Effect of the sexed semen process through flowcytometry and cryopreservation on the morphometry ofspermatozoid heads and chromatin stability
Bovine sexed semen has been commercially evaluateddue to its great economic value for sex selection in milk and beef cattle raising,with purity around 90% for the desired sex. However, its employment dependson the cryopreservation use. The objective of the present study was to analyzethe spermatic chromatin stability and morphometric alterations in spermatozoidheads from semen-donor bulls through computerized images obtained frommicroscopic slides of in natura sexed semen stained with toluidine blue,unfrozen sexed semen and from unfrozen conventional semen. Seventeenejaculated from 17 bulls were used in the confection the microscopic slides forthe morphometric analysis of the spermatic head and 15 ejaculated from 15bulls were used for the analysis of the spermatic chromatin stability. Onehundred digital images were obtained from each slide and were used tosegment 100 spermatozoid heads from each slide. Area (A), perimeter (P),width (W), length (L), width/length ratio (W/L), elipcity (E), shape factor (SF),lateral symmetry (LS) and anterior-posterior symmetry (APS) of all heads weredetermined through the use of softwares developed in the SCILAB. Fourierdescriptors with amplitude from 0 to 2 (F0, F1, F2) were also considered for thecharacterization and analysis of shape, and the spermatic chromatin wasevaluated in relation to compaction intensity and homogeneity. Based on resultsobtained, the dilution, staining and incubation process previous to theseparation process through flow cytometry and cryopreservation influenced themorphometry of spermatic cells; however, the chromatic compaction wasslightly affected by the sexed process through flow cytometry.
Advisor:Marcelo Emílio Beletti; Sony Dimas Bicudo; Elmo Gomes Diniz
School:Universidade Federal de Uberlândia
Source Type:Master's Thesis
Date of Publication:09/27/2007