Submitted to: South Dakota Academy of Science Transaction
Publication Type: Abstract Only
Publication Acceptance Date: 6/30/2005
Publication Date: 8/1/2005
Citation: Harmon, A.F., Zarlenga, D.S., Hildreth, M.B. 2005. Multiplex pcr for the identification and differentiation of cattle nematodes in South Dakota [abstract]. South Dakota Academy of Science. Paper No. 28. Interpretive Summary:
Technical Abstract: Currently, no practical method for differentiating eggs obtained from fecal samples is available. A multiplex PCR assay was recently described which is capable of differentiating eggs at the genus level. This assay was designed to detect DNA extracted from fecal eggs and was validated using DNA from larva and eggs from experimentally-infected animals; however, the test has yet to be applied in the field on naturally-infected animals. To this end, we first infected two calves with Ostertagia ostertagi as a source of strongyle eggs. These eggs were used to develop an iodine solution based method for preserving strongyle eggs at room temperature and to assess more efficient methods for extracting DNA using commercially available kits that yield PCR products consistent with that reported previously for O. ostertagi. Subsequent to identifying the best method for DNA isolation, samples from 4 naturally infected South Dakota herds were evaluated from Watertown, and both Ostertagia and Cooperia were found in all 4 herds. Haemonchus was also found in one of the 4 herds tested; however, PCR products coincident with the presence of Trichostrongylus and Oesophagostomum were not detected. The PCR products generated from each sample did not appear to be proportional to the number of eggs present in the sample.