Establishment of threshold infection levels of WSSV in different weight ranges of Penaeus vannamei using quantitative PCR (qPCR)
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Threshold infection level is the pathogen load of the test animals measured before the appearance of clinical signs and mortality. This study aims to establish the threshold infection levels of WSSV in different weight ranges of Penaeus vannamei using qPCR. Artificial infection experiments were conducted using four weight ranges (3–5 g, 7–8 g, 15–18 g, and 22–25 g). The LD50 of the different weight ranges of shrimps were achieved at viral dilution of 10-6 and 10-5 after 216–240 hpi, and the viral loads of these inoculums have a range of 105–106 WSSV DNA copies/g. The viral loads of the samples in the timecourse infection experiments when the mortalities started was determined at 109 WSSV DNA copies/g, while for the survivors was at 106 WSSV DNA copies/g. The threshold infection level of WSSV in shrimp was determined at 107 to 108 WSSV DNA copies/g. It was also found out that the threshold infection level was not weight dependent.
Suggested Citation
de la Pena, L. D., Arboleda, J. I., & Castellano, J. L. A. (2021). Establishment of threshold infection levels of WSSV in different weight ranges of Penaeus vannamei using quantitative PCR (qPCR). In F. A. Aya, L. D. de la Peña, N. D. Salayo, & E. A. Tendencia (Eds.), Proceedings of the International Workshop on the Promotion of Sustainable Aquaculture, Aquatic Animal Health, and Resource Enhancement in Southeast Asia (pp. 218–228). Tigbauan, Iloilo, Philippines: Aquaculture Department, Southeast Asian Fisheries Development Center.
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Conference paperISBN
9789719931102 (Print); 9789719931119 (PDF)
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