenia saginata cysticercosis in this area was derived. This estimate was subsequently used to calculate the sample size required in an epidemiological study to determine the actual prevalence of this infection in the cattle population (n = 2 604 767) in this federal state. The sample size was calculated as 1518 and the samples were collected according to the distribution of cattle among the 48 administrative and urban districts in Lower Saxony. The samples were tested with an evaluated antibody ELISA. The results showed a positive antibody titre rate of 8.83% from the total tested samples.  相似文献   

19.
The larval stage (syn Cysticercus bovis) of the human tapeworm Taenia saginata causes cysticercosis in cattle, which has both aesthetic and food safety implications to consumers of beef. A monoclonal antibody-based immunohistochemical (IHC) assay developed to improve postmortem diagnosis of this parasite and a standard histological method were assessed to determine their fitness for intended use. Sections from 169 known-positive specimens of T. saginata from experimentally or naturally infected cattle, and from 30 known-negative specimens and lesions of various etiologies from non-infected cattle, were tested. The IHC assay identified significantly more known positive bovine cysticerci than the histological method (91.7% and 38.5%, respectively). Positive IHC staining occurred on sections from other cestode species, but should not affect the diagnostic specificity of this assay for bovine cysticercosis, due to the different host and/or tissue preferences amongst these parasites. Use of the IHC assay should improve the reliability of diagnosing lesions caused by degenerated cysticerci, facilitating more effective and efficient control of bovine cysticercosis.  相似文献   

20.
In March, 1973, a large feedlot near Phoenix, AZ, reported an increased incidence of bovine cysticercosis. Approximately 10% of cattle sent to slaughter from January to April, 1973, were infected with the cysticercus stage of Taenia saginata. One employee who worked at the feed mill and loaded hay in the fields was also found to be infected with T saginata. Recommendations for control of similar epizootics included educating employees about mode of transmission and improved personal hygiene, the inauguration of a surveillance program that included examination of employees prior to employment and periodically thereafter, maintenance of animal source and destination records, restriction of unauthorized personnel to critical areas, and periodic microbiologic assay of water supply.  相似文献   

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