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Cysticercus tenuicollis is the metacestode of canine tapeworm Taenia hydatigena, which has been reported in domestic and wild ruminants and is causing veterinary and economic losses in the meat industry. This study was conducted to determine the sequence variation in the mitochondrial cytochrome c oxidase subunit 1 (coxl) gene in 20 isolates of T. hydatigena metacestodes (cysticercus tenuicollis) collected from northern West Bank in Palestine. Nine haplotypes were detected, with one prevailing (55%). The total haplotype diversity (0.705) and the total nucleotide diversity (0.0045) displayed low genetic diversity among our isolates. Haplotype analysis showed a star-shaped network with a centrally positioned common haplotype. The Tajima's D, and Fu and Li's statistics in cysticercus tenuicollis population of this region showed a negative value, indicating deviations from neutrality and both suggested recent population expansion for the population. The findings of this study would greatly help to implement control and preventive measures for T. hydatigena larvae infection in Palestine.

Control measures to prevent human infections with the food-borne zoonotic helminth Taenia saginata are currently based on meat inspection, which shows rather low diagnostic sensitivity. To develop an immunoblot for detection of T. saginata-infected cattle, crude proteins of T. saginata cysts were extracted and separated with SDS-PAGE. The cyst antigens showed ten protein bands ranging from 260 to 14 kDa. T. saginata cyst proteins 260, 150, 130, 67, 60, 55, 50, and 23 kDa were immunoreactive with known positive sera of T. saginata-infected cattle but cross-reacted with sera from Echinocccus granulosus-infected ruminants. By contrast, 14- and 18-kDa cyst proteins reacted specifically with T. saginata-positive sera and thus might be potential candidates for the development of a T. saginata-specific immunoassay. Proteins of E. granulosus cysts and Taenia hydatigena cysts were also extracted and separated with SDS-PAGE. E. granulosus cysts revealed 11 protein bands ranging from 260 to 23 kDa. E. granulosus protein 60 kDa was immunoreactive with E. granulosus-positive sera only. The cyst of T. hydatigena showed 11 protein bands ranging from 290 to 14 kDa. The protein band 35 kDa showed cross-reaction with positive sera from both T. saginata- and E. granulosus-infected animals. A protein of 67 kDa was present in all three tested cestode species and was the major antigenic protein detected by sera of T. saginata- and E. granulosus-infected animals. Therefore, this protein represents a potential vaccine candidate against both cysticercosis and cystic echinococcosis in cattle.

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.

Two peptides, HP6-2 and Ts45S-10, were used as antigens for the detection of antibodies against Taenia saginata cysticercosis in serum and meat juice samples using enzyme-linked immunosorbent assay (ELISA). Positive control samples were obtained from animals experimentally infected (serum) and from animals naturally infected (meat juice). The two peptides and a pooled preparation of both peptides were evaluated, and their cut-off points with both sample categories were calculated. ELISA results from these different peptides were compared. Sensitivity and specificity of HP6-2 using serum were calculated as being 100 and 98%, respectively, showing to be higher than the values for the other antigens used. The average optical density (OD) value for negative samples was 0.646, whereas it was 1.702 for the positive control samples. This peptide was used to examine serum samples from animals with cysts and random field serum samples. For meat juice samples the pooled peptides showed the highest sensitivity and specificity, as they were 100 and 95%, respectively. The average OD values for the negative and the positive reference meat juice samples were 0.379 and 1.291, respectively. The optimal dilution of the meat juice samples for the ELISA was very low, as it was 1:20 using the pooled peptides, compared with 1:800 serum dilution using HP6-2. To the authors' knowledge, this is the first report of a successful testing for T. saginata cysticercosis using meat juice.

A total of 267 cysts were collected from March to December 2004 from two main abattoirs in northern Germany. The cysts were classified by the usual organoleptic methods during meat inspection as Cysticercus bovis. The reported prevalence of cysticercosis in the abattoirs was 0.48 and 1.08%, respectively. The cysts were examined macroscopically for description of their morphology and constituents and classified as viable or degenerating (dead). The DNA was extracted from these cysts and subjected to polymerase chain reaction (PCR) for evaluation of the detection methods used and to make certain that the cysts did indeed belong to C. bovis, as indicated at the slaughterhouses. Two sets of primers were used with different sensitivity levels. The first, HDP1, was able to detect 200 fg of Taenia saginata DNA and 100 pg of C. bovis DNA. The other primer set, HDP2, was able to detect 1 pg of T. saginata DNA and 1 ng of C. bovis DNA. No more than 52.4% of the samples tested positive for C. bovis in the PCR using both primers, while 20% of the viable cysts and 49.2% of the degenerating cysts tested negative with both primers.