RT Journal Article T1 Validation of a field based chromatin dispersion assay to assess sperm DNA fragmentation in the bottlenose dolphin (Tursiops truncatus) A1 Sánchez Calabuig, María Jesús A1 López-Fernández, Carmen A1 Martínez-Nevado, Eva A1 Pérez Gutiérrez, José Félix A1 de la Fuente, Julio A1 Johnston, Steve D A1 Blyde, David A1 Harrison, Keith A1 Gosálvez, Jaime AB Over the last two decades, there have been significant advances in the use of assisted reproductive technology for genetic and reproductive management of captive dolphin populations, including evaluation of sperm DNA quality. This study validated a customized sperm chromatin dispersion test (SCDt) for the bottlenose dolphin (Tursiops truncatus) as a means of assessing sperm DNA damage both in the field and in the laboratory. After performing the SCDt, two different sperm morphotypes were identified: (i) sperm with fragmented DNA showed large haloes of dispersed DNA fragments emerging from a compact sperm nucleoid core and (ii) sperm containing non-fragmented DNA displayed small compact haloes surrounded by a dense core of non-dispersed DNA and protein complex. Estimates of sperm DNA fragmentation by means of SCDt were directly comparable to results obtained following a two-tailed comet assay and showed a significant degree of correlation (r = 0.961; p < 0.001). This investigation also revealed that the SCDt, with minor modifications to the standard protocol, can be successfully conducted in the field using a LED florescence microscopy obtaining a high correlation (r = 0.993; p = 0.01) between the data obtained in the laboratory and in the field. PB Wiley SN 0936-6768 YR 2014 FD 2014 LK https://hdl.handle.net/20.500.14352/117852 UL https://hdl.handle.net/20.500.14352/117852 LA eng NO Sánchez-Calabuig, López-Fernández, Martínez-Nevado, Pérez-Gutiérrez, de la Fuente, Johnston, Blyde, Harrison, & Gosálvez. (2014). Validation of a field based chromatin dispersion assay to assess sperm DNA fragmentation in the bottlenose dolphin (Tursiops truncatus). Reproduction in Domestic Animals, 49(5), 761-768. https://doi.org/10.1111/RDA.12364 NO MJ Sanchez-Calabuig processed the samples, wrote the manuscript and contributed to data analysis. J Gosalvez and C Lopez-Fernandez conceived and designed the experiment, analysed the data, arranged the figures and corrected the manuscript. Stephen Johnston and David Blyde provided the semen samples and contributed with the semen analysis. Steve Johnston helped with the experiment design, contributed with the experiment performed in Sea Word Gold Coast and in the laboratory (Queensland University) and participated in the writing of manuscript. Finally, Keith Harrisson contributed with the semen cryopreservation at Sea World Gold Coast. DS Docta Complutense RD 9 abr 2025