Fig 1.
Schematic representation of predicted restriction enzyme sites occurring in 12S ribosomal DNA amplified from taeniid cestodes in PCR-RFLP.
Numbers below each line represent the length of the 12S ribosomal DNA PCR product amplified from each species. Predicted restriction enzyme sites (DdeI, HinfI and HpaI) are shown above each gene product and the predicted position of enzyme sites for each species are shown in brackets.
Fig 2.
Examples of lesions detected in pigs from Uganda and Nepal that were either caused by Taenia solium or required further investigation to determine whether there was evidence that they were caused by T. solium or may have had had some other origin.
A, B and C: Examples of lesions in the liver, lung and kidney for which no evidence could be found to determine their likely cause, scale small divisions in mm; D: Viable T. solium cysticercus in muscle tissue, scale approx. 1cm; E: non-viable lesion in muscle bisected during cutting of the tissue and inferred as being a non-viable T. solium cyst, scale approx. 1cm; F: mature, viable Taenia hydatigena cysticercus embedded in the surface of the liver, scale approx. 1cm.
Fig 3.
Further examples of lesions detected in pigs from Uganda and Nepal that were either caused by Taenia solium or required further investigation to determine whether there was evidence that they were caused by T. solium or may have had had some other origin.
A: Immature, viable T. hydatigena cysticercus in the liver confirmed by DNA analyses, scale small divisions in mm; B: Non-viable lesion in the liver caused by T. hydatigena confirmed by DNA analyses, scale approx. 1cm; C, D: non-viable liver lesions in pigs from Nepal caused by Taenia asiatica confirmed by DNA analyses, scale large divisions in cm; E, F: Examples of smaller lesions cause by Echinococcus granulosus confirmed by DNA analyses in the liver and lungs of pigs from Nepal, scale large divisions in cm.
Fig 4.
Lesion in the lung of a pig caused by Metastrongylus spp.
A: macroscopic view of an uncut lesion, scale approx. 1cm; B: image taken through a dissection microscope of a cut lesion revealing the adult worm, scale approx. 1mm; C: histological section showing degenerate nematode cross-section with visible cuticle, musculature and uteri with embryos, scale 100μm; D: embryonated nematode egg, scale 50 μm.
Fig 5.
PCR-RFLP of DNA extracted from lesions recovered from pigs in Nepal.
3% agarose gels stained with SYBR green. Lanes 1–23, 12S PCR products digested with DdeI and HinfI, derived from pig lesions. Lanes 24–27, 12S PCR products digested with DdeI and HinfI from control DNA. (24) T. solium, (25) E. granulosus, (26) T. hydatigena, (27) T. saginata. (M) 100 bp DNA Ladder, Promega. For expected DNA fragment sizes refer to Fig 1.
Fig 6.
PCR-RFLP of DNA extracted from lesions confirming T. asiatica infection in Nepalese pigs.
(A) 12S PCR products separated on 1.2% agarose gel stained with SYBR green. (B) 12S PCR products digested with DdeI and HinfI and separated on 3% agarose gel stained with SYBR green. (1, 2) DNA from pig lesions, (3) T. asiatica, (4) T. saginata, (5) pig liver. (M) 100 bp DNA Ladder, Promega. For expected DNA fragment sizes refer to Fig 1.
Fig 7.
PCR-RFLP of DNA extracted from lesions recovered from pigs in Uganda.
3% agarose gel stained with SYBR green. Lanes 1–7, 12S PCR products digested with DdeI and HinfI. Lanes 8–14, 12S PCR products digested with HpaI. (1, 8), (2, 9) and (3, 10) are digested PCR products derived from the same lesion in the case of each pair. (4, 11) T. solium, (5, 12) T. hydatigena, (6, 13) E. granulosus, (7, 14) T. saginata control DNA. (M) 100 bp DNA Ladder, Promega. Lanes 1 and 8 are digested PCR products from a viable T. solium cysticercus from muscle tissue. For expected DNA fragment sizes refer to Fig 1.