Morphometric and chromatin assessment in brown bear (Ursus Arctos) ejaculated spermatozoa

Morphometric and chromatin assessment in brown bear (Ursus Arctos) ejaculated spermatozoa

V García-Macías, F Martínez-Pastor, P Paz, M Álvarez, S Borragan, F Martínez, E Anel and L Anel

Animal Reproduction, Cell Biology and Anatomy, University of León, Cabarceno Park, Cantabria, Spain

The Brown bear is a highly endangered species in Spain. The study of its spermatology will allow us to acquire the knowledge for establish a germplasm bank.  Sperm heads consist mainly of chromatin, thus their shape should be related to chromatin status. Potential problems in chromatin may result in subtle  changes in sperm head shape that could be detectable with computer-assisted morphology assessment (CASMA). Our objectives are to describe sperm  morphology results in brown bear ejaculates and to connect these parameters with those derived from sperm chromatin structure assay (SCSA). Four bears were electroejaculated under general anaesthesia. From each ejaculated we applied SCSA (Evenson, 2002; J Androl; 23:25–43) and morphometry  assessment (Diff-Quik and Sperm Class Analyser; Microptic S.L.). For SCSA we obtained the mean and standard deviation of the DNA fragmentation index  (SD-DFI). CASMA results included the area, perimeter, length, width and elipticity of heads. We analysed data using ANOVA (male as factor) and Spearman  correlations between morphometry and SCSA. The CASMA system detected subtle morphometric differences among spermatozoa from different bears (21.75 ± 2.14; 21.76 ±  2.32; 20.53 ± 2.40; 22.24 ± 1.69 area media ± IQ range for each bear). SD-DFI (6.9, 11.5, 5.5 and 12.1 for each bear) and the area rendered good correlations (r =  1; p < 0.01). Thus, SCSA and sperm head morphometry may be powerful tools to improve semen examination in the brown bear (Financed by CICYT